Publications by authors named "Zhenling Cui"

69 Publications

Deciphering microbial mechanisms underlying soil organic carbon storage in a wheat-maize rotation system.

Sci Total Environ 2021 Sep 15;788:147798. Epub 2021 May 15.

College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing 100193, China. Electronic address:

A link between microbial life history strategies and soil organic carbon storage in agroecosystems is presumed, but largely unexplored at the gene level. We aimed to elucidate whether and how differential organic material amendments (manure versus peat-vermiculite) affect, relative to sole chemical fertilizer application, the link between microbial life history strategies and soil organic carbon storage in a wheat-maize rotation field experiment. To achieve this goal, we combined bacterial 16S rRNA gene and fungal ITS amplicon sequencing, metagenomics and the assembly of genomes. Fertilizer treatments had a significantly greater effect on microbial community composition than aggregate size, with soil available phosphorus and potassium being the most important community-shaping factors. Limitation in labile carbon was linked to a K-selected oligotrophic life history strategy (Gemmatimonadetes, Acidobacteria) under sole chemical fertilizer application; defined by a significant enrichment of genes involved in resource acquisition, polymer hydrolysis, and competition. By contrast, excess of labile carbon promoted an r-selected copiotrophic life history strategy (Cytophagales, Bacillales, Mortierellomycota) under manure treatment; defined by a significant enrichment of genes involved in cellular growth. A distinct life history strategy was not observed under peat-vermiculite treatment, but rather a mix of both K-selected (Acidobacteria) and r-selected (Actinobacteria, Mortierellomycota) microorganisms. Compared to sole chemical fertilizer application, soil organic carbon storage efficiency was significantly increased by 26.5% and 50.0% under manure and peat-vermiculite treatments, respectively. Taken together, our results highlight the importance of organic material amendments, but in particular a one-time peat-vermiculite application, to promote soil organic carbon storage as a potential management strategy for sustainable agriculture.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147798DOI Listing
September 2021

Metagenomic insights into nitrogen and phosphorus cycling at the soil aggregate scale driven by organic material amendments.

Sci Total Environ 2021 Sep 24;785:147329. Epub 2021 Apr 24.

College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing 100193, China. Electronic address:

The soil microbiome, existing as interconnected communities closely associated with soil aggregates, is the key driver in nutrient cycling. However, the underlying genomic information encoding the machinery of the soil microbiome involved in nutrient cycling at the soil aggregate scale is barely known. Here comparative metagenomics and genome binning were applied to investigate microbial functional profiles at the soil aggregate scale under different organic material amendments in a long-term field experiment. Soil samples were sieved into large macroaggregates (>2 mm), macroaggregates (0.25-2 mm) and microaggregates (<0.25 mm). Microbial taxonomic and functional alpha diversity were significantly correlated to soil NO and SOC. The highest abundance of nasB, nirK, and amoA genes, which are responsible for denitrification and ammonia oxidizers driving nitrification, was observed in microaggregates. Both manure and peat treatments significantly decreased the abundance of napA and nrfA that encode enzymes involved in dissimilatory nitrate reduction to ammonium (DNRA). As a biomarker for soil inorganic P solubilization, the relative abundance of gcd was significantly increased in macroaggregates and large macroaggregates. Three nearly complete genomes of Nitrososphaeraceae (AOA) and seven bacterial genomes were shown to harbor a series of genes involved in nitrification and P solubilization, respectively. Our study provides comprehensive insights into the microbial genetic potential for DNRA and P-solubilizing activity across different soil aggregate fractions and fertilization regimes.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147329DOI Listing
September 2021

Mitigation of Multiple Environmental Footprints for China's Pig Production Using Different Land Use Strategies.

Environ Sci Technol 2021 04 1;55(8):4440-4451. Epub 2021 Apr 1.

College of Resources and Environmental Sciences; National Academy of Agriculture Green Development; Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing 100193, China.

Pig production contributes considerably to land use and greenhouse gas (GHG) and reactive nitrogen (Nr) emissions. Land use strategies were widely proposed, but the spillover effects on biological flow are rarely explored. Here, we simultaneously assessed the carbon (C), nitrogen (N), and cropland footprints of China's pig production at the provincial scale in 2017. The environmental impacts of land use strategies were further evaluated. Results show that one kg live-weight pig production generated an average of 1.9 kg CO-equiv and 59 g Nr emissions, occupying 3.5 m cropland, with large regional variations. A large reduction in GHG (58-64%) and Nr (12-14%) losses and occupied cropland (10-11%) could be achieved simultaneously if combined strategies of intensive crop production, improved feed-protein utilization efficiency, and feeding co-products were implemented. However, adopting a single strategy may have environmental side-effects. Reallocating cropland that pigs used for feed to plant food alternatives would enhance human-edible energy (3-20 times) and protein delivery (1-5 times) and reduce C and N footprints, except for rice and vegetables. Reallocating cropland to beef and milk production would decrease energy and protein supply. Therefore, a proper combination of land use strategies is essential to alleviate land use changes and nutrient emissions without sacrificing food supply.
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http://dx.doi.org/10.1021/acs.est.0c08359DOI Listing
April 2021

Cell-Free Approach for Non-canonical Amino Acids Incorporation Into Polypeptides.

Front Bioeng Biotechnol 2020 28;8:1031. Epub 2020 Sep 28.

Synthetic Biology Laboratory, School of Biology and Environmental Science, Queensland University of Technology, Brisbane, QLD, Australia.

