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Siriwardena A, Khanal M, Barras A, Bande O, Mena-Barragán T, Mellet CO, Garcia Fernández JM, Boukherroub R, Szunerits S. Unprecedented inhibition of glycosidase-catalyzed substrate hydrolysis by nanodiamond-grafted O-glycosides. RSC Adv 2015. [DOI: 10.1039/c5ra21390h] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Carbohydrate-coated nanodiamond particles with lectin recognition capabilities are not only stable towards the hydrolytic action of glycosidases, but also are endowed with the ability to inhibit them.
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Affiliation(s)
- Aloysius Siriwardena
- Laboratoire de Glycochimie des Antimicrobiennes et Bioresources
- FRE-CNRS 3517
- Université de Picardie Jules Verne
- 80039 Amiens
- France
| | - Manakamana Khanal
- Institute of Electronics
- Microelectronics and Nanotechnology (IEMN)
- UMR-CNRS 8520
- Lille1 University
- Avenue Poincaré-BP 60069
| | - Alexandre Barras
- Institute of Electronics
- Microelectronics and Nanotechnology (IEMN)
- UMR-CNRS 8520
- Lille1 University
- Avenue Poincaré-BP 60069
| | - Omprakash Bande
- Laboratoire de Glycochimie des Antimicrobiennes et Bioresources
- FRE-CNRS 3517
- Université de Picardie Jules Verne
- 80039 Amiens
- France
| | | | | | | | - Rabah Boukherroub
- Institute of Electronics
- Microelectronics and Nanotechnology (IEMN)
- UMR-CNRS 8520
- Lille1 University
- Avenue Poincaré-BP 60069
| | - Sabine Szunerits
- Institute of Electronics
- Microelectronics and Nanotechnology (IEMN)
- UMR-CNRS 8520
- Lille1 University
- Avenue Poincaré-BP 60069
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202
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Bringing functions together with fusion enzymes—from nature’s inventions to biotechnological applications. Appl Microbiol Biotechnol 2014; 99:1545-56. [DOI: 10.1007/s00253-014-6315-1] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 12/04/2014] [Accepted: 12/09/2014] [Indexed: 12/18/2022]
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203
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Hirano T, Sugiyama K, Sakaki Y, Hakamata W, Park SY, Nishio T. Structure-based analysis of domain function of chitin oligosaccharide deacetylase fromVibrio parahaemolyticus. FEBS Lett 2014; 589:145-51. [DOI: 10.1016/j.febslet.2014.11.039] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 11/15/2014] [Accepted: 11/21/2014] [Indexed: 10/24/2022]
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204
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N-Glycosylation of the archaellum filament is not important for archaella assembly and motility, although N-Glycosylation is essential for motility in Sulfolobus acidocaldarius. Biochimie 2014; 118:294-301. [PMID: 25447136 DOI: 10.1016/j.biochi.2014.10.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 10/17/2014] [Indexed: 12/29/2022]
Abstract
N-Glycosylation is one of the predominant posttranslational modifications, which is found in all three domains of life. N-Glycosylation has been shown to influence many biological aspects of proteins, like protein folding, stability or activity. In this study we demonstrate that the archaellum filament subunit FlaB of Sulfolobus acidocaldarius is N-glycosylated. Each of the six predicted N-Glycosylation sites within FlaB are modified with the attachment of an N-glycan. Although, it has been previously shown that N-Glycosylation is essential for motility in S. acidocaldarius, as defects in the N-Glycosylation process resulted in none or reduced motile cells, strains lacking one to all six N-Glycosylation sites within FlaB still remained motile. Deletion of the first five N-Glycosylation sites in FlaB did not significantly affect the motility, whereas removal of all six N-Glycosylation sites reduced motility by about 40%. Transmission electron microscopy analyses of non glycosylated and glycosylated archaellum filament revealed no structural change in length. Therefore N-Glycosylation does not appear to be important for the stability and assembly of the archaellum filament itself, but plays a role in other parts of the archaellum assembly.
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205
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von Schantz L, Håkansson M, Logan DT, Nordberg-Karlsson E, Ohlin M. Carbohydrate binding module recognition of xyloglucan defined by polar contacts with branching xyloses and CH-Π interactions. Proteins 2014; 82:3466-75. [PMID: 25302425 DOI: 10.1002/prot.24700] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Revised: 09/03/2014] [Accepted: 09/19/2014] [Indexed: 12/13/2022]
Abstract
Engineering of novel carbohydrate-binding proteins that can be utilized in various biochemical and biotechnical applications would benefit from a deeper understanding of the biochemical interactions that determine protein-carbohydrate specificity. In an effort to understand further the basis for specificity we present the crystal structure of the multi-specific carbohydrate-binding module (CBM) X-2 L110F bound to a branched oligomer of xyloglucan (XXXG). X-2 L110F is an engineered CBM that can recognize xyloglucan, xylans and β-glucans. The structural observations of the present study compared with previously reported structures of X-2 L110F in complex with linear oligomers, show that the π-surface of a phenylalanine, F110, allows for interactions with hydrogen atoms on both linear (xylopentaose and cellopentaose) and branched ligands (XXXG). Furthermore, X-2 L110F is shown to have a relatively flexible binding cleft, as illustrated in binding to XXXG. This branched ligand requires a set of reorientations of protein side chains Q72, N31, and R142, although these residues have previously been determined as important for binding to xylose oligomers by mediating polar contacts. The loss of these polar contacts is compensated for in binding to XXXG by polar interactions mediated by other protein residues, T74, R115, and Y149, which interact mainly with the branching xyloses of the xyloglucan oligomer. Taken together, the present study illustrates in structural detail how CH-π interactions can influence binding specificity and that flexibility is a key feature for the multi-specificity displayed by X-2 L110F, allowing for the accommodation of branched ligands.
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Affiliation(s)
- Laura von Schantz
- Department of Immunotechnology, Lund University, Medicon Village, SE-223 81 Lund, Sweden
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206
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Wang YS, Ko CH, Chang HT, Yang KJ, Chen YJ, Huang SJ, Fang PJ, Chang CF, Tzou DLM. ¹H, ¹³C and ¹⁵N backbone and side-chain resonance assignments of a family 36 carbohydrate binding module of xylanase from Paenibacillus campinasensis. BIOMOLECULAR NMR ASSIGNMENTS 2014; 8:303-306. [PMID: 23835623 DOI: 10.1007/s12104-013-9505-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 06/29/2013] [Indexed: 06/02/2023]
Abstract
Paenibacillus campinasensis BL11 isolated from black liquor secretes multiple glycoside hydrolases (GHs) against all kinds of polysaccharides. GH consists of a catalytic module and non-catalytic carbohydrate-binding modules (CBMs), in which CBMs append to the catalytic module, mediating specific interactions with insoluble carbohydrates to promote the hydrolysis efficiency of the cognate enzyme. Endo-β-1,4-xylanase (XylX) is one of the GHs reveals high enzymatic activity in a wide range of pH and thermal endurance, suitable for bioconversion and bio-refinement applications. In this work, we report the resonance assignments of a family 36 CBM (characterized as CBM36) derived from XylX. Our investigations will facilitate molecular structure determination and molecular dynamics analysis of CBMs.
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Affiliation(s)
- Yu-Sheng Wang
- School of Forestry and Resource Conservation, National Taiwan University, Taipei, Taiwan, ROC
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207
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208
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Xu C, Wang BC, Yu Z, Sun M. Structural insights into Bacillus thuringiensis Cry, Cyt and parasporin toxins. Toxins (Basel) 2014; 6:2732-70. [PMID: 25229189 PMCID: PMC4179158 DOI: 10.3390/toxins6092732] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 08/26/2014] [Accepted: 08/28/2014] [Indexed: 11/30/2022] Open
Abstract
Since the first X-ray structure of Cry3Aa was revealed in 1991, numerous structures of B. thuringiensis toxins have been determined and published. In recent years, functional studies on the mode of action and resistance mechanism have been proposed, which notably promoted the developments of biological insecticides and insect-resistant transgenic crops. With the exploration of known pore-forming toxins (PFTs) structures, similarities between PFTs and B. thuringiensis toxins have provided great insights into receptor binding interactions and conformational changes from water-soluble to membrane pore-forming state of B. thuringiensis toxins. This review mainly focuses on the latest discoveries of the toxin working mechanism, with the emphasis on structural related progress. Based on the structural features, B. thuringiensis Cry, Cyt and parasporin toxins could be divided into three categories: three-domain type α-PFTs, Cyt toxin type β-PFTs and aerolysin type β-PFTs. Structures from each group are elucidated and discussed in relation to the latest data, respectively.
