Publications by authors named "Liwei Gao"

44 Publications

Epidemiological characteristics and clinical manifestations of pediatric patients with COVID-19 in China: A multicenter retrospective study.

Pediatr Investig 2021 Aug 12:e12282. Epub 2021 Aug 12.

Chinese University of Hong Kong Shatin Hong Kong China.

Importance: The Coronavirus disease 2019 (COVID-19) global pandemic poses a considerable challenge for pediatricians.

Objective: This study aimed to identify the epidemiological characteristics and clinical features of pediatric patients with COVID-19 in China.

Methods: This multicenter retrospective study included pediatric patients from 46 hospitals in China, covering 12 provinces and two municipalities. Epidemiological, demographic, clinical, laboratory, treatment, and outcome data were analyzed.

Results: In total, 211 pediatric patients with COVID-19 were included in this study. The median age was 7.0 years (range: 22 days to 18 years). Approximately 16.3% of the patients exhibited asymptomatic infections, 23.0% had upper respiratory tract infections, and 60.7% had pneumonia, including two with severe pneumonia and one with critical illness. Approximately 78.7% of the pediatric patients occurred in familial clusters. The most three common symptoms or signs at onset in children with COVID-19 were fever (54.5%), cough (49.3%), and pharyngeal congestion (20.8%). Only 17.6% of the patients presented with decreased lymphocyte count, whereas 13.6% had increased lymphocyte count. Among the patients with pneumonia who exhibited abnormal chest computed tomography findings, 18.2% (23/127) of the patients had no other symptoms. Generally, the chest radiographs showed abnormalities that affected both lungs (49.6%); ground-glass opacity (47.2%) was the most common manifestation. The cure and improvement rates were 86.7% (183/211) and 13.3% (28/211), respectively. Only one patient with an underlying condition received invasive mechanical ventilation; none of the patients died.

Interpretation: Similar to adults, children of all age groups are susceptible to COVID-19. Fortunately, most pediatric patients have mild symptoms or remain asymptomatic, despite the high incidence of pneumonia. Decreased proportions of white blood cells and lymphocytes are less frequent in children than in adults.
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http://dx.doi.org/10.1002/ped4.12282DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8441896PMC
August 2021

Functional analysis of the transcriptional activator XlnR of Penicillium oxalicum.

J Appl Microbiol 2021 Aug 31. Epub 2021 Aug 31.

State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong Province, China.

Aims: The aim of this article is to study the functional features of Penicillium oxalicum transcriptional activator XlnR.

Methods And Results: The yeast reporter system was used to identify transcriptional activation domain of XlnR in P. oxalicum. The expression cassette was introduced into the xlnR locus of P. oxalicum by homologous recombination. In this study, several putative structural domains in P. oxalicum XlnR were predicted by bioinformatics analysis, and the transcriptional activation domain (351-694 region) was identified in XlnR relying on reporter gene system in yeast. In addition, the amino acid at XlnR 871 site (alanine) located in the regulatory region could influence the regulatory activity of XlnR directly. When the alanine at XlnR 871 site was replaced by stronger hydrophobic amino acid (e.g. valine or isoleucine), the regulatory activity will be greatly improved, especially for the regulation of hemicellulase genes expression. When alanine at XlnR 871 site was mutated to a hydrophilic amino acid (e.g. aspartic acid or arginine), the regulatory activity of XlnR will be reduced.

Conclusions: The 351-694 region of P. oxalicum XlnR was identified as transcriptional activation domain, and the regulatory activity of XlnR was greatly influenced by hydrophobicity of amino acid at 871 site of XlnR in P. oxalicum.

Significance And Impact Of The Study: The results will provide an effective target site to regulate the activity of XlnR and improve cellulase production of P. oxalicum.
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http://dx.doi.org/10.1111/jam.15276DOI Listing
August 2021

Compound heterozygous DCLRE1C mutations lead to clinically typical Severe Combined Immunodeficiency presenting with Graft Versus Host Disease.

Immunogenetics 2021 Aug 18. Epub 2021 Aug 18.

Laboratory of Tumor Immunology, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China.

Artemis (DCLRE1C) is involved in opening recombination-activating gene (RAG1/RAG2)-generated hairpins during V(D)J recombination, an essential process for the differentiation and maturation of T and B cells. Here, we reported a case of 5-month-old boy with recurrent respiratory infections, disseminated Bacille Calmette-Guérin (BCG) infection, generalized erythroderma, hepatosplenomegaly, lymphadenopathy, eosinophillia and failure to thrive, symptoms often observed in Omenn syndrome. Genetic analysis revealed compound heterozygous mutations of the DCLRE1C gene, including deletions of exons 1 and 2, and a c. 352G>T (p. G118X) nonsense mutation in exon 5. Flow cytometry analysis of the patient PBMCs indicated a TBNK immunophenotype. Short tandem repeat (STR) analysis confirmed transplacental maternal lymphocytes engraftment in circulating blood of the patient. Collectively, we reported a patient showing atypical immunophenotypic and typical clinical presentations of Severe Combined Immunodeficiency (SCID) with Graft Versus Host Disease (GVHD) in the context of compound heterozygous mutations of the DCLRE1C gene. This study adds to the ever-growing knowledge on the broad immunological and clinical spectrum associated with DCLRE1C mutations.
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http://dx.doi.org/10.1007/s00251-021-01219-4DOI Listing
August 2021

Adsorption of Hg(II) in solution by mercaptofunctionalized palygorskite.

Environ Sci Pollut Res Int 2021 Jul 31. Epub 2021 Jul 31.

Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, No. 9 Wenyuan Road, Yadong New District, Nanjing, 210023, China.