Synthetic biology holds promise to revolutionize the life sciences and biomedicine via expansion of macromolecular diversity outside the natural chemical space. Use of non-canonical amino acids (ncAAs) via codon reassignment has found diverse applications in protein structure and interaction analysis, introduction of post-translational modifications, production of constrained peptides, antibody-drug conjugates, and novel enzymes. However, simultaneously encoding multiple ncAAs requires complex engineering and is sometimes restricted by the cell's poor uptake of ncAAs. In contrast the open nature of cell-free protein synthesis systems offers much greater freedom for manipulation and repurposing of the biosynthetic machinery by controlling the level and identity of translational components and reagents, and allows simultaneous incorporation of multiple ncAAs with non-canonical side chains and even backbones (N-methyl, D-, β-amino acids, α-hydroxy acids etc.). This review focuses on the two most used -based cell-free protein synthesis systems; cell extract- and PURE-based systems. The former is a biological mixture with >500 proteins, while the latter consists of 38 individually purified biomolecules. We delineate compositions of these two systems and discuss their respective advantages and applications. Also, we dissect the translational components required for ncAA incorporation and compile lists of ncAAs that can be incorporated into polypeptides via different acylation approaches. We highlight the recent progress in using unnatural nucleobase pairs to increase the repertoire of orthogonal codons, as well as using tRNA-specific ribozymes for acylation. We summarize advances in engineering of translational machinery such as tRNAs, aminoacyl-tRNA synthetases, elongation factors, and ribosomes to achieve efficient incorporation of structurally challenging ncAAs. We note that, many engineered components of biosynthetic machinery are developed for the use but are equally applicable to the systems. These are included in the review to provide a comprehensive overview for ncAA incorporation and offer new insights for the future development in cell-free systems. Finally, we highlight the exciting progress in the genomic engineering, resulting in strains free of amber and some redundant sense codons. These strains can be used for preparation of cell extracts offering multiple reassignment options.
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http://dx.doi.org/10.3389/fbioe.2020.01031DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7550873PMC
September 2020

Discovery and mechanism of a pH-dependent dual-binding-site switch in the interaction of a pair of protein modules.

Sci Adv 2020 Oct 23;6(43). Epub 2020 Oct 23.

CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, China.

Many important proteins undergo pH-dependent conformational changes resulting in "on-off" switches for protein function, which are essential for regulation of life processes and have wide application potential. Here, we report a pair of cellulosomal assembly modules, comprising a cohesin and a dockerin from , which interact together following a unique pH-dependent switch between two functional sites rather than on-off states. The two cohesin-binding sites on the dockerin are switched from one to the other at pH 4.8 and 7.5 with a 180° rotation of the bound dockerin. Combined analysis by nuclear magnetic resonance spectroscopy, crystal structure determination, mutagenesis, and isothermal titration calorimetry elucidates the chemical and structural mechanism of the pH-dependent switching of the binding sites. The pH-dependent dual-binding-site switch not only represents an elegant example of biological regulation but also provides a new approach for developing pH-dependent protein devices and biomaterials beyond an on-off switch for biotechnological applications.
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http://dx.doi.org/10.1126/sciadv.abd7182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7608827PMC
October 2020

Safeguarding Food Supply and Groundwater Safety for Maize Production in China.

Environ Sci Technol 2020 08 6;54(16):9939-9948. Epub 2020 Aug 6.

College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.

Quantifying sustainable nitrogen (N) management at the national scale is critical for developing targeted policies and strategies to simultaneously achieve food security and groundwater protection. In this study, we report county-scale optimization scenarios for Chinese maize production and evaluate their outcomes for safeguarding food supply and groundwater safety. First, we performed random forest regression modeling to simulate NO leaching based on a meta-analysis that integrates climate, soil, water, and N balance parameters. The NO leaching was then mapped for 1406 counties based on data compiled from 2.89 million farmer surveys. Average NO leaching during the maize growth season was estimated to be 27.6 kg N ha, and 56% of counties had groundwater whose nitrate concentrations exceeded drinking water safety levels during 2005-2014. The top 5% farmers in each county produced not only more grain but also greater NO leaching. Scenario analysis of potential management changes found that when these top producers combined optimal N management practices, national N use in Chinese maize system was reduced by 25%, from 9.1 to 6.9 Mt, while maize production increased by 6.1%. Modeled NO leaching was 0.58 Mt, which was 31% lower than groundwater safety levels and 53% lower than the current leaching amount. This study provides evidence that integrated crop and N management practices implemented at the county level safeguard both maize crop food security and enhance environment sustainability.
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http://dx.doi.org/10.1021/acs.est.9b05642DOI Listing
August 2020

Estimating regional N application rates for rice in China based on target yield, indigenous N supply, and N loss.

Environ Pollut 2020 Aug 28;263(Pt B):114408. Epub 2020 Mar 28.

Ministry of Agriculture and Rural Affairs Key Laboratory of Plant Nutrition and Fertilizer, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100081, PR China. Electronic address:

Decision-making related to nitrogen (N) applications based solely on historic experience is still widespread in China, the country with the largest rice production and N fertilizer use. By connecting N application rates with target N uptake, indigenous N supply, and N loss estimates collected from 1078 on-farm experiments, we determined regional N application rates for five rice-based agroecosystems, including a quantification of the reduction potential of application rates when using low-loss N sources, such as organic N and slow-release N. Based on our results, the moderate regional N application rates were 165, 180, 160, 153, and 173 kg N ha for single, middle-CE (Central and Eastern China), middle-SW (Southwestern China), early, and late rice, respectively; lower (99-148 kg N ha) and upper (195-217 kg N ha) limits of N application rates were developed for situations with sufficient and insufficient indigenous N supplies, respectively. The depletion of soil N mineralization was quantified as 46.8-67.3 kg ha, and straw return is determined to be a robust measure to maintain soil N balance. Substituting manure or slow-release N for conventional N fertilizer significantly decreased N losses via NH volatilization, leaching, runoff, and NO emissions. Overall, we observed 7.2-11.3 percent point reductions of N loss rate for low-loss N sources when compared to conventional N applications. On average, total N application rates could be theoretically reduced by 27 kg N ha by using a slow-release N fertilizer, or by 30 kg N ha when using manure due to their effectiveness at decreasing system N losses. Greater productivity, sustainable soil fertility, and a lower risk of N pollution would result from the ideal N application rate coupled with appropriate management practices. Widespread adoption of using low-loss N sources could become a key solution for future reduction in environmental N pollution and agricultural N inputs.
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http://dx.doi.org/10.1016/j.envpol.2020.114408DOI Listing
August 2020

Phosphorus flow analysis in the maize based food-feed-energy systems in China.

