Publications by authors named "Chu-Long Zhang"

25 Publications

  • Page 1 of 1

A preliminary DNA barcode selection for the genus (Russulales, Basidiomycota).

Mycology 2019 Jun 23;10(2):61-74. Epub 2018 Aug 23.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.

is a worldwid genus which has a high species diversity . Aiming accurate and rapid species identification, candidate genes (28S), , and , were analysed as potential DNA barcodes. This analysis included 433 sequences from 38 well-circumscribed species of eight subgenera. Two vital standards were analysed for success species identification using DNA barcodes, specifically inter- and intra-specific variations together with the success rates of PCR amplification and sequencing. Although the gap between inter- and intra-specific variations was narrow, met the qualification standards for a target DNA barcode. Overlapping inter- and intra-specific pairwise distances were observed in , and . The success rates of PCR amplification and sequencing in and were lower than those of others. Gene combinations were also investigated for resolution of species recognition. was suggested as the likely target DNA barcode for , owing to the two viatal standards above. Since has the lowest minimum of inter-specific variation, and has the highest overlap between intra- and inter-species variations among the candidate genes, they are disqualified from the selection for DNA barcode of .
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http://dx.doi.org/10.1080/21501203.2018.1500400DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6493256PMC
June 2019

Identification and characterization of new Muscodor endophytes from gramineous plants in Xishuangbanna, China.

Microbiologyopen 2019 04 21;8(4):e00666. Epub 2018 Jun 21.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.

The endophytic fungi Muscodor spp. produce volatile organic compounds (VOCs) which can inhibit and even kill pathogenic fungi, bacteria, and nematodes. Nine endophytic fungal strains, isolated from the shoots of gramineous plants including Arthraxon hispidus, Eleusine indica, Oplismenus undulatifolius, and Oryza granulata, were identified as Muscodor through phylogenetic analysis of the internal transcribed spacer. Through an SPSS K-means cluster analysis, the nine Muscodor strains were divided into four groups based on the antifungal activities of the VOCs produced by these fungi determined by a two-section confrontation test. The first group contains the strains Y-L-54, W-S-41, Y-S-35, W-T-27, and Y-L-56, which showed the strongest activity. The second and third groups contain W-S-35 and Y-L-43, which showed stronger and moderate activity, respectively. The fourth group contains W-S-38 and N-L-7, which were the weakest in inhibiting the tested pathogens. Thirty-five compounds and the relative amounts of VOCs were determined by SPME-GC-MS and comparison with the NIST14 mass spectrometry database and Agilent MassHunter qualitative and quantitative analyses. These 35 compounds were classified into two different categories: (a) the product of fatty acid degradation, and (b) the intermediate and final metabolite of the metabolic pathway with the precursor of mevalonic acid. SPSS clustering analysis showed that the chemical components of VOCs might be correlated with their bioactivity rather than their phylogenetic assignment and some of the identified compounds might be responsible for antifungal activity. In conclusion, new Muscodor endophytes were recorded in tropical gramineous plants and a number of strains showed remarkable bioactive properties. Therefore, they have important potential applications in the fields of plant disease control.
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http://dx.doi.org/10.1002/mbo3.666DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6460276PMC
April 2019

A Novel Derivative of (-)mycousnine Produced by the Endophytic Fungus , Exhibits High and Selective Immunosuppressive Activity on T Cells.

Front Microbiol 2017 5;8:1251. Epub 2017 Jul 5.

Institute of Materia Medica, Zhejiang Academy of Medical SciencesHangzhou, China.

An endophytic fungus, ZJLQ129, was isolated from the leaves of the traditional Chinese medicine Smilax china. From the fermentation broth and mycelium, a dibenzofurane compound (-)mycousnine (1) was isolated. Chemical modification of it to the amide derivative (-)mycousnine enamine (2), which is new to science, was found to have high and selective immunosuppressive activity: similar to cyclosporin A, (-)mycousnine enamine (2) selectively inhibited T cell proliferation, suppressed the expression of the surface activation antigens CD25 and CD69 and the formation and expression of the cytokines interleukin-2 as well as interferon γ in activated T cells, but did not show any effect on the proliferation of B cells and cancer cells (PANC-1 and A549) and the activation of macrophages. Furthermore, the cytotoxicity of (-)mycousnine enamine was lower than that of cyclosporin A, and its therapeutic index (TC50/EC50) was 4,463.5, which is five-fold higher than that of cyclosporin A. We conclude that (-)mycousnine enamine (2), the semi-synthestic product prepared from the native product (-)mycousnine (1) of the endophyte M. nawae is a novel effective immunosuppressant showing low toxicity and high selectivity.
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http://dx.doi.org/10.3389/fmicb.2017.01251DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5496962PMC
July 2017

An autophagy gene, HoATG5, is involved in sporulation, cell wall integrity and infection of wounded barley leaves.