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Affiliation(s)
- Chengchen Xu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Bi-Cheng Wang
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA.
| | - Ziniu Yu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
| | - Ming Sun
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
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209
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Blackman LM, Cullerne DP, Hardham AR. Bioinformatic characterisation of genes encoding cell wall degrading enzymes in the Phytophthora parasitica genome. BMC Genomics 2014; 15:785. [PMID: 25214042 PMCID: PMC4176579 DOI: 10.1186/1471-2164-15-785] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 09/03/2014] [Indexed: 12/13/2022] Open
Abstract
Background A critical aspect of plant infection by the majority of pathogens is penetration of the plant cell wall. This process requires the production and secretion of a broad spectrum of pathogen enzymes that target and degrade the many complex polysaccharides in the plant cell wall. As a necessary framework for a study of the expression of cell wall degrading enzymes (CWDEs) produced by the broad host range phytopathogen, Phytophthora parasitica, we have conducted an in-depth bioinformatics analysis of the entire complement of genes encoding CWDEs in this pathogen’s genome. Results Our bioinformatic analysis indicates that 431 (2%) of the 20,825 predicted proteins encoded by the P. parasitica genome, are carbohydrate-active enzymes (CAZymes) involved in the degradation of cell wall polysaccharides. Of the 431 proteins, 337 contain classical N-terminal secretion signals and 67 are predicted to be targeted to the non-classical secretion pathway. Identification of CAZyme catalytic activity based on primary protein sequence is difficult, nevertheless, detailed comparisons with previously characterized enzymes has allowed us to determine likely enzyme activities and targeted substrates for many of the P. parasitica CWDEs. Some proteins (12%) contain more than one CAZyme module but, in most cases, multiple modules are from the same CAZyme family. Only 12 P. parasitica CWDEs contain both catalytically-active (glycosyl hydrolase) and non-catalytic (carbohydrate binding) modules, a situation that contrasts with that in fungal phytopathogens. Other striking differences between the complements of CWDEs in P. parasitica and fungal phytopathogens are seen in the CAZyme families that target cellulose, pectins or β-1,3-glucans (e.g. callose). About 25% of P. parasitica CAZymes are solely directed towards pectin degradation, with the majority coming from pectin lyase or carbohydrate esterase families. Fungal phytopathogens typically contain less than half the numbers of these CAZymes. The P. parasitica genome, like that of other Oomycetes, is rich in CAZymes that target β-1,3-glucans. Conclusions This detailed analysis of the full complement of P. parasitica cell wall degrading enzymes provides a framework for an in-depth study of patterns of expression of these pathogen genes during plant infection and the induction or repression of expression by selected substrates. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-785) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Leila M Blackman
- Plant Science Division, Research School of Biology, College of Medicine, Biology and Environment, The Australian National University, Canberra ACT 0200, Australia.
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210
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Sainz-Polo MA, Valenzuela SV, González B, Pastor FIJ, Sanz-Aparicio J. Structural analysis of glucuronoxylan-specific Xyn30D and its attached CBM35 domain gives insights into the role of modularity in specificity. J Biol Chem 2014; 289:31088-101. [PMID: 25202007 DOI: 10.1074/jbc.m114.597732] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Glucuronoxylanase Xyn30D is a modular enzyme containing a family 30 glycoside hydrolase catalytic domain and an attached carbohydrate binding module of the CBM35 family. We present here the three-dimensional structure of the full-length Xyn30D at 2.4 Å resolution. The catalytic domain folds into an (α/β)8 barrel with an associated β-structure, whereas the attached CBM35 displays a jellyroll β-sandwich including two calcium ions. Although both domains fold in an independent manner, the linker region makes polar interactions with the catalytic domain, allowing a moderate flexibility. The ancillary Xyn30D-CBM35 domain has been expressed and crystallized, and its binding abilities have been investigated by soaking experiments. Only glucuronic acid-containing ligands produced complexes, and their structures have been solved. A calcium-dependent glucuronic acid binding site shows distinctive structural features as compared with other uronic acid-specific CBM35s, because the presence of two aromatic residues delineates a wider pocket. The nonconserved Glu(129) makes a bidentate link to calcium and defines region E, previously identified as specificity hot spot. The molecular surface of Xyn30D-CBM35 shows a unique stretch of negative charge distribution extending from its binding pocket that might indicate some oriented interaction with its target substrate. The binding ability of Xyn30D-CBM35 to different xylans was analyzed by affinity gel electrophoresis. Some binding was observed with rye glucuronoarabinoxylan in presence of calcium chelating EDTA, which would indicate that Xyn30D-CBM35 might establish interaction to other components of xylan, such as arabinose decorations of glucuronoarabinoxylan. A role in depolymerization of highly substituted chemically complex xylans is proposed.
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Affiliation(s)
- M Angela Sainz-Polo
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
| | - Susana Valeria Valenzuela
- the Departamento de Microbiología, Facultad de Biología. Universidad de Barcelona. 08028 Barcelona, Spain
| | - Beatriz González
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
| | - F I Javier Pastor
- the Departamento de Microbiología, Facultad de Biología. Universidad de Barcelona. 08028 Barcelona, Spain
| | - Julia Sanz-Aparicio
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
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211
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Campos BM, Alvarez TM, Liberato MV, Polikarpov I, Gilbert HJ, Zeri ACDM, Squina FM. Cloning, purification, crystallization and preliminary X-ray studies of a carbohydrate-binding module (CBM_E1) derived from sugarcane soil metagenome. Acta Crystallogr F Struct Biol Commun 2014; 70:1232-5. [PMID: 25195898 PMCID: PMC4157425 DOI: 10.1107/s2053230x14015520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 07/02/2014] [Indexed: 11/10/2022] Open
Abstract
In recent years, owing to the growing global demand for energy, dependence on fossil fuels, limited natural resources and environmental pollution, biofuels have attracted great interest as a source of renewable energy. However, the production of biofuels from plant biomass is still considered to be an expensive technology. In this context, the study of carbohydrate-binding modules (CBMs), which are involved in guiding the catalytic domains of glycoside hydrolases for polysaccharide degradation, is attracting growing attention. Aiming at the identification of new CBMs, a sugarcane soil metagenomic library was analyzed and an uncharacterized CBM (CBM_E1) was identified. In this study, CBM_E1 was expressed, purified and crystallized. X-ray diffraction data were collected to 1.95 Å resolution. The crystals, which were obtained by the sitting-drop vapour-diffusion method, belonged to space group I23, with unit-cell parameters a = b = c = 88.07 Å.
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Affiliation(s)
- Bruna Medeia Campos
- Laboratório Nacional de Biociências (LNBio), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, São Paulo, Brazil
| | - Thabata Maria Alvarez
- Laboratório Nacional de Ciências e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, São Paulo, Brazil
| | - Marcelo Vizona Liberato
- Laboratório Nacional de Ciências e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, São Paulo, Brazil
| | - Igor Polikarpov
- Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil
| | - Harry J. Gilbert
- Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne, England
| | - Ana Carolina de Mattos Zeri
- Laboratório Nacional de Biociências (LNBio), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, São Paulo, Brazil
| | - Fabio Marcio Squina
- Laboratório Nacional de Ciências e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, São Paulo, Brazil
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212
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Extracellular secretion of noncatalytic plant cell wall-binding proteins by the cellulolytic thermophile Caldicellulosiruptor bescii. J Bacteriol 2014; 196:3784-92. [PMID: 25157080 DOI: 10.1128/jb.01897-14] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Caldicellulosiruptor bescii efficiently degrades cellulose, xylan, and native grasses at high temperatures above 70°C under anaerobic conditions. C. bescii extracellularly secretes multidomain glycoside hydrolases along with proteins of unknown function. In this study, we analyzed the C. bescii proteins that bind to the cell walls of timothy grass by using mass spectrometry, and we identified four noncatalytic plant cell wall-binding proteins (PWBPs) with high pI values (9.2 to 9.6). A search of a conserved domain database showed that these proteins possess a common domain related to solute-binding proteins. In addition, 12 genes encoding PWBP-like proteins were detected in the C. bescii genomic sequence. To analyze the binding properties of PWBPs, recombinant PWBP57 and PWBP65, expressed in Escherichia coli, were prepared. The PWBPs displayed a wide range of binding specificities: they bound to cellulose, lichenan, xylan, arabinoxylan, glucuronoxylan, mannan, glucomannan, pectin, oligosaccharides, and the cell walls of timothy grass. The proteins showed the highest binding affinity for the plant cell wall, with association constant (Ka) values of 5.2 × 10(6) to 44 × 10(6) M(-1) among the insoluble polysaccharides tested, as measured using depletion binding isotherms. Affinity gel electrophoresis demonstrated that the proteins bound to the acidic polymer pectin most strongly among the soluble polysaccharides tested. Fluorescence microscopic analysis showed that the proteins bound preferentially to the cell wall in a section of grass leaf. Binding of noncatalytic PWBPs with high pI values might be necessary for efficient utilization of polysaccharides by C. bescii at high temperatures.
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213
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Munir RI, Schellenberg J, Henrissat B, Verbeke TJ, Sparling R, Levin DB. Comparative analysis of carbohydrate active enzymes in Clostridium termitidis CT1112 reveals complex carbohydrate degradation ability. PLoS One 2014; 9:e104260. [PMID: 25101643 PMCID: PMC4125193 DOI: 10.1371/journal.pone.0104260] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 07/11/2014] [Indexed: 02/06/2023] Open
Abstract
Clostridium termitidis strain CT1112 is an anaerobic, gram positive, mesophilic, cellulolytic bacillus isolated from the gut of the wood-feeding termite, Nasutitermes lujae. It produces biofuels such as hydrogen and ethanol from cellulose, cellobiose, xylan, xylose, glucose, and other sugars, and therefore could be used for biofuel production from biomass through consolidated bioprocessing. The first step in the production of biofuel from biomass by microorganisms is the hydrolysis of complex carbohydrates present in biomass. This is achieved through the presence of a repertoire of secreted or complexed carbohydrate active enzymes (CAZymes), sometimes organized in an extracellular organelle called cellulosome. To assess the ability and understand the mechanism of polysaccharide hydrolysis in C. termitidis, the recently sequenced strain CT1112 of C. termitidis was analyzed for both CAZymes and cellulosomal components, and compared to other cellulolytic bacteria. A total of 355 CAZyme sequences were identified in C. termitidis, significantly higher than other Clostridial species. Of these, high numbers of glycoside hydrolases (199) and carbohydrate binding modules (95) were identified. The presence of a variety of CAZymes involved with polysaccharide utilization/degradation ability suggests hydrolysis potential for a wide range of polysaccharides. In addition, dockerin-bearing enzymes, cohesion domains and a cellulosomal gene cluster were identified, indicating the presence of potential cellulosome assembly.
