1
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Zhou Y, Rernglit W, Fukamizo T, Sucharitakul J, Suginta W. A three-step "ping-pong" mechanism of a GH20 β-N-acetylglucosaminidase from Vibrio campbellii belonging to a major Clade A-I of the phylogenetic tree of the enzyme superfamily. Biochem Biophys Res Commun 2024; 729:150357. [PMID: 39002194 DOI: 10.1016/j.bbrc.2024.150357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Accepted: 07/04/2024] [Indexed: 07/15/2024]
Abstract
β-N-acetylglucosaminidase (GlcNAcase) is an essential biocatalyst in chitin assimilation by marine Vibrio species, which rely on chitin as their main carbon source. Structure-based phylogenetic analysis of the GlcNAcase superfamily revealed that a GlcNAcase from Vibrio campbellii, formerly named V. harveyi, (VhGlcNAcase) belongs to a major clade, Clade A-I, of the phylogenetic tree. Pre-steady-state and steady-state kinetic analysis of the reaction catalysed by VhGlcNAcase with the fluorogenic substrate 4-methylumbelliferyl N-acetyl-β-D-glucosaminide suggested the following mechanism: (1) the Michaelis-Menten complex is formed in a rapid enzyme-substrate equilibrium with a Kd of 99.1 ± 1 μM. (2) The glycosidic bond is cleaved by the action of the catalytic residue Glu438, followed by the rapid release of the aglycone product with a rate constant (k2) of 53.3 ± 1 s-1. (3) After the formation of an oxazolinium ion intermediate with the assistance of Asp437, the anomeric carbon of the transition state is attacked by a catalytic water, followed by release of the glycone product with a rate constant (k3) of 14.6 s-1, which is rate-limiting. The result clearly indicated a three-step "ping-pong" mechanism for VhGlcNAcase.
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Affiliation(s)
- Yong Zhou
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand
| | - Waraporn Rernglit
- School of Chemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Tamo Fukamizo
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand.
| | - Jeerus Sucharitakul
- Department of Biochemistry, Faculty of Dentistry, Chulalongkorn University, Bangkok, 10330, Thailand.
| | - Wipa Suginta
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley, Rayong, 21210, Thailand.
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2
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Ohnuma T, Tsujii J, Kataoka C, Yoshimoto T, Takeshita D, Lampela O, Juffer AH, Suginta W, Fukamizo T. Periplasmic chitooligosaccharide-binding protein requires a three-domain organization for substrate translocation. Sci Rep 2023; 13:20558. [PMID: 37996461 PMCID: PMC10667598 DOI: 10.1038/s41598-023-47253-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 11/10/2023] [Indexed: 11/25/2023] Open
Abstract
Periplasmic solute-binding proteins (SBPs) specific for chitooligosaccharides, (GlcNAc)n (n = 2, 3, 4, 5 and 6), are involved in the uptake of chitinous nutrients and the negative control of chitin signal transduction in Vibrios. Most translocation processes by SBPs across the inner membrane have been explained thus far by two-domain open/closed mechanism. Here we propose three-domain mechanism of the (GlcNAc)n translocation based on experiments using a recombinant VcCBP, SBP specific for (GlcNAc)n from Vibrio cholerae. X-ray crystal structures of unliganded or (GlcNAc)3-liganded VcCBP solved at 1.2-1.6 Å revealed three distinct domains, the Upper1, Upper2 and Lower domains for this protein. Molecular dynamics simulation indicated that the motions of the three domains are independent and that in the (GlcNAc)3-liganded state the Upper2/Lower interface fluctuated more intensively, compared to the Upper1/Lower interface. The Upper1/Lower interface bound two GlcNAc residues tightly, while the Upper2/Lower interface appeared to loosen and release the bound sugar molecule. The three-domain mechanism proposed here was fully supported by binding data obtained by thermal unfolding experiments and ITC, and may be applicable to other translocation systems involving SBPs belonging to the same cluster.
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Affiliation(s)
- Takayuki Ohnuma
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan.
- Agricultural Technology and Innovation Research Institute (ATIRI), Kindai University, 3327-204, Nakamachi, Nara, 631-8505, Japan.
| | - Jun Tsujii
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
| | - Chikara Kataoka
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
| | - Teruki Yoshimoto
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
| | - Daijiro Takeshita
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba-Shi, Ibaraki, 305-8566, Japan
| | - Outi Lampela
- Biocenter Oulu, University of Oulu, P.O. Box 5000, FI-90014, Oulu, Finland
| | - André H Juffer
- Biocenter Oulu, University of Oulu, P.O. Box 5000, FI-90014, Oulu, Finland
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, P.O.Box 5000, FI-90014, Oulu, Finland
| | - Wipa Suginta
- School of Biomolecular Science & Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley 555 Moo 1 Payupnai, Wangchan, Rayong, 21210, Thailand
| | - Tamo Fukamizo
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan.
- School of Biomolecular Science & Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan Valley 555 Moo 1 Payupnai, Wangchan, Rayong, 21210, Thailand.
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3
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Raj S, Unsworth LD. Targeting active sites of inflammation using inherent properties of tissue-resident mast cells. Acta Biomater 2023; 159:21-37. [PMID: 36657696 DOI: 10.1016/j.actbio.2023.01.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 12/12/2022] [Accepted: 01/10/2023] [Indexed: 01/18/2023]
Abstract
Mast cells play a pivotal role in initiating and directing host's immune response. They reside in tissues that primarily interface with the external environment. Activated mast cells respond to environmental cues throughout acute and chronic inflammation through releasing immune mediators via rapid degranulation, or long-term de novo expression. Mast cell activation results in the rapid release of a variety of unique enzymes and reactive oxygen species. Furthermore, the increased density of mast cell unique receptors like mas related G protein-coupled receptor X2 also characterizes the inflamed tissues. The presence of these molecules (either released mediators or surface receptors) are particular to the sites of active inflammation, and are a result of mast cell activation. Herein, the molecular design principles for capitalizing on these novel mast cell properties is discussed with the goal of manipulating localized inflammation. STATEMENT OF SIGNIFICANCE: Mast cells are immune regulating cells that play a crucial role in both innate and adaptive immune responses. The activation of mast cells causes the release of multiple unique profiles of biomolecules, which are specific to both tissue and disease. These unique characteristics are tightly regulated and afford a localized stimulus for targeting inflammatory diseases. Herein, these important mast cell attributes are discussed in the frame of highlighting strategies for the design of bioresponsive functional materials to target regions of inflammations.
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Affiliation(s)
- Shammy Raj
- Department of Chemical and Materials Engineering, Donadeo Innovation Centre for Engineering, 9211-116 Street NW, University of Alberta, Edmonton, AB, T6G1H9, Canada
| | - Larry D Unsworth
- Department of Chemical and Materials Engineering, Donadeo Innovation Centre for Engineering, 9211-116 Street NW, University of Alberta, Edmonton, AB, T6G1H9, Canada.
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4
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Jiang WX, Li PY, Chen XL, Zhang YS, Wang JP, Wang YJ, Sheng Q, Sun ZZ, Qin QL, Ren XB, Wang P, Song XY, Chen Y, Zhang YZ. A pathway for chitin oxidation in marine bacteria. Nat Commun 2022; 13:5899. [PMID: 36202810 PMCID: PMC9537276 DOI: 10.1038/s41467-022-33566-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 09/22/2022] [Indexed: 11/09/2022] Open
Abstract
Oxidative degradation of chitin, initiated by lytic polysaccharide monooxygenases (LPMOs), contributes to microbial bioconversion of crystalline chitin, the second most abundant biopolymer in nature. However, our knowledge of oxidative chitin utilization pathways, beyond LPMOs, is very limited. Here, we describe a complete pathway for oxidative chitin degradation and its regulation in a marine bacterium, Pseudoalteromonas prydzensis. The pathway starts with LPMO-mediated extracellular breakdown of chitin into C1-oxidized chitooligosaccharides, which carry a terminal 2-(acetylamino)-2-deoxy-D-gluconic acid (GlcNAc1A). Transmembrane transport of oxidized chitooligosaccharides is followed by their hydrolysis in the periplasm, releasing GlcNAc1A, which is catabolized in the cytoplasm. This pathway differs from the known hydrolytic chitin utilization pathway in enzymes, transporters and regulators. In particular, GlcNAc1A is converted to 2-keto-3-deoxygluconate 6-phosphate, acetate and NH3 via a series of reactions resembling the degradation of D-amino acids rather than other monosaccharides. Furthermore, genomic and metagenomic analyses suggest that the chitin oxidative utilization pathway may be prevalent in marine Gammaproteobacteria.
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Affiliation(s)
- Wen-Xin Jiang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Ping-Yi Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China. .,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China.
| | - Xiu-Lan Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Yi-Shuo Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Jing-Ping Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yan-Jun Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Qi Sheng
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Zhong-Zhi Sun
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Qi-Long Qin
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Xue-Bing Ren
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Peng Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao, China.,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
| | - Xiao-Yan Song
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yin Chen
- College of Marine Life Sciences, Ocean University of China, Qingdao, China.,School of Life Sciences, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - Yu-Zhong Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao, China. .,Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China. .,Marine Biotechnology Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.