Environ Res 2020 05 2;184:109319. Epub 2020 Mar 2.

College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, PR China.

Phosphorus (P) is an essential and limiting nutrient for agricultural systems, where the demand for agricultural products such as food, feed, and bio-fuel are the major drivers of the intensification of agricultural production systems. Globally, maize is one of three main cereal crops, a main feedstock for animal production and a substrate for the production of bio-ethanol. This study investigated P flows through the multiple utilization systems of maize (as represented by the subsystems of food, feed and energy production) at a crop level of 2016 as reference year and made future predictions of P flows for the year 2030 based on different scenarios for food-feed-energy systems in China. For 2016, the subsystem of animal production resulted in the highest waste of P due to inappropriate manure management, but the subsystem of value-added products (Bio-fuel production, distillers dried grains with solubles (DDGS), maize-oil) showed the lowest P use efficiency (39%). From the value-added subsystem, 17% of P from the process flow to the subsystem of animal production as DDGS, and 61% of P is wasted associated with wastewater and sludge. Future scenarios of structural adjustments in the maize consumption system predict that the supply of maize for animal feed will be threatened if the policy of the Biofuel National Promotion before 2020 is fully implemented in China, as current maize production will not meet the future demand of food, feed and energy simultaneously. The results emphasized the use of P waste resources and better sludge management from a systems perspective. This also implied the importance of exploring coordinated development and integrated strategies for sustainable P flow management in multiple utilization systems.
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http://dx.doi.org/10.1016/j.envres.2020.109319DOI Listing
May 2020

Calculating socially optimal nitrogen (N) fertilization rates for sustainable N management in China.

Sci Total Environ 2019 Oct 24;688:1162-1171. Epub 2019 Jun 24.

Center for Resources, Environment and Food Security, China Agricultural University, Beijing 100193, China. Electronic address:

Current nitrogen (N) fertilization rates in China have incurred high social costs in the drive to achieve higher yields and economic returns. We conducted an intensive nation-wide investigation to estimate the socially optimal N rate (SOR) for Chinese maize, rice and wheat as a balance between crop productivity, farm income, ecological health and human health. The social cost of N impacts (SCN) was calculated based on 2210 field observations reported in 264 publications. The estimated SCN for three cereal crops grown in China was in the range $142-218 ha at medium N fertilization rates (173-204 kg N ha). The net benefits of N use were calculated as the differences between private profitability and the SCN. The minimum N application rate with maximized net benefit was estimated as the SOR calculated from data compiled from 27,476 on-farm year-site trials. The average SOR was in the range 149-160 kg ha; values in this range were 18.1-23.7% lower than the privately optimal N rate (POR). The yield losses associated with implementation of the SOR were not significant (p < 0.01) compared with the yield of POR implementation. The POR calculates the minimum N application required to maximize private profitability, i.e., traditional N recommended practice. Compared with the POR, implementation of SOR reduced reactive N losses by 17.8-39.0%, and the SCN by 18.8-30.9%. Finally, we simulated the SOR at the county level for each soil type based on data collected from no-N control plots yields and maximum achieved yields (p < 0.01). Thus, we estimated the SOR at the Chinese county level for three cereal crops using direct on-farm measurements. This study provide updated estimates of optimizing N management to simultaneously address production and pollution problems in China and other similar regions of the world.
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http://dx.doi.org/10.1016/j.scitotenv.2019.06.398DOI Listing
October 2019

Newer and select maize, wheat, and rice varieties can help mitigate N footprint while producing more grain.

Glob Chang Biol 2019 Dec 11;25(12):4273-4281. Epub 2019 Sep 11.

Center for Animal Health and Productivity, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA, USA.

Sustainably feeding the growing population amid a changing climate and dwindling resources is a grand challenge facing mankind. Decades-long advancement in crop breeding has progressively elevated yield potential, markedly enhancing global food production capacity. However, relevant impact on reactive N (Nr) emissions associated with crop variety improvement has not been explicitly described. Here, we report multitiered evidence that newer and select maize, wheat, and rice varieties developed in China have the capacity to substantially lower Nr losses while producing more grain. First, we pooled studies featuring side-by-side comparison of different varieties, totaling 269 paired observations, to demonstrate that collectively, relatively newer varieties of maize, wheat, and rice had less Nr emissions (9.6%-23.5%) while yielding more grains (7.3%-11.2%) compared to older varieties under wide-ranging conditions. Next, we built an extended database (142 field studies with 833 observations) and comprehensively evaluated the Nr-loss reduction potential of newer varieties (2000 and after) versus older ones (1985-1999). We found that newer varieties had Nr emission factors (N loss as a percentage of N applied after correcting for background emissions) 18.2%-75.7% less for N O, 18.3%-75.7% less for , and -8.5% to 22.8% less for NH , while producing more grains (16.0%-24.4%). Individual varieties differed markedly in yield-emission scores. A nationwide farmer survey (2.47 million responses) indicated tremendous opportunities for a new way of management intervention. Coupling variety selection with sound N and other agronomic management can help lower N footprint while producing more grain.
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http://dx.doi.org/10.1111/gcb.14798DOI Listing
December 2019

Oxidization of TGFβ-activated kinase by MPT53 is required for immunity to Mycobacterium tuberculosis.

Nat Microbiol 2019 08 20;4(8):1378-1388. Epub 2019 May 20.

Shanghai Key Lab of Tuberculosis, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China.