Microbiol Res 2016 Nov 12;192:326-335. Epub 2016 Aug 12.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China. Electronic address:

The endophytic fungus Harpophora oryzae is a beneficial endosymbiont isolated from wild rice. H. oryzae can not only promote rice growth and biomass accumulation but also protect rice roots from invasion by its close relative Magnaporthe oryzae. Autophagy is a highly evolutionary conserved process from lower to higher eukaryotic organisms, and is involved in the maintenance of normal cell differentiation and development. In this study, we isolated a gene (HoATG5) which encodes an essential protein required for autophagy from the beneficial endophyte fungus H. oryzae. Using targeted gene replacement, a ΔHoATG5 mutant was generated and used to investigate the biological functions of autophagy in H. oryzae. We found that the autophagic process was blocked in the HoATG5 deletion mutant. The mutant showed increased vegetative growth and sporulation, and was sensitive to nutrient starvation. The ΔHoATG5 mutant lost its ability to penetrate and infect the wounded barley leaves. These results provide new knowledge to elaborate the molecular machinery of autophagy in endophytic fungi.
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http://dx.doi.org/10.1016/j.micres.2016.08.008DOI Listing
November 2016

Trichoderma Biodiversity of Agricultural Fields in East China Reveals a Gradient Distribution of Species.

PLoS One 2016 2;11(8):e0160613. Epub 2016 Aug 2.

State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.

We surveyed the Trichoderma (Hypocreales, Ascomycota) biodiversity in agricultural fields in four major agricultural provinces of East China. Trichoderma strains were identified based on molecular approaches and morphological characteristics. In three sampled seasons (spring, summer and autumn), 2078 strains were isolated and identified to 17 known species: T. harzianum (429 isolates), T. asperellum (425), T. hamatum (397), T. virens (340), T. koningiopsis (248), T. brevicompactum (73), T. atroviride (73), T. fertile (26), T. longibrachiatum (22), T. pleuroticola (16), T. erinaceum (16), T. oblongisporum (2), T. polysporum (2), T. spirale (2), T. capillare (2), T. velutinum (2), and T. saturnisporum (1). T. harzianum, T. asperellum, T. hamatum, and T. virens were identified as the dominant species with dominance (Y) values of 0.057, 0.052, 0.048, and 0.039, respectively. The species amount, isolate numbers and the dominant species of Trichoderma varied between provinces. Zhejiang Province has shown the highest diversity, which was reflected in the highest species amount (14) and the highest Shannon-Wiener diversity index of Trichoderma haplotypes (1.46). We observed that relative frequencies of T. hamatum and T. koningiopsis under rice soil were higher than those under wheat and maize soil, indicating the preference of Trichoderma to different crops. Remarkable seasonal variation was shown, with summer exhibiting the highest biodiversity of the studied seasons. These results show that Trichoderma biodiversity in agricultural fields varies by region, crop, and season. Zhejiang Province (the southernmost province in the investigated area) had more T. hamatum than Shandong Province (the northernmost province), not only in isolate amounts but also in haplotype amounts. Furthermore, at haplotype level, only T. hamatum showed a gradient distribution from south to north in correspondence analysis among the four dominant species. The above results would contribute to the application of Trichoderma biocontrol strains.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0160613PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4970770PMC
July 2017

Agrobacterium tumefaciens-mediated transformation: An efficient tool for insertional mutagenesis and targeted gene disruption in Harpophora oryzae.

Microbiol Res 2016 Jan 9;182:40-8. Epub 2015 Oct 9.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China; China Tobacco Gene Research Center, Zhengzhou Tobacco Institute of CNTC, Zhengzhou, China. Electronic address:

The endophytic filamentous fungus Harpophora oryzae is a beneficial endosymbiont isolated from the wild rice. H. oryzae could not only effectively improve growth rate and biomass yield of rice crops, but also induce systemic resistance against the rice blast fungus, Magnaporthe oryzae. In this study, Agrobacterium tumefaciens-mediated transformation (ATMT) was employed and optimized to modify the H. oryzae genes by either random DNA fragment integration or targeted gene replacement. Our results showed that co-cultivation of H. oryzae conidia with A. tumefaciens in the presence of acetosyringone for 48 h at 22 °C could lead to a relatively highest frequency of transformation, and 200 μM acetosyringone (AS) pre-cultivation of A. tumefaciens is also suggested. ATMT-mediated knockout mutagenesis was accomplished with the gene-deletion cassettes using a yeast homologous recombination method with a yeast-Escherichia-Agrobacterium shuttle vector pKOHo. Using the ATMT-mediated knockout mutagenesis, we successfully deleted three genes of H. oryzae (HoATG5, HoATG7, and HoATG8), and then got the null mutants ΔHoatg5, ΔHoatg7, and ΔHoatg8. These results suggest that ATMT is an efficient tool for gene modification including randomly insertional mutagenesis and gene deletion mutagenesis in H. oryzae.
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http://dx.doi.org/10.1016/j.micres.2015.09.008DOI Listing
January 2016

Friend or foe: differential responses of rice to invasion by mutualistic or pathogenic fungi revealed by RNAseq and metabolite profiling.

