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Quan ND, Nguyen NL, Giang TTH, Ngan NTT, Hien NT, Tung NV, Trang NHT, Lien NTK, Nguyen HH. Genome Characteristics of the Endophytic Fungus Talaromyces sp. DC2 Isolated from Catharanthus roseus (L.) G. Don. J Fungi (Basel) 2024; 10:352. [PMID: 38786707 PMCID: PMC11122143 DOI: 10.3390/jof10050352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/06/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024] Open
Abstract
Talaromyces sp. DC2 is an endophytic fungus that was isolated from the stem of Catharanthus roseus (L.) G. Don in Hanoi, Vietnam and is capable of producing vinca alkaloids. This study utilizes the PacBio Sequel technology to completely sequence the whole genome of Talaromyces sp. DC2The genome study revealed that DC2 contains a total of 34.58 Mb spanned by 156 contigs, with a GC content of 46.5%. The identification and prediction of functional protein-coding genes, tRNA, and rRNA were comprehensively predicted and highly annotated using various BLAST databases, including non-redundant (Nr) protein sequence, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Clusters of Orthologous Groups (COG), and Carbohydrate-Active Enzymes (CAZy) databases. The genome of DC2 has a total of 149, 227, 65, 153, 53, and 6 genes responsible for cellulose, hemicellulose, lignin, pectin, chitin, starch, and inulin degradation, respectively. The Antibiotics and Secondary Metabolites Analysis Shell (AntiSMASH) analyses revealed that strain DC2 possesses 20 biosynthetic gene clusters responsible for producing secondary metabolites. The strain DC2 has also been found to harbor the DDC gene encoding aromatic L-amino acid decarboxylase enzyme. Conclusively, this study has provided a comprehensive understanding of the processes involved in secondary metabolites and the ability of the Talaromyces sp. DC2 strain to degrade plant cell walls.
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Affiliation(s)
- Nguyen Duc Quan
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
| | - Ngoc-Lan Nguyen
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
- Department of Biotechnology, Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam
| | - Tran Thi Huong Giang
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
| | - Nguyen Thi Thanh Ngan
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
- Department of Biotechnology, Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam
| | - Nguyen Thanh Hien
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
| | - Nguyen Van Tung
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
- Department of Biotechnology, Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam
| | - Nguyen Hoang Thanh Trang
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
| | - Nguyen Thi Kim Lien
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
- Department of Biotechnology, Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam
| | - Huy Hoang Nguyen
- Institute of Genome Research, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam; (N.D.Q.); (N.-L.N.); (T.T.H.G.); (N.T.T.N.); (N.T.H.); (N.V.T.); (N.H.T.T.); (N.T.K.L.)
- Department of Biotechnology, Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Str., Cau Giay, Hanoi 100000, Vietnam
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Tomé LMR, da Silva FF, Fonseca PLC, Mendes-Pereira T, Azevedo VADC, Brenig B, Badotti F, Góes-Neto A. Hybrid Assembly Improves Genome Quality and Completeness of Trametes villosa CCMB561 and Reveals a Huge Potential for Lignocellulose Breakdown. J Fungi (Basel) 2022; 8:jof8020142. [PMID: 35205897 PMCID: PMC8876698 DOI: 10.3390/jof8020142] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 02/06/2023] Open
Abstract
Trametes villosa is a wood-decaying fungus with great potential to be used in the bioconversion of agro-industrial residues and to obtain high-value-added products, such as biofuels. Nonetheless, the lack of high-quality genomic data hampers studies investigating genetic mechanisms and metabolic pathways in T. villosa, hindering its application in industry. Herein, applying a hybrid assembly pipeline using short reads (Illumina HiSeq) and long reads (Oxford Nanopore MinION), we obtained a high-quality genome for the T. villosa CCMB561 and investigated its genetic potential for lignocellulose breakdown. The new genome possesses 143 contigs, N50 of 1,009,271 bp, a total length of 46,748,415 bp, 14,540 protein-coding genes, 22 secondary metabolite gene clusters, and 426 genes encoding Carbohydrate-Active enzymes. Our CAZome annotation and comparative genomic analyses of nine Trametes spp. genomes revealed T. villosa CCMB561 as the species with the highest number of genes encoding lignin-modifying enzymes and a wide array of genes encoding proteins for the breakdown of cellulose, hemicellulose, and pectin. These results bring to light the potential of this isolate to be applied in the bioconversion of lignocellulose and will support future studies on the expression, regulation, and evolution of genes, proteins, and metabolic pathways regarding the bioconversion of lignocellulosic residues.
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Affiliation(s)
- Luiz Marcelo Ribeiro Tomé
- Molecular and Computational Biology of Fungi Laboratory, Department of Microbiology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil; (L.M.R.T.); (F.F.d.S.); (T.M.-P.)
| | - Felipe Ferreira da Silva
- Molecular and Computational Biology of Fungi Laboratory, Department of Microbiology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil; (L.M.R.T.); (F.F.d.S.); (T.M.-P.)
| | - Paula Luize Camargos Fonseca
- Departamento de Genética, Ecologia e Evolução, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil;
| | - Thairine Mendes-Pereira
- Molecular and Computational Biology of Fungi Laboratory, Department of Microbiology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil; (L.M.R.T.); (F.F.d.S.); (T.M.-P.)
| | - Vasco Ariston de Carvalho Azevedo
- Laboratório de Genética Celular e Molecular, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil;
| | - Bertram Brenig
- Institute of Veterinary Medicine, Burckhardtweg, University of Göttingen, 37073 Göttingen, Germany;
| | - Fernanda Badotti
- Department of Chemistry, Centro Federal de Educação Tecnológica de Minas Gerais, Belo Horizonte 30421-169, MG, Brazil;
| | - Aristóteles Góes-Neto
- Molecular and Computational Biology of Fungi Laboratory, Department of Microbiology, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil; (L.M.R.T.); (F.F.d.S.); (T.M.-P.)