In the past 10 years, the treatment and restoration of soil and water bodies contaminated by mercury and other heavy metals have received unprecedented attention and support from China's environmental protection authorities. The search for low-cost and high-efficiency adsorbents has become one of the research hotspots in this field. In this paper, a simple and environment-friendly method was used to graft 3-mercaptopropyl trimethoxysilane on the surface of palygorskite. The synthesized mercaptofunctionalized palygorskite (M-PAL) was characterized by XRD, FT-IR, BET and SEM-EDS, respectively, and its adsorption conditions, adsorption models and thermodynamic parameters for Hg were systematically investigated. The experimental results indicated that the saturated adsorption capacity of Hg on the M-PAL could reach 203.4 mg·g, within 120 min at pH 4 and 298 K. By analyzing the experimental data of adsorption kinetics and thermodynamics, it was found that the adsorption process of Hg conformed to the pseudo-second-order kinetic model, which belonged to chemical adsorption of the rate-controlled step; the Langmuir model better described the adsorption isotherm. The thermodynamic parameters obtained (ΔH=29.95 kJ·mol, ΔS=103.09 J·mol·K and ΔG<0) show that the whole process is a spontaneous endothermic process. When the concentration of Na, K, Ca, Mg, Cl, NO, HCO and CHO was 200 times that of Hg, although these organic acids had a slightly greater effect on the adsorption of Hg on mercaptofunctionalized palygorskite than inorganic ions, the adsorption capacity remained above 185 mg·g. The adsorption products could be still stable in simulated acid rain with pH 3, 4, 5, 6, 7 and oxalic acid solution with concentration of 1, 2, 3, 4 and 5 mmol·L, and the desorption rates were about 3%. Through XPS analysis, the specific coordination of Hg with the S atom on the surface of M-PAL was confirmed.
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http://dx.doi.org/10.1007/s11356-021-15637-0DOI Listing
July 2021

Comparison of Clinical Characteristics Among COVID-19 and Non-COVID-19 Pediatric Pneumonias: A Multicenter Cross-Sectional Study.

Front Cell Infect Microbiol 2021 1;11:663884. Epub 2021 Jul 1.

Department of Pediatrics, Yichang Central People's Hospital, Yichang, China.

Background: The pandemic of Coronavirus Disease 2019 (COVID-19) brings new challenges for pediatricians, especially in the differentiation with non-COVID-19 pneumonia in the peak season of pneumonia. We aimed to compare the clinical characteristics of pediatric patients with COVID-19 and other respiratory pathogens infected pneumonias.

Methods: We conducted a multi-center, cross-sectional study of pediatric inpatients in China. Based on pathogenic test results, pediatric patients were divided into three groups, including COVID-19 pneumonia group, Non-COVID-19 viral (NCV) pneumonia group and Non-viral (NV) pneumonia group. Their clinical characteristics were compared by Kruskal-Wallis H test or chi-square test.

Results: A total of 636 pediatric pneumonia inpatients, among which 87 in COVID-19 group, 194 in NCV group, and 355 in NV group, were included in analysis. Compared with NCV and NV patients, COVID-19 patients were older (median age 6.33, IQR 2.00-12.00 years), and relatively fewer COVID-19 patients presented fever (63.2%), cough (60.9%), shortness of breath (1.1%), and abnormal pulmonary auscultation (18.4%). The results were verified by the comparison of COVID-19, respiratory syncytial virus (RSV) and influenza A (IFA) pneumonia patients. Approximately 42.5%, 44.8%, and 12.6% of the COVID-19 patients presented simply ground-glass opacity (GGO), simply consolidation, and the both changes on computed tomography (CT) scans, respectively; the proportions were similar as those in NCV and NV group (p>0.05). Only 47.1% of COVID-19 patients had both lungs pneumonia, which was significantly lower than that proportion of nearly 80% in the other two groups. COVID-19 patients presented lower proportions of increased white blood cell count (16.5%) and abnormal procalcitonin (PCT) (10.7%), and a higher proportion of decreased lymphocyte count (44.0%) compared with the other two groups.

Conclusion: Majority clinical characteristics of pediatric COVID-19 pneumonia patients were milder than non-COVID-19 patients. However, lymphocytopenia remained a prominent feature of COVID-19 pediatric pneumonia.
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http://dx.doi.org/10.3389/fcimb.2021.663884DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8281119PMC
July 2021

A clinicopathologic analysis of microscopic extension in small cell lung cancer and lung adenocarcinoma: Determination of clinical target volume with precise radiotherapy.

Thorac Cancer 2021 07 24;12(13):1973-1982. Epub 2021 May 24.

Department of Radiation Oncology, Peking University First Hospital, Beijing, China.

Purpose: The identification of the clinical target volume (CTV) is particularly important in the precise radiotherapy of lung cancer. The purpose of this study was to determine the extension margin from gross tumor volume (GTV) to CTV in primary small cell lung cancer (SCLC) and lung adenocarcinoma (ADC) by microscopic extension (ME).

Material And Methods: The data of 25 cases of SCLC and 29 cases of ADC from August 2015 to August 2020 were analyzed. The measurement of tumor size between preoperative thoracic computed tomography (CT) and postoperative macroscopic specimens was compared, and the ME range of tumor cells was measured under a microscope to determine its correlation with clinical features and pathological manifestations.

Results: A total of 217 slides were examined, corresponding to 103 slides for SCLC and 114 slides for ADC. The radiologic sizes of the tumors in SCLC and ADC were 12.8 and 7.9 mm, respectively (p = 0.09), and the macroscopic sizes were 12.5 and 8.5 mm, respectively (p = 0.07). There was a significant correlation between the radiologic and macroscopic size of the same tumor sample (r = 0.886). Compared with ADC, more SCLC tumor cells infiltrated through vascular or lymphatic dissemination (16% vs. 9%, p = 0.047). The mean ME value was 2.81 mm for SCLC and 2.02 mm for ADC (p = 0.012). To take into account 95% of the ME, a margin of 8 and 7.7 mm must be expanded for SCLC and ADC, respectively. The ME value of the tumor was related to the presence of atelectasis, the location of the tumor, and the Ki-67 cell proliferation index.