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Affiliation(s)
- Riffat I. Munir
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, Manitoba, Canada
| | - John Schellenberg
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | | | - Tobin J. Verbeke
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Richard Sparling
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - David B. Levin
- Department of Biosystems Engineering, University of Manitoba, Winnipeg, Manitoba, Canada
- * E-mail:
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214
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Carbohydrate-binding modules of fungal cellulases: occurrence in nature, function, and relevance in industrial biomass conversion. ADVANCES IN APPLIED MICROBIOLOGY 2014; 88:103-65. [PMID: 24767427 DOI: 10.1016/b978-0-12-800260-5.00004-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this review, the present knowledge on the occurrence of cellulases, with a special emphasis on the presence of carbohydrate-binding modules (CBMs) in various fungal strains, has been summarized. The importance of efficient fungal cellulases is growing due to their potential uses in biorefinery processes where lignocellulosic biomasses are converted to platform sugars and further to biofuels and chemicals. Most secreted cellulases studied in detail have a bimodular structure containing an active core domain attached to a CBM. CBMs are traditionally been considered as essential parts in cellulases, especially in cellobiohydrolases. However, presently available genome data indicate that many cellulases lack the binding domains in cellulose-degrading organisms. Recent data also demonstrate that CBMs are not necessary for the action of cellulases and they solely increase the concentration of enzymes on the substrate surfaces. On the other hand, in practical industrial processes where high substrate concentrations with low amounts of water are employed, the enzymes have been shown to act equally efficiently with and without CBM. Furthermore, available kinetic data show that enzymes without CBMs can desorb more readily from the often lignaceous substrates, that is, they are not stuck on the substrates and are thus available for new actions. In this review, the available data on the natural habitats of different wood-degrading organisms (with emphasis on the amount of water present during wood degradation) and occurrence of cellulose-binding domains in their genome have been assessed in order to identify evolutionary advantages for the development of CBM-less cellulases in nature.
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215
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Lunetta JM, Pappagianis D. Identification, molecular characterization, and expression analysis of a DOMON-like type 9 carbohydrate-binding module domain-containing protein of Coccidioides posadasii. Med Mycol 2014; 52:591-609. [PMID: 25023485 DOI: 10.1093/mmy/myu020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Previously, we investigated the effect of N-acetylglucosamine (GlcNAc) on Coccidioides posadasii chitinolytic enzymes during in vitro spherule-endospore (S/E) phase culture. During those studies, sodium dodecyl sulfatepolyacrylamide gel electrophoresis analysis of supernatants from S/E phase cultures grown in Converse medium with or without added GlcNAc revealed a ∼ 28-kDa band (CFP28), whose abundance was increased by GlcNAc in parallel with the chitinolytic enzymes. Mass spectrometry (MS) of the CFP28 band revealed peptides that matched an open reading frame found in the tentative consensus sequence, TC20325, retrieved from the Dana Farber Cancer Institute C. posadasii Gene Index Database. The TC20325 cDNA sequence was used to design internal primers based on MS peptides and a full-length cDNA was isolated using a combination of rapid amplification of cDNA ends and reverse transcription-polymerase chain reaction. The deduced amino acid sequence of the full-length cDNA consists of 231 amino acid residues with a 19 aa signal peptide. The mature protein has a calculated molecular mass of ∼ 24.5 kDa, a theoretical pI of 6.09, and consists of a single DOMON-like type 9 carbohydrate-binding module (CBM9-like-3) conserved domain. The protein shares the highest sequence similarity (≥57%) to hypothetical proteins from fungi within the Pezizomycotina subphylum of Ascomycota. Antiserum against a recombinant version of CFP28 recognized native CFP28 in S/E phase cells and culture supernatants. CFP28 mRNA and protein expression were detectable in S/E phase in Converse medium, but were increased in the presence of added GlcNAc. Purified native CFP28 reacted with pooled sera from patients with coccidioidomycosis.
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Affiliation(s)
- Jennine M Lunetta
- Department of Medical Microbiology and Immunology, School of Medicine, University of California, Davis, California, USA
| | - Demosthenes Pappagianis
- Department of Medical Microbiology and Immunology, School of Medicine, University of California, Davis, California, USA
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216
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Silver DM, Kötting O, Moorhead GBG. Phosphoglucan phosphatase function sheds light on starch degradation. TRENDS IN PLANT SCIENCE 2014; 19:471-8. [PMID: 24534096 DOI: 10.1016/j.tplants.2014.01.008] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/09/2014] [Accepted: 01/14/2014] [Indexed: 05/07/2023]
Abstract
Phosphoglucan phosphatases are novel enzymes that remove phosphates from complex carbohydrates. In plants, these proteins are vital components in the remobilization of leaf starch at night. Breakdown of starch is initiated through reversible glucan phosphorylation to disrupt the semi-crystalline starch structure at the granule surface. The phosphoglucan phosphatases starch excess 4 (SEX4) and like-SEX4 2 (LSF2) dephosphorylate glucans to provide access for amylases that release maltose and glucose from starch. Another phosphatase, LSF1, is a putative inactive scaffold protein that may act as regulator of starch degradative enzymes at the granule surface. Absence of these phosphatases disrupts starch breakdown, resulting in plants accumulating excess starch. Here, we describe recent advances in understanding the biochemical and structural properties of each of these starch phosphatases.
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Affiliation(s)
- Dylan M Silver
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Oliver Kötting
- Institute for Agricultural Sciences, ETH Zürich, Zürich, Switzerland
| | - Greg B G Moorhead
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada.
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217
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Karnaouri A, Topakas E, Antonopoulou I, Christakopoulos P. Genomic insights into the fungal lignocellulolytic system of Myceliophthora thermophila. Front Microbiol 2014; 5:281. [PMID: 24995002 PMCID: PMC4061905 DOI: 10.3389/fmicb.2014.00281] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 05/22/2014] [Indexed: 01/08/2023] Open
Abstract
The microbial conversion of solid cellulosic biomass to liquid biofuels may provide a renewable energy source for transportation fuels. Cellulolytic fungi represent a promising group of organisms, as they have evolved complex systems for adaptation to their natural habitat. The filamentous fungus Myceliophthora thermophila constitutes an exceptionally powerful cellulolytic microorganism that synthesizes a complete set of enzymes necessary for the breakdown of plant cell wall. The genome of this fungus has been recently sequenced and annotated, allowing systematic examination and identification of enzymes required for the degradation of lignocellulosic biomass. The genomic analysis revealed the existence of an expanded enzymatic repertoire including numerous cellulases, hemicellulases, and enzymes with auxiliary activities, covering the most of the recognized CAZy families. Most of them were predicted to possess a secretion signal and undergo through post-translational glycosylation modifications. These data offer a better understanding of activities embedded in fungal lignocellulose decomposition mechanisms and suggest that M. thermophila could be made usable as an industrial production host for cellulolytic and hemicellulolytic enzymes.
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Affiliation(s)
- Anthi Karnaouri
- Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of Athens Athens, Greece ; Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Evangelos Topakas
- Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of Athens Athens, Greece
| | - Io Antonopoulou
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
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218
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Peng C, Wang Y, Liu F, Ren Y, Zhou K, Lv J, Zheng M, Zhao S, Zhang L, Wang C, Jiang L, Zhang X, Guo X, Bao Y, Wan J. FLOURY ENDOSPERM6 encodes a CBM48 domain-containing protein involved in compound granule formation and starch synthesis in rice endosperm. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 77:917-30. [PMID: 24456533 DOI: 10.1111/tpj.12444] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 12/23/2013] [Accepted: 01/13/2014] [Indexed: 05/18/2023]
Abstract
Starch is the most widespread form of energy storage in the plant kingdom. Although many enzymes and related factors have been identified for starch biosynthesis, unknown players remain to be identified, given that it is a complicated and sophisticated process. The endosperm of rice (Oryza sativa) has been used for the study of starch synthesis. Here, we report the cloning and characterization of the FLOURY ENDOSPERM6 (FLO6) gene in rice. In the flo6 mutant, the starch content is decreased and the normal physicochemical features of starch are changed. Significantly, flo6 mutant endosperm cells show obvious defects in compound granule formation. Map-based cloning showed that FLO6 encodes a protein of unknown function. It harbors an N-terminal transit peptide that ensures its correct localization and functions in the plastid, and a C-terminal carbohydrate-binding module 48 (CBM48) domain that binds to starch. Furthermore, FLO6 can interact with isoamylase1 (ISA1) both in vitro and in vivo, whereas ISA1 does not bind to starch directly. We thus propose that FLO6 may act as a starch-binding protein involved in starch synthesis and compound granule formation through a direct interaction with ISA1 in developing rice seeds. Our data provide a novel insight into the role of proteins with the CBM48 domain in plant species.
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Affiliation(s)
- Cheng Peng
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
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219
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Gao S, You C, Renneckar S, Bao J, Zhang YHP. New insights into enzymatic hydrolysis of heterogeneous cellulose by using carbohydrate-binding module 3 containing GFP and carbohydrate-binding module 17 containing CFP. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:24. [PMID: 24552554 PMCID: PMC3943381 DOI: 10.1186/1754-6834-7-24] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 02/07/2014] [Indexed: 05/05/2023]
Abstract
BACKGROUND The in-depth understanding of the enzymatic hydrolysis of cellulose with heterogeneous morphology (that is, crystalline versus amorphous) may help develop better cellulase cocktail mixtures and biomass pretreatment, wherein cost-effective release of soluble sugars from solid cellulosic materials remains the largest obstacle to the economic viability of second generation biorefineries. RESULTS In addition to the previously developed non-hydrolytic fusion protein, GC3, containing a green fluorescent protein (GFP) and a family 3 carbohydrate-binding module (CBM3) that can bind both surfaces of amorphous and crystalline celluloses, we developed a new protein probe, CC17, which contained a mono-cherry fluorescent protein (CFP) and a family 17 carbohydrate-binding module (CBM17) that can bind only amorphous cellulose surfaces. Via these two probes, the surface accessibilities of amorphous and crystalline celluloses were determined quantitatively. Our results for the enzymatic hydrolysis of microcrystalline cellulose (Avicel) suggested that: 1) easily accessible amorphous cellulose on the surface of Avicel is preferentially hydrolyzed at the very early period of hydrolysis (that is, several minutes with a cellulose conversion of 2.8%); 2) further hydrolysis of Avicel is a typical layer-by-layer mechanism, that is, amorphous and crystalline cellulose regions were hydrolyzed simultaneously; and 3) most amorphous cellulose within the interior of the Avicel particles cannot be accessed by cellulase. CONCLUSIONS The crystallinity index (CrI), reflecting a mass-average (three-dimensional) cellulose characteristic, did not represent the key substrate surface (two-dimensional) characteristic related to enzymatic hydrolysis.