- Correspondence: ; Tel.: +55-31-994130996
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Zhu X, Wang L, Zhang Z, Ding L, Hang S. Combination of fiber-degrading enzymatic hydrolysis and lactobacilli fermentation enhances utilization of fiber and protein in rapeseed meal as revealed in simulated pig digestion and fermentation in vitro. Anim Feed Sci Technol 2021. [DOI: 10.1016/j.anifeedsci.2021.115001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Xu J, Zhang H, Zheng J, Dovoedo P, Yin Y. eCAMI: simultaneous classification and motif identification for enzyme annotation. Bioinformatics 2020; 36:2068-2075. [PMID: 31794006 DOI: 10.1093/bioinformatics/btz908] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/20/2019] [Accepted: 11/30/2019] [Indexed: 11/13/2022] Open
Abstract
MOTIVATION Carbohydrate-active enzymes (CAZymes) are extremely important to bioenergy, human gut microbiome, and plant pathogen researches and industries. Here we developed a new amino acid k-mer-based CAZyme classification, motif identification and genome annotation tool using a bipartite network algorithm. Using this tool, we classified 390 CAZyme families into thousands of subfamilies each with distinguishing k-mer peptides. These k-mers represented the characteristic motifs (in the form of a collection of conserved short peptides) of each subfamily, and thus were further used to annotate new genomes for CAZymes. This idea was also generalized to extract characteristic k-mer peptides for all the Swiss-Prot enzymes classified by the EC (enzyme commission) numbers and applied to enzyme EC prediction. RESULTS This new tool was implemented as a Python package named eCAMI. Benchmark analysis of eCAMI against the state-of-the-art tools on CAZyme and enzyme EC datasets found that: (i) eCAMI has the best performance in terms of accuracy and memory use for CAZyme and enzyme EC classification and annotation; (ii) the k-mer-based tools (including PPR-Hotpep, CUPP and eCAMI) perform better than homology-based tools and deep-learning tools in enzyme EC prediction. Lastly, we confirmed that the k-mer-based tools have the unique ability to identify the characteristic k-mer peptides in the predicted enzymes. AVAILABILITY AND IMPLEMENTATION https://github.com/yinlabniu/eCAMI and https://github.com/zhanglabNKU/eCAMI. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Jing Xu
- College of Artificial Intelligence, Nankai University, Tianjin 300071, China.,College of Computer Science, Nankai University, Tianjin 300071, China
| | - Han Zhang
- College of Artificial Intelligence, Nankai University, Tianjin 300071, China
| | - Jinfang Zheng
- Department of Food Science and Technology, Nebraska Food for Health Center, University of Nebraska, Lincoln, NE 68588, USA
| | - Philippe Dovoedo
- Department of Mathematical Sciences, Northern Illinois University, DeKalb, IL 60115, USA
| | - Yanbin Yin
- Department of Food Science and Technology, Nebraska Food for Health Center, University of Nebraska, Lincoln, NE 68588, USA
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Gilchrist CLM, Lacey HJ, Vuong D, Pitt JI, Lange L, Lacey E, Pilgaard B, Chooi YH, Piggott AM. Comprehensive chemotaxonomic and genomic profiling of a biosynthetically talented Australian fungus, Aspergillus burnettii sp. nov. Fungal Genet Biol 2020; 143:103435. [PMID: 32702474 DOI: 10.1016/j.fgb.2020.103435] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 07/14/2020] [Accepted: 07/15/2020] [Indexed: 01/09/2023]
Abstract
Aspergillus burnettii is a new species belonging to the A. alliaceus clade in Aspergillus subgenus Circumdati section Flavi isolated from peanut-growing properties in southern Queensland, Australia. A. burnettii is a fast-growing, floccose fungus with distinctive brown conidia and is a talented producer of biomass-degrading enzymes and secondary metabolites. Chemical profiling of A. burnettii revealed the metabolites ochratoxin A, kotanins, isokotanins, asperlicin E, anominine and paspalinine, which are common to subgenus Circumdati, together with burnettiene A, burnettramic acids, burnettides, and high levels of 14α-hydroxypaspalinine and hirsutide. The genome of A. burnettii was sequenced and an annotated draft genome is presented. A. burnettii is rich in secondary metabolite biosynthetic gene clusters, containing 51 polyketide synthases, 28 non-ribosomal peptide synthetases and 19 genes related to terpene biosynthesis. Functional annotation of digestive enzymes of A. burnettii and A. alliaceus revealed overlapping carbon utilisation profiles, consistent with a close phylogenetic relationship.
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Affiliation(s)
- Cameron L M Gilchrist
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia
| | - Heather J Lacey
- Microbial Screening Technologies, Smithfield, NSW 2164, Australia
| | - Daniel Vuong
- Microbial Screening Technologies, Smithfield, NSW 2164, Australia
| | - John I Pitt
- Microbial Screening Technologies, Smithfield, NSW 2164, Australia
| | - Lene Lange
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark; BioEconomy, Research & Advisory, Karensgade 5, 2500 Valby, Copenhagen, Denmark
| | - Ernest Lacey
- Microbial Screening Technologies, Smithfield, NSW 2164, Australia; Department of Molecular Sciences, Macquarie University, NSW 2109, Australia
| | - Bo Pilgaard
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Yit-Heng Chooi
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia.
| | - Andrew M Piggott
- Department of Molecular Sciences, Macquarie University, NSW 2109, Australia.
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Neotropical termite microbiomes as sources of novel plant cell wall degrading enzymes. Sci Rep 2020; 10:3864. [PMID: 32123275 PMCID: PMC7052144 DOI: 10.1038/s41598-020-60850-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 12/24/2019] [Indexed: 11/08/2022] Open
Abstract
In this study, we used shotgun metagenomic sequencing to characterise the microbial metabolic potential for lignocellulose transformation in the gut of two colonies of Argentine higher termite species with different feeding habits, Cortaritermes fulviceps and Nasutitermes aquilinus. Our goal was to assess the microbial community compositions and metabolic capacity, and to identify genes involved in lignocellulose degradation. Individuals from both termite species contained the same five dominant bacterial phyla (Spirochaetes, Firmicutes, Proteobacteria, Fibrobacteres and Bacteroidetes) although with different relative abundances. However, detected functional capacity varied, with C. fulviceps (a grass-wood-feeder) gut microbiome samples containing more genes related to amino acid metabolism, whereas N. aquilinus (a wood-feeder) gut microbiome samples were enriched in genes involved in carbohydrate metabolism and cellulose degradation. The C. fulviceps gut microbiome was enriched specifically in genes coding for debranching- and oligosaccharide-degrading enzymes. These findings suggest an association between the primary food source and the predicted categories of the enzymes present in the gut microbiomes of each species. To further investigate the termite microbiomes as sources of biotechnologically relevant glycosyl hydrolases, a putative GH10 endo-β-1,4-xylanase, Xyl10E, was cloned and expressed in Escherichia coli. Functional analysis of the recombinant metagenome-derived enzyme showed high specificity towards beechwood xylan (288.1 IU/mg), with the optimum activity at 50 °C and a pH-activity range from 5 to 10. These characteristics suggest that Xy110E may be a promising candidate for further development in lignocellulose deconstruction applications.
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Zhang Y, Wang J, Yajun C, Zhou M, Wang W, Geng M, Xu D, Xu Z. Comparative Genomics Uncovers the Genetic Diversity and Synthetic Biology of Secondary Metabolite Production of Trametes. MYCOBIOLOGY 2020; 48:104-114. [PMID: 32363038 PMCID: PMC7178859 DOI: 10.1080/12298093.2020.1725361] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 01/02/2020] [Accepted: 01/22/2020] [Indexed: 05/27/2023]
Abstract
The carbohydrate-active enzyme (CAZyme) genes of Trametes contribute to polysaccharide degradation. However, the comprehensive analysis of the composition of CAZymes and the biosynthetic gene clusters (BGCs) of Trametes remain unclear. Here, we conducted comparative analysis, detected the CAZyme genes, and predicted the BGCs for nine Trametes strains. Among the 82,053 homologous clusters obtained for Trametes, we identified 8518 core genes, 60,441 accessory genes, and 13,094 specific genes. A large proportion of CAZyme genes were cataloged into glycoside hydrolases, glycosyltransferases, and carbohydrate esterases. The predicted BGCs of Trametes were divided into six strategies, and the nine Trametes strains harbored 47.78 BGCs on average. Our study revealed that Trametes exhibits an open pan-genome structure. These findings provide insights into the genetic diversity and explored the synthetic biology of secondary metabolite production for Trametes.