Conclusion: The GTV of the tumor was contoured according to CT images, which was basically consistent with the actual tumor size. The GTVs of SCLC and ADC should be expanded by 8 and 7.7 mm, respectively, to fully cover the subclinical lesions in 95% of cases.
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http://dx.doi.org/10.1111/1759-7714.14000DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8258354PMC
July 2021

[Progress in the production of lignocellulolytic enzyme systems using Penicillium species].

Sheng Wu Gong Cheng Xue Bao 2021 Mar;37(3):1058-1069

State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao 266237, Shandong, China.

The efficient production of lignocellulolytic enzyme systems is an important support for large-scale biorefinery of plant biomass. On-site production of lignocellulolytic enzymes could increase the economic benefits of the process by lowering the cost of enzyme usage. Penicillium species are commonly found lignocellulose-degrading fungi in nature, and have been used for industrial production of cellulase preparations due to their abilities to secrete complete and well-balanced lignocellulolytic enzyme systems. Here, we introduce the reported Penicillium species for cellulase production, summarize the characteristics of their enzymes, and describe the strategies of strain engineering for improving the production and performance of lignocellulolytic enzymes. We also review the progress in fermentation process optimization regarding the on-site production of lignocellulolytic enzymes using Penicillium species, and suggest prospect of future work from the perspective of building a "sugar platform" for the biorefinery of lignocellulosic biomass.
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http://dx.doi.org/10.13345/j.cjb.200531DOI Listing
March 2021

Efficient Constitutive Expression of Cellulolytic Enzymes in for Improved Efficiency of Lignocellulose Degradation.

J Microbiol Biotechnol 2021 May;31(5):740-746

State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China.

Efficient cellulolytic enzyme production is important for the development of lignocellulose-degrading enzyme mixtures. However, purification of cellulases from their native hosts is time- and labor-consuming. In this study, a constitutive expression system was developed in for the secreted production of proteins. Using a constitutive polyubiquitin gene promoter and cultivating with glucose as the sole carbon source, nine cellulolytic enzymes of different origins with relatively high purity were produced within 48 h. When supplemented to a commercial cellulase preparation, cellobiohydrolase I from and cellobiohydrolase II from showed remarkable enhancing effects on the hydrolysis of steam-exploded corn stover. Additionally, a synergistic effect was observed for these two cellobiohydrolases during the hydrolysis. Taken together, the constitutive expression system provides a convenient tool for the production of cellulolytic enzymes, which is expected to be useful in the development of highly efficient lignocellulose-degrading enzyme mixtures.
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http://dx.doi.org/10.4014/jmb.2101.01003DOI Listing
May 2021

Disruption of the Trichoderma reesei gul1 gene stimulates hyphal branching and reduces broth viscosity in cellulase production.

J Ind Microbiol Biotechnol 2021 Apr;48(1-2)

State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, 266237 Qingdao, China.

Hyphal morphology is considered to have a close relationship with the production level of secreted proteins by filamentous fungi. In this study, the gul1 gene, which encodes a putative mRNA-binding protein, was disrupted in cellulase-producing fungus Trichoderma reesei. The hyphae of Δgul1 strain produced more lateral branches than the parent strain. Under the condition for cellulase production, disruption of gul1 resulted in smaller mycelial clumps and significantly lower viscosity of fermentation broth. In addition, cellulase production was improved by 22% relative to the parent strain. Transcriptome analysis revealed that a set of genes encoding cell wall remodeling enzymes as well as hydrophobins were differentially expressed in the Δgul1 strain. The results suggest that the regulatory role of gul1 in cell morphogenesis is likely conserved in filamentous fungi. To our knowledge, this is the first report on the engineering of gul1 in an industrially important fungus.
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http://dx.doi.org/10.1093/jimb/kuab012DOI Listing
April 2021

Combinatorial Engineering of Transcriptional Activators in for Improved Production of Corn-Fiber-Degrading Enzymes.

J Agric Food Chem 2021 Mar 23;69(8):2539-2548. Epub 2021 Feb 23.

State Key Laboratory of Microbial Technology, Shandong University, 72 Binhai Road, 266237 Qingdao, China.

Enzymatic conversion of corn fiber to fermentable sugars is beneficial to improving the economic efficiency of corn processing. In this work, the filamentous fungus was found to secrete enzymes for efficient saccharification of un-pretreated corn fiber. Separate engineering of transcriptional activators ClrB, XlnR, and AraR led to enhanced production of different sets of lignocellulolytic enzymes. Particularly, the enzymes produced by XlnR- and AraR-engineered strains showed a synergistic effect in corn fiber saccharification. Combinatorial engineering of all three activators generated a strain MCAX with 3.1- to 51.0-fold increases in lignocellulolytic enzyme production compared with the parent strain. In addition, the enzymes of strain MCAX released significantly more fermentable sugars from corn fiber than those of the parent strain at the same protein dosage. The results suggest that this strain has potential for on-site production of enzymes for corn fiber saccharification.
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http://dx.doi.org/10.1021/acs.jafc.0c07659DOI Listing
March 2021

Stink bean () empty pod: a potent natural antidiabetic agent for the prevention of pancreatic and hepatorenal dysfunction in high fat diet/streptozotocin-induced type 2 diabetes in rats.

Arch Physiol Biochem 2021 Jan 31:1-7. Epub 2021 Jan 31.

Faculty of Thai Traditional Medicine, Prince of Songkla University, Hat Yai, Thailand.