Sci Rep 2015 Sep 8;5:13624. Epub 2015 Sep 8.

State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.

The rice endophyte Harpophora oryzae shares a common pathogenic ancestor with the rice blast fungus Magnaporthe oryzae. Direct comparison of the interactions between a single plant species and two closely-related (1) pathogenic and (2) mutualistic fungi species can improve our understanding of the evolution of the interactions between plants and fungi that lead to either mutualistic or pathogenic interactions. Differences in the metabolome and transcriptome of rice in response to challenge by H. or M. oryzae were investigated with GC-MS, RNA-seq, and qRT-PCR. Levels of metabolites of the shikimate and lignin biosynthesis pathways increased continuously in the M. oryzae-challenged rice roots (Mo-roots); these pathways were initially induced, but then suppressed, in the H. oryzae-challenged rice roots (Ho-roots). Compared to control samples, concentrations of sucrose and maltose were reduced in the Ho-roots and Mo-roots. The expression of most genes encoding enzymes involved in glycolysis and the TCA cycle were suppressed in the Ho-roots, but enhanced in the Mo-roots. The suppressed glycolysis in Ho-roots would result in the accumulation of glucose and fructose which was not detected in the Mo-roots. A novel co-evolution pattern of fungi-host interaction is proposed which highlights the importance of plant host in the evolution of fungal symbioses.
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http://dx.doi.org/10.1038/srep13624DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4642567PMC
September 2015

The rice endophyte Harpophora oryzae genome reveals evolution from a pathogen to a mutualistic endophyte.

Sci Rep 2014 Jul 22;4:5783. Epub 2014 Jul 22.

State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.

The fungus Harpophora oryzae is a close relative of the pathogen Magnaporthe oryzae and a beneficial endosymbiont of wild rice. Here, we show that H. oryzae evolved from a pathogenic ancestor. The overall genomic structures of H. and M. oryzae were found to be similar. However, during interactions with rice, the expression of 11.7% of all genes showed opposing trends in the two fungi, suggesting differences in gene regulation. Moreover, infection patterns, triggering of host defense responses, signal transduction and nutritional preferences exhibited remarkable differentiation between the two fungi. In addition, the H. oryzae genome was found to contain thousands of loci of transposon-like elements, which led to the disruption of 929 genes. Our results indicate that the gain or loss of orphan genes, DNA duplications, gene family expansions and the frequent translocation of transposon-like elements have been important factors in the evolution of this endosymbiont from a pathogenic ancestor.
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http://dx.doi.org/10.1038/srep05783DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4105740PMC
July 2014

Evidence for biotrophic lifestyle and biocontrol potential of dark septate endophyte Harpophora oryzae to rice blast disease.

PLoS One 2013 18;8(4):e61332. Epub 2013 Apr 18.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.

The mutualism pattern of the dark septate endophyte (DSE) Harpophora oryzae in rice roots and its biocontrol potential in rice blast disease caused by Magnaporthe oryzae were investigated. Fluorescent protein-expressing H. oryzae was used to monitor the colonization pattern. Hyphae invaded from the epidermis to the inner cortex, but not into the root stele. Fungal colonization increased with root tissue maturation, showing no colonization in the meristematic zone, slight colonization in the elongation zone, and heavy colonization in the differentiation zone. H. oryzae adopted a biotrophic lifestyle in roots accompanied by programmed cell death. Real-time PCR facilitated the accurate quantification of fungal growth and the respective plant response. The biocontrol potential of H. oryzae was visualized by inoculation with eGFP-tagged M. oryzae in rice. H. oryzae protected rice from M. oryzae root invasion by the accumulation of H2O2 and elevated antioxidative capacity. H. oryzae also induced systemic resistance against rice blast. This systemic resistance was mediated by the OsWRKY45-dependent salicylic acid (SA) signaling pathway, as indicated by the strongly upregulated expression of OsWRKY45. The colonization pattern of H. oryzae was consistent with the typical characteristics of DSEs. H. oryzae enhanced local resistance by reactive oxygen species (ROS) and high antioxidative level and induced OsWRKY45-dependent SA-mediated systemic resistance against rice blast.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0061332PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3630206PMC
December 2013

Current perspectives on the volatile-producing fungal endophytes.

Crit Rev Biotechnol 2012 Dec 30;32(4):363-73. Epub 2012 Mar 30.

Institute of Subtropical Forestry, Chinese Academy of Forestry, Fuyang, Zhejiang Province, 311400, China.