Mycobacterium tuberculosis (Mtb)-derived components are usually recognized by pattern recognition receptors to initiate a cascade of innate immune responses. One striking characteristic of Mtb is their utilization of different type VII secretion systems to secrete numerous proteins across their hydrophobic and highly impermeable cell walls, but whether and how these Mtb-secreted proteins are sensed by host immune system remains largely unknown. Here, we report that MPT53 (Rv2878c), a secreted disulfide-bond-forming-like protein of Mtb, directly interacts with TGF-β-activated kinase 1 (TAK1) and activates TAK1 in a TLR2- or MyD88-independent manner. MPT53 induces disulfide bond formation at C on TAK1 to facilitate its interaction with TRAFs and TAB1, thus activating TAK1 to induce the expression of pro-inflammatory cytokines. Furthermore, MPT53 and its disulfide oxidoreductase activity is required for Mtb to induce the host inflammatory responses via TAK1. Our findings provide an alternative pathway for host signalling proteins to sense Mtb infection and may favour the improvement of current vaccination strategies.
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http://dx.doi.org/10.1038/s41564-019-0436-3DOI Listing
August 2019

Generalizable Protein Biosensors Based on Synthetic Switch Modules.

J Am Chem Soc 2019 05 10;141(20):8128-8135. Epub 2019 May 10.

CSIRO-QUT Synthetic Biology alliance, Centre for Tropical Crops and Biocommodities, School of Earth, Environmental and Biological Sciences , Queensland University of Technology , Brisbane , QLD 4001 , Australia.

Allosteric protein switches are key controllers of information and energy processing in living organisms and are desirable engineered control tools in synthetic systems. Here we present a generally applicable strategy for construction of allosteric signaling systems with inputs and outputs of choice. We demonstrate conversion of constitutively active enzymes into peptide-operated synthetic allosteric ON switches by insertion of a calmodulin domain into rationally selected sites. Switches based on EGFP, glucose dehydrogenase, NanoLuciferase, and dehydrofolate reductase required minimal optimization and demonstrated a dynamic response ranging from 1.8-fold in the former case to over 200-fold in the latter case. The peptidic nature of the calmodulin ligand enables incorporation of such synthetic switch modules into higher order sensory architectures. Here, a ligand-mediated increase in proximity of the allosteric switch and the engineered activator peptide modulates biosensor's activity. Created biosensors were used to measure concentrations of clinically relevant drugs and biomarkers in plasma, saliva, and urine with accuracy comparable to that of the currently used clinical diagnostic assays. The approach presented is generalizable as it allows rapid construction of efficient protein switches that convert binding of a broad range of analytes into a biochemical activity of choice enabling construction of artificial signaling and metabolic circuits of potentially unlimited complexity.
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http://dx.doi.org/10.1021/jacs.8b12298DOI Listing
May 2019

Estimating soil nitrate leaching of nitrogen fertilizer from global meta-analysis.

Sci Total Environ 2019 Mar 4;657:96-102. Epub 2018 Dec 4.

Key Lab of Plant-Soil Interaction, Ministry of Education, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China. Electronic address:

Global estimates of soil nitrate leaching of applied nitrogen (N) in agricultural production systems are not imprecise; however, the results of some field experiments have suggested that nitrate leaching responds exponentially rather than linearly to increasing N inputs. In this study, we compiled field data on nitrate leaching for 324 site-year combinations extracted from 86 peer-reviewed articles to test the hypothesis that in response to N fertilizer addition, soil nitrate leaching emission factors (EF) do not remain constant, but rather increase rapidly with increasing rates of N application. The averaged overall results showed that the proportional change in the EF response to increasing N input (ΔEF, %) was 0.042. Because this value was positive and significantly different from zero, our results demonstrate that EF is not constant, but rather increases with N addition. We compared our ΔEF response pattern with other constant EF patterns, and found that the 30% EF estimate of the Intergovernmental Panel on Climate Change and the 19% EF used in another published model were too high. A global estimate of soil nitrate leaching in arable uplands calculated with our ΔEF pattern was substantially lower than other estimates calculated with other procedures. In conclusion, our ΔEF pattern provided a globally applicable procedure for more accurate estimation of leaching loss and potential environmental costs incurred by various N application gradients.
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http://dx.doi.org/10.1016/j.scitotenv.2018.12.029DOI Listing
March 2019

Nuclear E-Cadherin Acetylation Promotes Colorectal Tumorigenesis via Enhancing β-Catenin Activity.

Mol Cancer Res 2019 02 6;17(2):655-665. Epub 2018 Nov 6.

Key Laboratory of Stem Cell Biology, Shanghai Jiao Tong University School of Medicine (SJTUSM) and Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS), Shanghai, P.R. China.

The E-cadherin/β-catenin signaling pathway plays a critical role in the maintenance of epithelial architecture and regulation of tumor progression. Normally, E-cadherin locates on the cell surface with its cytosolic domain linking to the actin cytoskeleton through interaction with catenins. Although the nuclear localization of E-cadherin has been frequently observed in various types of cancers, little is known regarding the functional consequences of its nuclear translocation. Here, we showed that in colorectal cancer samples and cell lines, E-cadherin localized in the nucleus; and the nuclear localization was mediated through protein interaction with CTNND1. In the nucleus, E-cadherin was acetylated by CREB-binding protein at Lysine and Lysine in its β-catenin-binding domain, and the acetylation can be reversed by SIRT2. Acetylation of nuclear E-cadherin attenuated its interaction with β-catenin, which therefore released β-catenin from the complex, resulting in increased expression of its downstream genes and accelerated tumor growth and migration. Further study showed that acetylation level of nuclear E-cadherin had high prognostic significance in clinical colorectal samples. Taken together, our findings reveal a novel mechanism of tumor progression through posttranslational modification of E-cadherin, which may serve as a potential drug target of tumor therapy. IMPLICATIONS: This finding that acetylation of nuclear E-cadherin regulates β-catenin activity expands our understanding of the acetylation of E-cadherin promotes colorectal cancer cell growth and suggests novel therapeutic approaches of targeting acetylation in tumors.
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http://dx.doi.org/10.1158/1541-7786.MCR-18-0637DOI Listing
February 2019

MicroRNA-27a controls the intracellular survival of Mycobacterium tuberculosis by regulating calcium-associated autophagy.

Nat Commun 2018 10 16;9(1):4295. Epub 2018 Oct 16.

Shanghai Key Lab of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China.

Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) kills millions every year, and there is urgent need to develop novel anti-TB agents due to the fast-growing of drug-resistant TB. Although autophagy regulates the intracellular survival of Mtb, the role of calcium (Ca) signaling in modulating autophagy during Mtb infection remains largely unknown. Here, we show that microRNA miR-27a is abundantly expressed in active TB patients, Mtb-infected mice and macrophages. The target of miR-27a is the ER-located Ca transporter CACNA2D3. Targeting of this transporter leads to the downregulation of Ca signaling, thus inhibiting autophagosome formation and promoting the intracellular survival of Mtb. Mice lacking of miR-27a and mice treated with an antagomir to miR-27a are more resistant to Mtb infection. Our findings reveal a strategy for Mtb to increase intracellular survival by manipulating the Ca-associated autophagy, and may also support the development of host-directed anti-TB therapeutic approaches.
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http://dx.doi.org/10.1038/s41467-018-06836-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6191460PMC
October 2018

Closing water productivity gaps to achieve food and water security for a global maize supply.

Sci Rep 2018 10 3;8(1):14762. Epub 2018 Oct 3.

College of Resources & Environmental Sciences, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, Beijing, 100193, China.

To achieve food and water security, it is as important to close the water productivity (WP) gap (which was defined as the difference between the maximum attainable WP and the currently achieved WP at the field scale) as it is to close yield gaps. However, few studies have provided quantitative estimates of existing WP gaps and constraining factors for global maize production. Using a meta-analysis of 473 published studies covering 31 countries and 5,553 observations (932 site-years), we found the global average WP value for irrigated maize was 18.6 kg ha mm. These WPs varied by factors such as seasonal precipitation, irrigation regimes, soil organic matter and soil pH. In current production systems, there exists a huge scope for improvement in maize WP, but the reported field experiments achieved only 20-46% of potential WP across all countries. Considering the future, raising WP to 85% of potential WP by 2050, a 100% increase in maize production could be achieved with 20% less planted area and 21% less water consumption than in 2005. Closing the WP gap may be critical to ensuring food security and achieving sustainable global agriculture.
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http://dx.doi.org/10.1038/s41598-018-32964-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6170377PMC
October 2018

Transcription factors Rv0081 and Rv3334 connect the early and the enduring hypoxic response of Mycobacterium tuberculosis.

Virulence 2018 ;9(1):1468-1482

a State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science , Fudan University , Shanghai , China.

The ability of Mycobacterium tuberculosis (M. tb) to survive and persist in the host for decades in an asymptomatic state is an important aspect of tuberculosis pathogenesis. Although adaptation to hypoxia is thought to play a prominent role underlying M. tb persistence, how the bacteria achieve this goal is largely unknown. Rv0081, a member of the DosR regulon, is induced at the early stage of hypoxia while Rv3334 is one of the enduring hypoxic response genes. In this study, we uncovered genetic interactions between these two transcription factors. RNA-seq analysis of ΔRv0081 and ΔRv3334 revealed that the gene expression profiles of these two mutants were highly similar. We also found that under hypoxia, Rv0081 positively regulated the expression of Rv3334 while Rv3334 repressed transcription of Rv0081. In addition, we demonstrated that Rv0081 formed dimer and bound to the promoter region of Rv3334. Taken together, these data suggest that Rv0081 and Rv3334 work in the same regulatory pathway and that Rv3334 functions immediately downstream of Rv0081. We also found that Rv3334 is a bona fide regulator of the enduring hypoxic response genes. Our study has uncovered a regulatory pathway that connects the early and the enduring hypoxic response, revealing a transcriptional cascade that coordinates the temporal response of M. tb to hypoxia.
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http://dx.doi.org/10.1080/21505594.2018.1514237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6177252PMC
April 2019

Oligonucleotide-mediated tRNA sequestration enables one-pot sense codon reassignment in vitro.

Nucleic Acids Res 2018 07;46(12):6387-6400

Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia.

Sense codon reassignment to unnatural amino acids (uAAs) represents a powerful approach for introducing novel properties into polypeptides. The main obstacle to this approach is competition between the native isoacceptor tRNA(s) and orthogonal tRNA(s) for the reassigned codon. While several chromatographic and enzymatic procedures for selective deactivation of tRNA isoacceptors in cell-free translation systems exist, they are complex and not scalable. We designed a set of tRNA antisense oligonucleotides composed of either deoxy-, ribo- or 2'-O-methyl ribonucleotides and tested their ability to efficiently complex tRNAs of choice. Methylated oligonucleotides targeting sequence between the anticodon and variable loop of tRNASerGCU displayed subnanomolar binding affinity with slow dissociation kinetics. Such oligonucleotides efficiently and selectively sequestered native tRNASerGCU directly in translation-competent Escherichia coli S30 lysate, thereby, abrogating its translational activity and liberating the AGU/AGC codons. Expression of eGFP protein from the template harboring a single reassignable AGU codon in tRNASerGCU-depleted E. coli lysate allowed its homogeneous modification with n-propargyl-l-lysine or p-azido-l-phenylalanine. The strategy developed here is generic, as demonstrated by sequestration of tRNAArgCCU isoacceptor in E. coli translation system. Furthermore, this method is likely to be species-independent and was successfully applied to the eukaryotic Leishmania tarentolae in vitro translation system. This approach represents a new direction in genetic code reassignment with numerous practical applications.
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http://dx.doi.org/10.1093/nar/gky365DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6158751PMC
July 2018

Lysine acetylation of DosR regulates the hypoxia response of Mycobacterium tuberculosis.

Emerg Microbes Infect 2018 Mar 21;7(1):34. Epub 2018 Mar 21.

Shanghai Key Laboratory of Tuberculosis, Clinic and Research Center of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, PR China.