The present study investigated the effect of polyphenol-rich extract of (PPS) against pancreatic and hepatorenal dysfunction in high-fat diet (HFD)/streptozotocin (STZ)-induced diabetes. Diabetic rats were treated with PPS (100 and 400 mg/kg) and glibenclamide. The results revealed that diabetic rats displayed marked hyperglycaemia, hyperlipidaemia, hypoinsulinemia as well as alterations in serum renal and kidney function markers. Furthermore, diabetic rats showed significant increase in hepatorenal level of malonaldehyde as well as suppression of antioxidant enzyme activities. Whereas, diabetic rats that received PPS displayed marked attenuation in most of the aforementioned parameters compared to the untreated diabetic rats. Additionally, histological examination revealed restoration of histopathological alterations of the pancreas, liver, and kidney of PPS treated diabetic rats. In conclusion, the results demonstrated that PPS could decrease serum lipids and blood glucose level, enhance insulin level and hepatorenal antioxidant capacity, as well as ameliorate hepatorenal dysfunction in rats.
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http://dx.doi.org/10.1080/13813455.2021.1876733DOI Listing
January 2021

CRISPR/Cas9-mediated genome editing in Penicillium oxalicum and Trichoderma reesei using 5S rRNA promoter-driven guide RNAs.

Biotechnol Lett 2021 Feb 13;43(2):495-502. Epub 2020 Oct 13.

State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, 27 Binhai Road, Qingdao, 266237, China.

Objective: To construct convenient CRISPR/Cas9-mediated genome editing systems in industrial enzyme-producing fungi Penicillium oxalicum and Trichoderma reesei.

Results: Employing the 5S rRNA promoter from Aspergillus niger for guide RNA expression, the β-glucosidase gene bgl2 in P. oxalicum was deleted using a donor DNA carrying 40-bp homology arms or a donor containing no selectable marker gene. Using a markerless donor DNA as editing template, precise replacement of a small region was achieved in the creA gene. In T. reesei, the A. niger 5S rRNA promoter was less efficient than that in P. oxalicum when used for gene editing. Using a native 5S rRNA promoter, stop codons were introduced into the lae1 coding region using a markerless donor DNA with an editing efficiency of 36.67%.

Conclusions: Efficient genome editing systems were developed in filamentous fungi P. oxalicum and T. reesei by using heterologous or native 5S rRNA promoters for guide RNA expression.
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http://dx.doi.org/10.1007/s10529-020-03024-7DOI Listing
February 2021

Correlation Analysis of Expression Profile and Quantitative iTRAQ-LC-MS/MS Proteomics Reveals Resistance Mechanism Against TuMV in Chinese Cabbage ( ssp. ).

Front Genet 2020 20;11:963. Epub 2020 Aug 20.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China.

The arms race between plants and viruses never ceases. Chinese cabbage, an important type of vegetable crop, is vulnerable to plant virus infection, especially to (TuMV). To better examine the molecular mechanisms behind the virus infection, we conducted the correlation analysis of RNA-Seq and quantitative iTRAQ-LC-MS/MS in TuMV-infected and in healthy Chinese cabbage leaves. There were 757 differentially expressed genes and 75 differentially expressed proteins that were screened in Chinese cabbage plants infected with TuMV. These genes were enriched in many pathways, and among them, the plant hormone signal transduction, plant-pathogen interaction, and protein processing in the endoplasmic reticulum pathways were suggested to be closely related pathways. The correlation analysis between RNA-Seq and quantitative iTRAQ-LC-MS/MS was then further explored. Finally, we obtained a preliminary network of several candidate genes associated with TuMV infection, and we found that they mainly belonged to calcium signaling pathways, heat shock proteins, WRKY transcription factors, and non-specific lipid transfer proteins. These results may lead to a better understanding of antiviral mechanisms and of disease-resistant breeding.
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http://dx.doi.org/10.3389/fgene.2020.00963DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7469979PMC
August 2020

A calmodulin-like CmCML13 from Cucumis melo improved transgenic Arabidopsis salt tolerance through reduced shoot's Na, and also improved drought resistance.

Plant Physiol Biochem 2020 Oct 2;155:271-283. Epub 2020 Aug 2.

School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, PR China. Electronic address:

The calmodulin-like proteins (CMLs) are a large family involved in plant biological processes. A calmodulin-like gene CmCML13 (GenBank accession number: MT340534) from melon (Cucumis melo L.) was isolated and functionally analyzed. CmCML13 was predicted to possess 3 EF-hands in which only the first EF-hand could bind with Ca. Subcellular localization assay revealed that CmCML13 was localized in nucleus, cell membrane, vacuolar membrane and cytoplasmic strand. The transcript level of CmCML13 was temporally and spatially regulated under salt stress. Constitutive expression of CmCML13 in the Arabidopsis thaliana enhanced salt tolerance at seeds germination. CmCML13 improved the transgenic Arabidopsis plants salt tolerance by significantly reducing Na content of shoots, which was unrelated to HKT1-involving pathway. Moreover, overexpressing of CmCML13 in Arabidopsis showed stronger drought tolerance. This study demonstrates that the CmCML13 is an important multifunctional protein associated with salt and drought stress, which may play a key role in stress signaling pathway.
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http://dx.doi.org/10.1016/j.plaphy.2020.07.013DOI Listing
October 2020

Diagnosis, treatment, and prevention of 2019 novel coronavirus infection in children: experts' consensus statement.

World J Pediatr 2020 06 7;16(3):223-231. Epub 2020 Feb 7.

Department of Respiratory Medicine, Beijing Children's Hospital, Capital Medical University, Beijing, China.

Since the outbreak of 2019 novel coronavirus infection (2019-nCoV) in Wuhan City, China, by January 30, 2020, a total of 9692 confirmed cases and 15,238 suspected cases have been reported around 31 provinces or cities in China. Among the confirmed cases, 1527 were severe cases, 171 had recovered and been discharged at home, and 213 died. And among these cases, a total of 28 children aged from 1 month to 17 years have been reported in China. For standardizing prevention and management of 2019-nCoV infections in children, we called up an experts' committee to formulate this experts' consensus statement. This statement is based on the Novel Coronavirus Infection Pneumonia Diagnosis and Treatment Standards (the fourth edition) (National Health Committee) and other previous diagnosis and treatment strategies for pediatric virus infections. The present consensus statement summarizes current strategies on diagnosis, treatment, and prevention of 2019-nCoV infection in children.
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http://dx.doi.org/10.1007/s12519-020-00343-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7090771PMC
June 2020

Conjunctive Analyses of BSA-Seq and BSR-Seq to Reveal the Molecular Pathway of Leafy Head Formation in Chinese Cabbage.

