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Engelberts JP, Robbins SJ, Herbold CW, Moeller FU, Jehmlich N, Laffy PW, Wagner M, Webster NS. Metabolic reconstruction of the near complete microbiome of the model sponge Ianthella basta. Environ Microbiol 2023; 25:646-660. [PMID: 36480164 PMCID: PMC10947273 DOI: 10.1111/1462-2920.16302] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022]
Abstract
Many marine sponges host highly diverse microbiomes that contribute to various aspects of host health. Although the putative function of individual groups of sponge symbionts has been increasingly described, the extreme diversity has generally precluded in-depth characterization of entire microbiomes, including identification of syntrophic partnerships. The Indo-Pacific sponge Ianthella basta is emerging as a model organism for symbiosis research, hosting only three dominant symbionts: a Thaumarchaeotum, a Gammaproteobacterium, and an Alphaproteobacterium and a range of other low abundance or transitory taxa. Here, we retrieved metagenome assembled genomes (MAGs) representing >90% of I. basta's microbial community, facilitating the metabolic reconstruction of the sponge's near complete microbiome. Through this analysis, we identified metabolic complementarity between microbes, including vitamin sharing, described the importance of low abundance symbionts, and characterized a novel microbe-host attachment mechanism in the Alphaproteobacterium. We further identified putative viral sequences, highlighting the role viruses can play in maintaining symbioses in I. basta through the horizontal transfer of eukaryotic-like proteins, and complemented this data with metaproteomics to identify active metabolic pathways in bacteria, archaea, and viruses. This data provide the framework to adopt I. basta as a model organism for studying host-microbe interactions and provide a basis for in-depth physiological experiments.
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Affiliation(s)
- Joan Pamela Engelberts
- Australian Centre for Ecogenomics, School of Chemistry and Molecular BiosciencesThe University of QueenslandBrisbaneQueenslandAustralia
| | - Steven J. Robbins
- Australian Centre for Ecogenomics, School of Chemistry and Molecular BiosciencesThe University of QueenslandBrisbaneQueenslandAustralia
| | - Craig W. Herbold
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
| | - Florian U. Moeller
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
| | - Nico Jehmlich
- Department of Molecular Systems BiologyHelmholtz‐Centre for Environmental Research – UFZLeipzigGermany
| | - Patrick W. Laffy
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
| | - Michael Wagner
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
- Center for Microbial Communities, Department of Chemistry and BioscienceAalborg UniversityAalborgDenmark
| | - Nicole S. Webster
- Australian Centre for Ecogenomics, School of Chemistry and Molecular BiosciencesThe University of QueenslandBrisbaneQueenslandAustralia
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
- Australian Antarctic DivisionKingstonTasmaniaAustralia
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Abdian PL, Malori MS, Caramelo JJ, Checchi AM, Russo DM, Zorreguieta A, Berretta MF, Benintende G. Fusion of a bacterial cadherin-like domain and green fluorescent protein as a specific probe to study biofilm matrix formation in Rhizobium spp. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36748557 DOI: 10.1099/mic.0.001284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Rhizobium adhering proteins or 'Raps' are secreted proteins identified in a very restricted group of rhizobial strains, specifically those belonging to R. leguminosarum and R. etli. The distinctive feature of members of the Rap family is the presence of one or two cadherin-like domains or CHDLs that are also present in numerous extracellular bacterial and archaeal proteins and were proposed to confer carbohydrate binding ability. We have previously made an in-depth characterization of RapA2, a calcium-binding lectin, composed by two CHDLs, involved in biofilm matrix remodelling in R. leguminosarum bv. viciae 3841. In this study, CHDLs derived from RapA2 were analysed in detail, finding significant structural and functional differences despite their considerable sequence similarity. Only the carboxy-terminal CHDL retained properties similar to those displayed by RapA2. Our findings were used to obtain a novel fluorescent probe to study biofilm matrix development by confocal laser scanning microscopy, and also to shed some light on the role of the ubiquitous CHDL domains in bacterial secreted proteins.