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5
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Suginta W, Sanram S, Aunkham A, Winterhalter M, Schulte A. The C2 entity of chitosugars is crucial in molecular selectivity of the Vibrio campbellii chitoporin. J Biol Chem 2021; 297:101350. [PMID: 34715124 PMCID: PMC8608610 DOI: 10.1016/j.jbc.2021.101350] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 10/21/2021] [Accepted: 10/22/2021] [Indexed: 12/14/2022] Open
Abstract
The marine bacterium Vibrio campbellii expresses a chitooligosaccharide-specific outer-membrane channel (chitoporin) for the efficient uptake of nutritional chitosugars that are externally produced through enzymic degradation of environmental host shell chitin. However, the principles behind the distinct substrate selectivity of chitoporins are unclear. Here, we employed black lipid membrane (BLM) electrophysiology, which handles the measurement of the flow of ionic current through porins in phospholipid bilayers for the assessment of porin conductivities, to investigate the pH dependency of chitosugar-chitoporin interactions for the bacterium's natural substrate chitohexaose and its deacetylated form, chitosan hexaose. We show that efficient passage of the N-acetylated chitohexaose through the chitoporin is facilitated by its strong affinity for the pore. In contrast, the deacetylated chitosan hexaose is impermeant; however, protonation of the C2 amino entities of chitosan hexaose allows it to be pulled through the channel in the presence of a transmembrane electric field. We concluded from this the crucial role of C2-substitution as the determining factor for chitoporin entry. A change from N-acetylamino- to amino-substitution effectively abolished the ability of approaching molecules to enter the chitoporin, with deacetylation leading to loss of the distinctive structural features of nanopore opening and pore access of chitosugars. These findings provide further understanding of the multistep pathway of chitin utilization by marine Vibrio bacteria and may guide the development of solid-state or genetically engineered biological nanopores for relevant technological applications.
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Affiliation(s)
- Wipa Suginta
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, Thailand.
| | - Surapoj Sanram
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, Thailand
| | - Anuwat Aunkham
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, Thailand
| | - Mathias Winterhalter
- Department of Life Sciences and Chemistry, Jacobs University Bremen, Bremen, Germany
| | - Albert Schulte
- School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, Thailand.
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6
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Fennell TG, Blackwell GA, Thomson NR, Dorman MJ. gbpA and chiA genes are not uniformly distributed amongst diverse Vibrio cholerae. Microb Genom 2021; 7:000594. [PMID: 34100695 PMCID: PMC8461464 DOI: 10.1099/mgen.0.000594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/26/2021] [Indexed: 11/18/2022] Open
Abstract
Members of the bacterial genus Vibrio utilize chitin both as a metabolic substrate and a signal to activate natural competence. Vibrio cholerae is a bacterial enteric pathogen, sub-lineages of which can cause pandemic cholera. However, the chitin metabolic pathway in V. cholerae has been dissected using only a limited number of laboratory strains of this species. Here, we survey the complement of key chitin metabolism genes amongst 195 diverse V. cholerae. We show that the gene encoding GbpA, known to be an important colonization and virulence factor in pandemic isolates, is not ubiquitous amongst V. cholerae. We also identify a putatively novel chitinase, and present experimental evidence in support of its functionality. Our data indicate that the chitin metabolic pathway within V. cholerae is more complex than previously thought, and emphasize the importance of considering genes and functions in the context of a species in its entirety, rather than simply relying on traditional reference strains.
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Affiliation(s)
- Thea G. Fennell
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
- Churchill College, Storey’s Way, Cambridge, CB3 0DS, UK
- Present address: Sainsbury Laboratory, University of Cambridge, Bateman Street, Cambridge, UK
| | - Grace A. Blackwell
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
- EMBL-EBI, Wellcome Genome Campus, Hinxton, CB10 1SD, UK
| | - Nicholas R. Thomson
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
- London School of Hygiene and Tropical Medicine, Keppel St., Bloomsbury, London, WC1E 7HT, UK
| | - Matthew J. Dorman
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
- Churchill College, Storey’s Way, Cambridge, CB3 0DS, UK
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7
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Morimoto Y, Takahashi S, Isoda Y, Nokami T, Fukamizo T, Suginta W, Ohnuma T. Kinetic and thermodynamic insights into the inhibitory mechanism of TMG-chitotriomycin on Vibrio campbellii GH20 exo-β-N-acetylglucosaminidase. Carbohydr Res 2020; 499:108201. [PMID: 33243428 DOI: 10.1016/j.carres.2020.108201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 11/10/2020] [Accepted: 11/11/2020] [Indexed: 12/20/2022]
Abstract
We investigated the inhibition kinetics of VhGlcNAcase, a GH20 exo-β-N-acetylglucosaminidase (GlcNAcase) from the marine bacterium Vibrio campbellii (formerly V. harveyi) ATCC BAA-1116, using TMG-chitotriomycin, a natural enzyme inhibitor specific for GH20 GlcNAcases from chitin-processing organisms, with p-nitrophenyl N-acetyl-β-d-glucosaminide (pNP-GlcNAc) as the substrate. TMG-chitotriomycin inhibited VhGlcNAcase with an IC50 of 3.0 ± 0.7 μM. Using Dixon plots, the inhibition kinetics indicated that TMG-chitotriomycin is a competitive inhibitor, with an inhibition constant Ki of 2.2 ± 0.3 μM. Isothermal titration calorimetry experiments provided the thermodynamic parameters for the binding of TMG-chitotriomycin to VhGlcNAcase and revealed that binding was driven by both favorable enthalpy and entropy changes (ΔH° = -2.5 ± 0.1 kcal/mol and -TΔS° = -5.8 ± 0.3 kcal/mol), resulting in a free energy change, ΔG°, of -8.2 ± 0.2 kcal/mol. Dissection of the entropic term showed that a favorable solvation entropy change (-TΔSsolv° = -16 ± 2 kcal/mol) is the main contributor to the entropic term.
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Affiliation(s)
- Yusuke Morimoto
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan
| | - Shuji Takahashi
- Department of Chemistry and Biotechnology, Tottori University, 4-101 Koyama-minami, Tottori, 680-8552, Japan
| | - Yuta Isoda
- Department of Chemistry and Biotechnology, Tottori University, 4-101 Koyama-minami, Tottori, 680-8552, Japan
| | - Toshiki Nokami
- Department of Chemistry and Biotechnology, Tottori University, 4-101 Koyama-minami, Tottori, 680-8552, Japan
| | - Tamo Fukamizo
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan; School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Tumbol Payupnai, Wangchan Valley, Rayong, 21210, Thailand
| | - Wipa Suginta
- School of Biomolecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Tumbol Payupnai, Wangchan Valley, Rayong, 21210, Thailand
| | - Takayuki Ohnuma
- Department of Advanced Bioscience, Kindai University, 3327-204 Nakamachi, Nara, 631-8505, Japan; Agricultural Technology and Innovation Research Institute, Kindai University, Nara, Japan.
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8
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Regulation of Chitin-Dependent Growth and Natural Competence in Vibrio parahaemolyticus. Microorganisms 2020; 8:microorganisms8091303. [PMID: 32859005 PMCID: PMC7564644 DOI: 10.3390/microorganisms8091303] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 02/06/2023] Open
Abstract
Vibrios can degrade chitin surfaces to soluble N-acetyl glucosamine oligosaccharides (GlcNAcn) that can be utilized as a carbon source and also induce a state of natural genetic competence. In this study, we characterized chitin-dependent growth and natural competence in Vibrio parahaemolyticus and its regulation. We found that growth on chitin was regulated through chitin sensors ChiS (sensor histidine kinase) and TfoS (transmembrane transcriptional regulator) by predominantly controlling the expression of chitinase VPA0055 (ChiA2) in a TfoX-dependent manner. The reduced growth of ΔchiA2, ΔchiS and ΔtfoS mutants highlighted the critical role played by ChiA2 in chitin breakdown. This growth defect of ΔchiA2 mutant could be recovered when chitin oligosaccharides GlcNAc2 or GlcNAc6 were supplied instead of chitin. The ΔtfoS mutant was also able to grow on GlcNAc2 but the ΔchiS mutant could not, which indicates that GlcNAc2 catabolic operon is dependent on ChiS and independent of TfoS. However, the ΔtfoS mutant was unable to utilize GlcNAc6 because the periplasmic enzymes required for the breakdown of GlcNAc6 were found to be downregulated at the mRNA level. We also showed that natural competence can be induced only by GlcNAc6, not GlcNAc2, because the expression of competence genes was significantly higher in the presence of GlcNAc6 compared to GlcNAc2. Moreover, this might be an indication that GlcNAc2 and GlcNAc6 were detected by different receptors. Therefore, we speculate that GlcNAc2-dependent activation of ChiS and GlcNAc6-dependent activation of TfoS might be crucial for the induction of natural competence in V. parahaemolyticus through the upregulation of the master competence regulator TfoX.
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Li RK, Hu YJ, Ng TB, Guo BQ, Zhou ZH, Zhao J, Ye XY. Expression and biochemical characterization of a novel chitinase ChiT-7 from the metagenome in the soil of a mangrove tidal flat in China. Int J Biol Macromol 2020; 158:1125-1134. [PMID: 32360969 DOI: 10.1016/j.ijbiomac.2020.04.242] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 04/25/2020] [Accepted: 04/27/2020] [Indexed: 12/18/2022]
Abstract
Chitinases play an important role in the process of chitin bioavailability. In this study, we cloned a new chitinase gene and characterized its recombinant protein. The new 1251 bp gene of chitinase (ChiT-7) was cloned from the metagenome of the mangrove tidal flat soil in the city of Zhangzhou in Fujian Province (China) by genome walking. The gene encoded a mature protein with 381 amino acids, which manifested certain sequence similarity (59% identity) to characterized GH18 chitinases. The mature protein of ChiT-7 was successfully expressed in E. coli BL21 (DE3). After purification, the specific activity of the recombinant enzyme was 0.63 U/mg at the optimal pH of 6.0 and the optimal temperature of 45 °C. The rChiT-7 was active over a wide pH range, and the residual enzyme activity reached 80% or higher at 30 °C-50 °C. rChiT-7 hydrolyzed colloidal chitin with (GlcNAc)2 and GlcNAc as the main final products. Structural analysis of ChiT-7 indicated that ChiT-7 could be a processive chitinase. rChiT-7 manifested characteristics analogous to those of fungi and actinomycetes and exhibited sequence homology.