Plants (Basel) 2019 Dec 13;8(12). Epub 2019 Dec 13.

Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.

As the storage organ of Chinese cabbage, the leafy head was harvested as a commercial product due to its edible value. In this study, the bulked segregant analysis (BSA) and bulked segregant RNA-Seq (BSR) were performed with F separation progeny to study the molecular mechanism of leafy head formation in Chinese cabbage. BSA-Seq analysis located four candidate regions containing 40 candidate genes, while BSR-Seq analysis revealed eight candidate regions containing 607 candidate genes. The conjunctive analyses of these two methods identified that Casein kinase gene () is the common candidate gene related with leafy head formation in Chinese cabbage, and it showed high expression levels at the three segments of heading type plant leaves. The differentially expressed genes (DEGs) between two set pairs of cDNA sequencing bulks were divided into two categories: one category was related with five hormone pathways (Auxin, Ethylene, Abscisic acid, Jasmonic acid and Gibberellin), the other category was composed of genes that associate with the calcium signaling pathway. Moreover, a series of upregulated transcriptional factors (TFs) were also identified by the association analysis of BSR-Seq analysis. The leafy head development was regulated by various biological processes and effected by diverse external environment factors, so our research will contribute to the breeding of perfect leaf-heading types of Chinese cabbage.
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http://dx.doi.org/10.3390/plants8120603DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6963953PMC
December 2019

The Role of Cross-Pathway Control Regulator CpcA in the Growth and Extracellular Enzyme Production of Penicillium oxalicum.

Curr Microbiol 2020 Jan 7;77(1):49-54. Epub 2019 Nov 7.

State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao, 266237, Shandong, People's Republic of China.

CpcA is a conserved transcriptional activator for the cross-pathway control of amino acid biosynthetic genes in filamentous fungi. Previous studies of this regulator mainly revealed its function under amino acid starvation condition, where amino acid biosynthetic inhibitors were added in the culture. In this study, the biological function of CpcA in Penicillium oxalicum was investigated under different cultivation conditions. Disruption of cpcA led to decreased cell growth either in the presence or absence of histidine biosynthetic inhibitor, and the phenotype could be rescued by the addition of exogenous amino acid sources. In addition, CpcA was required for the rapid production of cellulase when cells were cultured on cellulose. Transcript abundance measurement showed that a set of amino acid biosynthetic genes as well as two major cellulase genes were significantly down-regulated in cpcA deletion mutant relative to wild type. Taken together, the results revealed the biological role of CpcA in supporting normal growth and extracellular enzyme production of P. oxalicum under amino acid non-starvation condition.
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http://dx.doi.org/10.1007/s00284-019-01803-8DOI Listing
January 2020

Deletion of the middle region of the transcription factor ClrB in enables cellulase production in the presence of glucose.

J Biol Chem 2019 12 28;294(49):18685-18697. Epub 2019 Oct 28.

State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, China.

Enzymes that degrade lignocellulose to simple sugars are of great interest in research and for biotechnology because of their role in converting plant biomass to fuels and chemicals. The synthesis of cellulolytic enzymes in filamentous fungi is tightly regulated at the transcriptional level, with the transcriptional activator ClrB/CLR-2 playing a critical role in many species. In , overexpression could not relieve the dependence of cellulase expression on cellulose as an inducer, suggesting that is controlled post-transcriptionally. In this study, using a reporter gene system in yeast, we identified the C-terminal region of ClrB/CLR-2 as a transcriptional activation domain. Expression of , encoding a ClrB derivative in which the DNA-binding and transcriptional activation domains are fused together to remove the middle region, led to cellulase production in the absence of cellulose in Strikingly, the -expressing strain produced cellulase on carbon sources that normally repress cellulase expression, including glucose and glycerol. Results from deletion of the carbon catabolite repressor gene in the -expressing strain suggested that the effect of is independent of CreA's repressive function. A similar modification of in resulted in the production of a mannanase in glucose medium. Taken together, these results indicate that ClrB suppression under noninducing conditions involves its middle region, suggesting a potential strategy to engineer fungal strains for improved cellulase production on commonly used carbon sources.
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http://dx.doi.org/10.1074/jbc.RA119.010863DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6901314PMC
December 2019

Transcription Coactivator ANGUSTIFOLIA3 (AN3) Regulates Leafy Head Formation in Chinese Cabbage.

Front Plant Sci 2019 30;10:520. Epub 2019 Apr 30.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, China.

Leafy head formation in Chinese cabbage ( ssp. cv. Bre) results from leaf curvature, which is under the tight control of genes involved in the adaxial-abaxial patterning during leaf development. The transcriptional coactivator ANGUSTIFOLIA3 (AN3) binds to the SWI/SNF chromatin remodeling complexes formed around ATPases such as BRAHMA (BRM) in order to regulate transcription in various aspects of leaf development such as cell proliferation, leaf primordia expansion, and leaf adaxial/abaxial patterning in Arabidopsis. However, its regulatory function in Chinese cabbage remains poorly understood. Here, we analyzed the expression patterns of the Chinese cabbage gene () before and after leafy head formation, and produced gene silencing plants by using the turnip yellow mosaic virus (TYMV)-derived vector in order to explore its potential function in leafy head formation in Chinese cabbage. We found that had distinct expression patterns in the leaves of Chinese cabbage at the rosette and heading stages. We also found silencing of stimulated leafy head formation at the early stage. Transcriptome analysis indicated that silencing of modulated the hormone signaling pathways of auxin, ethylene, GA, JA, ABA, BR, CK, and SA in Chinese cabbage. Our study offers unique insights into the function of in leafy head formation in Chinese cabbage.
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http://dx.doi.org/10.3389/fpls.2019.00520DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6502973PMC
April 2019

Corrigendum to "FoxO1-mediated autophagy plays an important role in the neuroprotective effects of hydrogen in a rat model of vascular dementia" [Behav. Brain Res. 356 (2019) 98-106].