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Affiliation(s)
- Patricia L Abdian
- Instituto de Microbiología y Zoología Agrícola (IMyZA), G.V. al IABiMo, INTA-CONICET, Nicolás Repetto y de los Reseros s/n, 1686, Hurlingham, Buenos Aires, Argentina
| | - María Soledad Malori
- Fundación Instituto Leloir, IIBBA CONICET, Patricias Argentinas 435, 1405, Buenos Aires, Argentina
| | - Julio J Caramelo
- Fundación Instituto Leloir, IIBBA CONICET, Patricias Argentinas 435, 1405, Buenos Aires, Argentina
| | - Abi Maglio Checchi
- Instituto de Microbiología y Zoología Agrícola (IMyZA), G.V. al IABiMo, INTA-CONICET, Nicolás Repetto y de los Reseros s/n, 1686, Hurlingham, Buenos Aires, Argentina
| | - Daniela M Russo
- Fundación Instituto Leloir, IIBBA CONICET, Patricias Argentinas 435, 1405, Buenos Aires, Argentina
| | - Angeles Zorreguieta
- Fundación Instituto Leloir, IIBBA CONICET, Patricias Argentinas 435, 1405, Buenos Aires, Argentina
| | - Marcelo F Berretta
- Instituto de Microbiología y Zoología Agrícola (IMyZA), G.V. al IABiMo, INTA-CONICET, Nicolás Repetto y de los Reseros s/n, 1686, Hurlingham, Buenos Aires, Argentina
| | - Graciela Benintende
- Instituto de Microbiología y Zoología Agrícola (IMyZA), G.V. al IABiMo, INTA-CONICET, Nicolás Repetto y de los Reseros s/n, 1686, Hurlingham, Buenos Aires, Argentina
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3
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Liu Y, Jin X, Wu C, Zhu X, Liu M, Call DR, Zhao Z. Genome-Wide Identification and Functional Characterization of β-Agarases in Vibrio astriarenae Strain HN897. Front Microbiol 2020; 11:1404. [PMID: 32670245 PMCID: PMC7326809 DOI: 10.3389/fmicb.2020.01404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 05/29/2020] [Indexed: 01/06/2023] Open
Abstract
The genus Vibrio is a genetically and metabolically versatile group of heterotrophic bacteria that are important contributors to carbon cycling within marine and estuarine ecosystems. HN897, a Vibrio strain isolated from the coastal seawater of South China, was shown to be agarolytic and capable of catabolizing D-galactose. Herein, we used Illumina and PacBio sequencing to assemble the whole genome sequence for the strain HN897, which was comprised of two circular chromosomes (Vas1 and Vas2). Genome-wide phylogenetic analysis with 140 other Vibrio sequences firmly placed the strain HN897 into the Marisflavi clade, with Vibrio astriarenae strain C7 being the closest relative. Of all types of carbohydrate-active enzyme classes, glycoside hydrolases (GH) were the most common in the HN897 genome. These included eight GHs identified as putative β-agarases belonging to GH16 and GH50 families in equal proportions. Synteny analysis showed that GH16 and GH50 genes were tandemly arrayed on two different chromosomes consistent with gene duplication. Gene knockout and complementation studies and phenotypic assays confirmed that Vas1_1339, a GH16_16 subfamily gene, exhibits an agarolytic phenotype of the strain. Collectively, these findings explained the agar-decomposing of strain HN897, but also provided valuable resources to gain more detailed insights into the evolution and physiological capability of the strain HN897, which was a presumptive member of the species V. astriarenae.
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Affiliation(s)
- Yupeng Liu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Xingkun Jin
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Chao Wu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Xinyuan Zhu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Min Liu
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
| | - Douglas R Call
- Paul G Allen School for Global Animal Health, Washington State University, Pullman, WA, United States
| | - Zhe Zhao
- Department of Marine Biology, College of Oceanography, Hohai University, Nanjing, China
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Ellilä S, Bromann P, Nyyssönen M, Itävaara M, Koivula A, Paulin L, Kruus K. Cloning of novel bacterial xylanases from lignocellulose-enriched compost metagenomic libraries. AMB Express 2019; 9:124. [PMID: 31385056 PMCID: PMC6682842 DOI: 10.1186/s13568-019-0847-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 07/25/2019] [Indexed: 11/18/2022] Open
Abstract
Xylanases are in important class of industrial enzymes that are essential for the complete hydrolysis of lignocellulosic biomass into fermentable sugars. In the present study, we report the cloning of novel xylanases with interesting properties from compost metagenomics libraries. Controlled composting of lignocellulosic materials was used to enrich the microbial population in lignocellulolytic organisms. DNA extracted from the compost samples was used to construct metagenomics libraries, which were screened for xylanase activity. In total, 40 clones exhibiting xylanase activity were identified and the thermostability of the discovered xylanases was assayed directly from the library clones. Five genes, including one belonging to the more rare family GH8, were selected for subcloning and the enzymes were expressed in recombinant form in E. coli. Preliminary characterization of the metagenome-derived xylanases revealed interesting properties of the novel enzymes, such as high thermostability and specific activity, and differences in hydrolysis profiles. One enzyme was found to perform better than a standard Trichoderma reesei xylanase in the hydrolysis of lignocellulose at elevated temperatures.