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Affiliation(s)
- Yan Zhang
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Jingjing Wang
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Chen Yajun
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Minghui Zhou
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Wei Wang
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Ming Geng
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Decong Xu
- School of Life Sciences, Hefei Normal University, Hefei, China
| | - Zhongdong Xu
- School of Life Sciences, Hefei Normal University, Hefei, China
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Pilgaard B, Wilkens C, Herbst FA, Vuillemin M, Rhein-Knudsen N, Meyer AS, Lange L. Proteomic enzyme analysis of the marine fungus Paradendryphiella salina reveals alginate lyase as a minimal adaptation strategy for brown algae degradation. Sci Rep 2019; 9:12338. [PMID: 31451726 PMCID: PMC6710412 DOI: 10.1038/s41598-019-48823-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 08/13/2019] [Indexed: 01/31/2023] Open
Abstract
We set out to investigate the genetic adaptations of the marine fungus Paradendryphiella salina CBS112865 for degradation of brown macroalgae. We performed whole genome and transcriptome sequencing and shotgun proteomic analysis of the secretome of P. salina grown on three species of brown algae and under carbon limitation. Genome comparison with closely related terrestrial fungi revealed that P. salina had a similar but reduced CAZyme profile relative to the terrestrial fungi except for the presence of three putative alginate lyases from Polysaccharide Lyase (PL) family 7 and a putative PL8 with similarity to ascomycete chondroitin AC lyases. Phylogenetic and homology analyses place the PL7 sequences amongst mannuronic acid specific PL7 proteins from marine bacteria. Recombinant expression, purification and characterization of one of the PL7 genes confirmed the specificity. Proteomic analysis of the P. salina secretome when growing on brown algae, revealed the PL7 and PL8 enzymes abundantly secreted together with enzymes necessary for degradation of laminarin, cellulose, lipids and peptides. Our findings indicate that the basic CAZyme repertoire of saprobic and plant pathogenic ascomycetes, with the addition of PL7 alginate lyases, provide P. salina with sufficient enzymatic capabilities to degrade several types of brown algae polysaccharides.
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Affiliation(s)
- Bo Pilgaard
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark.
| | - Casper Wilkens
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Florian-Alexander Herbst
- Center for Microbial Communities, Department of Chemistry and Bioscience Aalborg University, Aalborg, Denmark
| | - Marlene Vuillemin
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Nanna Rhein-Knudsen
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Anne S Meyer
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Lene Lange
- BioEconomy, Research & Advisory, Copenhagen, Denmark
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Carbohydrate Hydrolytic Potential and Redundancy of an Anaerobic Digestion Microbiome Exposed to Acidosis, as Uncovered by Metagenomics. Appl Environ Microbiol 2019; 85:AEM.00895-19. [PMID: 31152018 PMCID: PMC6643232 DOI: 10.1128/aem.00895-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 05/26/2019] [Indexed: 12/22/2022] Open
Abstract
The enzymatic hydrolysis of lignocellulosic biomass is mainly driven by the action of carbohydrate-active enzymes. By characterizing the gene profiles at the different stages of the anaerobic digestion experiment, we showed that the microbiome retains its hydrolytic functional redundancy even during severe acidosis, despite significant changes in taxonomic composition. By analyzing reconstructed bacterial genomes, we demonstrate that Bacteroidetes hydrolytic gene diversity likely favors the abundance of this phylum in some anaerobic digestion systems. Further, we observe genetic redundancy within the Bacteroidetes group, which accounts for the preserved hydrolytic potential during acidosis. This work also uncovers new polysaccharide utilization loci involved in the deconstruction of various biomasses and proposes the model of acetylated glucomannan degradation by Bacteroidetes. Acetylated glucomannan-enriched biomass is a common substrate for many industries, including pulp and paper production. Using naturally evolved cocktails of enzymes for biomass pretreatment could be an interesting alternative to the commonly used chemical pretreatments. Increased hydrolysis of easily digestible biomass may lead to acidosis of anaerobic reactors and decreased methane production. Previously, it was shown that the structure of microbial communities changed during acidosis; however, once the conditions are back to optimal, biogas (initially CO2) production quickly restarts. This suggests the retention of the community functional redundancy during the process failure. In this study, with the use of metagenomics and downstream bioinformatics analyses, we characterize the carbohydrate hydrolytic potential of the microbial community, with a special focus on acidosis. To that purpose, carbohydrate-active enzymes were identified, and to further link the community hydrolytic potential with key microbes, bacterial genomes were reconstructed. In addition, we characterized biochemically the specificity and activity of selected enzymes, thus verifying the accuracy of the in silico predictions. The results confirm the retention of the community hydrolytic potential during acidosis and indicate Bacteroidetes to be largely involved in biomass degradation. Bacteroidetes showed higher diversity and genomic content of carbohydrate hydrolytic enzymes that might favor the dominance of this phylum over other bacteria in some anaerobic reactors. The combination of bioinformatic analyses and activity tests enabled us to propose a model of acetylated glucomannan degradation by Bacteroidetes. IMPORTANCE The enzymatic hydrolysis of lignocellulosic biomass is mainly driven by the action of carbohydrate-active enzymes. By characterizing the gene profiles at the different stages of the anaerobic digestion experiment, we showed that the microbiome retains its hydrolytic functional redundancy even during severe acidosis, despite significant changes in taxonomic composition. By analyzing reconstructed bacterial genomes, we demonstrate that Bacteroidetes hydrolytic gene diversity likely favors the abundance of this phylum in some anaerobic digestion systems. Further, we observe genetic redundancy within the Bacteroidetes group, which accounts for the preserved hydrolytic potential during acidosis. This work also uncovers new polysaccharide utilization loci involved in the deconstruction of various biomasses and proposes the model of acetylated glucomannan degradation by Bacteroidetes. Acetylated glucomannan-enriched biomass is a common substrate for many industries, including pulp and paper production. Using naturally evolved cocktails of enzymes for biomass pretreatment could be an interesting alternative to the commonly used chemical pretreatments.
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Abstract
Understanding functional capacities of gut microbiomes is important to improve our understanding of symbiotic associations. Here, we use peptide-based functional annotation to show that the gut microbiomes of fungus-farming termites code for a wealth of enzymes that likely target the fungal diet the termites eat. Comparisons to other termites showed that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, whereas wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Across termites with different diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community compositions. Termites forage on a range of substrates, and it has been suggested that diet shapes the composition and function of termite gut bacterial communities. Through comparative analyses of gut metagenomes in nine termite species with distinct diets, we characterize bacterial community compositions and use peptide-based functional annotation method to determine biomass-degrading enzymes and the bacterial taxa that encode them. We find that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, while wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Interestingly, wood-feeding termite gut bacterial genes code for abundant chitinolytic enzymes, suggesting that fungal biomass within the decaying wood likely contributes to gut bacterial or termite host nutrition. Across diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community composition, with the most marked difference being the communities coding for the mycolytic capacity of the fungus-growing termite gut. IMPORTANCE Understanding functional capacities of gut microbiomes is important to improve our understanding of symbiotic associations. Here, we use peptide-based functional annotation to show that the gut microbiomes of fungus-farming termites code for a wealth of enzymes that likely target the fungal diet the termites eat. Comparisons to other termites showed that fungus-growing termite guts have relatively more fungal cell wall-degrading enzyme genes, whereas wood-feeding termite gut communities have relatively more plant cell wall-degrading enzyme genes. Across termites with different diets, the dominant biomass-degrading enzymes are predominantly coded for by the most abundant bacterial taxa, suggesting tight links between diet and gut community compositions.