Behav Brain Res 2019 Nov 18;374:111839. Epub 2019 Apr 18.

Department of Neurology, Hebei Medical University, No. 361 Zhongshan East Road, Changan District, Shijiazhuang, 050017, Hebei Province, People's Republic of China; Department of Neurology, Hebei General Hospital, No. 348 Heping West Road, Xinhua District, Shijiazhuang, 050051, Hebei Province, People's Republic of China. Electronic address:

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http://dx.doi.org/10.1016/j.bbr.2019.03.008DOI Listing
November 2019

Mutation of a Conserved Alanine Residue in Transcription Factor AraR Leads to Hyperproduction of α-l-Arabinofuranosidases in Penicillium oxalicum.

Biotechnol J 2019 Jul 15;14(7):e1800643. Epub 2019 Apr 15.

State Key Laboratory of Microbial Technology, Shandong University, 27 Binhai Road, 266237, Qingdao, China.

α-l-Arabinofuranosidases are important in the degradation of plant polysaccharides and are used in several industrial processes. Although the use of filamentous fungi for the production of α-l-arabinofuranosidases is widely reported, there are few reports on strain engineering for enhanced production of these enzymes by fungi. In this study, the function of transcription factor AraR in l-arabinose release and catabolism by the fungus Penicillium oxalicum (P. oxalicum) is investigated. Also, a mutant of AraR, AraR , is constructed to improve the production of α-l-arabinofuranosidases on the basis of the sequence homology between AraR and the xylanolytic gene activator XlnR. The AraR -overexpressing strain can synthesize α-l-arabinofuranosidase in the absence of an inducer and shows a 54.1-fold increase in α-l-arabinofuranosidase production and a 7.4-fold increase in α-galactosidase production in the medium containing wheat bran. Determination of the transcript abundances of lignocellulolytic enzyme genes reveals significant upregulation of multiple α-l-arabinofuranosidase genes and downregulation of some cellulolytic and xylanolytic enzyme genes in the engineered strain relative to its parent. Taken together, the results suggest the conserved regulatory function of AraR in the family Trichocomaceae and provide a strategy for engineering fungal strains for enhanced α- l-arabinofuranosidase production.
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http://dx.doi.org/10.1002/biot.201800643DOI Listing
July 2019

Introduction of heterologous transcription factors and their target genes into Penicillium oxalicum leads to increased lignocellulolytic enzyme production.

Appl Microbiol Biotechnol 2019 Mar 5;103(6):2675-2687. Epub 2019 Feb 5.

State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, Shandong Province, China.

Genetic engineering of transcription factors is an efficient strategy to improve lignocellulolytic enzyme production in fungi. In this study, the xylanase transcriptional regulators of Trichoderma reesei (Xyr1) and Neurospora crassa (XLR-1), as well as their constitutively active mutants (Xyr1 and XLR-1), were heterologously expressed in Penicillium oxalicum. The two heterologous regulators were identified to be able to activate lignocellulolytic enzyme gene expression in P. oxalicum. Particularly, expression of T. reesei Xyr1 resulted in a higher cellulase production level compared with the expression of native xylanase transcriptional regulator XlnR using the same promoter. Xyr1 and XLR-1 were found to be able to confer P. oxalicum more enhanced lignocellulolytic abilities than wild-type regulators Xyr1 and XLR-1. Furthermore, introduction of regulatory modules containing Xyr1/XLR-1 and their target cellulase genes resulted in greater increases in cellulase production than alone expression of transcriptional regulators. Through the cumulative introduction of three regulatory modules containing regulator mutants and their corresponding target cellulase genes from P. oxalicum, T. reesei, and N. crassa, a 2.8-fold increase in cellulase production was achieved in P. oxalicum.
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http://dx.doi.org/10.1007/s00253-018-09612-yDOI Listing
March 2019

PTEN downregulates WD repeat‑containing protein 66 in salivary adenoid cystic carcinoma.

Oncol Rep 2019 Mar 13;41(3):1827-1836. Epub 2018 Dec 13.

Department of Oral Pathology, Dental School, Dalian Medical University, Dalian, Liaoning 116044, P.R. China.

Salivary adenoid cystic carcinoma (SACC) is one of the most common types of salivary gland cancer that causes substantial morbidity and mortality. Despite the substantial health burden of SACC, the molecular mechanisms underlying its development and progression remain poorly understood. We previously reported the loss of phosphatase and tensin homolog (PTEN) expression to be common among SACC tumors, and the PTEN deficiency to be correlated with enrichment of epithelial‑mesenchymal transition (EMT) genes based on expression array analysis. The aim of the present study was to investigate further the functional function of WD repeat‑containing protein 66 (WDR66), one of the enriched EMT genes, in the context of PTEN deficiency and SACC pathogenesis. WDR66 was identified to be required to maintain the EMT phenotype and the expression of cancer stem cell genes in the context of PTEN deficiency. Furthermore, knockdown of WDR66 decreased cellular proliferation, migration and invasion. Finally, WDR66 expression was identified to be inversely associated with PTEN expression and negatively correlated with the overall survival of patients with SACC. Collectively, the results of the present study revealed a novel function of WDR66 in mediating the progression of PTEN‑deficient SACCs, thereby suggesting WDR66 inhibition to be a potential therapeutic approach towards successful management of SACC disease progression, particularly against tumors with decreased PTEN expression levels.
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http://dx.doi.org/10.3892/or.2018.6931DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6365686PMC
March 2019

Low-dose versus high-dose methylprednisolone for children with severe pneumonia (MCMP): Study protocol for a randomized controlled trial.