Microbial-derived volatiles are ubiquitous in the environment and actively engaged in bio-communication with other organisms. Recently, some volatile-producing endophytes (VPEs), cryptic fungal symbionts persisting in healthy plant tissues, have attracted great attention due to their strong antibiotic activity or production of carbon chains that are identical to many of those found in petroleum, while other fragrant volatiles can be used in the flavoring industries. From an application-oriented and biotechnological point of view, these findings show significant promise for sustainable development of agriculture, forestry, and industry, especially in the control of fruit postharvest diseases, soil-borne pathogen management, and bio-fuel production. In comparison, the ecological importance of VPEs has only rarely been addressed and warrants further exploration. In this review, we summarize the current knowledge and future directions in this fascinating research field, and also highlight the constraints and progresses towards commercialization of VPEs products.
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http://dx.doi.org/10.3109/07388551.2011.651429DOI Listing
December 2012

[Effect of ischemia on the structure of bladder in rabbits with partial bladder outlet obstruction].

Zhonghua Yi Xue Za Zhi 2011 Nov;91(42):3007-11

Graduate School of South Medical University, Guangzhou 510515, China.

Objective: To compare the structures and functions of rabbit bladder after partial bladder outlet obstruction versus without ischemia so as to explore the effects of ischemia on bladder pathogenesis in rabbits with partial bladder outlet obstruction.

Methods: A total of 64 mature male rabbits were divided into 4 groups (n = 16 each). Four of each group underwent operation to establish an ischemic animal model (ischemia group), another 4 underwent operation to establish a partial bladder outlet obstruction animal model (obstruct group), the other 4 underwent operation to establish an ischemic and partial bladder outlet obstruction animal model (combination group) and the remaining 4 underwent a sham operation as control. The rabbits in 4 groups were evaluated at Week 1, 2, 4 and 8 post-operation respectively. The weight of bladder, the thickness of mucosal, submucosa, muscular layer and placenta percreta and the activities of sarco/endoplasmic reticulum Ca(2+) ATPase citrate synthase of cystic smooth muscle were detected respectively. MASSON staining was used to observe the smooth muscle and collagen in stroma of bladder and S-100 staining for observing the neurons in bladder.

Results: In obstruct and combination groups, the weights of bladder at week 1 were (5.10 ± 0.29) g and (4.80 ± 0.37) g respectively. They were both significantly higher than control group [(1.93 ± 0.17) g, all P < 0.05]. The weights of bladder in obstruct and combination groups peaked at Week 4 and they were (18.48 ± 2.03) g and (12.35 ± 0.39) g respectively. The weight of bladder in obstruct group was significantly heavier than combination group in the same terms. And they were both significantly heavier than control and ischemia groups (all P < 0.05). Muscular tissue vicariously thickened during the first 4 weeks, and collagen and stroma increased at Week 4 in obstruct group. Muscular tissue, collagen and stroma all increased initially. But at Week 2 only collagen and stroma increased in combination group. Compare with control group, the other groups all have deletion of neurons, especially in combination group. The activities of sarco/endoplasmic reticulum Ca(2+) ATPase and citrate synthase of cystic smooth muscle of obstruct group peaked at Week 4. In combination group, the activities of sarco/endoplasmic reticulum Ca(2+) ATPase and citrate synthase of cystic smooth muscle were decreased over 2 - 8 weeks. In the same terms, the activities of sarco/endoplasmic reticulum Ca(2+) ATPase and citrate synthase of cystic smooth muscle in control group were significantly higher than those in obstruct and combination groups (all P < 0.05).

Conclusion: Ischemia can reduce the tolerance of bladder and aggravate the impairment of bladder to partial outlet obstruction.
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November 2011

Bioactive metabolites from Phoma species, an endophytic fungus from the Chinese medicinal plant Arisaema erubescens.

Appl Microbiol Biotechnol 2012 Feb 4;93(3):1231-9. Epub 2011 Aug 4.

Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.

Through bioassay-guided fractionation, the EtOAc extract of a culture broth of the endophytic fungus Phoma species ZJWCF006 in Arisaema erubescens afforded a new α-tetralone derivative, (3S)-3,6,7-trihydroxy-α-tetralone (1), together with cercosporamide (2), β-sitosterol (3), and trichodermin (4). The structures of compounds were established on the basis of spectroscopic analyses. Compounds 1, 2, and 3 were obtained from Phoma species for the first time. Additionally, the compounds were subjected to bioactivity assays, including antimicrobial activity, against four plant pathogenic fungi (Fusarium oxysporium, Rhizoctonia solani, Colletotrichum gloeosporioides, and Magnaporthe oryzae) and two plant pathogenic bacteria (Xanthomonas campestris and Xanthomonas oryzae), as well as in vitro antitumor activities against HT-29, SMMC-772, MCF-7, HL-60, MGC80-3, and P388 cell lines. Compound 1 showed growth inhibition against F. oxysporium and R. solani with EC₅₀ values of 413.22 and 48.5 μg/mL, respectively. Additionally, compound 1 showed no cytotoxicity, whereas compound 2 exhibited cytotoxic activity against the six tumor cell lines tested, with IC₅₀ values of 9.3 ± 2.8, 27.87 ± 1.78, 48.79 ± 2.56, 37.57 ± 1.65, 27.83 ± 0.48, and 30.37 ± 0.28 μM, respectively. We conclude that endophytic Phoma are promising sources of natural bioactive and novel metabolites.
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http://dx.doi.org/10.1007/s00253-011-3472-3DOI Listing
February 2012

An autophagy gene, TrATG5, affects conidiospore differentiation in Trichoderma reesei.