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Affiliation(s)
- Ren Kuan Li
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China; National Engineering Laboratory for High-efficient Enzyme Expression, PR China
| | - Ya Juan Hu
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Tzi Bun Ng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Bing Qi Guo
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Zi He Zhou
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Jing Zhao
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China
| | - Xiu Yun Ye
- The Key Laboratory of Marine Enzyme Engineering of Fujian Province, Fuzhou University, PR China; National Engineering Laboratory for High-efficient Enzyme Expression, PR China.
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10
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Identification and Characterization of a β- N-Acetylhexosaminidase with a Biosynthetic Activity from the Marine Bacterium Paraglaciecola hydrolytica S66 T. Int J Mol Sci 2020; 21:ijms21020417. [PMID: 31936522 PMCID: PMC7014002 DOI: 10.3390/ijms21020417] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 01/04/2020] [Accepted: 01/07/2020] [Indexed: 11/24/2022] Open
Abstract
β-N-Acetylhexosaminidases are glycoside hydrolases (GHs) acting on N-acetylated carbohydrates and glycoproteins with the release of N-acetylhexosamines. Members of the family GH20 have been reported to catalyze the transfer of N-acetylglucosamine (GlcNAc) to an acceptor, i.e., the reverse of hydrolysis, thus representing an alternative to chemical oligosaccharide synthesis. Two putative GH20 β-N-acetylhexosaminidases, PhNah20A and PhNah20B, encoded by the marine bacterium Paraglaciecola hydrolytica S66T, are distantly related to previously characterized enzymes. Remarkably, PhNah20A was located by phylogenetic analysis outside clusters of other studied β-N-acetylhexosaminidases, in a unique position between bacterial and eukaryotic enzymes. We successfully produced recombinant PhNah20A showing optimum activity at pH 6.0 and 50 °C, hydrolysis of GlcNAc β-1,4 and β-1,3 linkages in chitobiose (GlcNAc)2 and GlcNAc-1,3-β-Gal-1,4-β-Glc (LNT2), a human milk oligosaccharide core structure. The kinetic parameters of PhNah20A for p-nitrophenyl-GlcNAc and p-nitrophenyl-GalNAc were highly similar: kcat/KM being 341 and 344 mM−1·s−1, respectively. PhNah20A was unstable in dilute solution, but retained full activity in the presence of 0.5% bovine serum albumin (BSA). PhNah20A catalyzed the formation of LNT2, the non-reducing trisaccharide β-Gal-1,4-β-Glc-1,1-β-GlcNAc, and in low amounts the β-1,2- or β-1,3-linked trisaccharide β-Gal-1,4(β-GlcNAc)-1,x-Glc by a transglycosylation of lactose using 2-methyl-(1,2-dideoxy-α-d-glucopyrano)-oxazoline (NAG-oxazoline) as the donor. PhNah20A is the first characterized member of a distinct subgroup within GH20 β-N-acetylhexosaminidases.
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11
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Meekrathok P, Thongsom S, Aunkham A, Kaewmaneewat A, Kitaoku Y, Choowongkomon K, Suginta W. Novel GH-20 β-N-acetylglucosaminidase inhibitors: Virtual screening, molecular docking, binding affinity, and anti-tumor activity. Int J Biol Macromol 2020; 142:503-512. [DOI: 10.1016/j.ijbiomac.2019.09.122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 09/15/2019] [Accepted: 09/16/2019] [Indexed: 01/05/2023]
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12
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Fukamizo T, Kitaoku Y, Suginta W. Periplasmic solute-binding proteins: Structure classification and chitooligosaccharide recognition. Int J Biol Macromol 2019; 128:985-993. [PMID: 30771387 DOI: 10.1016/j.ijbiomac.2019.02.064] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 01/12/2019] [Accepted: 02/11/2019] [Indexed: 12/17/2022]
Abstract
Periplasmic solute-binding proteins (SBPs) serve as molecular shuttles that assist the transport of small solutes from the outer membrane to the inner membrane of all Gram-negative bacteria. Based on the available crystal structures, SBPs are classified into seven clusters, A-G, and are further divided into subclusters, IV. This minireview is focused on the classification, structure and substrate specificity of a distinct class of SBPs specific for chitooligosaccharides (CBPs). To date, only two structures of CBP homologues, VhCBP and VcCBP, have been reported in the marine Vibrio species, with exposition of their limited function. The Vibrio CBPs are structurally classified as cluster C/subcluster IV SBPs that exclusively recognize β-1,4- or β-1,3-linked linear oligosaccharides. The overall structural feature of the Vibrios CBPs is most similar to the cellobiose-binding orthologue from the hyperthermophilic bacterium Thermotoga maritima. This similarity provides an opportunity to engineer the substrate specificity of the proteins and to control the uptake of chitinous and cellulosic nutrients in marine bacteria.
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Affiliation(s)
- Tamo Fukamizo
- Biochemistry and Electrochemistry Research Unit and School of Chemistry, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Yoshihito Kitaoku
- Biochemistry and Electrochemistry Research Unit and School of Chemistry, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Wipa Suginta
- Biochemistry and Electrochemistry Research Unit and School of Chemistry, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand; School of Biomolecular Science and Engineering (BSE), Vidyasirimedhi Institute of Science and Technology (VISTEC), Payupnai, Wangchan, Rayong 21210, Thailand.
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13
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Revisiting glycoside hydrolase family 20 β-N-acetyl-d-hexosaminidases: Crystal structures, physiological substrates and specific inhibitors. Biotechnol Adv 2018; 36:1127-1138. [DOI: 10.1016/j.biotechadv.2018.03.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 03/18/2018] [Accepted: 03/19/2018] [Indexed: 12/31/2022]
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14
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Krolicka M, Hinz SWA, Koetsier MJ, Eggink G, van den Broek LAM, Boeriu CG. β-N-Acetylglucosaminidase MthNAG from Myceliophthora thermophila C1, a thermostable enzyme for production of N-acetylglucosamine from chitin. Appl Microbiol Biotechnol 2018; 102:7441-7454. [PMID: 29943052 PMCID: PMC6097783 DOI: 10.1007/s00253-018-9166-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 06/07/2018] [Accepted: 06/09/2018] [Indexed: 11/30/2022]
Abstract
Thermostable enzymes are a promising alternative for chemical catalysts currently used for the production of N-acetylglucosamine (GlcNAc) from chitin. In this study, a novel thermostable β-N-acetylglucosaminidase MthNAG was cloned and purified from the thermophilic fungus Myceliophthora thermophila C1. MthNAG is a protein with a molecular weight of 71 kDa as determined with MALDI-TOF-MS. MthNAG has the highest activity at 50 °C and pH 4.5. The enzyme shows high thermostability above the optimum temperature: at 55 °C (144 h, 75% activity), 60 °C (48 h, 85% activity; half-life 82 h), and 70 °C (24 h, 33% activity; half-life 18 h). MthNAG releases GlcNAc from chitin oligosaccharides (GlcNAc)2–5, p-nitrophenol derivatives of chitin oligosaccharides (GlcNAc)1–3-pNP, and the polymeric substrates swollen chitin and soluble chitosan. The highest activity was detected towards (GlcNAc)2. MthNAG released GlcNAc from the non-reducing end of the substrate. We found that MthNAG and Chitinase Chi1 from M. thermophila C1 synergistically degraded swollen chitin and released GlcNAc in concentration of approximately 130 times higher than when only MthNAG was used. Therefore, chitinase Chi1 and MthNAG have great potential in the industrial production of GlcNAc.
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Affiliation(s)
- Malgorzata Krolicka
- Department of Bioprocess Engineering, Wageningen University, Wageningen, The Netherlands
| | | | | | - Gerrit Eggink
- Department of Bioprocess Engineering, Wageningen University, Wageningen, The Netherlands.,Wageningen Food & Biobased Research, Wageningen, The Netherlands
| | | | - Carmen G Boeriu
- Wageningen Food & Biobased Research, Wageningen, The Netherlands.
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15
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Structural basis for chitin acquisition by marine Vibrio species. Nat Commun 2018; 9:220. [PMID: 29335469 PMCID: PMC5768706 DOI: 10.1038/s41467-017-02523-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 12/07/2017] [Indexed: 11/18/2022] Open
Abstract
Chitin, an insoluble polymer of N-acetylglucosamine, is one of the most abundant biopolymers on Earth. By degrading chitin, chitinolytic bacteria such as Vibrio harveyi are critical for chitin recycling and maintenance of carbon and nitrogen cycles in the world’s oceans. A decisive step in chitin degradation is the uptake of chito-oligosaccharides by an outer membrane protein channel named chitoporin (ChiP). Here, we report X-ray crystal structures of ChiP from V. harveyi in the presence and absence of chito-oligosaccharides. Structures without bound sugar reveal a trimeric assembly with an unprecedented closing of the transport pore by the N-terminus of a neighboring subunit. Substrate binding ejects the pore plug to open the transport channel. Together with molecular dynamics simulations, electrophysiology and in vitro transport assays our data provide an explanation for the exceptional affinity of ChiP for chito-oligosaccharides and point to an important role of the N-terminal gate in substrate transport. Chitin degrading bacteria are important for marine ecosystems. Here the authors structurally and functionally characterize the Vibrio harveyi outer membrane diffusion channel chitoporin and give mechanistic insights into chito-oligosaccharide uptake.