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Affiliation(s)
- Shuhong Gao
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
- Biological Systems Engineering Department, Virginia Tech, 304-A Seitz Hall, Blacksburg, VA 24061, USA
| | - Chun You
- Biological Systems Engineering Department, Virginia Tech, 304-A Seitz Hall, Blacksburg, VA 24061, USA
| | - Scott Renneckar
- Sustainable Biomaterials Department, Virginia Tech, 230 Cheatham Hall, Blacksburg, VA 24061, USA
| | - Jie Bao
- School of Biotechnology, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yi-Heng Percival Zhang
- Biological Systems Engineering Department, Virginia Tech, 304-A Seitz Hall, Blacksburg, VA 24061, USA
- Cell-Free Bioinnovations Inc., 2200 Kraft Drive, Suite 1200B, Blacksburg, VA 24060, USA
- Gate Fuels Inc., Blacksburg, VA 24060, USA
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220
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Liu K, Zhang W, Lai Y, Xiang M, Wang X, Zhang X, Liu X. Drechslerella stenobrocha genome illustrates the mechanism of constricting rings and the origin of nematode predation in fungi. BMC Genomics 2014; 15:114. [PMID: 24507587 PMCID: PMC3924618 DOI: 10.1186/1471-2164-15-114] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 02/04/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Nematode-trapping fungi are a unique group of organisms that can capture nematodes using sophisticated trapping structures. The genome of Drechslerella stenobrocha, a constricting-ring-forming fungus, has been sequenced and reported, and provided new insights into the evolutionary origins of nematode predation in fungi, the trapping mechanisms, and the dual lifestyles of saprophagy and predation. RESULTS The genome of the fungus Drechslerella stenobrocha, which mechanically traps nematodes using a constricting ring, was sequenced. The genome was 29.02 Mb in size and was found rare instances of transposons and repeat induced point mutations, than that of Arthrobotrys oligospora. The functional proteins involved in nematode-infection, such as chitinases, subtilisins, and adhesive proteins, underwent a significant expansion in the A. oligospora genome, while there were fewer lectin genes that mediate fungus-nematode recognition in the D. stenobrocha genome. The carbohydrate-degrading enzyme catalogs in both species were similar to those of efficient cellulolytic fungi, suggesting a saprophytic origin of nematode-trapping fungi. In D. stenobrocha, the down-regulation of saprophytic enzyme genes and the up-regulation of infection-related genes during the capture of nematodes indicated a transition between dual life strategies of saprophagy and predation. The transcriptional profiles also indicated that trap formation was related to the protein kinase C (PKC) signal pathway and regulated by Zn(2)-C6 type transcription factors. CONCLUSIONS The genome of D. stenobrocha provides support for the hypothesis that nematode trapping fungi evolved from saprophytic fungi in a high carbon and low nitrogen environment. It reveals the transition between saprophagy and predation of these fungi and also proves new insights into the mechanisms of mechanical trapping.
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Affiliation(s)
| | | | | | | | | | | | - Xingzhong Liu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, No 3 1st Beichen West Rd,, Chaoyang District, Beijing 100101, China.
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221
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Ratnadewi AAI, Fanani M, Kurniasih SD, Sakka M, Wasito EB, Sakka K, Nurachman Z, Puspaningsih NNT. β-D-xylosidase from Geobacillus thermoleovorans IT-08: biochemical characterization and bioinformatics of the enzyme. Appl Biochem Biotechnol 2013; 170:1950-64. [PMID: 23797510 DOI: 10.1007/s12010-013-0329-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 06/11/2013] [Indexed: 11/24/2022]
Abstract
The gene encoding a thermostable β-D-xylosidase (GbtXyl43B) from Geobacillus thermoleovorans IT-08 was cloned in pET30a and expressed in Escherichia coli; additionally, characterization and kinetic analysis of GbtXyl43B were carried out. The gene product was purified to apparent homogeneity showing M r of 72 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The enzyme exhibited an optimum temperature and pH of 60 °C and 6.0, respectively. In terms of stability, GbtXyl43B was stable at 60 °C at pH 6.0 for 1 h as well as at pH 6-8 at 4 °C for 24 h. The enzyme had a catalytic efficiency (k cat/K M) of 0.0048 ± 0.0010 s(-1) mM(-1) on p-nitrophenyl-β-D-xylopyranoside substrate. Thin layer chromatography product analysis indicated that GbtXyl43B was exoglycosidase cleaving single xylose units from the nonreducing end of xylan. The activity of GbtXyl43B on insoluble xylan was eightfold higher than on soluble xylan. Bioinformatics analysis showed that GbtXyl43B belonging to glycoside hydrolase family 43 contained carbohydrate-binding module (CBM; residues 15 to 149 forming eight antiparallel β-strands) and catalytic module (residues 157 to 604 forming five-bladed β-propeller fold with predicted catalytic residues to be Asp287 and Glu476). CBM of GbtXyl43B dominated by the Phe residues which grip the carbohydrate is proposed as a novel CBM36 subfamily.
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Affiliation(s)
- Anak Agung Istri Ratnadewi
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Jember, Jalan Kalimantan 37, Jember, 68121, Indonesia
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222
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Rísquez‐Cuadro R, García Fernández JM, Nierengarten J, Ortiz Mellet C. Fullerene‐sp
2
‐Iminosugar Balls as Multimodal Ligands for Lectins and Glycosidases: A Mechanistic Hypothesis for the Inhibitory Multivalent Effect. Chemistry 2013; 19:16791-803. [DOI: 10.1002/chem.201303158] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Indexed: 01/25/2023]
Affiliation(s)
- Rocío Rísquez‐Cuadro
- Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, C/Prof. García González 1, 41012 Sevilla (Spain)
| | - José M. García Fernández
- Instituto de Investigaciones Químicas (IIQ), CSIC ‐ Universidad de Sevilla, Av. Américo Vespucio 49, Isla de la Cartuja, 41092 Sevilla (Spain)
| | - Jean‐François Nierengarten
- Laboratoire de Chimie des Matériaux Moléculaires, Université de Strasbourg et CNRS (UMR 7509), Ecole Européenne de Chimie, Polymères et Matériaux, 25 rue Becquerel, 67087 Strasbourg (France)
| | - Carmen Ortiz Mellet
- Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, C/Prof. García González 1, 41012 Sevilla (Spain)
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223
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Chagnot C, Zorgani MA, Astruc T, Desvaux M. Proteinaceous determinants of surface colonization in bacteria: bacterial adhesion and biofilm formation from a protein secretion perspective. Front Microbiol 2013; 4:303. [PMID: 24133488 PMCID: PMC3796261 DOI: 10.3389/fmicb.2013.00303] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 09/22/2013] [Indexed: 01/30/2023] Open
Abstract
Bacterial colonization of biotic or abiotic surfaces results from two quite distinct physiological processes, namely bacterial adhesion and biofilm formation. Broadly speaking, a biofilm is defined as the sessile development of microbial cells. Biofilm formation arises following bacterial adhesion but not all single bacterial cells adhering reversibly or irreversibly engage inexorably into a sessile mode of growth. Among molecular determinants promoting bacterial colonization, surface proteins are the most functionally diverse active components. To be present on the bacterial cell surface, though, a protein must be secreted in the first place. Considering the close association of secreted proteins with their cognate secretion systems, the secretome (which refers both to the secretion systems and their protein substrates) is a key concept to apprehend the protein secretion and related physiological functions. The protein secretion systems are here considered in light of the differences in the cell-envelope architecture between diderm-LPS (archetypal Gram-negative), monoderm (archetypal Gram-positive) and diderm-mycolate (archetypal acid-fast) bacteria. Besides, their cognate secreted proteins engaged in the bacterial colonization process are regarded from single protein to supramolecular protein structure as well as the non-classical protein secretion. This state-of-the-art on the complement of the secretome (the secretion systems and their cognate effectors) involved in the surface colonization process in diderm-LPS and monoderm bacteria paves the way for future research directions in the field.
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Affiliation(s)
- Caroline Chagnot
- UR454 Microbiologie, INRA Saint-Genès Champanelle, France ; UR370 Qualité des Produits Animaux, INRA Saint-Genès Champanelle, France
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224
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Adrangi S, Faramarzi MA. From bacteria to human: a journey into the world of chitinases. Biotechnol Adv 2013; 31:1786-95. [PMID: 24095741 DOI: 10.1016/j.biotechadv.2013.09.012] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 09/26/2013] [Accepted: 09/28/2013] [Indexed: 12/28/2022]
Abstract
Chitinases, the enzymes responsible for the biological degradation of chitin, are found in a wide range of organisms from bacteria to higher plants and animals. They participate in numerous physiological processes such as nutrition, parasitism, morphogenesis and immunity. Many organisms, in addition to chitinases, produce inactive chitinase-like lectins that despite lacking enzymatic activity are involved in several regulatory functions. Most known chitinases belong to families 18 and 19 of glycosyl hydrolases, however a few chitinases that belong to families 23 and 48 have also been identified in recent years. In this review, different aspects of chitinases and chi-lectins from bacteria, fungi, insects, plants and mammals are discussed.