Res Microbiol 2011 Oct 22;162(8):756-63. Epub 2011 Jun 22.

State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou 310058, China.

Autophagy is a highly conserved process in lower to higher eukaryotic organisms, and occurs in many types of cells as tissues are remodeled during development. In this study, we investigated the functional role of the Trichoderma reesei TrATG5 gene, which encodes an essential protein required for autophagy. TrATG5 is conserved in structure and function in the filamentous fungi and might clearly rescue the pathogenicity function of MgATG5 in Magnaporthe oryzae. Target gene disruption was used to study the functions of TrATG5. It was found that the autophagic process was blocked in the TrATG5 deletion mutant. The mutant was sensitive to nutrient starvation, with abnormal conidiophores and reduced production of conidia. This new evidence might help to elucidate the molecular machinery of autophagy in filamentous fungi.
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http://dx.doi.org/10.1016/j.resmic.2011.06.011DOI Listing
October 2011

Distinctive endophytic fungal assemblage in stems of wild rice (Oryza granulata) in China with special reference to two species of Muscodor (Xylariaceae).

J Microbiol 2011 Feb 3;49(1):15-23. Epub 2011 Mar 3.

Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Biotechnology, Zhejiang University, Hangzhou, 310029, PR China.

Ecological niches in the rhizosphere and phyllosphere of grasses capable of sustaining endophytes have been extensively studied. In contrast, little information regarding the identity and functions of endophytic fungi in stems is available. In this study, we investigated the taxonomic affinities, diversity, and host specificities of culturable endophytes in stems of wild rice (Oryza granulata) in China. Seventy-four isolates were recovered. Low recovery rate (11.7%) indicated that there were relatively few sites for fungal infection. Identification using morphology, morphospecies sorting, and molecular techniques resulted in classification into 50 taxa, 36 of which were recovered only once. Nucleotide sequence similarity analysis indicated that 30% of the total taxa recovered were highly divergent from known species and thus may represent lineages new to science. Most of the taxa were classified as members of the classes Sordariomycetes or Dothideomycetes (mainly in Pleosporales). The presence of Arthrinium and Magnaporthaceae species, most often associated with poaceous plants, suggested a degree of host specificity. A polyphasic approach was employed to identify two Muscodor taxa based on (i) ITS and RPB2 phylogenies, (ii) volatile compounds produced, and (iii) an in vitro bioassay of antifungal activity. This to our knowledge is only the second report regarding the isolation of Muscodor spp. in China. Therefore, we hypothesize that wild plants represent a huge reservoir of unknown fungi. The prevalence, novelty, and species-specificity of unique isolates necessitate a reevaluation of their contribution to ecosystem function and fungal biodiversity.
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http://dx.doi.org/10.1007/s12275-011-0213-3DOI Listing
February 2011

From pattern to process: species and functional diversity in fungal endophytes of Abies beshanzuensis.

Fungal Biol 2011 Mar 30;115(3):197-213. Epub 2010 Nov 30.

Institute of Subtropical Forestry, Chinese Academy of Forestry, Fuyang, China.

The biodiversity-functional relationship in fungal ecology was recently developed and debated, but has rarely been addressed in endophytes. In this study, an integrative culture system was designed to capture a rich fungal consortium from the conifer Abies beshanzuensis. Results indicate an impressive diversity of fungal lineages (a total of 84 taxa classified in Dikarya) and a relatively high proportion of hitherto unknown species (27.4%). The laccase gene was used as a functional marker due to its involvement in lignocellulose degradation. Remarkable diversity of laccase genes was found across a wide range of taxa, with at least 35 and 19 distinct sequences in ascomycetes and basidiomycetes respectively, were revealed. Many groups displayed variable ability to decompose needles. Furthermore, many ascomycetes, including three volatile-producing Muscodor species (Xylariaceae), showed the ability to inhibit pathogens. Notably, most laccase-producing species showed little or no antibiosis and vice versa. Clavicipitalean and ustilaginomycetous fungi, specifically toxic to insects, were inferred from taxonomic information. Intra-specific physiological variation in Pezicula sporulosa, a second dominant species, was clearly high. We conclude that a suite of defensive characteristics in endophytes contributes to improving host fitness under various stresses and that a diversity of laccase genes confers an ecological advantage in competition for nutrients. Intra-specific diversity may be of great ecological significance for ecotypic adaptation. These findings suggest a fair degree of functional complementarity rather than redundancy among endemic symbionts of natural plant populations.
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http://dx.doi.org/10.1016/j.funbio.2010.11.002DOI Listing
March 2011

Muscodor fengyangensis sp. nov. from southeast China: morphology, physiology and production of volatile compounds.