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Sawant SS, Tran TK, Salunke BK, Kim BS. Potential of Saccharophagus degradans for production of polyhydroxyalkanoates using cellulose. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.03.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Enhanced Agarose and Xylan Degradation for Production of Polyhydroxyalkanoates by Co-Culture of Marine Bacterium, Saccharophagus degradans and Its Contaminant, Bacillus cereus. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7030225] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Kusaykin MI, Silchenko AS, Zakharenko AM, Zvyagintseva TN. Fucoidanases. Glycobiology 2015; 26:3-12. [PMID: 26347522 DOI: 10.1093/glycob/cwv072] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 08/18/2015] [Indexed: 11/13/2022] Open
Abstract
In recent years, the research of fucoidans has steadily increased. The interest in these substances is due to their various biological activities. Despite a wide range of biological activity and the lack of oral toxicity, fucoidans remain relatively unexploited as a source of medicines because of their heterogeneity. Enzymes that degrade polyanionic polysaccharides are widely used for establishing their structures and structure-activity relationships. Sometimes, to obtain preparations of polysaccharides with standard characteristics, for example, medicines and food supplements, enzymatic treatment can be also applied. Only a few sources of enzymes with fucoidanase activity have been described, and only a few studies regarding the isolation and characterization of fucoidanases have been performed. The data on the specificity of fucoidanases: the type of cleaved glycoside bond, the relation between catalytic activity and the degree of substrate sulfation are scarce. The review summarizes achievements in the research of fucoidanases, mechanisms of enzymatic degradation of fucoidans, as well as of structures of sulfated fucooligosaccharides obtained under the action of fucoidanases.
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Affiliation(s)
- Mikhail I Kusaykin
- G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Vladivostok, 159, Prospect 100-let, Vladivostoku 690022, Russia
| | - Artem S Silchenko
- G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Vladivostok, 159, Prospect 100-let, Vladivostoku 690022, Russia
| | - Alexander M Zakharenko
- G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Vladivostok, 159, Prospect 100-let, Vladivostoku 690022, Russia
| | - Tatyana N Zvyagintseva
- G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Vladivostok, 159, Prospect 100-let, Vladivostoku 690022, Russia
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Ben David Y, Dassa B, Borovok I, Lamed R, Koropatkin NM, Martens EC, White BA, Bernalier-Donadille A, Duncan SH, Flint HJ, Bayer EA, Moraïs S. Ruminococcal cellulosome systems from rumen to human. Environ Microbiol 2015; 17:3407-26. [PMID: 25845888 DOI: 10.1111/1462-2920.12868] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 03/24/2015] [Accepted: 03/31/2015] [Indexed: 01/19/2023]
Abstract
A cellulolytic fiber-degrading bacterium, Ruminococcus champanellensis, was isolated from human faecal samples, and its genome was recently sequenced. Bioinformatic analysis of the R. champanellensis genome revealed numerous cohesin and dockerin modules, the basic elements of the cellulosome, and manual sequencing of partially sequenced genomic segments revealed two large tandem scaffoldin-coding genes that form part of a gene cluster. Representative R. champanellensis dockerins were tested against putative cohesins, and the results revealed three different cohesin-dockerin binding profiles which implied two major types of cellulosome architectures: (i) an intricate cell-bound system and (ii) a simplistic cell-free system composed of a single cohesin-containing scaffoldin. The cell-bound system can adopt various enzymatic architectures, ranging from a single enzyme to a large enzymatic complex comprising up to 11 enzymes. The variety of cellulosomal components together with adaptor proteins may infer a very tight regulation of its components. The cellulosome system of the human gut bacterium R. champanellensis closely resembles that of the bovine rumen bacterium Ruminococcus flavefaciens. The two species contain orthologous gene clusters comprising fundamental components of cellulosome architecture. Since R. champanellensis is the only human colonic bacterium known to degrade crystalline cellulose, it may thus represent a keystone species in the human gut.