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16
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Enzymatic properties of β-N-acetylglucosaminidases. Appl Microbiol Biotechnol 2017; 102:93-103. [PMID: 29143882 DOI: 10.1007/s00253-017-8624-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 11/02/2017] [Accepted: 11/02/2017] [Indexed: 01/27/2023]
Abstract
β-N-Acetylglucosaminidases (GlcNAcases) hydrolyse N-acetylglucosamine-containing oligosaccharides and proteins. These enzymes produce N-acetylglucosamine (GlcNAc) and have a wide range of promising applications in the food, energy, and pharmaceutical industries, such as synergistic degradation of chitin with endo-chitinases and using GlcNAc to produce sialic acid, bioethanol, single-cell proteins, and pharmaceutical therapeutics. GlcNAcases also play an important role in the dynamic balance of cellular O-linked GlcNAc levels, catabolism of ganglioside storage in Tay-Sachs disease, and bacterial cell wall recycling and flagellar assembly. In view of these important biological functions and the wide range of industrial applications of GlcNAcases, this review aims to provide a better understanding of various advances for these enzymes. It focuses on enzymatic properties of GlcNAcases, including substrate specificity, catalytic activity, pH optimum, temperature optimum, thermostability, the effects of various metal ions and organic reagents, and transglycosylation.
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17
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Chitinase Expression in Listeria monocytogenes Is Influenced by lmo0327, Which Encodes an Internalin-Like Protein. Appl Environ Microbiol 2017; 83:AEM.01283-17. [PMID: 28887418 PMCID: PMC5666140 DOI: 10.1128/aem.01283-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 08/23/2017] [Indexed: 02/02/2023] Open
Abstract
The chitinolytic system of Listeria monocytogenes thus far comprises two chitinases, ChiA and ChiB, and a lytic polysaccharide monooxygenase, Lmo2467. The role of the system in the bacterium appears to be pleiotropic, as besides mediating the hydrolysis of chitin, the second most ubiquitous carbohydrate in nature, the chitinases have been deemed important for the colonization of unicellular molds, as well as mammalian hosts. To identify additional components of the chitinolytic system, we screened a transposon mutant library for mutants exhibiting impaired chitin hydrolysis. The screening yielded a mutant with a transposon insertion in a locus corresponding to lmo0327 of the EGD-e strain. lmo0327 encodes a large (1,349 amino acids [aa]) cell wall-associated protein that has been proposed to possess murein hydrolase activity. The single inactivation of lmo0327, as well as of lmo0325 that codes for a putative transcriptional regulator functionally related to lmo0327, led to an almost complete abolishment of chitinolytic activity. The effect could be traced at the transcriptional level, as both chiA and chiB transcripts were dramatically decreased in the lmo0327 mutant. In accordance with that, we could barely detect ChiA and ChiB in the culture supernatants of the mutant strain. Our results provide new information regarding the function of the lmo0325-lmo0327 locus in L. monocytogenes and link it to the expression of chitinolytic activity. IMPORTANCE Many bacteria from terrestrial and marine environments express chitinase activities enabling them to utilize chitin as the sole source of carbon and nitrogen. Interestingly, several bacterial chitinases may also be involved in host pathogenesis. For example, in the important foodborne pathogen Listeria monocytogenes, the chitinases ChiA and ChiB and the lytic polysaccharide monooxygenase Lmo2467 are implicated in chitin assimilation but also act as virulence factors during the infection of mammalian hosts. Therefore, it is important to identify their regulators and induction cues to understand how the different roles of the chitinolytic system are controlled and mediated. Here, we provide evidence for the importance of lmo0327 and lmo0325, encoding a putative internalin/autolysin and a putative transcriptional activator, respectively, in the efficient expression of chitinase activity in L. monocytogenes and thereby provide new information regarding the function of the lmo0325-lmo0327 locus.
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18
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Glucose-Specific Enzyme IIA of the Phosphoenolpyruvate:Carbohydrate Phosphotransferase System Modulates Chitin Signaling Pathways in Vibrio cholerae. J Bacteriol 2017; 199:JB.00127-17. [PMID: 28461445 DOI: 10.1128/jb.00127-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 04/21/2017] [Indexed: 12/13/2022] Open
Abstract
In Vibrio cholerae, the genes required for chitin utilization and natural competence are governed by the chitin-responsive two-component system (TCS) sensor kinase ChiS. In the classical TCS paradigm, a sensor kinase specifically phosphorylates a cognate response regulator to activate gene expression. However, our previous genetic study suggested that ChiS stimulates the non-TCS transcriptional regulator TfoS by using mechanisms distinct from classical phosphorylation reactions (S. Yamamoto, J. Mitobe, T. Ishikawa, S. N. Wai, M. Ohnishi, H. Watanabe, and H. Izumiya, Mol Microbiol 91:326-347, 2014, https://doi.org/10.1111/mmi.12462). TfoS specifically activates the transcription of tfoR, encoding a small regulatory RNA essential for competence gene expression. Whether ChiS and TfoS interact directly remains unknown. To determine if other factors mediate the communication between ChiS and TfoS, we isolated transposon mutants that turned off tfoR::lacZ expression but possessed intact chiS and tfoS genes. We demonstrated an unexpected association of chitin-induced signaling pathways with the glucose-specific enzyme IIA (EIIAglc) of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) for carbohydrate uptake and catabolite control of gene expression. Genetic and physiological analyses revealed that dephosphorylated EIIAglc inactivated natural competence and tfoR transcription. Chitin-induced expression of the chb operon, which is required for chitin transport and catabolism, was also repressed by dephosphorylated EIIAglc Furthermore, the regulation of tfoR and chb expression by EIIAglc was dependent on ChiS and intracellular levels of ChiS were not affected by disruption of the gene encoding EIIAglc These results define a previously unknown connection between the PTS and chitin signaling pathways in V. cholerae and suggest a strategy whereby this bacterium can physiologically adapt to the existing nutrient status.IMPORTANCE The EIIAglc protein of the PTS coordinates a wide variety of physiological functions with carbon availability. In this report, we describe an unexpected association of chitin-activated signaling pathways in V. cholerae with EIIAglc The signaling pathways are governed by the chitin-responsive TCS sensor kinase ChiS and lead to the induction of chitin utilization and natural competence. We show that dephosphorylated EIIAglc inhibits both signaling pathways in a ChiS-dependent manner. This inhibition is different from classical catabolite repression that is caused by lowered levels of cyclic AMP. This work represents a newly identified connection between the PTS and chitin signaling pathways in V. cholerae and suggests a strategy whereby this bacterium can physiologically adapt to the existing nutrient status.
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19
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Hayes CA, Dalia TN, Dalia AB. Systematic genetic dissection of chitin degradation and uptake in Vibrio cholerae. Environ Microbiol 2017; 19:4154-4163. [PMID: 28752963 DOI: 10.1111/1462-2920.13866] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 07/11/2017] [Accepted: 07/21/2017] [Indexed: 12/21/2022]
Abstract
Vibrio cholerae is a natural resident of the aquatic environment, where a common nutrient is the chitinous exoskeletons of microscopic crustaceans. Chitin utilization requires chitinases, which degrade this insoluble polymer into soluble chitin oligosaccharides. These oligosaccharides also serve as an inducing cue for natural transformation in Vibrio species. There are 7 predicted endochitinase-like genes in the V. cholerae genome. Here, we systematically dissect the contribution of each gene to growth on chitin as well as induction of natural transformation. Specifically, we created a strain that lacks all 7 putative chitinases and from this strain, generated a panel of strains where each expresses a single chitinase. We also generated expression plasmids to ectopically express all 7 chitinases in our chitinase deficient strain. Through this analysis, we found that low levels of chitinase activity are sufficient for natural transformation, while growth on insoluble chitin as a sole carbon source requires more robust and concerted chitinase activity. We also assessed the role that the three uptake systems for the chitin degradation products GlcNAc, (GlcNAc)2 and (GlcN)2 , play in chitin utilization and competence induction. Cumulatively, this study provides mechanistic details for how this pathogen utilizes chitin to thrive and evolve in its environmental reservoir.
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Affiliation(s)
- Chelsea A Hayes
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - Triana N Dalia
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - Ankur B Dalia
- Department of Biology, Indiana University, Bloomington, IN, USA
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20
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Klancher CA, Hayes CA, Dalia AB. The nucleoid occlusion protein SlmA is a direct transcriptional activator of chitobiose utilization in Vibrio cholerae. PLoS Genet 2017; 13:e1006877. [PMID: 28683122 PMCID: PMC5519180 DOI: 10.1371/journal.pgen.1006877] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 07/20/2017] [Accepted: 06/19/2017] [Indexed: 12/22/2022] Open
Abstract
Chitin utilization by the cholera pathogen Vibrio cholerae is required for its persistence and evolution via horizontal gene transfer in the marine environment. Genes involved in the uptake and catabolism of the chitin disaccharide chitobiose are encoded by the chb operon. The orphan sensor kinase ChiS is critical for regulation of this locus, however, the mechanisms downstream of ChiS activation that result in expression of the chb operon are poorly understood. Using an unbiased transposon mutant screen, we uncover that the nucleoid occlusion protein SlmA is a regulator of the chb operon. SlmA has not previously been implicated in gene regulation. Also, SlmA is a member of the TetR family of proteins, which are generally transcriptional repressors. In vitro, we find that SlmA binds directly to the chb operon promoter, and in vivo, we show that this interaction is required for transcriptional activation of this locus and for chitobiose utilization. Using point mutations that disrupt distinct functions of SlmA, we find that DNA-binding, but not nucleoid occlusion, is critical for transcriptional activation. This study identifies a novel role for SlmA as a transcriptional regulator in V. cholerae in addition to its established role as a cell division licensing factor. The cholera pathogen Vibrio cholerae is a natural resident of the aquatic environment and causes disease when ingested in the form of contaminated food or drinking water. In the aquatic environment, the shells of marine zooplankton, which are primarily composed of chitin, serve as an important food source for this pathogen. The genes required for the utilization of chitin are tightly regulated in V. cholerae, however, the exact mechanism underlying this regulation is currently unclear. Here, we uncover that a protein involved in regulating cell division is also important for regulating the genes involved in chitin utilization. This is a newly identified property for this cell division protein and the significance of a common regulator for these two disparate activities remains to be understood.