Fungal Biol 2010 Oct 29;114(10):797-808. Epub 2010 Jul 29.

Institute of Biotechnology, Zhejiang University, Hangzhou, China.

The fungal genus Muscodor was erected on the basis of Muscodor albus, an endophytic fungus originally isolated from Cinnamomum zeylanicum. It produces a mixture of volatile organic compounds (VOCs) with antimicrobial activity that can be used as mycofumigants. The genus currently comprises five species. Here we describe the isolation and characterization of a new species of Muscodor on the basis of five endophytic fungal strains from leaves of Actinidia chinensis, Pseudotaxus chienii and an unidentified broad leaf tree in the Fengyangshan Nature Reserve, Zhejiang Province, Southeast of China. They exhibit white colonies on potato dextrose agar (PDA) media, rope-like mycelial strands, but did not sporulate. The optimum growth temperature is 25°C. The results of a phylogenetic analysis based on four loci (ITS1-5.8S-ITS2, 28S rRNA, rpb2 and tub1) are consistent with the hypothesis that these five strains belong to a single taxon. All five strains also produce volatile chemical components with antimicrobial activity in vitro, which were different from those previously described for other Muscodor species.
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http://dx.doi.org/10.1016/j.funbio.2010.07.006DOI Listing
October 2010

A new species of Harpophora (Magnaporthaceae) recovered from healthy wild rice (Oryza granulata) roots, representing a novel member of a beneficial dark septate endophyte.

FEMS Microbiol Lett 2010 Jun 20;307(1):94-101. Epub 2010 Mar 20.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China.

A survey of the endophytic fungal community of wild rice (Oryza granulata) in China was conducted. Two isolates recovered from healthy roots are assumed to be dark septate endophytes (DSEs). They are morphologically similar to species from the genus Harpophora and are identified as a new species, Harpophora oryzae, based on the molecular phylogeny and morphological characteristics. A neighbor-joining tree constructed from ITS-5.8S rRNA gene regions reveals that H. oryzae forms a distinctive subclade within the genus Harpophora, and is not genetically close to other species of Harpophora. Harpophora oryzae exhibits a moderate growth rate, with a frequent production of rope-like strands. It sporulates readily on artificial medium. Phialides are usually flask or bottle shaped and occur singly along hyphae or laterally and terminally on branched, hyaline to brown conidiophores, and also form whorls on metulae. Conidiophores are mostly branched with a slightly thickened wall, varying in dimensions. Conidia are one-celled and hyaline, most of them being falcate and strongly curved. The morphological differences between Harpophora spp. and Harpophora-like anamorphs representing different orders are also discussed. An in vitro inoculation test showed that H. oryzae may contribute towards improving rice (Oryza sativa L.) growth. Microscopic inspection of roots and phylogenetic placement of isolates further confirmed that H. oryzae represents a novel member of DSEs.
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http://dx.doi.org/10.1111/j.1574-6968.2010.01963.xDOI Listing
June 2010

[Effectiveness and significance of prostatic ischemia in rabbit].

Zhonghua Yi Xue Za Zhi 2009 Dec;89(45):3224-7

Department of Urology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou 510010, China.

Objective: To evaluate the effect of prostatic ischemia in rabbit and approach the significance of ischemia in the development of benign prostatic hyperplasia.

Methods: Male rabbits underwent surgical prostatic ischemia for durations of 1, 2, 4, 8 and 12 weeks and sham-operated rabbits served as controls. The weight of prostate was examined and a histological examination conducted. Ki67 immunohistochemical stain for the generation of prostatic cells and TUNEL test for the apoptosis of prostatic cells were used.

Results: In sham-operated rabbits, the mean (SD) weight of prostate were 0.831(0.127) g, the mean (SD) positive Ki67 staining prostatic epithelial cells 2.1(0.8) in 100 prostatic epithelial cells and stromal cells 2.6(1.1) in 100, mean (SD) positive TUNEL test prostatic epithelial cells 2.0(1.0) in 100 and stromal cells 2.5(0.7) in 100. In operated rabbits, the generation of prostatic stromal cells increased and the apoptosis of prostatic stromal cells decreased over 1 - 12 weeks. The generation of prostatic epithelial cells increased and the apoptosis of prostatic epithelial cells decreased over 2 - 12 weeks, but in the first week, there were no significantly difference between operated and sham-operated rabbits in the generation and apoptosis of prostatic epithelial cells. The weight of prostate in operated animals increased at Weeks 4, 8 and 12, were significantly heavier than sham-operated rabbits, 1 week post-op and 2 weeks post-op rabbits, there were no significantly difference between the latter 3 groups.