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Thornbury M, Sicheri J, Slaine P, Getz LJ, Finlayson-Trick E, Cook J, Guinard C, Boudreau N, Jakeman D, Rohde J, McCormick C. Characterization of novel lignocellulose-degrading enzymes from the porcupine microbiome using synthetic metagenomics. PLoS One 2019; 14:e0209221. [PMID: 30601862 PMCID: PMC6314593 DOI: 10.1371/journal.pone.0209221] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 11/30/2018] [Indexed: 12/22/2022] Open
Abstract
Plant cell walls are composed of cellulose, hemicellulose, and lignin, collectively known as lignocellulose. Microorganisms degrade lignocellulose to liberate sugars to meet metabolic demands. Using a metagenomic sequencing approach, we previously demonstrated that the microbiome of the North American porcupine (Erethizon dorsatum) is replete with genes that could encode lignocellulose-degrading enzymes. Here, we report the identification, synthesis and partial characterization of four novel genes from the porcupine microbiome encoding putative lignocellulose-degrading enzymes: β-glucosidase, α-L-arabinofuranosidase, β-xylosidase, and endo-1,4-β-xylanase. These genes were identified via conserved catalytic domains associated with cellulose- and hemicellulose-degradation. Phylogenetic trees were created for each of these putative enzymes to depict genetic relatedness to known enzymes. Candidate genes were synthesized and cloned into plasmid expression vectors for inducible protein expression and secretion. The putative β-glucosidase fusion protein was efficiently secreted but did not permit Escherichia coli (E. coli) to use cellobiose as a sole carbon source, nor did the affinity purified enzyme cleave p-Nitrophenyl β-D-glucopyranoside (p-NPG) substrate in vitro over a range of physiological pH levels (pH 5–7). The putative hemicellulose-degrading β-xylosidase and α-L-arabinofuranosidase enzymes also lacked in vitro enzyme activity, but the affinity purified endo-1,4-β-xylanase protein cleaved a 6-chloro-4-methylumbelliferyl xylobioside substrate in acidic and neutral conditions, with maximal activity at pH 7. At this optimal pH, KM, Vmax, and kcat were determined to be 32.005 ± 4.72 μM, 1.16x10-5 ± 3.55x10-7 M/s, and 94.72 s-1, respectively. Thus, our pipeline enabled successful identification and characterization of a novel hemicellulose-degrading enzyme from the porcupine microbiome. Progress towards the goal of introducing a complete lignocellulose-degradation pathway into E. coli will be accelerated by combining synthetic metagenomic approaches with functional metagenomic library screening, which can identify novel enzymes unrelated to those found in available databases.
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Affiliation(s)
- Mackenzie Thornbury
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jacob Sicheri
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Patrick Slaine
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Landon J. Getz
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Emma Finlayson-Trick
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jamie Cook
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Caroline Guinard
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Nicholas Boudreau
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - David Jakeman
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada
- College of Pharmacy, Dalhousie University, Halifax, Nova Scotia, Canada
| | - John Rohde
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Craig McCormick
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
- * E-mail:
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Lange L, Pilgaard B, Herbst FA, Busk PK, Gleason F, Pedersen AG. Origin of fungal biomass degrading enzymes: Evolution, diversity and function of enzymes of early lineage fungi. FUNGAL BIOL REV 2019. [DOI: 10.1016/j.fbr.2018.09.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Cellulase production by white-rot basidiomycetous fungi: solid-state versus submerged cultivation. Appl Microbiol Biotechnol 2018; 102:5827-5839. [PMID: 29766241 DOI: 10.1007/s00253-018-9072-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 04/28/2018] [Accepted: 05/01/2018] [Indexed: 10/16/2022]
Abstract
White-rot basidiomycetous (WRB) fungi are a group of wood-decaying fungi that are known to be endowed with the ability to secrete enzymes that can catalyze decomposition of a range of plant cell wall polysaccharides, including cellulose and lignin. Expression of these enzymes is induced by the substrate and the enzyme yields obtained depend on the growth of the fungi and thus the mode of cultivation. In order to exploit WRB fungi for local enzyme production for converting lignocellulosic materials in biorefinery processes, the fungi can principally be cultivated in either solid-state (SSC) or submerged cultivation (SmC) systems. In this review, we quantitatively assess the data available in the literature on cellulase production yields by WRB fungi cultivated by SSC or SmC. The review also assesses cellulolytic enzyme production rates and enzyme recovery when WRB fungi are cultivated on different biomass residues in SSC or SmC systems. Although some variation in cellulase production yields have been reported for certain substrates, the analysis convincingly shows that SmC is generally more efficient than SSC for obtaining high cellulase production yields and high cellulase production rates on the substrate used. However, the cultivation method also affects the enzyme activity profile obtained, and the resulting enzyme titers and significant dilution of the enzymes usually occurs in SmC. The review also highlights some future approaches, including sequential cultivations and co-cultivation of WRB fungi for improved enzyme expression, as well as on-site approaches for production of enzyme blends for industrial biomass conversion. The quantitative comparisons made have implications for selection of the most appropriate cultivation method for WRB fungi for attaining maximal cellulase production.
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Godoy AS, Pereira CS, Ramia MP, Silveira RL, Camilo CM, Kadowaki MA, Lange L, Busk PK, Nascimento AS, Skaf MS, Polikarpov I. Structure, computational and biochemical analysis of PcCel45A endoglucanase from Phanerochaete chrysosporium and catalytic mechanisms of GH45 subfamily C members. Sci Rep 2018; 8:3678. [PMID: 29487297 PMCID: PMC5829257 DOI: 10.1038/s41598-018-21798-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 01/23/2018] [Indexed: 11/09/2022] Open
Abstract
The glycoside hydrolase family 45 (GH45) of carbohydrate modifying enzymes is mostly comprised of β-1,4-endoglucanases. Significant diversity between the GH45 members has prompted the division of this family into three subfamilies: A, B and C, which may differ in terms of the mechanism, general architecture, substrate binding and cleavage. Here, we use a combination of X-ray crystallography, bioinformatics, enzymatic assays, molecular dynamics simulations and site-directed mutagenesis experiments to characterize the structure, substrate binding and enzymatic specificity of the GH45 subfamily C endoglucanase from Phanerochaete chrysosporium (PcCel45A). We investigated the role played by different residues in the binding of the enzyme to cellulose oligomers of different lengths and examined the structural characteristics and dynamics of PcCel45A that make subfamily C so dissimilar to other members of the GH45 family. Due to the structural similarity shared between PcCel45A and domain I of expansins, comparative analysis of their substrate binding was also carried out. Our bioinformatics sequence analyses revealed that the hydrolysis mechanisms in GH45 subfamily C is not restricted to use of the imidic asparagine as a general base in the "Newton's cradle" catalytic mechanism recently proposed for this subfamily.
