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Pushplata Prasad - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic analyses reveal molecular signatures associated with functional divergence among Subtilisin like Serine Proteases are linked to lifestyle transitions in Hypocreales.
BMC evolutionary biology, 2016Co-Authors: Deepti Varshney, Akanksha Jaiswar, Alok Adholeya, Pushplata PrasadAbstract:Background Subtilisin-like serine proteases or Subtilases in fungi are important for penetration and colonization of host. In Hypocreales, these proteins share several properties with other fungal, bacterial, plant and mammalian homologs. However, adoption of specific roles in entomopathogenesis may be governed by attainment of unique biochemical and structural features during the evolutionary course. Due to such functional shifts Subtilases coded by different family members of Hypocreales acquire distinct features according to respective hosts and lifestyle. We conducted phylogenetic and DIVERGE analyses and identified important protein residues that putatively assign functional specificity to Subtilases in fungal families/species under the order Hypocreales.
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Phylogenetic analyses reveal molecular signatures associated with functional divergence among Subtilisin like Serine Proteases are linked to lifestyle transitions in Hypocreales
BMC Evolutionary Biology, 2016Co-Authors: Deepti Varshney, Akanksha Jaiswar, Alok Adholeya, Pushplata PrasadAbstract:Background Subtilisin-like serine proteases or Subtilases in fungi are important for penetration and colonization of host. In Hypocreales, these proteins share several properties with other fungal, bacterial, plant and mammalian homologs. However, adoption of specific roles in entomopathogenesis may be governed by attainment of unique biochemical and structural features during the evolutionary course. Due to such functional shifts Subtilases coded by different family members of Hypocreales acquire distinct features according to respective hosts and lifestyle. We conducted phylogenetic and DIVERGE analyses and identified important protein residues that putatively assign functional specificity to Subtilases in fungal families/species under the order Hypocreales. Results A total of 161 Subtilases coded by 10 species from five different families under the fungal order Hypocreales was included in the analysis. Based on the presence of conserved domains, the Subtilase genes were divided into three subfamilies, Subtilisin (S08.005), Proteinase K (S08.054) and Serine-carboxyl peptidases (S53.001). These subfamilies were investigated for phylogenetic associations, protein residues under positive selection and functional divergence among paralogous clades. The observations were co-related with the life-styles of the fungal families/species. Phylogenetic and Divergence analyses of Subtilisin (S08.005) and Proteinase K (S08.054) families of proteins revealed that the paralogous clades were clear-cut representation of familial origin of the protein sequences. We observed divergence between the paralogous clades of plant-pathogenic fungi (Nectriaceae), insect-pathogenic fungi (Cordycipitaceae/Clavicipitaceae) and nematophagous fungi (Ophiocordycipitaceae). In addition, Subtilase genes from the nematode-parasitic fungus Purpureocillium lilacinum made a unique cluster which putatively indicated that the fungus might have developed distinctive mechanisms for nematode-pathogenesis. Our evolutionary genetics analysis revealed evidence of positive selection on the Subtilisin (S08.005) and Proteinase K (S08.054) protein sequences of the entomopathogenic and nematophagous species belonging to Cordycipitaceae, Clavicipitaceae and Ophiocordycipitaceae families of Hypocreales. Conclusions Our study provided new insights into the evolution of Subtilisin like serine proteases in Hypocreales, a fungal order largely consisting of biological control species. Subtilisin (S08.005) and Proteinase K (S08.054) proteins seemed to play important roles during life style modifications among different families and species of Hypocreales. Protein residues found significant in functional divergence analysis in the present study may provide support for protein engineering in future.
Peter Döbbeler - One of the best experts on this subject based on the ideXlab platform.