Tuberculosis caused by Mycobacterium tuberculosis (Mtb) infection remains a large global public health problem. One striking characteristic of Mtb is its ability to adapt to hypoxia and trigger the ensuing transition to a dormant state for persistent infection, but how the hypoxia response of Mtb is regulated remains largely unknown. Here we performed a quantitative acetylome analysis to compare the acetylation profile of Mtb under aeration and hypoxia, and showed that 377 acetylation sites in 269 Mtb proteins were significantly changed under hypoxia. In particular, deacetylation of dormancy survival regulator (DosR) at K182 promoted the hypoxia response in Mtb and enhanced the transcription of DosR-targeted genes. Mechanistically, recombinant DosR protein demonstrated enhanced DNA-binding activity in comparison with DosR protein. Moreover, Rv0998 was identified as an acetyltransferase that mediates the acetylation of DosR at K182. Deletion of Rv0998 also promoted the adaptation of Mtb to hypoxia and the transcription of DosR-targeted genes. Mice infected with an Mtb strain containing acetylation-defective DosR had much lower bacterial counts and less severe histopathological impairments compared with those infected with the wild-type strain. Our findings suggest that hypoxia induces the deacetylation of DosR, which in turn increases its DNA-binding ability to promote the transcription of target genes, allowing Mtb to shift to dormancy under hypoxia.
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http://dx.doi.org/10.1038/s41426-018-0032-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5861037PMC
March 2018

Pursuing sustainable productivity with millions of smallholder farmers.

Nature 2018 03 7;555(7696):363-366. Epub 2018 Mar 7.

Institute of Agricultural Resources and Environment, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050051, China.

Sustainably feeding a growing population is a grand challenge, and one that is particularly difficult in regions that are dominated by smallholder farming. Despite local successes, mobilizing vast smallholder communities with science- and evidence-based management practices to simultaneously address production and pollution problems has been infeasible. Here we report the outcome of concerted efforts in engaging millions of Chinese smallholder farmers to adopt enhanced management practices for greater yield and environmental performance. First, we conducted field trials across China's major agroecological zones to develop locally applicable recommendations using a comprehensive decision-support program. Engaging farmers to adopt those recommendations involved the collaboration of a core network of 1,152 researchers with numerous extension agents and agribusiness personnel. From 2005 to 2015, about 20.9 million farmers in 452 counties adopted enhanced management practices in fields with a total of 37.7 million cumulative hectares over the years. Average yields (maize, rice and wheat) increased by 10.8-11.5%, generating a net grain output of 33 million tonnes (Mt). At the same time, application of nitrogen decreased by 14.7-18.1%, saving 1.2 Mt of nitrogen fertilizers. The increased grain output and decreased nitrogen fertilizer use were equivalent to US$12.2 billion. Estimated reactive nitrogen losses averaged 4.5-4.7 kg nitrogen per Megagram (Mg) with the intervention compared to 6.0-6.4 kg nitrogen per Mg without. Greenhouse gas emissions were 328 kg, 812 kg and 434 kg CO equivalent per Mg of maize, rice and wheat produced, respectively, compared to 422 kg, 941 kg and 549 kg CO equivalent per Mg without the intervention. On the basis of a large-scale survey (8.6 million farmer participants) and scenario analyses, we further demonstrate the potential impacts of implementing the enhanced management practices on China's food security and sustainability outlook.
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http://dx.doi.org/10.1038/nature25785DOI Listing
March 2018

Lipoprotein MPT83 Induces Apoptosis of Infected Macrophages by Activating the TLR2/p38/COX-2 Signaling Pathway.

J Immunol 2017 06 15;198(12):4772-4780. Epub 2017 May 15.

Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China;

Tuberculosis caused by continues to pose a serious global health threat. The attenuated bacillus Calmette-Guérin, as the only licensed vaccine, has limited protective efficacy against TB. The development of more effective antituberculosis vaccines is urgent and demands for further identification and understanding of Ags. MPT83 (), a secreted mycobacterial lipoprotein, has been applied into subunit vaccine development and shown protective effects against infection in animals; however, the understanding of the underlying mechanism is limited. In present study, we systematically studied the effect of MPT83 on macrophage apoptosis by constructing strain overexpressing MPT83 (MS_MPT83) and purifying rMPT83 protein. We found that MPT83 induced apoptosis in both human and mouse macrophages. MPT83 induced cyclooxygenase-2 (COX-2) expression at both the transcriptional and protein levels in macrophages, whereas silencing or inhibiting COX-2 blocked rMPT83-induced apoptosis or the enhanced apoptotic response to MS_MPT83 in comparison with transfected with pMV261 vector (MS_Vec), indicating that COX-2 is required for MPT83-induced apoptosis. Additionally, deficiency led to significant reduction of COX-2 expression, accompanied by less apoptosis in macrophages stimulated with rMPT83 or infected with MS_MPT83. Moreover, the activation of p38 accounted for MPT83-induced COX-2 expression. Finally, lower bacteria burdens in the lungs and spleens and enhanced survival were observed in mice i.v. infected with MS_MPT83 compared with MS_Vec. Taken together, our results established a proapoptotic effect of MPT83 and identified the TLR2/p38/COX-2 axis in MPT83-induced macrophage apoptosis.
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http://dx.doi.org/10.4049/jimmunol.1700030DOI Listing
June 2017

A high plant density reduces the ability of maize to use soil nitrogen.

PLoS One 2017 24;12(2):e0172717. Epub 2017 Feb 24.

Key Laboratory of Plant-Soil Interactions, Ministry of Education, Center for Resources, Environment and Food Security, China Agricultural University, Beijing, China.