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Affiliation(s)
- Andre S Godoy
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, São Paulo, Brazil
| | - Caroline S Pereira
- Institute of Chemistry, University of Campinas, Campinas, 13084-862, São Paulo, Brazil
| | - Marina Paglione Ramia
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, São Paulo, Brazil
| | - Rodrigo L Silveira
- Institute of Chemistry, University of Campinas, Campinas, 13084-862, São Paulo, Brazil
| | - Cesar M Camilo
- Centro de Tecnologia Canavieira, Fazenda Santo Antonio, PO Box 162, 13400-970, Piracicaba, São Paulo, Brazil
| | - Marco A Kadowaki
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, São Paulo, Brazil
| | - Lene Lange
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, 2800 Kgs, Lyngby, Denmark
| | - Peter K Busk
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, 2800 Kgs, Lyngby, Denmark
| | - Alessandro S Nascimento
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, São Paulo, Brazil
| | - Munir S Skaf
- Institute of Chemistry, University of Campinas, Campinas, 13084-862, São Paulo, Brazil
| | - Igor Polikarpov
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13566-590, São Paulo, Brazil.
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Genome mining for peptidases in heat-tolerant and mesophilic fungi and putative adaptations for thermostability. BMC Genomics 2018; 19:152. [PMID: 29463214 PMCID: PMC5819190 DOI: 10.1186/s12864-018-4549-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 02/13/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Peptidases (EC 3.4) consist of a large group of hydrolytic enzymes that catalyze the hydrolysis of proteins accounting for approximately 65% of the total worldwide enzyme production. Peptidases from thermophilic fungi have adaptations to high temperature that makes them adequate for biotechnological application. In the present study, we profiled the genomes of heat-tolerant fungi and phylogenetically related mesophilic species for genes encoding for peptidases and their putative adaptations for thermostability. RESULTS We generated an extensive catalogue of these enzymes ranging from 241 to 820 peptidase genes in the genomes of 23 fungi. Thermophilic species presented the smallest number of peptidases encoding genes in relation to mesophilic species, and the peptidases families with a greater number of genes were the most affected. We observed differences in peptidases in thermophilic species in comparison to mesophilic counterparts, at (i) the genome level: a great reduction in the number of peptidases encoding genes that harbored a higher number of copies; (ii) in the primary protein structure: shifts in proportion of single or groups of amino acids; and (iii) in the three-dimensional structure: reduction in the number of internal cavities. Similar results were reported for extremely thermophilic proteins, but here we show for the first time that several changes also occurred on the moderate thermophilic enzymes of fungi. In regards to the amino acids composition, peptidases from thermophilic species in relation to the mesophilic ones, contained a larger proportion of Ala, Glu, Gly, Pro, Arg and Val residues and a lower number of Cys, His, Ile, Lys, Met, Asn, Gln, Ser, Thr and Trp residues (P < 0.05). Moreover, we observed an increase in the proportion of hydrophobic and charged amino acids and a decrease in polar amino acids. CONCLUSIONS Although thermophilic fungi present less genes encoding for peptidases, these have adaptations that could play a role in thermal resistance from genome to protein structure level.
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Enzyme Activities at Different Stages of Plant Biomass Decomposition in Three Species of Fungus-Growing Termites. Appl Environ Microbiol 2018; 84:AEM.01815-17. [PMID: 29269491 PMCID: PMC5812949 DOI: 10.1128/aem.01815-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 12/07/2017] [Indexed: 11/20/2022] Open
Abstract
Fungus-growing termites rely on mutualistic fungi of the genus Termitomyces and gut microbes for plant biomass degradation. Due to a certain degree of symbiont complementarity, this tripartite symbiosis has evolved as a complex bioreactor, enabling decomposition of nearly any plant polymer, likely contributing to the success of the termites as one of the main plant decomposers in the Old World. In this study, we evaluated which plant polymers are decomposed and which enzymes are active during the decomposition process in two major genera of fungus-growing termites. We found a diversity of active enzymes at different stages of decomposition and a consistent decrease in plant components during the decomposition process. Furthermore, our findings are consistent with the hypothesis that termites transport enzymes from the older mature parts of the fungus comb through young worker guts to freshly inoculated plant substrate. However, preliminary fungal RNA sequencing (RNA-seq) analyses suggest that this likely transport is supplemented with enzymes produced in situ. Our findings support that the maintenance of an external fungus comb, inoculated with an optimal mixture of plant material, fungal spores, and enzymes, is likely the key to the extraordinarily efficient plant decomposition in fungus-growing termites. IMPORTANCE Fungus-growing termites have a substantial ecological footprint in the Old World (sub)tropics due to their ability to decompose dead plant material. Through the establishment of an elaborate plant biomass inoculation strategy and through fungal and bacterial enzyme contributions, this farming symbiosis has become an efficient and versatile aerobic bioreactor for plant substrate conversion. Since little is known about what enzymes are expressed and where they are active at different stages of the decomposition process, we used enzyme assays, transcriptomics, and plant content measurements to shed light on how this decomposition of plant substrate is so effectively accomplished.
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17
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Wilding M, Nachtschatt M, Speight R, Scott C. An improved and general streamlined phylogenetic protocol applied to the fatty acid desaturase family. Mol Phylogenet Evol 2017; 115:50-57. [PMID: 28739372 DOI: 10.1016/j.ympev.2017.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/13/2017] [Accepted: 07/19/2017] [Indexed: 11/16/2022]
Abstract
Numerous tools to generate phylogenetic estimates are available, but there is no single protocol that will produce an accurate phylogenetic tree for any dataset. Here, we investigated some of those tools, paying particular attention to different alignment algorithms, in order to produce a phylogeny for the integral membrane fatty acid desaturase (FAD) family. Herein, we report a novel streamlined protocol which utilises peptide pattern recognition (PPR). This protocol can theoretically be applied universally to generate accurate multiple sequence alignments and improve downstream phylogenetic analyses. Applied to the desaturases, the protocol generated the first detailed phylogenetic estimates for the family since 2003, which suggested they may have evolved from three functionally distinct desaturases and further, that desaturases evolved first in cyanobacteria. In addition to the phylogenetic outputs, we mapped PPR sequence motifs onto an X-ray protein structure to provide insights into biochemical function and demonstrate the complementarity of PPR and phylogenetics.
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Affiliation(s)
- Matthew Wilding
- CSIRO Land and Water, Black Mountain, Canberra, ACT 2601, Australia.
| | - Matthias Nachtschatt
- CSIRO Land and Water, Black Mountain, Canberra, ACT 2601, Australia; Queensland University of Technology (QUT), Brisbane, QLD 4001, Australia
| | - Robert Speight
- Queensland University of Technology (QUT), Brisbane, QLD 4001, Australia
| | - Colin Scott
- CSIRO Land and Water, Black Mountain, Canberra, ACT 2601, Australia
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18
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Abstract
Fungi and fungal enzymes play important roles in the new bioeconomy. Enzymes from filamentous fungi can unlock the potential of recalcitrant lignocellulose structures of plant cell walls as a new resource, and fungi such as yeast can produce bioethanol from the sugars released after enzyme treatment. Such processes reflect inherent characteristics of the fungal way of life, namely, that fungi as heterotrophic organisms must break down complex carbon structures of organic materials to satisfy their need for carbon and nitrogen for growth and reproduction. This chapter describes major steps in the conversion of plant biomass to value-added products. These products provide a basis for substituting fossil-derived fuels, chemicals, and materials, as well as unlocking the biomass potential of the agricultural harvest to yield more food and feed. This article focuses on the mycological basis for the fungal contribution to biorefinery processes, which are instrumental for improved resource efficiency and central to the new bioeconomy. Which types of processes, inherent to fungal physiology and activities in nature, are exploited in the new industrial processes? Which families of the fungal kingdom and which types of fungal habitats and ecological specializations are hot spots for fungal biomass conversion? How can the best fungal enzymes be found and optimized for industrial use? How can they be produced most efficiently-in fungal expression hosts? How have industrial biotechnology and biomass conversion research contributed to mycology and environmental research? Future perspectives and approaches are listed, highlighting the importance of fungi in development of the bioeconomy.