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Bryocentria hypothallina (Hypocreales) – a new species on Metzgeria furcata
2015Co-Authors: Björn Nordén, Alain Gardiennet, Jean-paul Priou, Peter DöbbelerAbstract:Bryocentria hypothallina (Bionectriaceae, Hypocreales) is described as a new species. It grows necrotrophically on the liverwort Metzgeria furcata (Metzgeriales), causing bleached, insular infections. Ascomata are formed on the ventral side of the thalli and perforate them from below. The novel ascomycete species is recorded from France, Norway, and Spain. Thus, the obligately bryophilous genus Bryocentria now includes eight species. Our new species is characterized ecologically by its specialized microhabitat, and morphologically by having ascospores bearing tiny cyanophilous warts
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Gynonectria intraspora gen. et sp. nov. (Hypocreales), a perianthicolous phyllosphere fungus with a novel ascospore type
Mycological Progress, 2012Co-Authors: Peter DöbbelerAbstract:Gynonectria intraspora is described as a new monotypic genus of the Hypocreales (Ascomycetes). Relatively large perithecia form individually within the perianths of the hepatic Odontolejeunea sp. (Lejeuneaceae, Porellales), which grow in the phyllosphere of living vascular plants in the rainforests of Costa Rica and Panama. As in other hyperepiphyllous perianthicolous species, hyphae concentrate in the region of the sporophyte–gametophyte junction. They prevent sporophyte maturation, but do not visibly affect the leafy gametophyte. The most intriguing character of G. intraspora is exhibited by the ascospores. While they are still in the asci, each of them cleaves two new spores within its lumina leaving residual primary spore plasma around them. This novel spore type is comparable to the endoconidia of black meristematic fungi and is called an "intraspore". The formation of intraspores together with other features seem to indicate that the obligate hyperepiphyllous Hypocreales are undergoing an active evolutionary process of diversification, as are their epiphyllous lejeuneaceous hosts.
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Ascospore diversity of bryophilous Hypocreales and two new hepaticolous Nectria species.
Mycologia, 2005Co-Authors: Peter DöbbelerAbstract:Hypocreales represents one of the most successful orders of ascomycetes on mosses and hepatics, and more than 30 obligately bryophilous species belonging to seven genera of Bionectriaceae and Nectriaceae are known. These fungi have a remarkably wide range of ascospore types that differ in form, size and septation. Especially heterogeneous are the ascospores of the six hypocrealean parasites recorded on European populations of Frullania dilatata. Patterns of distribution of bryophilous Hypocreales on this host appear to follow the principles of island biogeography. Two new leaf-perforating species of Nectria with unusual ascospores are described. Nectria foertheri Dobbeler sp. nov. grows biotrophically on Porella sp. in Guatemala, and N. lagodes Dobbeler sp. nov. is a necrotroph on Frullania dilatata in Italy and Greece.
Zhiyong Li - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetically Diverse Cultivable Fungal Community and Polyketide Synthase (PKS), Non-ribosomal Peptide Synthase (NRPS) Genes Associated with the South China Sea Sponges
Microbial Ecology, 2011Co-Authors: Kang Zhou, Fengli Zhang, Xia Zhang, Zhiyong LiAbstract:Compared with sponge-associated bacteria, the phylogenetic diversity of fungi in sponge and the association of sponge fungi remain largely unknown. Meanwhile, no detection of polyketide synthase (PKS) or non-ribosomal peptide synthase (NRPS) genes in sponge-associated fungi has been attempted. In this study, diverse and novel cultivable fungi including 10 genera (Aspergillus, Ascomycete, Fusarium, Isaria, Penicillium, Plectosphaerella, Pseudonectria, Simplicillium, Trichoderma, and Volutella) in four orders (Eurotiales, Hypocreales, Microascales, and Phyllachorales) of phylum Ascomycota were isolated from 10 species marine sponges in the South China Sea. Eurotiales and Hypocreales fungi were suggested as sponge generalists. The predominant isolates were Penicillium and Aspergillus in Eurotiales followed by Volutella in Hypocreales. Based on the conserved Beta-ketosynthase of PKS and A domain of NRPS, 15 polyketide synthases, and four non-ribosomal peptides synthesis genes, including non-reducing and reducing PKSs and hybrid PKS–NRPS, were detected in these fungal isolates. A lateral gene transfer event was indicated in the comparison between the phylogenetic diversity of 18S rRNA genes and β-ketoacyl synthase domain sequences. Some fungi, especially those with PKS or NRPS genes, showed antimicrobial activity against P. fluorescens, S. aureus and B. subtilis. It was the first time to investigate PKS and NRPS genes in sponge-associated fungi. Based on the detected antibiotics biosynthesis-related PKS and NRPS genes and antimicrobial activity, the potential ecological role of sponge-associated fungi in the chemical defense for sponge host was suggested. This study extended our knowledge of sponge-associated fungal phylogenetic diversity and their potential roles in the chemical defense.