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Affiliation(s)
- Catherine A. Klancher
- Department of Biology, Indiana University, Bloomington, IN, United States of America
| | - Chelsea A. Hayes
- Department of Biology, Indiana University, Bloomington, IN, United States of America
| | - Ankur B. Dalia
- Department of Biology, Indiana University, Bloomington, IN, United States of America
- * E-mail:
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21
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A Shinella β-N-acetylglucosaminidase of glycoside hydrolase family 20 displays novel biochemical and molecular characteristics. Extremophiles 2017; 21:699-709. [DOI: 10.1007/s00792-017-0935-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 04/17/2017] [Indexed: 10/19/2022]
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22
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Zhou J, Song Z, Zhang R, Liu R, Wu Q, Li J, Tang X, Xu B, Ding J, Han N, Huang Z. Distinctive molecular and biochemical characteristics of a glycoside hydrolase family 20 β-N-acetylglucosaminidase and salt tolerance. BMC Biotechnol 2017; 17:37. [PMID: 28399848 PMCID: PMC5387316 DOI: 10.1186/s12896-017-0358-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 04/04/2017] [Indexed: 12/05/2022] Open
Abstract
Background Enzymatic degradation of chitin has attracted substantial attention because chitin is an abundant renewable natural resource, second only to lignocellulose, and because of the promising applications of N-acetylglucosamine in the bioethanol, food and pharmaceutical industries. However, the low activity and poor tolerance to salts and N-acetylglucosamine of most reported β-N-acetylglucosaminidases limit their applications. Mining for novel enzymes from new microorganisms is one way to address this problem. Results A glycoside hydrolase family 20 (GH 20) β-N-acetylglucosaminidase (GlcNAcase) was identified from Microbacterium sp. HJ5 harboured in the saline soil of an abandoned salt mine and was expressed in Escherichia coli. The purified recombinant enzyme showed specific activities of 1773.1 ± 1.1 and 481.4 ± 2.3 μmol min−1 mg−1 towards p-nitrophenyl β-N-acetylglucosaminide and N,N'-diacetyl chitobiose, respectively, a Vmax of 3097 ± 124 μmol min−1 mg−1 towards p-nitrophenyl β-N-acetylglucosaminide and a Ki of 14.59 mM for N-acetylglucosamine inhibition. Most metal ions and chemical reagents at final concentrations of 1.0 and 10.0 mM or 0.5 and 1.0% (v/v) had little or no effect (retaining 84.5 − 131.5% activity) on the enzyme activity. The enzyme can retain more than 53.6% activity and good stability in 3.0–20.0% (w/v) NaCl. Compared with most GlcNAcases, the activity of the enzyme is considerably higher and the tolerance to salts and N-acetylglucosamine is much better. Furthermore, the enzyme had higher proportions of aspartic acid, glutamic acid, alanine, glycine, random coils and negatively charged surfaces but lower proportions of cysteine, lysine, α-helices and positively charged surfaces than its homologs. These molecular characteristics were hypothesised as potential factors in the adaptation for salt tolerance and high activity of the GH 20 GlcNAcase. Conclusions Biochemical characterization revealed that the GlcNAcase had novel salt–GlcNAc tolerance and high activity. These characteristics suggest that the enzyme has versatile potential in biotechnological applications, such as bioconversion of chitin waste and the processing of marine materials and saline foods. Molecular characterization provided an understanding of the molecular–function relationships for the salt tolerance and high activity of the GH 20 GlcNAcase. Electronic supplementary material The online version of this article (doi:10.1186/s12896-017-0358-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Junpei Zhou
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Zhifeng Song
- College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China
| | - Rui Zhang
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Rui Liu
- College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China
| | - Qian Wu
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Junjun Li
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Xianghua Tang
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Bo Xu
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Junmei Ding
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Nanyu Han
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China.,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China.,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China.,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China
| | - Zunxi Huang
- Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Yunnan Normal University, Kunming, 650500, People's Republic of China. .,College of Life Sciences, Yunnan Normal University, No. 768 Juxian Street, Chenggong, Kunming, Yunnan, 650500, People's Republic of China. .,Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment, Yunnan, Kunming, 650500, People's Republic of China. .,Key Laboratory of Enzyme Engineering, Yunnan Normal University, Kunming, 650500, People's Republic of China.
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Abstract
Similar to other genera and species of bacteria, whole genomic sequencing has revolutionized how we think about and address questions of basic Vibrio biology. In this review we examined 36 completely sequenced and annotated members of the Vibrionaceae family, encompassing 12 different species of the genera Vibrio, Aliivibrio, and Photobacterium. We reconstructed the phylogenetic relationships among representatives of this group of bacteria by using three housekeeping genes and 16S rRNA sequences. With an evolutionary framework in place, we describe the occurrence and distribution of primary and alternative sigma factors, global regulators present in all bacteria. Among Vibrio we show that the number and function of many of these sigma factors differs from species to species. We also describe the role of the Vibrio-specific regulator ToxRS in fitness and survival. Examination of the biochemical capabilities was and still is the foundation of classifying and identifying new Vibrio species. Using comparative genomics, we examine the distribution of carbon utilization patterns among Vibrio species as a possible marker for understanding bacteria-host interactions. Finally, we discuss the significant role that horizontal gene transfer, specifically, the distribution and structure of integrons, has played in Vibrio evolution.
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24
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Abstract
Members of the genus Vibrio are known to interact with phyto- and zooplankton in aquatic environments. These interactions have been proven to protect the bacterium from various environmental stresses, serve as a nutrient source, facilitate exchange of DNA, and to serve as vectors of disease transmission. This review highlights the impact of Vibrio-zooplankton interactions at the ecosystem scale and the importance of studies focusing on a wide range of Vibrio-zooplankton interactions. The current knowledge on chitin utilization (i.e., chemotaxis, attachment, and degradation) and the role of these factors in attachment to nonchitinous zooplankton is also presented.
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Molecular Genetics of Beauveria bassiana Infection of Insects. ADVANCES IN GENETICS 2016; 94:165-249. [DOI: 10.1016/bs.adgen.2015.11.003] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Plumbridge J. Regulation of the Utilization of Amino Sugars by Escherichia coli and Bacillus subtilis: Same Genes, Different Control. J Mol Microbiol Biotechnol 2015; 25:154-67. [DOI: 10.1159/000369583] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Amino sugars are dual-purpose compounds in bacteria: they are essential components of the outer wall peptidoglycan (PG) and the outer membrane of Gram-negative bacteria and, in addition, when supplied exogenously their catabolism contributes valuable supplies of energy, carbon and nitrogen to the cell. The enzymes for both the synthesis and degradation of glucosamine (GlcN) and N-acetylglucosamine (GlcNAc) are highly conserved but during evolution have become subject to different regulatory regimes. <i>Escherichia coli</i> grows more rapidly using GlcNAc as a carbon source than with GlcN. On the other hand, <i>Bacillus subtilis,</i> but not other <i>Bacilli</i> tested, grows more efficiently on GlcN than GlcNAc. The more rapid growth on this sugar is associated with the presence of a second, GlcN-specific operon, which is unique to this species. A single locus is associated with the genes for catabolism of GlcNAc and GlcN in <i>E. coli,</i> although they enter the cell via different transporters. In <i>E. coli</i> the amino sugar transport and catabolic genes have also been requisitioned as part of the PG recycling process. Although PG recycling likely occurs in <i>B. subtilis,</i> it appears to have different characteristics.
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Abstract
AbstractChondroitin sulfate (CS) is a ubiquitous component of the cell surface and extracellular matrix of animal tissues. CS chains are covalently bound to a core protein to form a proteoglycan, which is involved in various biological events including cell proliferation, migration, and invasion. Their functions are executed by regulating the activity of bioactive proteins, such as growth factors, morphogens, and cytokines. This review article focuses on the catabolism of CS. This catabolism predominantly occurs in lysosomes to control the activity of CS-proteoglycans. CS chains are fragmented by endo-type glycosidase(s), and the resulting oligosaccharides are then cleaved into monosaccharide moieties from the nonreducing end by exoglycosidases and sulfatases. However, the endo-type glycosidase responsible for the systemic catabolism of CS has not yet been identified. Based on recent advances in studies on hyaluronidases, which were previously considered to be hyaluronan-degrading enzymes, it appears that they recognize CS as their original substrate rather than hyaluronan and acquired hyaluronan-hydrolyzing activity at a relatively late stage of evolution.