Understanding the physiological changes associated with high grain yield and high N use efficiency (NUE) is important when increasing the plant density and N rate to develop optimal agronomic management. We tested the hypothesis that high plant densities resulting in crowding stress reduce the ability of plants to use the N supply post-silking, thus decreasing the grain yield and NUE. In 2013 and 2014, a field experiment, with five N-application rates and three plant densities (6.0, 7.5, and 9.0 plants m-2), was conducted in the North China Plain (NCP). The calculated maximum grain yield and agronomic use efficiency (AEN) at a density of 7.5 plants m-2 were 12.4 Mg ha-1 and 39.3 kg kg-1, respectively, which were significantly higher than the values obtained at densities of 6.0 (11.3 Mg ha-1 and 30.2 kg kg-1) and 9.0 plant m-2 (11.7 Mg ha-1 and 27.8 kg kg-1). A high plant density of 9.0 plants m-2 decreased the post-silking N accumulation, leaf N concentration and net photosynthesis, which reduced the post-silking dry matter production, resulting in a low yield and NUE. Although a relatively low grain yield was observed at a density of 9.0 plants m-2, the optimal N rate increased from 150 to 186 kg N ha-1 at a density of 7.5 plants m-2. These results indicate that high plant densities with crowding stress reduce the ability of plants to use soil N during the post-silking period, and high rate of N fertilizer was needed to increase grain yield. We conclude that selecting the appropriate plant density combined with optimal N management could increase grain yields and the NUE in the NCP.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0172717PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5325311PMC
August 2017

Designing a new cropping system for high productivity and sustainable water usage under climate change.

Sci Rep 2017 02 3;7:41587. Epub 2017 Feb 3.

Center for Resources, Environment and Food Security, China Agricultural University, Beijing 100193, China.

The food supply is being increasingly challenged by climate change and water scarcity. However, incremental changes in traditional cropping systems have achieved only limited success in meeting these multiple challenges. In this study, we applied a systematic approach, using model simulation and data from two groups of field studies conducted in the North China Plain, to develop a new cropping system that improves yield and uses water in a sustainable manner. Due to significant warming, we identified a double-maize (M-M; Zea mays L.) cropping system that replaced the traditional winter wheat (Triticum aestivum L.) -summer maize system. The M-M system improved yield by 14-31% compared with the conventionally managed wheat-maize system, and achieved similar yield compared with the incrementally adapted wheat-maize system with the optimized cultivars, planting dates, planting density and water management. More importantly, water usage was lower in the M-M system than in the wheat-maize system, and the rate of water usage was sustainable (net groundwater usage was ≤150 mm yr). Our study indicated that systematic assessment of adaptation and cropping system scale have great potential to address the multiple food supply challenges under changing climatic conditions.
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http://dx.doi.org/10.1038/srep41587DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5290742PMC
February 2017

Combining Sense and Nonsense Codon Reassignment for Site-Selective Protein Modification with Unnatural Amino Acids.

ACS Synth Biol 2017 03 30;6(3):535-544. Epub 2016 Dec 30.

Institute for Molecular Bioscience, The University of Queensland , St Lucia, QLD 4072, Australia.

Incorporation of unnatural amino acids (uAAs) via codon reassignment is a powerful approach for introducing novel chemical and biological properties to synthesized polypeptides. However, the site-selective incorporation of multiple uAAs into polypeptides is hampered by the limited number of reassignable nonsense codons. This challenge is addressed in the current work by developing Escherichia coli in vitro translation system depleted of specific endogenous tRNAs. The translational activity in this system is dependent on the addition of synthetic tRNAs for the chosen sense codon. This allows site-selective uAA incorporation via addition of tRNAs pre- or cotranslationally charged with uAA. We demonstrate the utility of this system by incorporating the BODIPY fluorophore into the unique AGG codon of the calmodulin(CaM) open reading frame using in vitro precharged BODIPY-tRNA. The deacylated tRNA is a poor substrate for Cysteinyl-tRNA synthetase, which ensures low background incorporation of Cys into the chosen codon. Simultaneously, p-azidophenylalanine mediated amber-codon suppression and its post-translational conjugation to tetramethylrhodamine dibenzocyclooctyne (TAMRA-DIBO) were performed on the same polypeptide. This simple and robust approach takes advantage of the compatibility of BODIPY fluorophore with the translational machinery and thus requires only one post-translational derivatization step to introduce two fluorescent labels. Using this approach, we obtained CaM nearly homogeneously labeled with two FRET-forming fluorophores. Single molecule FRET analysis revealed dramatic changes in the conformation of the CaM probe upon its exposure to Ca or a chelating agent. The presented approach is applicable to other sense codons and can be directly transferred to eukaryotic cell-free systems.
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http://dx.doi.org/10.1021/acssynbio.6b00245DOI Listing
March 2017

Closing yield gaps in China by empowering smallholder farmers.

Nature 2016 09 7;537(7622):671-674. Epub 2016 Sep 7.

Center for Animal Health and Productivity, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, Pennsylvania 19348, USA.

Sustainably feeding the world's growing population is a challenge, and closing yield gaps (that is, differences between farmers' yields and what are attainable for a given region) is a vital strategy to address this challenge. The magnitude of yield gaps is particularly large in developing countries where smallholder farming dominates the agricultural landscape. Many factors and constraints interact to limit yields, and progress in problem-solving to bring about changes at the ground level is rare. Here we present an innovative approach for enabling smallholders to achieve yield and economic gains sustainably via the Science and Technology Backyard (STB) platform. STB involves agricultural scientists living in villages among farmers, advancing participatory innovation and technology transfer, and garnering public and private support. We identified multifaceted yield-limiting factors involving agronomic, infrastructural, and socioeconomic conditions. When these limitations and farmers' concerns were addressed, the farmers adopted recommended management practices, thereby improving production outcomes. In one region in China, the five-year average yield increased from 67.9% of the attainable level to 97.0% among 71 leading farmers, and from 62.8% to 79.6% countywide (93,074 households); this was accompanied by resource and economic benefits.
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http://dx.doi.org/10.1038/nature19368DOI Listing
September 2016

Multi-Fluorescence Real-Time PCR Assay for Detection of RIF and INH Resistance of M. tuberculosis.

Front Microbiol 2016 29;7:618. Epub 2016 Apr 29.

State Key Laboratory of Genetic Engineering, Shanghai Engineering Research Center of Industrial Microorganisms, School of Life Science, Fudan University Shanghai, China.

Background: Failure to early detect multidrug-resistant tuberculosis (MDR-TB) results in treatment failure and poor clinical outcomes, and highlights the need to rapidly detect resistance to rifampicin (RIF) and isoniazid (INH).