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19
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Abstract
The diversity and abundance of zoosporic true fungi have been analyzed recently using fungal sequence libraries and advances in molecular methods, such as high-throughput sequencing. This review focuses on four evolutionary primitive true fungal phyla: the Aphelidea, Chytridiomycota, Neocallimastigomycota, and Rosellida (Cryptomycota), most species of which are not polycentric or mycelial (filamentous), rather they tend to be primarily monocentric (unicellular). Zoosporic fungi appear to be both abundant and diverse in many aquatic habitats around the world, with abundance often exceeding other fungal phyla in these habitats, and numerous novel genetic sequences identified. Zoosporic fungi are able to survive extreme conditions, such as high and extremely low pH; however, more work remains to be done. They appear to have important ecological roles as saprobes in decomposition of particulate organic substrates, pollen, plant litter, and dead animals; as parasites of zooplankton and algae; as parasites of vertebrate animals (such as frogs); and as symbionts in the digestive tracts of mammals. Some chytrids cause economically important diseases of plants and animals. They regulate sizes of phytoplankton populations. Further metagenomics surveys of aquatic ecosystems are expected to enlarge our knowledge of the diversity of true zoosporic fungi. Coupled with studies on their functional ecology, we are moving closer to unraveling the role of zoosporic fungi in carbon cycling and the impact of climate change on zoosporic fungal populations.
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Homology to peptide pattern for annotation of carbohydrate-active enzymes and prediction of function. BMC Bioinformatics 2017; 18:214. [PMID: 28403817 PMCID: PMC5389127 DOI: 10.1186/s12859-017-1625-9] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 04/05/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Carbohydrate-active enzymes are found in all organisms and participate in key biological processes. These enzymes are classified in 274 families in the CAZy database but the sequence diversity within each family makes it a major task to identify new family members and to provide basis for prediction of enzyme function. A fast and reliable method for de novo annotation of genes encoding carbohydrate-active enzymes is to identify conserved peptides in the curated enzyme families followed by matching of the conserved peptides to the sequence of interest as demonstrated for the glycosyl hydrolase and the lytic polysaccharide monooxygenase families. This approach not only assigns the enzymes to families but also provides functional prediction of the enzymes with high accuracy. RESULTS We identified conserved peptides for all enzyme families in the CAZy database with Peptide Pattern Recognition. The conserved peptides were matched to protein sequence for de novo annotation and functional prediction of carbohydrate-active enzymes with the Hotpep method. Annotation of protein sequences from 12 bacterial and 16 fungal genomes to families with Hotpep had an accuracy of 0.84 (measured as F1-score) compared to semiautomatic annotation by the CAZy database whereas the dbCAN HMM-based method had an accuracy of 0.77 with optimized parameters. Furthermore, Hotpep provided a functional prediction with 86% accuracy for the annotated genes. Hotpep is available as a stand-alone application for MS Windows. CONCLUSIONS Hotpep is a state-of-the-art method for automatic annotation and functional prediction of carbohydrate-active enzymes.
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Aspergillus hancockii sp. nov., a biosynthetically talented fungus endemic to southeastern Australian soils. PLoS One 2017; 12:e0170254. [PMID: 28379953 PMCID: PMC5381763 DOI: 10.1371/journal.pone.0170254] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/29/2016] [Indexed: 12/18/2022] Open
Abstract
Aspergillus hancockii sp. nov., classified in Aspergillus subgenus Circumdati section Flavi, was originally isolated from soil in peanut fields near Kumbia, in the South Burnett region of southeast Queensland, Australia, and has since been found occasionally from other substrates and locations in southeast Australia. It is phylogenetically and phenotypically related most closely to A. leporis States and M. Chr., but differs in conidial colour, other minor features and particularly in metabolite profile. When cultivated on rice as an optimal substrate, A. hancockii produced an extensive array of 69 secondary metabolites. Eleven of the 15 most abundant secondary metabolites, constituting 90% of the total area under the curve of the HPLC trace of the crude extract, were novel. The genome of A. hancockii, approximately 40 Mbp, was sequenced and mined for genes encoding carbohydrate degrading enzymes identified the presence of more than 370 genes in 114 gene clusters, demonstrating that A. hancockii has the capacity to degrade cellulose, hemicellulose, lignin, pectin, starch, chitin, cutin and fructan as nutrient sources. Like most Aspergillus species, A. hancockii exhibited a diverse secondary metabolite gene profile, encoding 26 polyketide synthase, 16 nonribosomal peptide synthase and 15 nonribosomal peptide synthase-like enzymes.
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Agger JW, Busk PK, Pilgaard B, Meyer AS, Lange L. A New Functional Classification of Glucuronoyl Esterases by Peptide Pattern Recognition. Front Microbiol 2017; 8:309. [PMID: 28293230 PMCID: PMC5329029 DOI: 10.3389/fmicb.2017.00309] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/14/2017] [Indexed: 12/21/2022] Open
Abstract
Glucuronoyl esterases are a novel type of enzymes believed to catalyze the hydrolysis of ester linkages between lignin and glucuronoxylan in lignocellulosic biomass, linkages known as lignin carbohydrate complexes. These complexes contribute to the recalcitrance of lignocellulose. Glucuronoyl esterases are a part of the microbial machinery for lignocellulose degradation and coupling their role to the occurrence of lignin carbohydrate complexes in biomass is a desired research goal. Glucuronoyl esterases have been assigned to CAZymes family 15 of carbohydrate esterases, but only few examples of characterized enzymes exist and the exact activity is still uncertain. Here peptide pattern recognition is used as a bioinformatic tool to identify and group new CE15 proteins that are likely to have glucuronoyl esterase activity. 1024 CE15-like sequences were drawn from GenBank and grouped into 24 groups. Phylogenetic analysis of these groups made it possible to pinpoint groups of putative fungal and bacterial glucuronoyl esterases and their sequence variation. Moreover, a number of groups included previously undescribed CE15-like sequences that are distinct from the glucuronoyl esterases and may possibly have different esterase activity. Hence, the CE15 family is likely to comprise other enzyme functions than glucuronoyl esterase alone. Gene annotation in a variety of fungal and bacterial microorganisms showed that coprophilic fungi are rich and diverse sources of CE15 proteins. Combined with the lifestyle and habitat of coprophilic fungi, they are predicted to be excellent candidates for finding new glucuronoyl esterase genes.