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Thi NN, Offen WA, Shareck F, Davies GJ, Doucet N. Structure and Activity of the Streptomyces coelicolor A3(2) β-N-Acetylhexosaminidase Provides Further Insight into GH20 Family Catalysis and Inhibition. Biochemistry 2014; 53:1789-800. [DOI: 10.1021/bi401697j] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Nhung Nguyen Thi
- INRS-Institut
Armand-Frappier, Université du Québec, 531 Boul. des Prairies, Laval, Québec H7V 1B7, Canada
- PROTEO,
the Québec Network for Research on Protein Function, Structure,
and Engineering, 1045
Avenue de la Médecine, Université Laval, Québec, Québec G1V 0A6, Canada
- GRASP,
the Groupe de Recherche Axé sur la Structure des Protéines,
3649 Promenade Sir William Osler, McGill University, Montréal, Québec H3G 0B1, Canada
- Military
Institute of Science and Technology, 17 Hoang Sam, Hanoi, Vietnam
- Vietnam
Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam
| | - Wendy A. Offen
- Structural
Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - François Shareck
- INRS-Institut
Armand-Frappier, Université du Québec, 531 Boul. des Prairies, Laval, Québec H7V 1B7, Canada
| | - Gideon J. Davies
- Structural
Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Nicolas Doucet
- INRS-Institut
Armand-Frappier, Université du Québec, 531 Boul. des Prairies, Laval, Québec H7V 1B7, Canada
- PROTEO,
the Québec Network for Research on Protein Function, Structure,
and Engineering, 1045
Avenue de la Médecine, Université Laval, Québec, Québec G1V 0A6, Canada
- GRASP,
the Groupe de Recherche Axé sur la Structure des Protéines,
3649 Promenade Sir William Osler, McGill University, Montréal, Québec H3G 0B1, Canada
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Katta S, Ankati S, Podile AR. Chitooligosaccharides are converted to N-acetylglucosamine by N-acetyl-β-hexosaminidase from Stenotrophomonas maltophilia. FEMS Microbiol Lett 2013; 348:19-25. [PMID: 23965017 DOI: 10.1111/1574-6968.12237] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 08/18/2013] [Indexed: 11/29/2022] Open
Abstract
The Stenotrophomonas maltophilia k279a (Stm) Hex gene encodes a polypeptide of 785 amino acid residues, with an N-terminal signal peptide. StmHex was cloned without signal peptide and expressed as an 83.6 kDa soluble protein in Escherichia coli BL21 (DE3). Purified StmHex was optimally active at pH 5.0 and 40 °C. The Vmax, Km and kcat/Km for StmHex towards chitin hexamer were 10.55 nkat (mg protein)(-1), 271 μM and 0.246 s(-1) mM(-1), while the kinetic values with chitobiose were 30.65 nkat (mg protein)(-1), 2365 μM and 0.082 s(-1) mM(-1), respectively. Hydrolytic activity on chitooligosaccharides indicated that StmHex was an exo-acting enzyme and yielded N-acetyl-D-glucosamine (GlcNAc) as the final product. StmHex hydrolysed chitooligosaccharides (up to hexamer) into GlcNAc within 60 min, suggesting that this enzyme has potential for use in large-scale production of GlcNAc from chitooligosaccharides.
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Affiliation(s)
- Suma Katta
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, India
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Beier S, Bertilsson S. Bacterial chitin degradation-mechanisms and ecophysiological strategies. Front Microbiol 2013; 4:149. [PMID: 23785358 PMCID: PMC3682446 DOI: 10.3389/fmicb.2013.00149] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 05/28/2013] [Indexed: 11/13/2022] Open
Abstract
Chitin is one the most abundant polymers in nature and interacts with both carbon and nitrogen cycles. Processes controlling chitin degradation are summarized in reviews published some 20 years ago, but the recent use of culture-independent molecular methods has led to a revised understanding of the ecology and biochemistry of this process and the organisms involved. This review summarizes different mechanisms and the principal steps involved in chitin degradation at a molecular level while also discussing the coupling of community composition to measured chitin hydrolysis activities and substrate uptake. Ecological consequences are then highlighted and discussed with a focus on the cross feeding associated with the different habitats that arise because of the need for extracellular hydrolysis of the chitin polymer prior to metabolic use. Principal environmental drivers of chitin degradation are identified which are likely to influence both community composition of chitin degrading bacteria and measured chitin hydrolysis activities.
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Affiliation(s)
- Sara Beier
- Department of Ecology and Genetics, Limnology, Uppsala University Uppsala, Sweden ; Laboratoire d'Océanographie Microbienne, Observatoire Océanologique, UPMC Paris 06, UMR 7621 Banyuls sur mer, France ; Laboratoire d'Océanographie Microbienne, Observatoire Océanologique Centre National de la Recherche Scientifique, UMR 7621 Banyuls sur mer, France
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Bakunina I, Nedashkovskaya O, Balabanova L, Zvyagintseva T, Rasskasov V, Mikhailov V. Comparative analysis of glycoside hydrolases activities from phylogenetically diverse marine bacteria of the genus Arenibacter. Mar Drugs 2013; 11:1977-98. [PMID: 23752354 PMCID: PMC3721217 DOI: 10.3390/md11061977] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 05/22/2013] [Accepted: 05/27/2013] [Indexed: 11/16/2022] Open
Abstract
A total of 16 marine strains belonging to the genus Arenibacter, recovered from diverse microbial communities associated with various marine habitats and collected from different locations, were evaluated in degradation of natural polysaccharides and chromogenic glycosides. Most strains were affiliated with five recognized species, and some presented three new species within the genus Arenibacter. No strains contained enzymes depolymerizing polysaccharides, but synthesized a wide spectrum of glycosidases. Highly active β-N-acetylglucosaminidases and α-N-acetylgalactosaminidases were the main glycosidases for all Arenibacter. The genes, encoding two new members of glycoside hydrolyses (GH) families, 20 and 109, were isolated and characterized from the genomes of Arenibacter latericius. Molecular genetic analysis using glycosidase-specific primers shows the absence of GH27 and GH36 genes. A sequence comparison with functionally-characterized GH20 and GH109 enzymes shows that both sequences are closest to the enzymes of chitinolytic bacteria Vibrio furnissii and Cellulomonas fimi of marine and terrestrial origin, as well as human pathogen Elisabethkingia meningoseptica and simbionts Akkermansia muciniphila, gut and non-gut Bacteroides, respectively. These results revealed that the genus Arenibacter is a highly taxonomic diverse group of microorganisms, which can participate in degradation of natural polymers in marine environments depending on their niche and habitat adaptations. They are new prospective candidates for biotechnological applications due to their production of unique glycosidases.
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Affiliation(s)
- Irina Bakunina
- Laboratory of Enzyme Chemistry, Laboratory of Microbiology and Laboratory of Molecular Biology of G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690022, Russia; E-Mails: (O.N.); (L.B.); (T.Z.); (V.R.); (V.M.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +7-432-231-07-05-3; Fax: +7-432-231-07-05-7
| | - Olga Nedashkovskaya
- Laboratory of Enzyme Chemistry, Laboratory of Microbiology and Laboratory of Molecular Biology of G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690022, Russia; E-Mails: (O.N.); (L.B.); (T.Z.); (V.R.); (V.M.)
| | - Larissa Balabanova
- Laboratory of Enzyme Chemistry, Laboratory of Microbiology and Laboratory of Molecular Biology of G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690022, Russia; E-Mails: (O.N.); (L.B.); (T.Z.); (V.R.); (V.M.)
| | - Tatyana Zvyagintseva
- Laboratory of Enzyme Chemistry, Laboratory of Microbiology and Laboratory of Molecular Biology of G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690022, Russia; E-Mails: (O.N.); (L.B.); (T.Z.); (V.R.); (V.M.)
| | - Valery Rasskasov
- Laboratory of Enzyme Chemistry, Laboratory of Microbiology and Laboratory of Molecular Biology of G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690022, Russia; E-Mails: (O.N.); (L.B.); (T.Z.); (V.R.); (V.M.)
| | - Valery Mikhailov
- Laboratory of Enzyme Chemistry, Laboratory of Microbiology and Laboratory of Molecular Biology of G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690022, Russia; E-Mails: (O.N.); (L.B.); (T.Z.); (V.R.); (V.M.)
- School of Natural Sciences, Far Eastern Federal University, Vladivostok 690091, Russia
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Characterization of genes for chitin catabolism in Haloferax mediterranei. Appl Microbiol Biotechnol 2013; 98:1185-94. [PMID: 23674154 DOI: 10.1007/s00253-013-4969-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 04/27/2013] [Accepted: 04/29/2013] [Indexed: 10/26/2022]
Abstract
Chitin is the second most abundant natural polysaccharide after cellulose. But degradation of chitin has never been reported in haloarchaea. In this study, we revealed that Haloferax mediterranei, a metabolically versatile haloarchaeon, could utilize colloidal or powdered chitin for growth and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) accumulation, and the gene cluster (HFX_5025-5039) for the chitin catabolism pathway was experimentally identified. First, reverse transcription polymerase chain reaction results showed that the expression of the genes encoding the four putative chitinases (ChiAHme, ChiBHme, ChiCHme, and ChiDHme, HFX_5036-5039), the LmbE-like deacetylase (DacHme, HFX_5027), and the glycosidase (GlyAHme, HFX_5029) was induced by colloidal or powdered chitin, and chiA Hme, chiB Hme, and chiC Hme were cotranscribed. Knockout of chiABC Hme or chiD Hme had a significant effect on cell growth and PHBV production when chitin was used as the sole carbon source, and the chiABCD Hme knockout mutant lost the capability to utilize chitin. Knockout of dac Hme or glyA Hme also decreased PHBV accumulation on chitin. These results suggested that ChiABCDHme, DacHme, and GlyAHme were indeed involved in chitin degradation in H. mediterranei. Additionally, the chitinase assay showed that each chitinase possessed hydrolytic activity toward colloidal or powdered chitin, and the major product of colloidal chitin hydrolysis by ChiABCDHme was diacetylchitobiose, which was likely further degraded to monosaccharides by DacHme, GlyAHme, and other related enzymes for both cell growth and PHBV biosynthesis. Taken together, this study revealed the genes and enzymes involved in chitin catabolism in haloarchaea for the first time and indicated the potential of H. mediterranei as a whole-cell biocatalyst in chitin bioconversion.