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Affiliation(s)
- Sina Adrangi
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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225
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Kumagai Y, Kawakami K, Uraji M, Hatanaka T. Effect of the binding of bivalent ion to the calcium-binding site responsible for the thermal stability of actinomycete mannanase: Potential use in production of functional mannooligosaccharides. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.molcatb.2013.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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226
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De La Mare M, Guais O, Bonnin E, Weber J, Francois JM. Molecular and biochemical characterization of three GH62 α-l-arabinofuranosidases from the soil deuteromycete Penicillium funiculosum. Enzyme Microb Technol 2013; 53:351-8. [DOI: 10.1016/j.enzmictec.2013.07.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 07/29/2013] [Accepted: 07/31/2013] [Indexed: 01/17/2023]
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227
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Khan MIM, Sajjad M, Sadaf S, Zafar R, Niazi UHK, Akhtar MW. The nature of the carbohydrate binding module determines the catalytic efficiency of xylanase Z of Clostridium thermocellum. J Biotechnol 2013; 168:403-8. [PMID: 24095983 DOI: 10.1016/j.jbiotec.2013.09.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 08/22/2013] [Accepted: 09/12/2013] [Indexed: 11/30/2022]
Abstract
Xylanase Z of Clostridium thermocellum exists as a complex in the cellulosome with N-terminus feruloyl esterase, a carbohydrate binding module (CBM6) and a dockerin domain. To study the role of the binding modules on the activity of XynZ, different variants with the CBM6 attached to the catalytic domain at its C-terminal (XynZ-CB) and N-terminal (XynZ-BC), and the CBM22 attached at N-terminus (XynZ-B'C) were expressed in Escherichia coli at levels around 30% of the total cell proteins. The activities of XynZ-BC, XynZ-CB and XynZ-B'C were 4200, 4180 and 20,700U μM(-1) against birchwood xylan, respectively. Substrate binding studies showed that in case of XynZ-BC and XynZ-CB the substrate birchwood xylan remaining unbound were 51 and 52%, respectively, whereas in the case of XynZ-B'C the substrate remaining unbound was 39% under the assay conditions used. The molecular docking studies showed that the binding site of CBM22 in XynZ-B'C is more exposed and thus available for substrate binding as compared to the tunnel shape binding pocket produced in XynZ-BC and thus hindering the substrate binding. The substrate binding data for the two constructs are in agreement with this explanation.
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228
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Engineering chimeric thermostable GH7 cellobiohydrolases in Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2013; 98:2991-3001. [DOI: 10.1007/s00253-013-5177-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 07/29/2013] [Accepted: 07/30/2013] [Indexed: 10/26/2022]
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229
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Lu H, Luo H, Shi P, Huang H, Meng K, Yang P, Yao B. A novel thermophilic endo-β-1,4-mannanase from Aspergillus nidulans XZ3: functional roles of carbohydrate-binding module and Thr/Ser-rich linker region. Appl Microbiol Biotechnol 2013; 98:2155-63. [DOI: 10.1007/s00253-013-5112-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 07/08/2013] [Accepted: 07/09/2013] [Indexed: 10/26/2022]
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230
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Lam KL, Chi-Keung Cheung P. Non-digestible long chain beta-glucans as novel prebiotics. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.bcdf.2013.09.001] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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231
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Riley LM, Weadge JT, Baker P, Robinson H, Codée JDC, Tipton PA, Ohman DE, Howell PL. Structural and functional characterization of Pseudomonas aeruginosa AlgX: role of AlgX in alginate acetylation. J Biol Chem 2013; 288:22299-314. [PMID: 23779107 DOI: 10.1074/jbc.m113.484931] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The exopolysaccharide alginate, produced by mucoid Pseudomonas aeruginosa in the lungs of cystic fibrosis patients, undergoes two different chemical modifications as it is synthesized that alter the properties of the polymer and hence the biofilm. One modification, acetylation, causes the cells in the biofilm to adhere better to lung epithelium, form microcolonies, and resist the effects of the host immune system and/or antibiotics. Alginate biosynthesis requires 12 proteins encoded by the algD operon, including AlgX, and although this protein is essential for polymer production, its exact role is unknown. In this study, we present the X-ray crystal structure of AlgX at 2.15 Å resolution. The structure reveals that AlgX is a two-domain protein, with an N-terminal domain with structural homology to members of the SGNH hydrolase superfamily and a C-terminal carbohydrate-binding module. A number of residues in the carbohydrate-binding module form a substrate recognition "pinch point" that we propose aids in alginate binding and orientation. Although the topology of the N-terminal domain deviates from canonical SGNH hydrolases, the residues that constitute the Ser-His-Asp catalytic triad characteristic of this family are structurally conserved. In vivo studies reveal that site-specific mutation of these residues results in non-acetylated alginate. This catalytic triad is also required for acetylesterase activity in vitro. Our data suggest that not only does AlgX protect the polymer as it passages through the periplasm but that it also plays a role in alginate acetylation. Our results provide the first structural insight for a wide group of closely related bacterial polysaccharide acetyltransferases.
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Affiliation(s)
- Laura M Riley
- Program in Molecular Structure and Function, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
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232
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Fusing a carbohydrate-binding module into the Aspergillus usamii β-mannanase to improve its thermostability and cellulose-binding capacity by in silico design. PLoS One 2013; 8:e64766. [PMID: 23741390 PMCID: PMC3669383 DOI: 10.1371/journal.pone.0064766] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 04/18/2013] [Indexed: 11/25/2022] Open
Abstract
The AuMan5A, an acidophilic glycoside hydrolase (GH) family 5 β-mannanase derived from Aspergillus usamii YL-01-78, consists of an only catalytic domain (CD). To perfect enzymatic properties of the AuMan5A, a family 1 carbohydrate-binding module (CBM) of the Trichoderma reesei cellobiohydrolase I (TrCBH I), having the lowest binding free energy with cellobiose, was selected by in silico design, and fused into its C-terminus forming a fusion β-mannanase, designated as AuMan5A-CBM. Then, its encoding gene, Auman5A-cbm, was constructed as it was designed theoretically, and expressed in Pichia pastoris GS115. SDS-PAGE analysis displayed that both recombinant AuMan5A-CBM (reAuMan5A-CBM) and AuMan5A (reAuMan5A) were secreted into the cultured media with apparent molecular masses of 57.3 and 49.8 kDa, respectively. The temperature optimum of the reAuMan5A-CBM was 75°C, being 5°C higher than that of the reAuMan5A. They were stable at temperatures of 68 and 60°C, respectively. Compared with reAuMan5A, the reAuMan5A-CBM showed an obvious decrease in Km and a slight alteration in Vmax. In addition, the fusion of a CBM of the TrCBH I into the AuMan5A contributed to its cellulose-binding capacity.
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233
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Ribitsch D, Yebra AO, Zitzenbacher S, Wu J, Nowitsch S, Steinkellner G, Greimel K, Doliska A, Oberdorfer G, Gruber CC, Gruber K, Schwab H, Stana-Kleinschek K, Acero EH, Guebitz GM. Fusion of Binding Domains to Thermobifida cellulosilytica Cutinase to Tune Sorption Characteristics and Enhancing PET Hydrolysis. Biomacromolecules 2013; 14:1769-76. [DOI: 10.1021/bm400140u] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Doris Ribitsch
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Antonio Orcal Yebra
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Sabine Zitzenbacher
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Jing Wu
- State Key Laboratory of
Food Science and Technology, Jiangnan University, 1800 Lihu Ave., Wuxi, Jiangsu 214122, China
- School of Biotechnology
and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Ave.,
Wuxi, Jiangsu 214122, China
| | - Susanne Nowitsch
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Georg Steinkellner
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Katrin Greimel
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Ales Doliska
- Institute for Characterisation
and Processing of Polymers, University of Maribor, Smetanova ulica 17, 2000, Maribor, Slovenia
| | - Gustav Oberdorfer
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
- Department of Biochemistry, University of Washington, 3946 West
Stevens, Seattle, United States
| | - Christian C. Gruber
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Karl Gruber
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
- Institute of Molecular
Biosciencies, University of Graz, Humboldtstrasse 50/3, 8010, Graz, Austria
| | - Helmut Schwab
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
- Institute of Molecular
Biotechnology, Graz University of Technology, Petersgasse 14, 8010, Graz, Austria
| | - Karin Stana-Kleinschek
- Institute for Characterisation
and Processing of Polymers, University of Maribor, Smetanova ulica 17, 2000, Maribor, Slovenia
| | - Enrique Herrero Acero
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
| | - Georg M. Guebitz
- Enzymes and Polymers, Austrian Centre of Industrial Biotechnology ACIB, Petergasse
14, 8010, Graz, Austria
- Institute of Environmental
Biotechnology, University of Natural Resources and Life Sciences, Vienna, Konrad Lorenz Strasse 20,
3430 Tulln, Austria
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234
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Cucurachi M, Busconi M, Marudelli M, Soffritti G, Fogher C. Direct amplification of new cellulase genes from woodland soil purified DNA. Mol Biol Rep 2013; 40:4317-25. [PMID: 23645028 DOI: 10.1007/s11033-013-2519-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 04/27/2013] [Indexed: 12/12/2022]
Abstract
Eight genes encoding cellulolytic enzymes were obtained by direct PCR amplification of genomic DNA recovered from woodland soil samples. The direct amplifications were carried out by using primers designed from available online cellulase nucleotide sequences. The isolated genes were all different from each other and homologous to endo-β-1,4-glucanases of Bacillus subtilis. The cellulases were functionally expressed in Escherichia coli and tested on soluble substrate at 37 and 60 °C, showing different cellulolytic activities. Among these, the enzyme renamed CelWS6 exhibited good activity at higher temperatures. Further analysis of CelWS6 showed a high performance in acid environments (between pH 4.0 and 6.0) and at elevated temperatures with its maximum activity at pH 5.0 and 50 °C. At the optimum pH, it was very stable since more than 80 % of its original activity was maintained after an incubation of 120 min at 60 °C. Because the cellulases had different cellulolytic activities, but similar amino acid sequences, it was possible to assess the relationship between sequence and protein function.