Pediatr Investig 2018 Sep 17;2(3):176-183. Epub 2018 Oct 17.

China National Clinical Research Center for Respiratory Diseases Department of Respiratory Medicine Beijing Children's Hospital Capital Medical University, National Center for Children's Health Beijing China.

Background: Severe pneumonia (MPP) may develop with long-term pulmonary outcomes despite treatment with macrolides. Combined treatment with glucocorticoids can improve this outcome, though the optimal dosage is unknown. The aim of this study was to investigate the effects of low- and high-dose methylprednisolone in reducing the percentage of long-term pulmonary outcomes for children with severe MPP.

Methods: A randomized, single-blind, parallel-controlled, multicenter clinical trial, methylprednisolone for children with severe pneumonia (MCMP), is being conducted in China. Pediatric patients (≤18 years of age, expected number = 402) admitted to the hospital with a clinical diagnosis of severe MPP and fulfilling inclusion and exclusion criteria are randomized (ratio of 1:1) to either a low-dose (2 mg/kg/d) or high-dose (10 mg/kg/d) methylprednisolone treatment group for 3 days followed by tapering of methylprednisolone over 12 days and combined with azithromycin. The primary composite outcome will be incidence of atelectasis, bronchiectasis, or bronchiolitis obliterans at 6-months after treatment. Secondary outcomes include recovery time of patient temperature, proportion of pulmonary lesions absorbed, changes of mucosa identified by bronchoscopy, length of hospital stay, pulmonary function and number of participant(s) needing intensive care. Assessments will be made at baseline, post-treatment and at 1-month, 3-month and 6-month follow-ups.

Discussion: This is the first randomized clinical trial designed to evaluate the safety and efficacy of low- versus high-dose methylprednisolone for reducing long-term pulmonary outcomes in pediatric patients with severe MPP. The results of this study will provide scientific evidence to guide clinical practice for the treatment of severe MPP. Trial registration: This study is registered at ClinicalTrials.gov (NCT02303587).
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http://dx.doi.org/10.1002/ped4.12041DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7331410PMC
September 2018

Cooperation Between Pten and Smad4 in Murine Salivary Gland Tumor Formation and Progression.

Neoplasia 2018 08 27;20(8):764-774. Epub 2018 Jun 27.

Department of Otolaryngology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Laboratory of Precision Oncology, School of Pharmacy, China Medical University, Shenyang, Liaoning, China; Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA. Electronic address:

Salivary gland tumor (SGT) is a rare tumor type, which exhibits broad-spectrum phenotypic, biological, and clinical heterogeneity. Currently, the molecular mechanisms that cause SGT pathogenesis remain poorly understood. A lack of animal models that faithfully recapitulate the naturally occurring process of human SGTs has hampered research progress on this field. In this report, we developed an inducible keratin 5-driven conditional knockout mouse model to delete gene(s) of interest in murine salivary gland upon local RU486 delivery. We have deleted two major tumor suppressors, Pten, a negative regulator of the PI3K pathway, and Smad4, the central signaling mediator of TGFβ pathway, in the murine salivary gland. Our results have shown that deletion of either Pten or Smad4 in murine salivary gland resulted in pleomorphic adenomas, the most common tumor in human SGT patients. Deletion of both Pten and Smad4 in murine salivary gland developed several malignancies, with salivary adenoid cystic carcinoma (SACC) being the most frequently seen. Molecular characterization showed that SACC exhibited mTOR activation and TGFβ1 overexpression. Examination of human SGT clinical samples revealed that loss of Pten and Smad4 is common in human SACC samples, particularly in the most aggressive solid form, and is correlated with survival of SACC patients, highlighting the human relevance of the murine models. In summary, our results offer significant insight into synergistic role of Pten and Smad4 in SGT, providing a rationale for targeting mTOR and/or TGFβ signaling to control SGT formation and progression.
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http://dx.doi.org/10.1016/j.neo.2018.05.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6031150PMC
August 2018

FoxO1-mediated autophagy plays an important role in the neuroprotective effects of hydrogen in a rat model of vascular dementia.

Behav Brain Res 2019 01 7;356:98-106. Epub 2018 Jun 7.

Department of Neurology, Hebei Medical University, No. 361 Zhongshan East Road, Changan District, Shijiazhuang 050017, Hebei Province, People's Republic of China; Department of Neurology, Hebei General Hospital, No. 348 Heping West Road, Xinhua District, Shijiazhuang 050051, Hebei Province, People's Republic of China. Electronic address:

Vascular dementia (VD) is a heterogeneous group of brain disorders in which cognitive impairment is attributed to cerebrovascular pathologies. Autophagy, a self-cannibalization mechanism, has been demonstrated to be involved in VD progression. Molecular hydrogen is known for its powerful anti-oxidative, anti-apoptotic, and anti-inflammatory activities, and it is also involved in autophagy. However, the effects of hydrogen on VD remain unclear. The current study found that hydrogen-rich water (HRW) significantly alleviated spatial learning and memory impairments. Similar to donepezil treatment, HRW also inhibited neuron loss and shrinkage in the hippocampal CA1 region. In addition, we found that HRW significantly increased the Bcl-2/Bax expression ratio and decreased cleaved caspase-3 expression levels in the hippocampus of VD rats. Moreover, electron microscopy revealed that HRW decreased the number of autophagosomes. We also observed that HRW reduced the increased ratio of LC3-II/I and Beclin 1 expression and saliently upregulated p62 expression. Furthermore, FoxO1 (a major mediator of autophagy regulation) and Atg7 levels were apparently decreased in the hippocampus of HRW-treated bilateral common carotid artery occlusion (2VO) rats. Taken together, these data show that molecular hydrogen exerts beneficial effects on cognitive impairment induced by chronic cerebral hypoperfusion. FoxO1-mediated autophagy plays an important role in the neuroprotective effects of hydrogen in a rat model of VD. Furthermore, the present findings highlight that HRW should be further investigated as a new therapeutic strategy for VD treatment in the future.
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http://dx.doi.org/10.1016/j.bbr.2018.05.023DOI Listing
January 2019

Severe congenital neutropenia associated with the ELANE gene in Chinese children: case report.