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Inokuma K, Takano M, Hoshino K. Direct ethanol production from N-acetylglucosamine and chitin substrates by Mucor species. Biochem Eng J 2013. [DOI: 10.1016/j.bej.2012.12.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Rong S, Li DQ, Zhang XY, Li S, Zhu KY, Guo YP, Ma EB, Zhang JZ. RNA interference to reveal roles of β-N-acetylglucosaminidase gene during molting process in Locusta migratoria. INSECT SCIENCE 2013; 20:109-119. [PMID: 23955831 DOI: 10.1111/j.1744-7917.2012.01573.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
β-N-acetylglucosaminidases are crucial enzymes involved in chitin degradation in insects. We identified a β-N-acetylglucosaminidase gene (LmNAG1) from Locusta migratoria. The full-length complementary DNA (cDNA) of LmNAG1 consists of 2 667 nucleotides, including an open reading frame (ORF) of 1 845 nucleotides encoding 614 amino acid residues, and 233- and 589-nucleotide non-coding regions at the 5'- and 3'-ends, respectively. Phylogenetic analysis grouped the cDNA-deduced LmNAG1 protein with the enzymatically characterized β-N-acetylglucosaminidases in group I. Analyses of stage- and tissue-dependent expression patterns of LmNAG1 were carried out by real-time quantitative polymerase chain reaction. Our results showed that LmNAG1 transcript level in the integument was significantly high in the last 2 days of the fourth and fifth instar nymphs. LmNAG1 was highly expressed in foregut and hindgut. RNA interference of LmNAG1 resulted in an effective silence of the gene and a significantly reduced total LmNAG enzyme activity at 48 and 72 h after the injection of LmNAG1 double-stranded RNA (dsRNA). As compared with the control nymphs injected with GFP dsRNA, 50% of the dsLmNAG1-injected nymphs were not able to molt successfully and eventually died. Our results suggest that LmNAG1 plays an essential role in molting process of L. migratoria.
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Affiliation(s)
- Shuo Rong
- Research Institute of Applied Biology, Shanxi University, Taiyuan
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Suginta W, Chumjan W, Mahendran KR, Janning P, Schulte A, Winterhalter M. Molecular uptake of chitooligosaccharides through chitoporin from the marine bacterium Vibrio harveyi. PLoS One 2013; 8:e55126. [PMID: 23383078 PMCID: PMC3558487 DOI: 10.1371/journal.pone.0055126] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 12/18/2012] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Chitin is the most abundant biopolymer in marine ecosystems. However, there is no accumulation of chitin in the ocean-floor sediments, since marine bacteria Vibrios are mainly responsible for a rapid turnover of chitin biomaterials. The catabolic pathway of chitin by Vibrios is a multi-step process that involves chitin attachment and degradation, followed by chitooligosaccharide uptake across the bacterial membranes, and catabolism of the transport products to fructose-6-phosphate, acetate and NH(3). PRINCIPAL FINDINGS This study reports the isolation of the gene corresponding to an outer membrane chitoporin from the genome of Vibrio harveyi. This porin, expressed in E. coli, (so called VhChiP) was found to be a SDS-resistant, heat-sensitive trimer. Immunoblotting using anti-ChiP polyclonal antibody confirmed the expression of the recombinant ChiP, as well as endogenous expression of the native protein in the V. harveyi cells. The specific function of VhChiP was investigated using planar lipid membrane reconstitution technique. VhChiP nicely inserted into artificial membranes and formed stable, trimeric channels with average single conductance of 1.8±0.13 nS. Single channel recordings at microsecond-time resolution resolved translocation of chitooligosaccharides, with the greatest rate being observed for chitohexaose. Liposome swelling assays showed no permeation of other oligosaccharides, including maltose, sucrose, maltopentaose, maltohexaose and raffinose, indicating that VhChiP is a highly-specific channel for chitooligosaccharides. CONCLUSION/SIGNIFICANCE We provide the first evidence that chitoporin from V. harveyi is a chitooligosaccharide specific channel. The results obtained from this study help to establish the fundamental role of VhChiP in the chitin catabolic cascade as the molecular gateway that Vibrios employ for chitooligosaccharide uptake for energy production.
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Affiliation(s)
- Wipa Suginta
- Biochemistry-Electrochemistry Research Unit, Schools of Chemistry and Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand.
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Konno N, Takahashi H, Nakajima M, Takeda T, Sakamoto Y. Characterization of β-N-acetylhexosaminidase (LeHex20A), a member of glycoside hydrolase family 20, from Lentinula edodes (shiitake mushroom). AMB Express 2012; 2:29. [PMID: 22656067 PMCID: PMC3430601 DOI: 10.1186/2191-0855-2-29] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 05/13/2012] [Indexed: 01/29/2023] Open
Abstract
We purified and cloned a β-N-acetylhexosaminidase, LeHex20A, with a molecular mass of 79 kDa from the fruiting body of Lentinula edodes (shiitake mushroom). The gene lehex20a gene had 1,659 nucleotides, encoding 553 amino acid residues. Sequence analysis indicated that LeHex20A belongs to glycoside hydrolase (GH) family 20, and homologues of lehex20a are broadly represented in the genomes of basidiomycetes. Purified LeHex20A hydrolyzed the terminal monosaccharide residues of β-N-acetylgalactosaminides and β-N-acetylglucosaminides, indicating that LeHex20A is a β-N-acetylhexosaminidase classified into EC 3.2.1.52. The maximum LeHex20A activity was observed at pH 4.0 and 50°C. The kinetic constants were estimated using chitooligosaccharides with degree of polymerization 2-6. GH20 β-N-acetylhexosaminidases generally prefer chitobiose among natural substrates. However, LeHex20A had the highest catalytic efficiency (kcat/Km) for chitotetraose, and the Km values for GlcNAc6 were 3.9-fold lower than for chitobiose. Furthermore, the enzyme partially hydrolyzed amorphous chitin polymers. These results indicate that LeHex20A can produce N-acetylglucosamine from long-chain chitomaterials.
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Affiliation(s)
- Naotake Konno
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami-shi, Iwate 024-0003, Japan
| | - Hideyuki Takahashi
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami-shi, Iwate 024-0003, Japan
| | - Masahiro Nakajima
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami-shi, Iwate 024-0003, Japan
| | - Takumi Takeda
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami-shi, Iwate 024-0003, Japan
| | - Yuichi Sakamoto
- Iwate Biotechnology Research Center, 22-174-4 Narita, Kitakami-shi, Iwate 024-0003, Japan
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Huang L, Garbulewska E, Sato K, Kato Y, Nogawa M, Taguchi G, Shimosaka M. Isolation of genes coding for chitin-degrading enzymes in the novel chitinolytic bacterium, Chitiniphilus shinanonensis, and characterization of a gene coding for a family 19 chitinase. J Biosci Bioeng 2012; 113:293-9. [DOI: 10.1016/j.jbiosc.2011.10.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 10/24/2011] [Accepted: 10/25/2011] [Indexed: 10/14/2022]
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Thompson FL, Neto AA, Santos EDO, Izutsu K, Iida T. Effect of N-acetyl-D-glucosamine on gene expression in Vibrio parahaemolyticus. Microbes Environ 2011; 26:61-6. [PMID: 21487204 DOI: 10.1264/jsme2.me10152] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We analyzed the effect of N-acetyl-D-glucosamine (GlcNAc) on gene expression in the marine bacterium Vibrio parahaemolyticus. The total number of genes whose expression was induced and repressed genes in the presence of GlcNAc was 81 and 55, respectively. The induced genes encoded a variety of products, including proteins related to energy metabolism (e.g. GlcNAc and chitin utilization), transport, central metabolism and chemotaxis, hypothetical proteins, mannose-sensitive hemagglutinin pilus (MSHA), and a PilA protein, whereas the repressed genes encoded mainly hypothetical proteins. GlcNAc appears to influence directly or indirectly a variety of cellular processes, including energy metabolism, chitin utilization, competence, biofilm formation and pathogenicity. GlcNAc, one of the most abundant aminosugars in the oceans, is used by V. parahaemolyticus as an energy source and affects the cellular functioning of this marine bacterium.
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Affiliation(s)
- Fabiano L Thompson
- Department of Genetics, Institute of Biology, Federal University of Rio de Janeiro, Brazil.
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Slámová K, Bojarová P, Petrásková L, Křen V. β-N-Acetylhexosaminidase: What's in a name…? Biotechnol Adv 2010; 28:682-93. [DOI: 10.1016/j.biotechadv.2010.04.004] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 04/17/2010] [Accepted: 04/24/2010] [Indexed: 01/28/2023]
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Park J, Kim W, Park Y. Purification and characterization of an exo-type β-N-acetylglucosaminidase from Pseudomonas fluorescens JK-0412. J Appl Microbiol 2010; 110:277-86. [DOI: 10.1111/j.1365-2672.2010.04879.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Suginta W, Chuenark D, Mizuhara M, Fukamizo T. Novel β-N-acetylglucosaminidases from Vibrio harveyi 650: cloning, expression, enzymatic properties, and subsite identification. BMC BIOCHEMISTRY 2010; 11:40. [PMID: 20920218 PMCID: PMC2955587 DOI: 10.1186/1471-2091-11-40] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Accepted: 09/29/2010] [Indexed: 12/16/2022]
Abstract
Background Since chitin is a highly abundant natural biopolymer, many attempts have been made to convert this insoluble polysaccharide into commercially valuable products using chitinases and β-N-acetylglucosaminidases (GlcNAcases). We have previously reported the structure and function of chitinase A from Vibrio harveyi 650. This study t reports the identification of two GlcNAcases from the same organism and their detailed functional characterization. Results The genes encoding two new members of family-20 GlcNAcases were isolated from the genome of V. harveyi 650, cloned and expressed at a high level in E. coli. VhNag1 has a molecular mass of 89 kDa and an optimum pH of 7.5, whereas VhNag2 has a molecular mass of 73 kDa and an optimum pH of 7.0. The recombinant GlcNAcases were found to hydrolyze all the natural substrates, VhNag2 being ten-fold more active than VhNag1. Product analysis by TLC and quantitative HPLC suggested that VhNag2 degraded chitooligosaccharides in a sequential manner, its highest activity being with chitotetraose. Kinetic modeling of the enzymic reaction revealed that binding at subsites (-2) and (+4) had unfavorable (positive) binding free energy changes and that the binding pocket of VhNag2 contains four GlcNAc binding subsites, designated (-1),(+1),(+2), and (+3). Conclusions Two novel GlcNAcases were identified as exolytic enzymes that degraded chitin oligosaccharides, releasing GlcNAc as the end product. In living cells, these intracellular enzymes may work after endolytic chitinases to complete chitin degradation. The availability of the two GlcNAcases, together with the previously-reported chitinase A from the same organism, suggests that a systematic development of the chitin-degrading enzymes may provide a valuable tool in commercial chitin bioconversion.