Conclusion: Ischemia can induce the gain of prostatic weight by improving the generation and inhibiting the apoptosis of prostatic cells. And the effect of ischemia to prostate is correlated with ischemic time. Ischemia may play an important role in the development of benign prostatic hyperplasia. The first response to ischemia is the change of prostatic stromal cells.
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December 2009

Identity, diversity, and molecular phylogeny of the endophytic mycobiota in the roots of rare wild rice (Oryza granulate) from a nature reserve in Yunnan, China.

Appl Environ Microbiol 2010 Mar 28;76(5):1642-52. Epub 2009 Dec 28.

State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China.

Rice (Oryza sativa L.) is, on a global scale, one of the most important food crops. Although endophytic fungi and bacteria associated with rice have been investigated, little is known about the endophytic fungi of wild rice (Oryza granulate) in China. Here we studied the root endophytic mycobiota residing in roots of O. granulate by the use of an integrated approach consisting of microscopy, cultivation, ecological indices, and direct PCR. Microscopy confirmed the ubiquitousness of dark septate endophytes (DSEs) and sclerotium-like structures in root tissues. Isolations from 204 root segments from 15 wild rice plants yielded 58 isolates, for which 31 internal transcribed spacer (ITS)-based genotypes were recorded. The best BLAST match indicated that 34.5% of all taxa encountered may represent hitherto undescribed species. Most of the fungi were isolated with a very low frequency. Calculation of ecological indices and estimation of taxon accumulation curves indicated a high diversity of fungal species. A culture-independent approach was also performed to analyze the endophytic fungal community. Three individual clone libraries were constructed. Using a threshold of 90% similarity, 35 potentially different sequences (phylotypes) were found among 186 positive clones. Phylogenetic analysis showed that frequently detected clones were classified as Basidiomycota, and 60.2% of total analyzed clones were affiliated with unknown taxa. Exophiala, Cladophialophora, Harpophora, Periconia macrospinosa, and the Ceratobasidium/Rhizoctonia complex may act as potential DSE groups. A comparison of the fungal communities characterized by the two approaches demonstrated distinctive fungal groups, and only a few taxa overlapped. Our findings indicate a complex and rich endophytic fungal consortium in wild rice roots, thus offering a potential bioresource for establishing a novel model of plant-fungal mutualistic interactions.
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http://dx.doi.org/10.1128/AEM.01911-09DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2832373PMC
March 2010

White-spot disease of Chinese soft-shelled turtles (Trionyx sinens) caused by Paecilomyces lilacinus.

J Zhejiang Univ Sci B 2008 Jul;9(7):578-81

Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, China.

Chinese soft-shelled turtles (Trionyx sinens) in culture farms using an artificial warming system in Zhejiang, China, often show typical signs of white-spot disease such as white spots on their bodies, skin lesions, anorexia and eventually death. The sick turtles were mostly 5~80 g in weight. A suspected fungal pathogen was isolated from the sick turtles and verified as Paecilomyces lilacinus by sequence analysis of the internal transcribed spacer (ITS) of its ribosomal DNA (rDNA). Detailed morphological examinations were also conducted to confirm the white-spot disease.
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http://dx.doi.org/10.1631/jzus.B0720009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2443355PMC
July 2008

Clavatol and patulin formation as the antagonistic principle of Aspergillus clavatonanicus, an endophytic fungus of Taxus mairei.

Appl Microbiol Biotechnol 2008 Apr 4;78(5):833-40. Epub 2008 Mar 4.

Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China.

Many endophytic fungi are known to protect plants from plant pathogens, but the antagonistic mechanism has rarely been revealed. In this study, we wished to learn whether an endophytic Aspergillus sp., isolated from Taxus mairei, would indeed produce bioactive components, and if so whether (a) they would antagonize plant pathogenic fungi; and (b) whether this Aspergillus sp. would produce the compound also under conditions of confrontation with these fungi. The endophytic fungal strain from T. mairei was identified as Aspergillus clavatonanicus by analysis of morphological characteristics and the sequence of the internal transcribed spacers (ITS rDNA) of rDNA. When grown in surface culture, the fungus produced clavatol (2',4'-dihydroxy-3',5'-dimethylacetophenone) and patulin (2-hydroxy-3,7-dioxabicyclo [4.3.0]nona-5,9-dien-8-one), as shown by shown by NMR, MS, X-ray, and EI-MS analysis. Both exhibited inhibitory activity in vitro against several plant pathogenic fungi, i.e., Botrytis cinerea, Didymella bryoniae, Fusarium oxysporum f. sp. cucumerinum, Rhizoctonia solani, and Pythium ultimum. During confrontation with P. ultimum, A. clavatonanicus antagonized its growth of P. ultimum, and both clavatol as well as patulin were formed as the only bioactive components, albeit with different kinetics. We conclude that A. clavatonanicus produces clavatol and patulin, and that these two polyketides may be involved in the protection of T. mairei against attack by plant pathogens by this Aspergillus sp.
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http://dx.doi.org/10.1007/s00253-008-1371-zDOI Listing
April 2008

Bostrycin.