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Affiliation(s)
- Jane W Agger
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark Lyngby, Denmark
| | - Peter K Busk
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark Lyngby, Denmark
| | - Bo Pilgaard
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark Lyngby, Denmark
| | - Anne S Meyer
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark Lyngby, Denmark
| | - Lene Lange
- Center for BioProcess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark Lyngby, Denmark
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Efficient screening of potential cellulases and hemicellulases produced by Bosea sp. FBZP-16 using the combination of enzyme assays and genome analysis. World J Microbiol Biotechnol 2017; 33:29. [PMID: 28058637 DOI: 10.1007/s11274-016-2198-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 12/22/2016] [Indexed: 10/20/2022]
Abstract
Identification of bacteria that produce carbohydrolytic enzymes is extremely important given the increased demand for these enzymes in many industries. Twenty lignocellulose-degrading bacterial isolates from Algerian compost and different soils were screened for their potential to produce different enzymes involved in biomass deconstruction. Based on 16S rRNA gene sequencing, the isolates belonged to Proteobacteria and Actinobacteria. Differences among species were reflected both as the presence/absence of enzymes or at the level of enzyme activity. Among the most active species, Bosea sp. FBZP-16 demonstrated cellulolytic activity on both amorphous cellulose (CMC) and complex lignocellulose (wheat straw) and was selected for whole-genomic sequencing. The genome sequencing revealed the presence of a complex enzymatic machinery required for organic matter decomposition. Analysis of the enzyme-encoding genes indicated that multiple genes for endoglucanase, xylanase, β-glucosidase and β-mannosidase are present in the genome with enzyme activities displayed by the bacterium, while other enzymes, such as certain cellobiohydrolases, were not detected at the genomic level. This indicates that a combination of functional screening of bacterial cultures with the use of genome-derived information is important for the prediction of potential enzyme production. These results provide insight into their possible exploitation for the production of fuels and chemicals derived from plant biomass.
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Wilkens C, Busk PK, Pilgaard B, Zhang WJ, Nielsen KL, Nielsen PH, Lange L. Diversity of microbial carbohydrate-active enzymes in Danish anaerobic digesters fed with wastewater treatment sludge. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:158. [PMID: 28649277 PMCID: PMC5480151 DOI: 10.1186/s13068-017-0840-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
BACKGROUND Improved carbohydrate-active enzymes (CAZymes) are needed to fulfill the goal of producing food, feed, fuel, chemicals, and materials from biomass. Little is known about how the diverse microbial communities in anaerobic digesters (ADs) metabolize carbohydrates or which CAZymes that are present, making the ADs a unique niche to look for CAZymes that can potentiate the enzyme blends currently used in industry. RESULTS Enzymatic assays showed that functional CAZymes were secreted into the AD environments in four full-scale mesophilic Danish ADs fed with primary and surplus sludge from municipal wastewater treatment plants. Metagenomes from the ADs were mined for CAZymes with Homology to Peptide Patterns (HotPep). 19,335 CAZymes were identified of which 30% showed 50% or lower identity to known proteins demonstrating that ADs make up a promising pool for discovery of novel CAZymes. A function was assigned to 54% of all CAZymes identified by HotPep. Many different α-glucan-acting CAZymes were identified in the four metagenomes, and the most abundant family was glycoside hydrolase family 13, which contains α-glucan-acting CAZymes. Cellulytic and xylanolytic CAZymes were also abundant in the four metagenomes. The cellulytic enzymes were limited almost to endoglucanases and β-glucosidases, which reflect the large amount of partly degraded cellulose in the sludge. No dockerin domains were identified suggesting that the cellulytic enzymes in the ADs studied operate independently. Of xylanolytic CAZymes, especially xylanases and β-xylosidase, but also a battery of accessory enzymes, were present in the four ADs. CONCLUSIONS Our findings suggest that the ADs are a good place to look for novel plant biomass degrading and modifying enzymes that can potentiate biological processes and provide basis for production of a range of added-value products from biorefineries.
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Affiliation(s)
- Casper Wilkens
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, 2800 Kongens Lyngby, Denmark
| | - Peter Kamp Busk
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, 2800 Kongens Lyngby, Denmark
| | - Bo Pilgaard
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, 2800 Kongens Lyngby, Denmark
| | - Wen-Jing Zhang
- Section for Sustainable Biotechnology, Department of Chemistry and Bioscience, Aalborg University, A. C. Meyers Vænge 15, 2450 Copenhagen, Denmark
- Department of Animal Sciences, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - Kåre L. Nielsen
- Center for Microbial Communities, Section for Biotechnology, Department of Chemistry and Bioscience, Aalborg University, Frederiks Bajer Vej 7, 9220 Aalborg, Denmark
| | - Per Halkjær Nielsen
- Center for Microbial Communities, Section for Biotechnology, Department of Chemistry and Bioscience, Aalborg University, Frederiks Bajer Vej 7, 9220 Aalborg, Denmark
| | - Lene Lange
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, 2800 Kongens Lyngby, Denmark
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Lange L, Huang Y, Busk PK. Microbial decomposition of keratin in nature-a new hypothesis of industrial relevance. Appl Microbiol Biotechnol 2016; 100:2083-96. [PMID: 26754820 PMCID: PMC4756042 DOI: 10.1007/s00253-015-7262-1] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/16/2015] [Accepted: 12/19/2015] [Indexed: 11/28/2022]
Abstract
Discovery of keratin-degrading enzymes from fungi and bacteria has primarily focused on finding one protease with efficient keratinase activity. Recently, an investigation was conducted of all keratinases secreted from a fungus known to grow on keratinaceous materials, such as feather, horn, and hooves. The study demonstrated that a minimum of three keratinases is needed to break down keratin, an endo-acting, an exo-acting, and an oligopeptide-acting keratinase. Further, several studies have documented that disruption of sulfur bridges of the keratin structure acts synergistically with the keratinases to loosen the molecular structure, thus giving the enzymes access to their substrate, the protein structure. With such complexity, it is relevant to compare microbial keratin decomposition with the microbial decomposition of well-studied polymers such as cellulose and chitin. Interestingly, it was recently shown that the specialized enzymes, lytic polysaccharide monoxygenases (LPMOs), shown to be important for breaking the recalcitrance of cellulose and chitin, are also found in keratin-degrading fungi. A holistic view of the complex molecular self-assembling structure of keratin and knowledge about enzymatic and boosting factors needed for keratin breakdown have been used to formulate a hypothesis for mode of action of the LPMOs in keratin decomposition and for a model for degradation of keratin in nature. Testing such hypotheses and models still needs to be done. Even now, the hypothesis can serve as an inspiration for designing industrial processes for keratin decomposition for conversion of unexploited waste streams, chicken feather, and pig bristles into bioaccessible animal feed.