Joseph W. Spatafora - One of the best experts on this subject based on the ideXlab platform.
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new 1f1n species combinations in ophiocordycipitaceae Hypocreales
IMA fungus, 2015Co-Authors: Joseph W. Spatafora, Gi-ho Sung, Ryan M. Kepler, Alisha C Quandt, Bhushan Shrestha, Nigel L Hyweljones, Jennifer J LuangsaardAbstract:Based on the taxonomic and nomenclatural recommendations of Quandt et al. (2014) new species combinations are made for Ophiocordycipitaceae. These new combinations are compliant with recent changes in the International Code of Nomenclature for algae, fungi, and plants (ICN) and the abolition of the dual system of nomenclature for fungi. These changes include 10 new combinations into Drechmeria, four new combinations into Harposporium, 23 new combinations and 15 synonymies in Ophiocordyceps, and one new combination into Purpureocillium.
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The genome of the truffle-parasite Tolypocladium ophioglossoides and the evolution of antifungal peptaibiotics
BMC Genomics, 2015Co-Authors: C. Alisha Quandt, Kathryn E. Bushley, Joseph W. SpataforaAbstract:Background Two major mycoparasitic lineages, the family Hypocreaceae and the genus Tolypocladium , exist within the fungal order, Hypocreales. Peptaibiotics are a group of secondary metabolites almost exclusively described from Trichoderma species of Hypocreaceae. Peptaibiotics are produced by nonribosomal peptide synthetases (NRPSs) and have antibiotic and antifungal activities. Tolypocladium species are mainly truffle parasites, but a few species are insect pathogens. Results The draft genome sequence of the truffle parasite Tolypocladium ophioglossoides was generated and numerous secondary metabolite clusters were discovered, many of which have no known putative product. However, three large peptaibiotic gene clusters were identified using phylogenetic analyses. Peptaibiotic genes are absent from the predominantly plant and insect pathogenic lineages of Hypocreales, and are therefore exclusive to the largely mycoparasitic lineages. Using NRPS adenylation domain phylogenies and reconciliation of the domain tree with the organismal phylogeny, it is demonstrated that the distribution of these domains is likely not the product of horizontal gene transfer between mycoparasitic lineages, but represents independent losses in insect pathogenic lineages. Peptaibiotic genes are less conserved between species of Tolypocladium and are the product of complex patterns of lineage sorting and module duplication. In contrast, these genes are more conserved within the genus Trichoderma and consistent with diversification through speciation. Conclusions Peptaibiotic NRPS genes are restricted to mycoparasitic lineages of Hypocreales, based on current sampling. Phylogenomics and comparative genomics can provide insights into the evolution of secondary metabolite genes, their distribution across a broader range of taxa, and their possible function related to host specificity.
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MOLECULAR SYSTEMATICS OF UNITUNICATE PERITHECIAL ASCOMYCETES: THE CLAVICIPITALES-Hypocreales CONNECTION
Mycologia, 1993Co-Authors: Joseph W. Spatafora, Meredith BlackwellAbstract:Cladistic analysis of partial sequences (840 nucleotide positions) from the nuclear encoded small subunit ribosomal DNA was performed to infer the higher taxonomic placement of the Clavicipitales within unitunicate perithecial ascomycetes. Two major classifications exist concerning the placement of this order of ascomycetes; one places it as a sister group to the Hypocreales and the other, as a member of or a near relative to the Xylariales. A strict consensus of 10 equally most parsimonious trees was in agreement with the placement of the Clavicipitales as a monophyletic sister group to the Hypocreales; relationships within the Clavicipitales were not fully resolved in the strict consensus. The taxa sampled from the Hypocreales comprised a paraphyletic lineage in the strict consensus. Characters derived from anamorphs, stromata, centrum anatomy and nutritional modes were reviewed with respect to their level of congruence with the results inferred from the molecular data.