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Affiliation(s)
- Marco Cucurachi
- Plantechno s.r.l, via Staffolo 60, 26041, Vicomoscano, Cremona, Italy
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235
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Maurelli L, Ionata E, La Cara F, Morana A. Chestnut shell as unexploited source of fermentable sugars: effect of different pretreatment methods on enzymatic saccharification. Appl Biochem Biotechnol 2013; 170:1104-18. [PMID: 23640265 DOI: 10.1007/s12010-013-0264-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 04/23/2013] [Indexed: 12/01/2022]
Abstract
Chestnut shell (CS) is an agronomic residue mainly used for extraction of antioxidants or as adsorbent of metal ions. It also contains some polysaccharide that has not been considered as potential source of fermentable sugars for biofuel production until now. In this study, the effect of different pretreatment methods on CS was evaluated in order to obtain the greatest conversion of cellulose and xylan into fermentable sugars. Hot acid impregnation, steam explosion (acid-catalysed or not), and aqueous ammonia soaking (AAS) were selected as pretreatments. The pretreated biomass was subjected to saccharification with two enzyme cocktails prepared from commercial preparations, and evaluation of the best pretreatment and enzyme cocktail was based on the yield of fermentable sugars produced. As AAS provided the best result after preliminary experiments, enhancement of sugar production was attempted by changing the concentrations of ammonium hydroxide, enzymes, and CS. The optimal pretreatment condition was 10 % ammonium hydroxide, 70 °C, 22 h with CS at 5 % solid loading. After saccharification of the pretreated CS for 72 h at 50 °C and pH 5.0 with a cocktail containing cellulase (Accellerase 1500), beta-glucosidase (Accellerase BG), and xylanase (Accellerase XY), glucose and xylose yields were 67.8 and 92.7 %, respectively.
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Affiliation(s)
- Luisa Maurelli
- Institute of Protein Biochemistry, National Research Council of Italy, Via Pietro Castellino 111, 80131 Naples, Italy.
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236
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Frederiksen RF, Paspaliari DK, Larsen T, Storgaard BG, Larsen MH, Ingmer H, Palcic MM, Leisner JJ. Bacterial chitinases and chitin-binding proteins as virulence factors. MICROBIOLOGY (READING, ENGLAND) 2013; 159:833-847. [PMID: 23519157 DOI: 10.1099/mic.0.051839-0] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Bacterial chitinases (EC 3.2.1.14) and chitin-binding proteins (CBPs) play a fundamental role in the degradation of the ubiquitous biopolymer chitin, and the degradation products serve as an important nutrient source for marine- and soil-dwelling bacteria. However, it has recently become clear that representatives of both Gram-positive and Gram-negative bacterial pathogens encode chitinases and CBPs that support infection of non-chitinous mammalian hosts. This review addresses this biological role of bacterial chitinases and CBPs in terms of substrate specificities, regulation, secretion and involvement in cellular and animal infection.
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Affiliation(s)
- Rikki F Frederiksen
- Department of Veterinary Disease Biology, Faculty of Health Sciences, University of Copenhagen, Grønnegaardsvej 15, 1870 Frederiksberg C., Denmark
| | - Dafni K Paspaliari
- Department of Veterinary Disease Biology, Faculty of Health Sciences, University of Copenhagen, Grønnegaardsvej 15, 1870 Frederiksberg C., Denmark
| | - Tanja Larsen
- Department of Veterinary Disease Biology, Faculty of Health Sciences, University of Copenhagen, Grønnegaardsvej 15, 1870 Frederiksberg C., Denmark
| | - Birgit G Storgaard
- Carlsberg Laboratory, Gamle Carlsbergvej 10, 1799 Copenhagen V., Denmark
- Department of Veterinary Disease Biology, Faculty of Health Sciences, University of Copenhagen, Grønnegaardsvej 15, 1870 Frederiksberg C., Denmark
| | - Marianne H Larsen
- Department of Veterinary Disease Biology, Faculty of Health Sciences, University of Copenhagen, Grønnegaardsvej 15, 1870 Frederiksberg C., Denmark
| | - Hanne Ingmer
- Department of Veterinary Disease Biology, Faculty of Health Sciences, University of Copenhagen, Grønnegaardsvej 15, 1870 Frederiksberg C., Denmark
| | - Monica M Palcic
- Carlsberg Laboratory, Gamle Carlsbergvej 10, 1799 Copenhagen V., Denmark
| | - Jørgen J Leisner
- Department of Veterinary Disease Biology, Faculty of Health Sciences, University of Copenhagen, Grønnegaardsvej 15, 1870 Frederiksberg C., Denmark
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237
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Manjeet K, Purushotham P, Neeraja C, Podile AR. Bacterial chitin binding proteins show differential substrate binding and synergy with chitinases. Microbiol Res 2013; 168:461-8. [PMID: 23480960 DOI: 10.1016/j.micres.2013.01.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 12/22/2012] [Accepted: 01/17/2013] [Indexed: 11/25/2022]
Abstract
Glycosyl hydrolase (GH) family 18 chitinases (Chi) and family 33 chitin binding proteins (CBPs) from Bacillus thuringiensis serovar kurstaki (BtChi and BtCBP), B. licheniformis DSM13 (BliChi and BliCBP) and Serratia proteamaculans 568 (SpChiB and SpCBP21) were used to study the efficiency and synergistic action of BtChi, BliChi and SpChiB individually with BtCBP, BliCBP or SpCBP21. Chitinase assay revealed that only BtChi and SpChiB showed synergism in hydrolysis of chitin, while there was no increase in products generated by BliChi, in the presence of the three above mentioned CBPs. This suggests that some (specific) CBPs are able to exert a synergistic effect on (specific) chitinases. A mutant of BliChi, designated as BliGH, was constructed by deleting the C-terminal fibronectin III (FnIII) and carbohydrate binding module 5 (CBM5) to assess the contribution of FnIII and CBM5 domains in the synergistic interactions of GH18 chitinases with CBPs. Chitinase assay with BliGH revealed that the accessory domains play a major role in making BliChi an efficient enzyme. We studied binding of BtCBP and BliCBP to α- and β-chitin. The BtCBP, BliCBP or SpCBP21 did not act synergistically with chitinases in hydrolysis of the chitin, interspersed with other polymers, present in fungal cell walls.
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Affiliation(s)
- Kaur Manjeet
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Andhra Pradesh, India
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238
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Bodelón G, Palomino C, Fernández LÁ. Immunoglobulin domains inEscherichia coliand other enterobacteria: from pathogenesis to applications in antibody technologies. FEMS Microbiol Rev 2013; 37:204-50. [DOI: 10.1111/j.1574-6976.2012.00347.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 06/07/2012] [Accepted: 06/14/2012] [Indexed: 11/28/2022] Open
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239
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Jensen SL, Larsen FH, Bandsholm O, Blennow A. Stabilization of semi-solid-state starch by branching enzyme-assisted chain-transfer catalysis at extreme substrate concentration. Biochem Eng J 2013. [DOI: 10.1016/j.bej.2012.12.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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240
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Chen S, Kaufman MG, Miazgowicz KL, Bagdasarian M, Walker ED. Molecular characterization of a cold-active recombinant xylanase from Flavobacterium johnsoniae and its applicability in xylan hydrolysis. BIORESOURCE TECHNOLOGY 2013; 128:145-155. [PMID: 23196234 PMCID: PMC4106359 DOI: 10.1016/j.biortech.2012.10.087] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Revised: 10/16/2012] [Accepted: 10/19/2012] [Indexed: 05/23/2023]
Abstract
A novel xylanase gene, xyn10A, was cloned from Flavobacterium johsoniae, overexpressed in a flavobacterial expression system, the recombinant enzyme purified by Ni-affinity chromatography, and enzyme structure and activity analyzed. Xyn10A was found to be a modular xylanase with an Fn3 accessory domain on its N-terminal and a catalytic region on the C-terminal. The optimum pH and temperature for Xyn10A was 8.0 and 30 °C, but Xyn10A retained 50% activity at 4 °C, indicating that Xyn10A is a cold-active xylanase. A Fn3-deletion xylanase had relative activity ca. 3.6-fold lower than the wild-type, indicating that Fn3 promotes xylanase activity. The Fn3 region also contributed to stability of the enzyme at elevated temperatures. However, Fn3 did not bind this xylanase to insoluble substrates. The enzyme hydrolyzed xylo-oligosaccharides into xylobiose, and xylose with xylobiose as the main product, confirming that Xyn10A is a strict endo-β-1,4-xylanase. Xyn10A also hydrolyzed birchwood and beechwood xylan to yield mainly xylose, xylobiose and xylotriose.
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Affiliation(s)
- Shicheng Chen
- Dept of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.