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Affiliation(s)
- Yonit Ben David
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
| | - Bareket Dassa
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
| | - Ilya Borovok
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Ramat Aviv, Israel
| | - Raphael Lamed
- Department of Molecular Microbiology and Biotechnology, Tel Aviv University, Ramat Aviv, Israel
| | - Nicole M Koropatkin
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Eric C Martens
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Bryan A White
- Department of Animal Sciences and Institute for Genomic Biology, University of Illinois, Urbana, IL, USA
| | | | - Sylvia H Duncan
- Microbiology Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, UK
| | - Harry J Flint
- Microbiology Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, UK
| | - Edward A Bayer
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
| | - Sarah Moraïs
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
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Abdian PL, Caramelo JJ, Ausmees N, Zorreguieta A. RapA2 is a calcium-binding lectin composed of two highly conserved cadherin-like domains that specifically recognize Rhizobium leguminosarum acidic exopolysaccharides. J Biol Chem 2012; 288:2893-904. [PMID: 23235153 DOI: 10.1074/jbc.m112.411769] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In silico analyses have revealed a conserved protein domain (CHDL) widely present in bacteria that has significant structural similarity to eukaryotic cadherins. A CHDL domain was shown to be present in RapA, a protein that is involved in autoaggregation of Rhizobium cells, biofilm formation, and adhesion to plant roots as shown by us and others. Structural similarity to cadherins suggested calcium-dependent oligomerization of CHDL domains as a mechanistic basis for RapA action. Here we show by circular dichroism spectroscopy, light scattering, isothermal titration calorimetry, and other methods that RapA2 from Rhizobium leguminosarum indeed exhibits a cadherin-like β-sheet conformation and that its proper folding and stability are dependent on the binding of one calcium ion per protein molecule. By further in silico analysis we also reveal that RapA2 consists of two CHDL domains and expand the range of CHDL-containing proteins in bacteria and archaea. However, light scattering assays at various concentrations of added calcium revealed that RapA2 formed neither homo-oligomers nor hetero-oligomers with RapB (a distinct CHDL protein), indicating that RapA2 does not mediate cellular interactions through a cadherin-like mechanism. Instead, we demonstrate that RapA2 interacts specifically with the acidic exopolysaccharides (EPSs) produced by R. leguminosarum in a calcium-dependent manner, sustaining a role of these proteins in the development of the biofilm matrix made of EPS. Because EPS binding by RapA2 can only be attributed to its two CHDL domains, we propose that RapA2 is a calcium-dependent lectin and that CHDL domains in various bacterial and archaeal proteins confer carbohydrate binding activity to these proteins.
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Affiliation(s)
- Patricia L Abdian
- Fundación Instituto Leloir, IIBBA Consejo Nacional de Investigaciones Científicas y Tecnológicas, Patricias Argentinas 435, C1405BWE Buenos Aires, Argentina
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Expression patterns reveal niche diversification in a marine microbial assemblage. ISME JOURNAL 2012; 7:281-98. [PMID: 22931830 DOI: 10.1038/ismej.2012.96] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Resolving the ecological niches of coexisting marine microbial taxa is challenging due to the high species richness of microbial communities and the apparent functional redundancy in bacterial genomes and metagenomes. Here, we generated over 11 million Illumina reads of protein-encoding transcripts collected from well-mixed southeastern US coastal waters to characterize gene expression patterns distinguishing the ecological roles of hundreds of microbial taxa sharing the same environment. The taxa with highest in situ growth rates (based on relative abundance of ribosomal protein transcripts) were typically not the greatest contributors to community transcription, suggesting strong top-down ecological control, and their diverse transcriptomes indicated roles as metabolic generalists. The taxa with low in situ growth rates typically had low diversity transcriptomes dominated by specialized metabolisms. By identifying protein-encoding genes with atypically high expression for their level of conservation, unique functional roles of community members emerged related to substrate use (such as complex carbohydrates, fatty acids, methanesulfonate, taurine, tartrate, ectoine), alternative energy-conservation strategies (proteorhodopsin, AAnP, V-type pyrophosphatases, sulfur oxidation, hydrogen oxidation) and mechanisms for negotiating a heterogeneous environment (flagellar motility, gliding motility, adhesion strategies). On average, the heterotrophic bacterioplankton dedicated 7% of their transcriptomes to obtaining energy by non-heterotrophic means. This deep sequencing of a coastal bacterioplankton transcriptome provides the most highly resolved view of bacterioplankton niche dimensions yet available, uncovering a spectrum of unrecognized ecological strategies.
