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Kaplan JB, Sukhishvili SA, Sailer M, Kridin K, Ramasubbu N. Aggregatibacter actinomycetemcomitans Dispersin B: The Quintessential Antibiofilm Enzyme. Pathogens 2024; 13:668. [PMID: 39204268 PMCID: PMC11357414 DOI: 10.3390/pathogens13080668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2024] [Revised: 07/30/2024] [Accepted: 08/06/2024] [Indexed: 09/03/2024] Open
Abstract
The extracellular matrix of most bacterial biofilms contains polysaccharides, proteins, and nucleic acids. These biopolymers have been shown to mediate fundamental biofilm-related phenotypes including surface attachment, intercellular adhesion, and biocide resistance. Enzymes that degrade polymeric biofilm matrix components, including glycoside hydrolases, proteases, and nucleases, are useful tools for studying the structure and function of biofilm matrix components and are also being investigated as potential antibiofilm agents for clinical use. Dispersin B is a well-studied, broad-spectrum antibiofilm glycoside hydrolase produced by Aggregatibacter actinomycetemcomitans. Dispersin B degrades poly-N-acetylglucosamine, a biofilm matrix polysaccharide that mediates biofilm formation, stress tolerance, and biocide resistance in numerous Gram-negative and Gram-positive pathogens. Dispersin B has been shown to inhibit biofilm and pellicle formation; detach preformed biofilms; disaggregate bacterial flocs; sensitize preformed biofilms to detachment by enzymes, detergents, and metal chelators; and sensitize preformed biofilms to killing by antiseptics, antibiotics, bacteriophages, macrophages, and predatory bacteria. This review summarizes the results of nearly 100 in vitro and in vivo studies that have been carried out on dispersin B since its discovery 20 years ago. These include investigations into the biological function of the enzyme, its structure and mechanism of action, and its in vitro and in vivo antibiofilm activities against numerous bacterial species. Also discussed are potential clinical applications of dispersin B.
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Affiliation(s)
- Jeffrey B. Kaplan
- Laboratory for Skin Research, Institute for Medical Research, Galilee Medical Center, Nahariya 2210001, Israel;
| | - Svetlana A. Sukhishvili
- Department of Materials Science and Engineering, Texas A&M University, College Station, TX 77843, USA;
| | | | - Khalaf Kridin
- Laboratory for Skin Research, Institute for Medical Research, Galilee Medical Center, Nahariya 2210001, Israel;
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed 1311502, Israel
| | - Narayanan Ramasubbu
- Department of Oral Biology, Rutgers School of Dental Medicine, Newark, NJ 07103, USA;
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Mészáros Z, Petrásková L, Kulik N, Pelantová H, Bojarová P, Křen V, Slámová K. Hypertransglycosylating Variants of the GH20 β‐
N
‐Acetylhexosaminidase for the Synthesis of Chitooligomers. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Zuzana Mészáros
- Laboratory of Biotransformation Institute of Microbiology of the Czech Academy of Sciences Vídeňská 1083 Prague 4 CZ 14220 Czech Republic
- Department of Biochemistry University of Chemistry and Technology Prague Technická 6 Prague 6 CZ 16000 Czech Republic
| | - Lucie Petrásková
- Laboratory of Biotransformation Institute of Microbiology of the Czech Academy of Sciences Vídeňská 1083 Prague 4 CZ 14220 Czech Republic
| | - Natalia Kulik
- Laboratory of Structural Biology and Bioinformatics Institute of Microbiology of the Czech Academy of Sciences Zámek 136 Nové Hrady CZ 37333 Czech Republic
| | - Helena Pelantová
- Laboratory of Molecular Structure Characterization Institute of Microbiology of the Czech Academy of Sciences Vídeňská 1083 Prague 4 CZ 14220 Czech Republic
| | - Pavla Bojarová
- Laboratory of Biotransformation Institute of Microbiology of the Czech Academy of Sciences Vídeňská 1083 Prague 4 CZ 14220 Czech Republic
| | - Vladimír Křen
- Laboratory of Biotransformation Institute of Microbiology of the Czech Academy of Sciences Vídeňská 1083 Prague 4 CZ 14220 Czech Republic
| | - Kristýna Slámová
- Laboratory of Biotransformation Institute of Microbiology of the Czech Academy of Sciences Vídeňská 1083 Prague 4 CZ 14220 Czech Republic
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Chen Y, Zhou N, Chen X, Wei G, Zhang A, Chen K, Ouyang P. Characterization of a New Multifunctional GH20 β- N-Acetylglucosaminidase From Chitinibacter sp. GC72 and Its Application in Converting Chitin Into N-Acetyl Glucosamine. Front Microbiol 2022; 13:874908. [PMID: 35620090 PMCID: PMC9129912 DOI: 10.3389/fmicb.2022.874908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 03/24/2022] [Indexed: 11/13/2022] Open
Abstract