Methods: In Multi-Fluorescence quantitative Real-Time PCR (MF-qRT-PCR) assay, 10 probes labeled with four kinds of fluorophores were designed to detect the mutations in regions of rpoB, katG, mabA-inhA, oxyR-ahpC, and rrs. The efficiency of MF-qRT-PCR assay was tested using 261 bacterial isolates and 33 clinical sputum specimens. Among these samples, 227 Mycobacterium tuberculosis isolates were analyzed using drug susceptibility testing (DST), DNA sequencing and MF-qRT-PCR assay.

Results: Compared with DST, MF-qRT-PCR sensitivity and specificity for RIF-resistance were 94.6 and 100%, respectively. And the detection sensitivity and specificity for INH-resistance were 85.9 and 95.3%, respectively. Compared with DNA sequencing, the sensitivity and specificity of our assay were 97.2 and 100% for RIF-resistance and 97.9 and 96.4% for INH-resistance. Compared with Phenotypic strain identification, MF-qRT-PCR can distinguish 227 M. tuberculosis complexes (MTC) from 34 Non-tuberculous mycobacteria (NTM) isolates with 100% accuracy rate.

Conclusions: MF-qRT-PCR assay was an efficient, accurate, reliable, and easy-operated method for detection of RIF and INH-resistance, and distinction of MTC and NTM of clinical isolates.
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http://dx.doi.org/10.3389/fmicb.2016.00618DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4850356PMC
May 2016

Genome-Wide De Novo Prediction of Cis-Regulatory Binding Sites in Mycobacterium tuberculosis H37Rv.

PLoS One 2016 17;11(2):e0148965. Epub 2016 Feb 17.

State Key Lab of Genetic Engineering, Shanghai Engineering Research Center of Industrial Microorganisms, College of Life Sciences, Fudan University, Shanghai, PR China.

The transcription regulatory system of Mycobacterium tuberculosis (M. tb) remains incompletely understood. In this study, we have applied the eGLECLUBS algorithm to a group of related prokaryotic genomes for de novo genome-wide prediction of cis-regulatory binding sites (CRBSs) in M. tb H37Rv. The top 250 clusters from our prediction recovered 83.3% (50/60) of all known CRBSs in extracted inter-operonic sequences of this strain. We further demonstrated that the integration of our prediction results with the ChIP-Seq datasets is very effective in identifying true binding sites of TFs. Using electrophoretic mobility shift assays and real-time RT-PCR, we experimentally verified our prediction of CRBSs for Rv0081, an important transcription factor thought to be involved in regulation of M. tb under hypoxia.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0148965PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4757040PMC
July 2016

Strengthening Agronomy Research for Food Security and Environmental Quality.

Environ Sci Technol 2016 Feb 1;50(4):1639-41. Epub 2016 Feb 1.

Key Laboratory of Plant-Soil Interactions, Ministry of Education, Center for Resources, Environment and Food Security, China Agricultural University , Beijing 100193, China.

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http://dx.doi.org/10.1021/acs.est.6b00267DOI Listing
February 2016

Growing sensitivity of maize to water scarcity under climate change.

Sci Rep 2016 Jan 25;6:19605. Epub 2016 Jan 25.

College of Resources &Environmental Sciences, China Agricultural University, Beijing 100193, China.

Climate change can reduce crop yields and thereby threaten food security. The current measures used to adapt to climate change involve avoiding crops yield decrease, however, the limitations of such measures due to water and other resources scarcity have not been well understood. Here, we quantify how the sensitivity of maize to water availability has increased because of the shift toward longer-maturing varieties during last three decades in the Chinese Maize Belt (CMB). We report that modern, longer-maturing varieties have extended the growing period by an average of 8 days and have significantly offset the negative impacts of climate change on yield. However, the sensitivity of maize production to water has increased: maize yield across the CMB was 5% lower with rainfed than with irrigated maize in the 1980s and was 10% lower (and even >20% lower in some areas) in the 2000s because of both warming and the increased requirement for water by the longer-maturing varieties. Of the maize area in China, 40% now fails to receive the precipitation required to attain the full yield potential. Opportunities for water saving in maize systems exist, but water scarcity in China remains a serious problem.
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http://dx.doi.org/10.1038/srep19605DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4726359PMC
January 2016

Integration of bacterial expansin-like proteins into cellulosome promotes the cellulose degradation.

Appl Microbiol Biotechnol 2016 Mar 31;100(5):2203-12. Epub 2015 Oct 31.

Qingdao Engineering Laboratory of Single Cell Oil, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao, Shandong, 266101, China.

Cellulosomes are multi-enzyme complexes assembled by cellulases and hemicellulases through dockerin-cohesin interactions, which are the most efficient system for the degradation of lignocellulosic resources in nature. Recent genomic analysis of a cellulosome-producing anaerobe Clostridium clariflavum DSM 19732 revealed that two expansin-like proteins, Clocl_1298 and Clocl_1862, contain a dockerin module, which suggests that they are components of the cellulosome. Bacterial expansin-like proteins do not have hydrolytic activities, but can facilitate the degradation of cellulosic biomass via synergistic effects with cellulases. In this study, the synergistic effect of the expansin-like proteins with both native and designer cellulosomes was investigated. The free expansin-like proteins, including expansin-like domains of Clocl_1298 and Clocl_1862, as well as a well-studied bacterial expansin-like protein BsEXLX1 from Bacillus subtilis, promoted the cellulose degradation by native cellulosomes, indicating the cellulosomal expansin-like proteins have the synergistic function. When they were integrated into a trivalent designer cellulosome, the synergistic effect was further amplified. The sequence and structure analyses indicated that these cellulosomal expansin-like proteins share the conserved functional mechanism with other bacterial expansin-like proteins. These results indicated that non-catalytic expansin-like proteins in the cellulosome can enhance the activity of the cellulosome in lignocellulose degradation. The involvement of functional expansin-like proteins in the cellulosome also implies new physiological functions of bacterial expansin-like proteins and cellulosomes.
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http://dx.doi.org/10.1007/s00253-015-7071-6DOI Listing
March 2016
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