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Affiliation(s)
- Wipa Suginta
- Biochemistry-Electrochemistry Research Unit, School of Chemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
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Chitin utilization by the insect-transmitted bacterium Xylella fastidiosa. Appl Environ Microbiol 2010; 76:6134-40. [PMID: 20656858 DOI: 10.1128/aem.01036-10] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xylella fastidiosa is an insect-borne bacterium that colonizes xylem vessels of a large number of host plants, including several crops of economic importance. Chitin is a polysaccharide present in the cuticle of leafhopper vectors of X. fastidiosa and may serve as a carbon source for this bacterium. Biological assays showed that X. fastidiosa reached larger populations in the presence of chitin. Additionally, chitin induced phenotypic changes in this bacterium, notably increasing adhesiveness. Quantitative PCR assays indicated transcriptional changes in the presence of chitin, and an enzymatic assay demonstrated chitinolytic activity by X. fastidiosa. An ortholog of the chitinase A gene (chiA) was identified in the X. fastidiosa genome. The in silico analysis revealed that the open reading frame of chiA encodes a protein of 351 amino acids with an estimated molecular mass of 40 kDa. chiA is in a locus that consists of genes implicated in polysaccharide degradation. Moreover, this locus was also found in the genomes of closely related bacteria in the genus Xanthomonas, which are plant but not insect associated. X. fastidiosa degraded chitin when grown on a solid chitin-yeast extract-agar medium and grew in liquid medium with chitin as the sole carbon source; ChiA was also determined to be secreted. The gene encoding ChiA was cloned into Escherichia coli, and endochitinase activity was detected in the transformant, showing that the gene is functional and involved in chitin degradation. The results suggest that X. fastidiosa may use its vectors' foregut surface as a carbon source. In addition, chitin may trigger X. fastidiosa's gene regulation and biofilm formation within vectors. Further work is necessary to characterize the role of chitin and its utilization in X. fastidiosa.
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A reducing-end-acting chitinase from Vibrio proteolyticus belonging to glycoside hydrolase family 19. Appl Microbiol Biotechnol 2008; 78:627-34. [DOI: 10.1007/s00253-008-1352-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 01/03/2008] [Accepted: 01/06/2008] [Indexed: 12/19/2022]
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Genes induced late in infection increase fitness of Vibrio cholerae after release into the environment. Cell Host Microbe 2007; 2:264-77. [PMID: 18005744 DOI: 10.1016/j.chom.2007.09.004] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 08/16/2007] [Accepted: 09/13/2007] [Indexed: 01/12/2023]
Abstract
The facultative pathogen Vibrio cholerae can exist in both the human small bowel and in aquatic environments. While investigation of the infection process has revealed many factors important for pathogenesis, little is known regarding transmission of this or other water-borne pathogens. Using a temporally controlled reporter of transcription, we focus on bacterial gene expression during the late stage of infection and identify a unique class of V. cholerae genes specific to this stage. Mutational analysis revealed limited roles for these genes in infection. However, using a host-to-environment transition assay, we detected roles for six of ten genes examined for the ability of V. cholerae to persist within cholera stool and/or aquatic environments. Furthermore, passage through the intestinal tract was necessary to observe this phenotype. Thus, V. cholerae genes expressed prior to exiting the host intestinal tract are advantageous for subsequent life in aquatic environments.
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Abstract
Vibrionaceae are regarded as important marine chitin degraders, and attachment to chitin regulates important biological functions; yet, the degree of chitin pathway conservation in Vibrionaceae is unknown. Here, a core chitin degradation pathway is proposed based on comparison of 19 Vibrio and Photobacterium genomes with a detailed metabolic map assembled for V. cholerae from published biochemical, genomic, and transcriptomic results. Further, to assess whether chitin degradation is a conserved property of Vibrionaceae, a set of 54 strains from 32 taxa were tested for the ability to grow on various forms of chitin. All strains grew on N-acetylglucosamine (GlcNAc), the monomer of chitin. The majority of isolates grew on alpha (crab shell) and beta (squid pen) chitin and contained chitinase A (chiA) genes. chiA sequencing and phylogenetic analysis suggest that this gene is a good indicator of chitin metabolism but appears subject to horizontal gene transfer and duplication. Overall, chitin metabolism appears to be a core function of Vibrionaceae, but individual pathway components exhibit dynamic evolutionary histories.
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LeCleir GR, Buchan A, Maurer J, Moran MA, Hollibaugh JT. Comparison of chitinolytic enzymes from an alkaline, hypersaline lake and an estuary. Environ Microbiol 2007; 9:197-205. [PMID: 17227424 DOI: 10.1111/j.1462-2920.2006.01128.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We examined the genetic and physiological characteristics of chitin degrading enzymes expressed by fosmids cloned from two strains of chitinolytic gammaproteobacteria isolated from alkaline, hypersaline Mono Lake, California; and from a metagenomic library derived from an estuarine bacterial community (Dean Creek, Sapelo Island, GA, USA). The Mono Lake chitinolytic enzymes presented unique adaptations in terms of halo- and alkalitolerance. The sequence from one of the Mono Lake isolates (strain 12A) was a conventional family 18 glycosyl hydrolase; however, the expressed protein had a novel secondary activity peak at pH 10. We obtained a novel family 20 glycosyl hydrolase sequence from Mono Lake strain AI21. The activity of the expressed protein had a pH optimum of 10, several pH units higher than any other enzyme currently assigned to this family, and the enzyme retained 80% of its activity at pH 11. The enzyme was also halotolerant, retaining activity in salt solutions of up to 225 g l(-1). Sequence analysis indicated a molecular weight of approximately 90 kDa for the protein, and that it contained two active sites. Culture supernatant contained two chitinolytic proteins, 45 and 31 kDa, suggesting possible post-expression modification of the gene product. In contrast, the sequence found in the estuarine metagenomic library and the functional characteristics of the protein expressed from it were those of a conventional family 18 glycosyl hydrolase.
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Affiliation(s)
- Gary R LeCleir
- Department of Marine Sciences, University of Georgia, Athens, GA, USA
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Lin J, Xiao X, Zeng X, Wang F. Expression, characterization and mutagenesis of the gene encoding β-N-acetylglucosaminidase from Aeromonas caviae CB101. Enzyme Microb Technol 2006. [DOI: 10.1016/j.enzmictec.2005.08.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Bruce AF, Gounaris K. Characterisation of a secreted N-acetyl-β-hexosaminidase from Trichinella spiralis. Mol Biochem Parasitol 2006; 145:84-93. [PMID: 16242793 DOI: 10.1016/j.molbiopara.2005.09.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 09/19/2005] [Accepted: 09/21/2005] [Indexed: 11/18/2022]
Abstract
A thorough investigation was conducted for glycoside hydrolase activities in the secreted proteins of Trichinella spiralis. The data demonstrated that the only secreted glycosidase with significant activity was an exo-beta-hexosaminidase with catalysis of the substrates N-acetyl-beta-D-glucosamine, N-acetyl-beta-D-galactosamine and N-acetyl-beta-D-glucosamine-6-sulphate proceeding with an efficiency similar to the human isozyme beta-hexosaminidase A (Hex A). The hydrolysis of N-acetyl-beta-D-glucosamine followed Michaelis-Menten kinetics with a K(m) of 0.187+/-0.025 mM, and catalysis was inhibited competitively by both N-acetyl-beta-d-glucosamine and N-acetyl-beta-D-galactosamine, with K(i) values of 15.75+/-0.99 and 1.17+/-0.24 mM, respectively. The enzyme was maximally active at pH 4.4, had a temperature optimum at 54 degrees C and was thermolabile. We observed no cleavage of N-acetylglucosamine beta1-4 linkages in N-acetylchitooligosaccharides, but significant hydrolysis of N-acetylglucosamine beta1-2 linked to mannose in glycans was detected indicating that the secreted enzyme is linkage specific. The enzyme was partially purified and identified by SDS-PAGE and Western blotting as a protein with an apparent molecular mass of 50 kDa. We established that the protein was glycosylated and showed that the glycan was decorated with tyvelose (3,6-dideoxy-D-arabino-hexose). Matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) analysis demonstrated that the carbohydrate moeity was a tyvelose capped tetra-antennary N-glycan corresponding to the structure Tyv(4)Fuc(5)HexNAc(10)Hex(3). All our studies suggest that this is a novel variant of a secreted N-acetyl-beta-hexosaminidase.
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Affiliation(s)
- Alexandra F Bruce
- Division of Cell and Molecular Biology, Biochemistry Building, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
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Prabhakar V, Sasisekharan R. The biosynthesis and catabolism of galactosaminoglycans. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2006; 53:69-115. [PMID: 17239763 DOI: 10.1016/s1054-3589(05)53005-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Vikas Prabhakar
- Division of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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