In this study, a gene encoding β-N-acetylglucosaminidase, designated NAGaseA, was cloned from Chitinibacter sp. GC72 and subsequently functional expressed in Escherichia coli BL21 (DE3). NAGaseA contains a glycoside hydrolase family 20 catalytic domain that shows low identity with the corresponding domain of the well-characterized NAGases. The recombinant NAGaseA had a molecular mass of 92 kDa. Biochemical characterization of the purified NAGaseA revealed that the optimal reaction condition was at 40°C and pH 6.5, and exhibited great pH stability in the range of pH 6.5-9.5. The V ma x , K m, k cat, and k cat /K m of NAGaseA toward p-nitrophenyl-N-acetyl glucosaminide (pNP-GlcNAc) were 3333.33 μmol min-1 l-1, 39.99 μmol l-1, 4667.07 s-1, and 116.71 ml μmol-1 s-1, respectively. Analysis of the hydrolysis products of N-acetyl chitin oligosaccharides (N-Acetyl COSs) indicated that NAGaseA was capable of converting N-acetyl COSs ((GlcNAc)2-(GlcNAc)6) into GlcNAc with hydrolysis ability order: (GlcNAc)2 > (GlcNAc)3 > (GlcNAc)4 > (GlcNAc)5 > (GlcNAc)6. Moreover, NAGaseA could generate (GlcNAc)3-(GlcNAc)6 from (GlcNAc)2-(GlcNAc)5, respectively. These results showed that NAGaseA is a multifunctional NAGase with transglycosylation activity. In addition, significantly synergistic action was observed between NAGaseA and other sources of chitinases during hydrolysis of colloid chitin. Finally, 0.759, 0.481, and 0.986 g/l of GlcNAc with a purity of 96% were obtained using three different chitinase combinations, which were 1.61-, 2.36-, and 2.69-fold that of the GlcNAc production using the single chitinase. This observation indicated that NAGaseA could be a potential candidate enzyme in commercial GlcNAc production.
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Affiliation(s)
- Yan Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Ning Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Xueman Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Guoguang Wei
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Alei Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, Lianyungang, China
| | - Kequan Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Pingkai Ouyang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
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Prabhuling SH, Makwana P, Pradeep ANR, Vijayan K, Mishra RK. Release of Mediator Enzyme β-Hexosaminidase and Modulated Gene Expression Accompany Hemocyte Degranulation in Response to Parasitism in the Silkworm Bombyx mori. Biochem Genet 2021; 59:997-1017. [PMID: 33616803 DOI: 10.1007/s10528-021-10046-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 02/02/2021] [Indexed: 01/03/2023]
Abstract
In insects infections trigger hemocyte-mediated immune reactions including degranulation by exocytosis; however, involvement of mediator enzymes in degranulation process is unknown in insects. We report here that in silkworm Bombyx mori, infection by endoparasitoid Exorista bombycis and microsporidian Nosema bombycis activated granulation in granulocytes and promoted degranulation of accumulated structured granules. During degranulation the mediator lysosomal enzyme β-hexosaminidase showed increased activity and expression of β-hexosaminidase gene was enhanced. The events were confirmed in vitro after incubation of uninfected hemocytes with E. bombycis larval tissue protein. On infection, cytotoxicity marker enzyme lactate dehydrogenase (LDH) was released from the hemocytes illustrating cell toxicity. Strong positive correlation (R2 = 0.71) between LDH activity and β-hexosaminidase released after the infection showed parasitic-protein-induced hemocyte damage and accompanied release of the enzymes. Expression of β-hexosaminidase gene was enhanced in early stages after infection followed by down regulation. The expression showed positive correlation (R2 = 0.705) with hexosaminidase activity pattern. B. mori hexosaminidase showed 98% amino acid similarity with that of B. mandarina showing origin from same ancestral gene; however, 45-60% varied from other lepidopterans showing diversity. The observation signifies the less known association of hexosaminidase in degranulation of hemocytes induced by parasitic infection in B. mori and its divergence in different species.
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Affiliation(s)
- Shambhavi H Prabhuling
- Seribiotech Research Laboratory, CSB-Kodathi Campus, Carmelaram. P.O, Bangalore, Karnataka, 560035, India
| | - Pooja Makwana
- Seribiotech Research Laboratory, CSB-Kodathi Campus, Carmelaram. P.O, Bangalore, Karnataka, 560035, India.,Central Sericultural Research & Training Institute, Berhampore, West Bengal, India
| | - Appukuttan Nair R Pradeep
- Seribiotech Research Laboratory, CSB-Kodathi Campus, Carmelaram. P.O, Bangalore, Karnataka, 560035, India.