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Fraiberg M, Borovok I, Weiner RM, Lamed R, Bayer EA. Bacterial cadherin domains as carbohydrate binding modules: determination of affinity constants to insoluble complex polysaccharides. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2012; 908:109-18. [PMID: 22843394 DOI: 10.1007/978-1-61779-956-3_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cadherin (CA) and cadherin-like (CADG) doublet domains from the complex polysaccharide-degrading marine bacterium, Saccharophagus degradans 2-40, demonstrated reversible calcium-dependent binding to different complex polysaccharides, which serve as growth substrates for the bacterium. Here we describe a procedure based on adsorption of CA and CADG doublet domains to different insoluble complex polysaccharides, followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) for visualizing and quantifying the distribution of cadherins between the bound and unbound fractions. Scatchard plots were employed to determine the kinetics of interactions of CA and CADG with several complex carbohydrates. On the basis of these binding studies, the CA and CADG doublet domains are proposed to form a new family of carbohydrate-binding module (CBM).
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Affiliation(s)
- Milana Fraiberg
- Department of Molecular Microbiology and Biotechnology, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv, Israel
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S-layer homology domain proteins Csac_0678 and Csac_2722 are implicated in plant polysaccharide deconstruction by the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus. Appl Environ Microbiol 2011; 78:768-77. [PMID: 22138994 DOI: 10.1128/aem.07031-11] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genus Caldicellulosiruptor contains extremely thermophilic bacteria that grow on plant polysaccharides. The genomes of Caldicellulosiruptor species reveal certain surface layer homology (SLH) domain proteins that have distinguishing features, pointing to a role in lignocellulose deconstruction. Two of these proteins in Caldicellulosiruptor saccharolyticus (Csac_0678 and Csac_2722) were examined from this perspective. In addition to three contiguous SLH domains, the Csac_0678 gene encodes a glycoside hydrolase family 5 (GH5) catalytic domain and a family 28 carbohydrate-binding module (CBM); orthologs to Csac_0678 could be identified in all genome-sequenced Caldicellulosiruptor species. Recombinant Csac_0678 was optimally active at 75°C and pH 5.0, exhibiting both endoglucanase and xylanase activities. SLH domain removal did not impact Csac_0678 GH activity, but deletion of the CBM28 domain eliminated binding to crystalline cellulose and rendered the enzyme inactive on this substrate. Csac_2722 is the largest open reading frame (ORF) in the C. saccharolyticus genome (predicted molecular mass of 286,516 kDa) and contains two putative sugar-binding domains, two Big4 domains (bacterial domains with an immunoglobulin [Ig]-like fold), and a cadherin-like (Cd) domain. Recombinant Csac_2722, lacking the SLH and Cd domains, bound to cellulose and had detectable carboxymethylcellulose (CMC) hydrolytic activity. Antibodies directed against Csac_0678 and Csac_2722 confirmed that these proteins bound to the C. saccharolyticus S-layer. Their cellular localization and functional biochemical properties indicate roles for Csac_0678 and Csac_2722 in recruitment and hydrolysis of complex polysaccharides and the deconstruction of lignocellulosic biomass. Furthermore, these results suggest that related SLH domain proteins in other Caldicellulosiruptor genomes may also be important contributors to plant biomass utilization.
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Hutcheson SW, Zhang H, Suvorov M. Carbohydrase systems of Saccharophagus degradans degrading marine complex polysaccharides. Mar Drugs 2011; 9:645-665. [PMID: 21731555 PMCID: PMC3124978 DOI: 10.3390/md9040645] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 04/01/2011] [Accepted: 04/13/2011] [Indexed: 11/16/2022] Open
Abstract
Saccharophagus degradans 2-40 is a γ-subgroup proteobacterium capable of using many of the complex polysaccharides found in the marine environment for growth. To utilize these complex polysaccharides, this bacterium produces a plethora of carbohydrases dedicated to the processing of a carbohydrate class. Aiding in the identification of the contributing genes and enzymes is the known genome sequence for this bacterium. This review catalogs the genes and enzymes of the S. degradans genome that are likely to function in the systems for the utilization of agar, alginate, α- and β-glucans, chitin, mannans, pectins, and xylans and discusses the cell biology and genetics of each system as it functions to transfer carbon back to the bacterium.
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Affiliation(s)
- Steven W. Hutcheson
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Haitao Zhang
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
- Zymetis, Inc., 387 Technology Drive, College Park, MD 20742, USA; E-Mails: (H.Z.); (M.S.)
| | - Maxim Suvorov
- Zymetis, Inc., 387 Technology Drive, College Park, MD 20742, USA; E-Mails: (H.Z.); (M.S.)
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