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241
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Kumagai Y, Kawakami K, Mukaihara T, Kimura M, Hatanaka T. The structural analysis and the role of calcium binding site for thermal stability in mannanase. Biochimie 2012; 94:2783-90. [DOI: 10.1016/j.biochi.2012.09.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 09/13/2012] [Indexed: 10/27/2022]
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242
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Larroque M, Barriot R, Bottin A, Barre A, Rougé P, Dumas B, Gaulin E. The unique architecture and function of cellulose-interacting proteins in oomycetes revealed by genomic and structural analyses. BMC Genomics 2012; 13:605. [PMID: 23140525 PMCID: PMC3532174 DOI: 10.1186/1471-2164-13-605] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 10/25/2012] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Oomycetes are fungal-like microorganisms evolutionary distinct from true fungi, belonging to the Stramenopile lineage and comprising major plant pathogens. Both oomycetes and fungi express proteins able to interact with cellulose, a major component of plant and oomycete cell walls, through the presence of carbohydrate-binding module belonging to the family 1 (CBM1). Fungal CBM1-containing proteins were implicated in cellulose degradation whereas in oomycetes, the Cellulose Binding Elicitor Lectin (CBEL), a well-characterized CBM1-protein from Phytophthora parasitica, was implicated in cell wall integrity, adhesion to cellulosic substrates and induction of plant immunity. RESULTS To extend our knowledge on CBM1-containing proteins in oomycetes, we have conducted a comprehensive analysis on 60 fungi and 7 oomycetes genomes leading to the identification of 518 CBM1-containing proteins. In plant-interacting microorganisms, the larger number of CBM1-protein coding genes is expressed by necrotroph and hemibiotrophic pathogens, whereas a strong reduction of these genes is observed in symbionts and biotrophs. In fungi, more than 70% of CBM1-containing proteins correspond to enzymatic proteins in which CBM1 is associated with a catalytic unit involved in cellulose degradation. In oomycetes more than 90% of proteins are similar to CBEL in which CBM1 is associated with a non-catalytic PAN/Apple domain, known to interact with specific carbohydrates or proteins. Distinct Stramenopile genomes like diatoms and brown algae are devoid of CBM1 coding genes. A CBM1-PAN/Apple association 3D structural modeling was built allowing the identification of amino acid residues interacting with cellulose and suggesting the putative interaction of the PAN/Apple domain with another type of glucan. By Surface Plasmon Resonance experiments, we showed that CBEL binds to glycoproteins through galactose or N-acetyl-galactosamine motifs. CONCLUSIONS This study provides insight into the evolution and biological roles of CBM1-containing proteins from oomycetes. We show that while CBM1s from fungi and oomycetes are similar, they team up with different protein domains, either in proteins implicated in the degradation of plant cell wall components in the case of fungi or in proteins involved in adhesion to polysaccharidic substrates in the case of oomycetes. This work highlighted the unique role and evolution of CBM1 proteins in oomycete among the Stramenopile lineage.
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Affiliation(s)
- Mathieu Larroque
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
| | - Roland Barriot
- Université de Toulouse, UPS, Laboratoire de Microbiologie et Génétique Moléculaire, Toulouse F-31000, France
- Centre National de la Recherche Scientifique; LMGM, Toulouse F-31000, France
| | - Arnaud Bottin
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
| | - Annick Barre
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
- Present address: Université de Toulouse, UPS, Laboratoire PHARMA-DEV IRD UMR 152, 35 Chemin des Maraîchers, Toulouse 31400, France
| | - Pierre Rougé
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
- Present address: Université de Toulouse, UPS, Laboratoire PHARMA-DEV IRD UMR 152, 35 Chemin des Maraîchers, Toulouse 31400, France
| | - Bernard Dumas
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
| | - Elodie Gaulin
- Université de Toulouse, UPS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan, F-31326, France
- CNRS, Laboratoire de Recherche en Sciences Végétales, 24 chemin de Borde Rouge, BP42617, Auzeville, Castanet-Tolosan F-31326, France
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243
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Wakinaka T, Kiyohara M, Kurihara S, Hirata A, Chaiwangsri T, Ohnuma T, Fukamizo T, Katayama T, Ashida H, Yamamoto K. Bifidobacterial α-galactosidase with unique carbohydrate-binding module specifically acts on blood group B antigen. Glycobiology 2012; 23:232-40. [PMID: 23089618 DOI: 10.1093/glycob/cws142] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Bifidobacterium bifidum is one of the most frequently found bifidobacteria in the intestines of newborn infants. We previously reported that B. bifidum possesses unique metabolic pathways for O-linked glycans on gastrointestinal mucin (Yoshida E, Sakurama H, Kiyohara M, Nakajima M, Kitaoka M, Ashida H, Hirose J, Katayama T, Yamamoto K, Kumagai H. 2012. Bifidobacterium longum subsp. infantis uses two different β-galactosidases for selectively degrading type-1 and type-2 human milk oligosaccharides. Glycobiology. 22:361-368). The nonreducing termini of O-linked glycans on mucin are frequently covered with histo-blood group antigens. Here, we identified a gene agabb from B. bifidum JCM 1254, which encodes glycoside hydrolase (GH) family 110 α-galactosidase. AgaBb is a 1289-amino acid polypeptide containing an N-terminal signal sequence, a GH110 domain, a carbohydrate-binding module (CBM) 51 domain, a bacterial Ig-like (Big) 2 domain and a C-terminal transmembrane region, in this order. The recombinant enzyme expressed in Escherichia coli hydrolyzed α1,3-linked Gal in branched blood group B antigen [Galα1-3(Fucα1-2)Galβ1-R], but not in a linear xenotransplantation antigen (Galα1-3Galβ1-R). The enzyme also acted on group B human salivary mucin and erythrocytes. We also revealed that CBM51 specifically bound blood group B antigen using both isothermal titration calorimetry and a solid-phase binding assay, and it enhanced the affinity of the enzyme toward substrates with multivalent B antigens. We suggest that this enzyme plays an important role in degrading B antigens to acquire nutrients from mucin oligosaccharides in the gastrointestinal tracts.
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Affiliation(s)
- Takura Wakinaka
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
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244
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Vorhölter FJ, Wiggerich HG, Scheidle H, Sidhu VK, Mrozek K, Küster H, Pühler A, Niehaus K. Involvement of bacterial TonB-dependent signaling in the generation of an oligogalacturonide damage-associated molecular pattern from plant cell walls exposed to Xanthomonas campestris pv. campestris pectate lyases. BMC Microbiol 2012; 12:239. [PMID: 23082751 PMCID: PMC3551730 DOI: 10.1186/1471-2180-12-239] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 09/25/2012] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Efficient perception of attacking pathogens is essential for plants. Plant defense is evoked by molecules termed elicitors. Endogenous elicitors or damage-associated molecular patterns (DAMPs) originate from plant materials upon injury or pathogen activity. While there are comparably well-characterized examples for DAMPs, often oligogalacturonides (OGAs), generated by the activity of fungal pathogens, endogenous elicitors evoked by bacterial pathogens have been rarely described. In particular, the signal perception and transduction processes involved in DAMP generation are poorly characterized. RESULTS A mutant strain of the phytopathogenic bacterium Xanthomonas campestris pv. campestris deficient in exbD2, which encodes a component of its unusual elaborate TonB system, had impaired pectate lyase activity and caused no visible symptoms for defense on the non-host plant pepper (Capsicum annuum). A co-incubation of X. campestris pv. campestris with isolated cell wall material from C. annuum led to the release of compounds which induced an oxidative burst in cell suspension cultures of the non-host plant. Lipopolysaccharides and proteins were ruled out as elicitors by polymyxin B and heat treatment, respectively. After hydrolysis with trifluoroacetic acid and subsequent HPAE chromatography, the elicitor preparation contained galacturonic acid, the monosaccharide constituent of pectate. OGAs were isolated from this crude elicitor preparation by HPAEC and tested for their biological activity. While small OGAs were unable to induce an oxidative burst, the elicitor activity in cell suspension cultures of the non-host plants tobacco and pepper increased with the degree of polymerization (DP). Maximal elicitor activity was observed for DPs exceeding 8. In contrast to the X. campestris pv. campestris wild type B100, the exbD2 mutant was unable to generate elicitor activity from plant cell wall material or from pectin. CONCLUSIONS To our knowledge, this is the second report on a DAMP generated by bacterial features. The generation of the OGA elicitor is embedded in a complex exchange of signals within the framework of the plant-microbe interaction of C. annuum and X. campestris pv. campestris. The bacterial TonB-system is essential for the substrate-induced generation of extracellular pectate lyase activity. This is the first demonstration that a TonB-system is involved in bacterial trans-envelope signaling in the context of a pathogenic interaction with a plant.
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Affiliation(s)
- Frank-Jörg Vorhölter
- Department of Proteome and Metabolome Research, Faculty of Biology, Universität Bielefeld, Universitätsstr 25, Bielefeld 33615, Germany.
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245
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Cameron EA, Maynard MA, Smith CJ, Smith TJ, Koropatkin NM, Martens EC. Multidomain Carbohydrate-binding Proteins Involved in Bacteroides thetaiotaomicron Starch Metabolism. J Biol Chem 2012; 287:34614-25. [PMID: 22910908 PMCID: PMC3464567 DOI: 10.1074/jbc.m112.397380] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/10/2012] [Indexed: 12/18/2022] Open
Abstract
Human colonic bacteria are necessary for the digestion of many dietary polysaccharides. The intestinal symbiont Bacteroides thetaiotaomicron uses five outer membrane proteins to bind and degrade starch. Here, we report the x-ray crystallographic structures of SusE and SusF, two outer membrane proteins composed of tandem starch specific carbohydrate-binding modules (CBMs) with no enzymatic activity. Examination of the two CBMs in SusE and three CBMs in SusF reveals subtle differences in the way each binds starch and is reflected in their K(d) values for both high molecular weight starch and small maltooligosaccharides. Thus, each site seems to have a unique starch preference that may enable these proteins to interact with different regions of starch or its breakdown products. Proteins similar to SusE and SusF are encoded in many other polysaccharide utilization loci that are possessed by human gut bacteria in the phylum Bacteroidetes. Thus, these proteins are likely to play an important role in carbohydrate metabolism in these abundant symbiotic species. Understanding structural changes that diversify and adapt related proteins in the human gut microbial community will be critical to understanding the detailed mechanistic roles that they perform in the complex digestive ecosystem.