Pediatr Investig 2018 Mar 11;2(1):59-61. Epub 2018 May 11.

Hematology Oncology Center Beijing Children's Hospital Capital Medical University National Center for Children's Health Beijing China.

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http://dx.doi.org/10.1002/ped4.12027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7331322PMC
March 2018

Methylated genomic loci encoding microRNA as a biomarker panel in tissue and saliva for head and neck squamous cell carcinoma.

Clin Epigenetics 2018 3;10:43. Epub 2018 Apr 3.

1Department of Otolaryngology, University of Colorado Anschutz Medical Campus, 12700 E19th Avenue, Aurora, CO 80045 USA.

Background: To identify aberrant promoter methylation of genomic loci encoding microRNA (mgmiR) in head and neck squamous cell carcinoma (HNSCC) and to evaluate a biomarker panel of mgmiRs to improve the diagnostic accuracy of HNSCC in tissues and saliva.

Methods: Methylation of promoter regions of mgmiR candidates was initially screened using HNSCC and control cell lines and further selected using HNSCC and control tissues by quantitative methylation-specific PCR (qMS-PCR). We then examined a panel of seven mgmiRs for validation in an expanded cohort including 189 HNSCC and 92 non-HNSCC controls. Saliva from 86 pre-treatment HNSCC patients and 108 non-HNSCC controls was also examined using this panel of seven mgmiRs to assess the potentials of clinical utilization.

Results: Among the 315 screened mgmiRs, 12 mgmiRs were significantly increased in HNSCC cell lines compared to control cell lines. Seven out of the 12 mgmiRs, i.e., mgmiR9-1, mgmiR124-1, mgmiR124-2, mgmiR124-3, mgmiR129-2, mgmiR137, and mgmiR148a, were further found to significantly increase in HNSCC tumor tissues compared to control tissues. Using multivariable logistic regression with dichotomized variables, a combination of the seven mgmiRs had sensitivity and specificity of 92.6 and 92.4% in tissues and 76.7 and 86.1% in saliva, respectively. Area under the receiver operating curve for this panel was 0.97 in tissue and 0.93 in saliva. This model was validated by independent bootstrap validation and random forest analysis.

Conclusions: mgmiR biomarkers represent a novel and promising screening tool, and the seven-mgmiR panel is able to robustly detect HNSCC in both patient tissue and saliva.
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http://dx.doi.org/10.1186/s13148-018-0470-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5883341PMC
February 2019

Constitutive Expression of Chimeric Transcription Factors Enables Cellulase Synthesis under Non-Inducing Conditions in Penicillium oxalicum.

Biotechnol J 2017 Nov 18;12(11). Epub 2017 Sep 18.

State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, China.

Industrial production of cellulase by filamentous fungi is largely dependent on cellulose, which serves as a natural inducer of cellulase expression. However, insoluble cellulose is unfavorable to submerged fermentation and thus limits the production level of cellulase. The possibility of cellulase production under non-inducing conditions is explored in Penicillium oxalicum by overexpressing two chimeric transcription factors. The chimeric transcription factors contain the DNA binding domain of cellulase transcriptional activator ClrB linked to the C-terminal sequences of XlnR , a constitutively active mutant of hemicellulase transcriptional activator. The obtained recombinant mutants exhibited dramatically improved basal production of cellulase, which was not observed with the overexpression of intact ClrB. When cultivated in a complex cellulosic medium, one of these mutants, OE-CX -S-1, displayed a 7.3-fold increase in cellulase production (2.8 U mL ) relative to the parent strain. The results demonstrate that the dependence of cellulase synthesis on cellulose could be reduced by the overexpression of artificially designed chimeric transcription factors, and offers a potential strategy to engineer fungal strains for improving cellulase production.
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http://dx.doi.org/10.1002/biot.201700119DOI Listing
November 2017

Combining manipulation of transcription factors and overexpression of the target genes to enhance lignocellulolytic enzyme production in .

Biotechnol Biofuels 2017 20;10:100. Epub 2017 Apr 20.

State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China.

Background: Lignocellulolytic enzymes are the main enzymes to saccharify lignocellulose from renewable plant biomass in the bio-based economy. The production of these enzymes is transcriptionally regulated by multiple transcription factors. We previously engineered for improved cellulase production via manipulation of three genes in the cellulase expression regulatory network. However, the potential of combinational engineering of multiple regulators and their targets at protein abundance and activity levels has not been fully explored.

Results: Here, we verified that a point mutation XlnR in transcription factor XlnR enhanced the expression of lignocellulolytic enzymes, particularly hemicellulases, in . Then, overexpression of XlnR with a constitutive promoter was combined with the overexpression of cellulase transcriptional activator ClrB and deletion of carbon catabolite repressor CreA. The resulted strain RE-7 showed 8.9- and 51.5-fold increased production of cellulase and xylanase relative to the starting strain M12, respectively. Further overexpression of two major cellulase genes - and enabled an additional 13.0% improvement of cellulase production. In addition, XlnR led to decreased production of β-glucosidase and amylase, which could be attributed to the reduced transcription of corresponding enzyme-encoding genes.

Conclusions: The results illustrated that combinational manipulation of the involved transcription factors and their target genes was a viable strategy for efficient production of lignocellulolytic enzymes in filamentous fungi. The striking negative effect of XlnR mutation on amylase production was also highlighted.
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http://dx.doi.org/10.1186/s13068-017-0783-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5397729PMC
April 2017
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