Deepti Varshney - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic analyses reveal molecular signatures associated with functional divergence among Subtilisin like Serine Proteases are linked to lifestyle transitions in Hypocreales.
BMC evolutionary biology, 2016Co-Authors: Deepti Varshney, Akanksha Jaiswar, Alok Adholeya, Pushplata PrasadAbstract:Background Subtilisin-like serine proteases or Subtilases in fungi are important for penetration and colonization of host. In Hypocreales, these proteins share several properties with other fungal, bacterial, plant and mammalian homologs. However, adoption of specific roles in entomopathogenesis may be governed by attainment of unique biochemical and structural features during the evolutionary course. Due to such functional shifts Subtilases coded by different family members of Hypocreales acquire distinct features according to respective hosts and lifestyle. We conducted phylogenetic and DIVERGE analyses and identified important protein residues that putatively assign functional specificity to Subtilases in fungal families/species under the order Hypocreales.
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Phylogenetic analyses reveal molecular signatures associated with functional divergence among Subtilisin like Serine Proteases are linked to lifestyle transitions in Hypocreales
BMC Evolutionary Biology, 2016Co-Authors: Deepti Varshney, Akanksha Jaiswar, Alok Adholeya, Pushplata PrasadAbstract:Background Subtilisin-like serine proteases or Subtilases in fungi are important for penetration and colonization of host. In Hypocreales, these proteins share several properties with other fungal, bacterial, plant and mammalian homologs. However, adoption of specific roles in entomopathogenesis may be governed by attainment of unique biochemical and structural features during the evolutionary course. Due to such functional shifts Subtilases coded by different family members of Hypocreales acquire distinct features according to respective hosts and lifestyle. We conducted phylogenetic and DIVERGE analyses and identified important protein residues that putatively assign functional specificity to Subtilases in fungal families/species under the order Hypocreales. Results A total of 161 Subtilases coded by 10 species from five different families under the fungal order Hypocreales was included in the analysis. Based on the presence of conserved domains, the Subtilase genes were divided into three subfamilies, Subtilisin (S08.005), Proteinase K (S08.054) and Serine-carboxyl peptidases (S53.001). These subfamilies were investigated for phylogenetic associations, protein residues under positive selection and functional divergence among paralogous clades. The observations were co-related with the life-styles of the fungal families/species. Phylogenetic and Divergence analyses of Subtilisin (S08.005) and Proteinase K (S08.054) families of proteins revealed that the paralogous clades were clear-cut representation of familial origin of the protein sequences. We observed divergence between the paralogous clades of plant-pathogenic fungi (Nectriaceae), insect-pathogenic fungi (Cordycipitaceae/Clavicipitaceae) and nematophagous fungi (Ophiocordycipitaceae). In addition, Subtilase genes from the nematode-parasitic fungus Purpureocillium lilacinum made a unique cluster which putatively indicated that the fungus might have developed distinctive mechanisms for nematode-pathogenesis. Our evolutionary genetics analysis revealed evidence of positive selection on the Subtilisin (S08.005) and Proteinase K (S08.054) protein sequences of the entomopathogenic and nematophagous species belonging to Cordycipitaceae, Clavicipitaceae and Ophiocordycipitaceae families of Hypocreales. Conclusions Our study provided new insights into the evolution of Subtilisin like serine proteases in Hypocreales, a fungal order largely consisting of biological control species. Subtilisin (S08.005) and Proteinase K (S08.054) proteins seemed to play important roles during life style modifications among different families and species of Hypocreales. Protein residues found significant in functional divergence analysis in the present study may provide support for protein engineering in future.