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Affiliation(s)
- Elizabeth A. Cameron
- From the Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109 and
| | - Mallory A. Maynard
- From the Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109 and
| | - Christopher J. Smith
- From the Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109 and
| | - Thomas J. Smith
- the Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Nicole M. Koropatkin
- From the Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109 and
- the Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Eric C. Martens
- From the Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan 48109 and
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Floudas D, Binder M, Riley R, Barry K, Blanchette RA, Henrissat B, Martínez AT, Otillar R, Spatafora JW, Yadav JS, Aerts A, Benoit I, Boyd A, Carlson A, Copeland A, Coutinho PM, de Vries RP, Ferreira P, Findley K, Foster B, Gaskell J, Glotzer D, Górecki P, Heitman J, Hesse C, Hori C, Igarashi K, Jurgens JA, Kallen N, Kersten P, Kohler A, Kües U, Kumar TKA, Kuo A, LaButti K, Larrondo LF, Lindquist E, Ling A, Lombard V, Lucas S, Lundell T, Martin R, McLaughlin DJ, Morgenstern I, Morin E, Murat C, Nagy LG, Nolan M, Ohm RA, Patyshakuliyeva A, Rokas A, Ruiz-Dueñas FJ, Sabat G, Salamov A, Samejima M, Schmutz J, Slot JC, St John F, Stenlid J, Sun H, Sun S, Syed K, Tsang A, Wiebenga A, Young D, Pisabarro A, Eastwood DC, Martin F, Cullen D, Grigoriev IV, Hibbett DS. The Paleozoic origin of enzymatic lignin decomposition reconstructed from 31 fungal genomes. Science 2012; 336:1715-9. [PMID: 22745431 DOI: 10.1126/science.1221748] [Citation(s) in RCA: 1012] [Impact Index Per Article: 84.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Wood is a major pool of organic carbon that is highly resistant to decay, owing largely to the presence of lignin. The only organisms capable of substantial lignin decay are white rot fungi in the Agaricomycetes, which also contains non-lignin-degrading brown rot and ectomycorrhizal species. Comparative analyses of 31 fungal genomes (12 generated for this study) suggest that lignin-degrading peroxidases expanded in the lineage leading to the ancestor of the Agaricomycetes, which is reconstructed as a white rot species, and then contracted in parallel lineages leading to brown rot and mycorrhizal species. Molecular clock analyses suggest that the origin of lignin degradation might have coincided with the sharp decrease in the rate of organic carbon burial around the end of the Carboniferous period.
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van Gool MP, van Muiswinkel GCJ, Hinz SWA, Schols HA, Sinitsyn AP, Gruppen H. Two GH10 endo-xylanases from Myceliophthora thermophila C1 with and without cellulose binding module act differently towards soluble and insoluble xylans. BIORESOURCE TECHNOLOGY 2012; 119:123-32. [PMID: 22728192 DOI: 10.1016/j.biortech.2012.05.117] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 05/22/2012] [Accepted: 05/22/2012] [Indexed: 05/02/2023]
Abstract
Xylanases are mostly classified as belonging to glycoside hydrolase (GH) family 10 and 11, which differ in catalytic properties and structures. However, within one family, differences may also be present. The influence of solubility and molecular structure of substrates towards the efficiency of two GH10 xylanases from Myceliophthora thermophila C1 was investigated. The xylanases differed in degradation of high and low substituted substrate and the substitution pattern was an important factor influencing their efficiency. Alkali-labile interactions, as well as the presence of cellulose within the complex cell wall structure hindered efficient hydrolysis for both xylanases. The presence of a carbohydrate binding module did not enhance the degradation of the substrates. The differences in degradation could be related to the protein structure of the two xylanases. The study shows that the classification of enzymes does not predict their performance towards various substrates.
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Affiliation(s)
- M P van Gool
- Laboratory of Food Chemistry, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands
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248
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Kumagai Y, Kawakami K, Uraji M, Hatanaka T. Binding of bivalent ions to actinomycete mannanase is accompanied by conformational change and is a key factor in its thermal stability. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1834:301-7. [PMID: 22985499 DOI: 10.1016/j.bbapap.2012.08.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 07/25/2012] [Accepted: 08/08/2012] [Indexed: 10/28/2022]
Abstract
The study aimed to define the key factors involved in the modulation of actinomycete mannanases. We focused on the roles of carbohydrate-binding modules (CBMs) and bivalent ions. To investigate the effects of these factors, two actinomycete mannanase genes were cloned from Streptomyces thermoluteus (StManII) and Streptomyces lividans (SlMan). CBMs fused to mannanase catalytic domains do not affect the thermal stability of the proteins. CBM2 of StManII increased the catalytic efficiency toward soluble-mannan and insoluble-mannan by 25%-36%, and CBM10 of SlMan increased the catalytic efficiency toward soluble-mannan by 40%-50%. Thermal stability of wild-type and mutant enzymes was enhanced by calcium and manganese. Thermal stability of SlMandC was also slightly enhanced by magnesium. These results indicated that bivalent ion-binding site responsible for thermal stability was in the catalytic domains. Thermal stability of mannanase differed in the kinds of bivalent ions. Isothermal titration calorimetry revealed that the catalytic domain of StManII bound bivalent ions with a K(a) of 5.39±0.45×10(3)-7.56±1.47×10(3)M(-1), and the catalytic domain of SlMan bound bivalent ions with a K(a) of 1.06±0.34×10(3)-3.86±0.94×10(3)M(-1). The stoichiometry of these bindings was consistent with one bivalent ion-binding site per molecule of enzyme. Circular dichroism spectrum revealed that the presence of bivalent ions induced changes in the secondary structures of the enzymes. The binding of certain bivalent ion responsible for thermal stability was accompanied by a different conformational change by each bivalent ion. Actinomycete mannanases belong to GHF5 which contained various hemicellulases; therefore, the information obtained from mannanases applies to the other enzymes.
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Affiliation(s)
- Yuya Kumagai
- Okayama Prefectural Technology Center for Agriculture, Forestry and Fisheries, Research Institute for Biological Sciences (RIBS), Okayama, 7549-1 Kibichuo-cho, Kaga-gun, Okayama 716-1241, Japan
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249
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Jiang TY, Ci YP, Chou WI, Lee YC, Sun YJ, Chou WY, Li KM, Chang MDT. Two unique ligand-binding clamps of Rhizopus oryzae starch binding domain for helical structure disruption of amylose. PLoS One 2012; 7:e41131. [PMID: 22815939 PMCID: PMC3398936 DOI: 10.1371/journal.pone.0041131] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/17/2012] [Indexed: 11/30/2022] Open
Abstract
The N-terminal starch binding domain of Rhizopus oryzae glucoamylase (RoSBD) has a high binding affinity for raw starch. RoSBD has two ligand-binding sites, each containing a ligand-binding clamp: a polyN clamp residing near binding site I is unique in that it is expressed in only three members of carbohydrate binding module family 21 (CBM21) members, and a Y32/F58 clamp located at binding site II is conserved in several CBMs. Here we characterized different roles of these sites in the binding of insoluble and soluble starches using an amylose-iodine complex assay, atomic force microscopy, isothermal titration calorimetry, site-directed mutagenesis, and structural bioinformatics. RoSBD induced the release of iodine from the amylose helical cavity and disrupted the helical structure of amylose type III, thereby significantly diminishing the thickness and length of the amylose type III fibrils. A point mutation in the critical ligand-binding residues of sites I and II, however, reduced both the binding affinity and amylose helix disruption. This is the first molecular model for structure disruption of the amylose helix by a non-hydrolytic CBM21 member. RoSBD apparently twists the helical amylose strands apart to expose more ligand surface for further SBD binding. Repeating the process triggers the relaxation and unwinding of amylose helices to generate thinner and shorter amylose fibrils, which are more susceptible to hydrolysis by glucoamylase. This model aids in understanding the natural roles of CBMs in protein-glycan interactions and contributes to potential molecular engineering of CBMs.
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Affiliation(s)
- Ting-Ying Jiang
- Institute of Molecular and Cellular Biology and Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Yuan-Pei Ci
- Institute of Molecular and Cellular Biology and Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Wei-I Chou
- Institute of Molecular and Cellular Biology and Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
- Simpson Biotech Company, Ltd., Taoyuan County, Taiwan, Republic of China
| | - Yuan-Chuan Lee
- Institute of Molecular and Cellular Biology and Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Yuh-Ju Sun
- Institute of Bioinformatics and Structural Biology and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Wei-Yao Chou
- Department of Computer Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Kun-Mou Li
- Institute of Bioinformatics and Structural Biology and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
| | - Margaret Dah-Tsyr Chang
- Institute of Molecular and Cellular Biology and Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
- * E-mail:
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250
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Wang Y, Tang R, Tao J, Wang X, Zheng B, Feng Y. Chimeric cellulase matrix for investigating intramolecular synergism between non-hydrolytic disruptive functions of carbohydrate-binding modules and catalytic hydrolysis. J Biol Chem 2012; 287:29568-78. [PMID: 22778256 DOI: 10.1074/jbc.m111.320358] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The conversion of renewable cellulosic biomass is of considerable interest for the production of biofuels and materials. The bottleneck in the efficient conversion is the compactness and resistance of crystalline cellulose. Carbohydrate-binding modules (CBMs), which disrupt crystalline cellulose via non-hydrolytic mechanisms, are expected to overcome this bottleneck. However, the lack of convenient methods for quantitative analysis of the disruptive functions of CBMs have hindered systematic studies and molecular modifications. Here we established a practical and systematic platform for quantifying and comparing the non-hydrolytic disruptive activities of CBMs via the synergism of CBMs and a catalytic module within designed chimeric cellulase molecules. Bioinformatics and computational biology were also used to provide a deeper understanding. A convenient vector was constructed to serve as a cellulase matrix into which heterologous CBM sequences can be easily inserted. The resulting chimeric cellulases were suitable for studying disruptive functions, and their activities quantitatively reflected the disruptive functions of CBMs on crystalline cellulose. In addition, this cellulase matrix can be used to construct novel chimeric cellulases with high hydrolytic activities toward crystalline cellulose.
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Affiliation(s)
- Yuguo Wang
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012, China
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