Acta Crystallogr Sect E Struct Rep Online 2008 Oct 31;64(Pt 11):o2226. Epub 2008 Oct 31.

The title compound, C(16)H(16)O(8), is a potent nonspecific phyto-toxin. The crystal structure is the average of two tauto-mers, 5,6,7,9,10-penta-hydr-oxy-2-meth-oxy-7-methyl-1,4,5,6,7,8-hexa-hydro-anthracene-1,4-dione and 1,4,5,6,7-pentahydr-oxy-2-meth--oxy-7-methyl-5,6,7,8,9,10-hexa-hydro-anthracene-9,10-di-one. The cyclo-hexene rings in both tautomers display a half-chair conformation. An extensive O-H⋯O hydrogen-bonding network is present in the crystal structure.
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http://dx.doi.org/10.1107/S1600536808032030DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2959567PMC
October 2008

Trichodermin (4β-acet-oxy-12,13-epoxy-trichothec-9-ene).

Acta Crystallogr Sect E Struct Rep Online 2008 Mar 12;64(Pt 4):o702. Epub 2008 Mar 12.

In the title natural product, C(17)H(24)O(4), which is a very potent inhibitor of protein synthesis in mammalian cells, the five-membered ring displays an envelope conformation, whereas the two six-membered rings show different conformations, viz. chair and half-chair.
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http://dx.doi.org/10.1107/S1600536808006168DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2960951PMC
March 2008

Trichoderma taxi sp. nov., an endophytic fungus from Chinese yew Taxus mairei.

FEMS Microbiol Lett 2007 May 16;270(1):90-6. Epub 2007 Feb 16.

Institute of Biotechnology, Zhejiang University, Hangzhou, China.

Trichoderma taxi sp. nov. was isolated as an endophytic fungus of Taxus mairei growing at the Guanshan Nature Reserve of Jiangxi province, China, and characterized by a combination of phenotypic characteristics and gene analyses of ITS1 and 2, tef1 and rpb2 gene sequences. Distinctive morphological characters of Trichoderma taxi are its white small subglobose conidia and pachybasium-like conidiophores aggregated into compact pustules. Phylogenetically, Trichoderma taxi forms an independent branch in vicinity to the Lutea (Hypocrea lutea, Hypocrea melanomagna) and Pachybasioides (Hypocrea pachybasioides, Hypocrea minutispora, Hypocrea pilulifera, Hypocrea parapilulifera, Hypocrea lacuwombatensis and Hypocrea stellata) clades.
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http://dx.doi.org/10.1111/j.1574-6968.2007.00659.xDOI Listing
May 2007

Trichoderma biodiversity in China: evidence for a North to South distribution of species in East Asia.

FEMS Microbiol Lett 2005 Oct;251(2):251-7

Institute of Biotechnology, Zhejiang University, 310029 China.

Towards assessing the biodiversity and biogeography of Trichoderma, we have analyzed the occurrence of Trichoderma species in soil and litter from four areas in China: North (Hebei province), South-East (Zhejiang province), West (Himalayan, Tibet) and South-West (Yunnan province). One hundred and thirty five isolates were grouped according to tentative morphological identification. A representative 64 isolates were verified at the species level by the oligonucleotide barcode program TrichO Key v.1.0 and the custom BLAST server TrichoBLAST, using sequences of the ITS1 and 2 region of the rRNA cluster and from the longest intron of the tef1 (translation elongation factor 1-alpha) gene. Eleven known species (Trichoderma asperellum, T. koningii, T. atroviride, T. viride, T. velutinum, T. cerinum, T. virens, T. harzianum, T. sinensis, T. citrinoviride, T. longibrachiatum) and two putative new species (T. sp. C1, and T. sp. C2), distinguished from known species both by morphological characters and phylogenetic analysis, were identified. A significant difference in the occurrence of these species was found between the North (Hebei) and South-West (Yunnan) areas, which correlates with previously reported species distributions in Siberia and South-East Asia, respectively. As in previous studies, T. harzianum accounted for almost half of the biodiversity; although, in this study, it was exclusively found in the North, and was predominantly represented by an ITS1 and 2 haplotype, which has so far been rarely found elsewhere. This study therefore reveals a North-South gradient in species distribution in East Asia, and identifies Northern China as a potential center of origin of a unique haplotype of T. harzianum.
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http://dx.doi.org/10.1016/j.femsle.2005.08.034DOI Listing
October 2005