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Affiliation(s)
- Lene Lange
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800, Lyngby, Denmark.
| | - Yuhong Huang
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800, Lyngby, Denmark
| | - Peter Kamp Busk
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800, Lyngby, Denmark
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Alic AS, Ruzafa D, Dopazo J, Blanquer I. Objective review of de novostand-alone error correction methods for NGS data. WILEY INTERDISCIPLINARY REVIEWS: COMPUTATIONAL MOLECULAR SCIENCE 2016. [DOI: 10.1002/wcms.1239] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Andy S. Alic
- Institute of Instrumentation for Molecular Imaging (I3M); Universitat Politècnica de València; València Spain
| | - David Ruzafa
- Departamento de Quìmica Fìsica e Instituto de Biotecnologìa, Facultad de Ciencias; Universidad de Granada; Granada Spain
| | - Joaquin Dopazo
- Department of Computational Genomics; Príncipe Felipe Research Centre (CIPF); Valencia Spain
- CIBER de Enfermedades Raras (CIBERER); Valencia Spain
- Functional Genomics Node (INB) at CIPF; Valencia Spain
| | - Ignacio Blanquer
- Institute of Instrumentation for Molecular Imaging (I3M); Universitat Politècnica de València; València Spain
- Biomedical Imaging Research Group GIBI 2; Polytechnic University Hospital La Fe; Valencia Spain
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Acidic–alkaline ferulic acid esterase from Chaetomium thermophilum var. dissitum: Molecular cloning and characterization of recombinant enzyme expressed in Pichia pastoris. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2016. [DOI: 10.1016/j.bcab.2015.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Cragg SM, Beckham GT, Bruce NC, Bugg TDH, Distel DL, Dupree P, Etxabe AG, Goodell BS, Jellison J, McGeehan JE, McQueen-Mason SJ, Schnorr K, Walton PH, Watts JEM, Zimmer M. Lignocellulose degradation mechanisms across the Tree of Life. Curr Opin Chem Biol 2015; 29:108-19. [PMID: 26583519 PMCID: PMC7571853 DOI: 10.1016/j.cbpa.2015.10.018] [Citation(s) in RCA: 297] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 10/11/2015] [Accepted: 10/14/2015] [Indexed: 12/13/2022]
Abstract
Organisms use diverse mechanisms involving multiple complementary enzymes, particularly glycoside hydrolases (GHs), to deconstruct lignocellulose. Lytic polysaccharide monooxygenases (LPMOs) produced by bacteria and fungi facilitate deconstruction as does the Fenton chemistry of brown-rot fungi. Lignin depolymerisation is achieved by white-rot fungi and certain bacteria, using peroxidases and laccases. Meta-omics is now revealing the complexity of prokaryotic degradative activity in lignocellulose-rich environments. Protists from termite guts and some oomycetes produce multiple lignocellulolytic enzymes. Lignocellulose-consuming animals secrete some GHs, but most harbour a diverse enzyme-secreting gut microflora in a mutualism that is particularly complex in termites. Shipworms however, house GH-secreting and LPMO-secreting bacteria separate from the site of digestion and the isopod Limnoria relies on endogenous enzymes alone. The omics revolution is identifying many novel enzymes and paradigms for biomass deconstruction, but more emphasis on function is required, particularly for enzyme cocktails, in which LPMOs may play an important role.
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Affiliation(s)
- Simon M Cragg
- School of Biological Sciences, University of Portsmouth, King Henry Building, King Henry 1st St., Portsmouth PO1 2DY, UK.
| | - Gregg T Beckham
- National Renewable Energy Laboratory, National Bioenergy Centre, Golden, CO 80401 USA
| | - Neil C Bruce
- University of York, Department of Biological Sciences, Centre for Novel Agricultural Products, York YO10 5DD, UK
| | - Timothy D H Bugg
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK
| | - Daniel L Distel
- Ocean Genome Legacy, Marine Science Center, Northeastern University, Boston, MA, USA
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Hopkins Building, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Amaia Green Etxabe
- School of Biological Sciences, University of Portsmouth, King Henry Building, King Henry 1st St., Portsmouth PO1 2DY, UK
| | - Barry S Goodell
- Department of Sustainable Biomaterials, 216 ICTAS II Bldg., Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA
| | - Jody Jellison
- Department of Plant Pathology, Physiology and Weed Science, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA
| | - John E McGeehan
- School of Biological Sciences, University of Portsmouth, King Henry Building, King Henry 1st St., Portsmouth PO1 2DY, UK
| | - Simon J McQueen-Mason
- University of York, Department of Biological Sciences, Centre for Novel Agricultural Products, York YO10 5DD, UK
| | | | - Paul H Walton
- Department of Chemistry, University of York, York YO10 5DD, UK
| | - Joy E M Watts
- School of Biological Sciences, University of Portsmouth, King Henry Building, King Henry 1st St., Portsmouth PO1 2DY, UK
| | - Martin Zimmer
- Leibniz-Center for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitstrasse 6, 28359 Bremen, Germany
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Tong X, Busk PK, Lange L. Characterization of a newsn-1,3-regioselective triacylglycerol lipase fromMalbranchea cinnamomea. Biotechnol Appl Biochem 2015; 63:471-8. [DOI: 10.1002/bab.1394] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 05/05/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Xiaoxue Tong
- Section for Sustainable Biotechnology; Department of Chemistry and Bioscience; Aalborg University Copenhagen; Denmark
| | - Peter Kamp Busk
- Section for Sustainable Biotechnology; Department of Chemistry and Bioscience; Aalborg University Copenhagen; Denmark
- Barentzymes A/S; A C Meyers Vaenge 15; Copenhagen SV Denmark
| | - Lene Lange
- Section for Sustainable Biotechnology; Department of Chemistry and Bioscience; Aalborg University Copenhagen; Denmark
- Barentzymes A/S; A C Meyers Vaenge 15; Copenhagen SV Denmark
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Huang Y, Busk PK, Lange L. Cellulose and hemicellulose-degrading enzymes in Fusarium commune transcriptome and functional characterization of three identified xylanases. Enzyme Microb Technol 2015; 73-74:9-19. [DOI: 10.1016/j.enzmictec.2015.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 01/21/2015] [Accepted: 03/01/2015] [Indexed: 10/23/2022]
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Classification of fungal and bacterial lytic polysaccharide monooxygenases. BMC Genomics 2015; 16:368. [PMID: 25956378 PMCID: PMC4424831 DOI: 10.1186/s12864-015-1601-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 04/29/2015] [Indexed: 11/21/2022] Open
Abstract
Background Lytic polysaccharide monooxygenases are important enzymes for the decomposition of recalcitrant biological macromolecules such as plant cell wall and chitin polymers. These enzymes were originally designated glycoside hydrolase family 61 and carbohydrate-binding module family 33 but are now classified as auxiliary activities 9, 10 and 11 in the CAZy database. To obtain a systematic analysis of the divergent families of lytic polysaccharide monooxygenases we used Peptide Pattern Recognition to divide 5396 protein sequences resembling enzymes from families AA9 (1828 proteins), AA10 (2799 proteins) and AA11 (769 proteins) into subfamilies. Results The results showed that the lytic polysaccharide monooxygenases have two conserved regions identified by conserved peptides specific for each AA family. The peptides were used for in silico PCR discovery of the lytic polysaccharide monooxygenases in 79 fungal and 95 bacterial genomes. The bacterial genomes encoded 0 – 7 AA10s (average 0.6). No AA9 or AA11 were found in the bacteria. The fungal genomes encoded 0 – 40 AA9s (average 7) and 0 – 15 AA11s (average 2) and two of the fungi possessed a gene encoding a putative AA10. The AA9s were mainly found in plant cell wall-degrading asco- and basidiomycetes in agreement with the described role of AA9 enzymes. In contrast, the AA11 proteins were found in 36 of the 39 ascomycetes and in only two of the 32 basidiomycetes and their abundance did not correlate to the degradation of cellulose and hemicellulose. Conclusions These results provides an overview of the sequence characteristics and occurrence of the divergent AA9, AA10 and AA11 families and pave the way for systematic investigations of the of lytic polysaccharide monooxygenases and for structure-function studies of these enzymes. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1601-6) contains supplementary material, which is available to authorized users.
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