| | | | - Rakesh Kumar Mishra
- Seribiotech Research Laboratory, CSB-Kodathi Campus, Carmelaram. P.O, Bangalore, Karnataka, 560035, India
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Structural insights of the enzymes from the chitin utilization locus of Flavobacterium johnsoniae. Sci Rep 2020; 10:13775. [PMID: 32792608 PMCID: PMC7426924 DOI: 10.1038/s41598-020-70749-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 07/22/2020] [Indexed: 12/17/2022] Open
Abstract
Chitin is one of the most abundant renewable organic materials found on earth. The chitin utilization locus in Flavobacterium johnsoniae, which encodes necessary proteins for complete enzymatic depolymerization of crystalline chitin, has recently been characterized but no detailed structural information on the enzymes was provided. Here we present protein structures of the F. johnsoniae chitobiase (FjGH20) and chitinase B (FjChiB). FjGH20 is a multi-domain enzyme with a helical domain not before observed in other chitobiases and a domain organization reminiscent of GH84 (β-N-acetylglucosaminidase) family members. The structure of FjChiB reveals that the protein lacks loops and regions associated with exo-acting activity in other chitinases and instead has a more solvent accessible substrate binding cleft, which is consistent with its endo-chitinase activity. Additionally, small angle X-ray scattering data were collected for the internal 70 kDa region that connects the N- and C-terminal chitinase domains of the unique 158 kDa multi-domain chitinase A (FjChiA). The resulting model of the molecular envelope supports bioinformatic predictions of the region comprising six domains, each with similarities to either Fn3-like or Ig-like domains. Taken together, the results provide insights into chitin utilization by F. johnsoniae and reveal structural diversity in bacterial chitin metabolism.
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Zhang A, Mo X, Zhou N, Wang Y, Wei G, Chen J, Chen K, Ouyang P. A novel bacterial β- N-acetyl glucosaminidase from Chitinolyticbacter meiyuanensis possessing transglycosylation and reverse hydrolysis activities. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:115. [PMID: 32612678 PMCID: PMC7324980 DOI: 10.1186/s13068-020-01754-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 06/20/2020] [Indexed: 05/31/2023]
Abstract
BACKGROUND N-Acetyl glucosamine (GlcNAc) and N-Acetyl chitooligosaccharides (N-Acetyl COSs) exhibit many biological activities, and have been widely used in the pharmaceutical, agriculture, food, and chemical industries. Particularly, higher N-Acetyl COSs with degree of polymerization from 4 to 7 ((GlcNAc)4-(GlcNAc)7) show good antitumor and antimicrobial activity, as well as possessing strong stimulating activity toward natural killer cells. Thus, it is of great significance to discover a β-N-acetyl glucosaminidase (NAGase) that can not only produce GlcNAc, but also synthesize N-Acetyl COSs. RESULTS The gene encoding the novel β-N-acetyl glucosaminidase, designated CmNAGase, was cloned from Chitinolyticbacter meiyuanensis SYBC-H1. The deduced amino acid sequence of CmNAGase contains a glycoside hydrolase family 20 catalytic module that shows low identity (12-35%) with the corresponding domain of most well-characterized NAGases. The CmNAGase gene was highly expressed with an active form in Escherichia coli BL21 (DE3) cells. The specific activity of purified CmNAGase toward p-nitrophenyl-N-acetyl glucosaminide (pNP-GlcNAc) was 4878.6 U/mg of protein. CmNAGase had a molecular mass of 92 kDa, and its optimum activity was at pH 5.4 and 40 °C. The V max, K m, K cat, and K cat/K m of CmNAGase for pNP-GlcNAc were 16,666.67 μmol min-1 mg-1, 0.50 μmol mL-1, 25,555.56 s-1, and 51,111.12 mL μmol-1 s-1, respectively. Analysis of the hydrolysis products of N-Acetyl COSs and colloidal chitin revealed that CmNAGase is a typical exo-acting NAGase. Particularly, CmNAGase can synthesize higher N-Acetyl COSs ((GlcNAc)3-(GlcNAc)7) from (GlcNAc)2-(GlcNAc)6, respectively, showed that it possesses transglycosylation activity. In addition, CmNAGase also has reverse hydrolysis activity toward GlcNAc, synthesizing various linked GlcNAc dimers. CONCLUSIONS The observations recorded in this study that CmNAGase is a novel NAGase with exo-acting, transglycosylation, and reverse hydrolysis activities, suggest a possible application in the production of GlcNAc or higher N-Acetyl COSs.
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Affiliation(s)
- Alei Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Xiaofang Mo
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Ning Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Yingying Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Guoguang Wei
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Jie Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Kequan Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
| | - Pingkai Ouyang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211800 People’s Republic of China
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Lyu Z, Chen J, Li Z, Cheng J, Wang C, Lin T. Knockdown of β-N-acetylglucosaminidase gene disrupts molting process in Heortia vitessoides Moore. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2019; 101:e21561. [PMID: 31218752 DOI: 10.1002/arch.21561] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 05/08/2019] [Accepted: 05/14/2019] [Indexed: 06/09/2023]
Abstract
β-N-acetylglucosaminidase (NAG) is a key enzyme in insect chitin metabolism and plays an important role in many physiological activities of insects. The HvNAG1 gene was identified from the Heortia vitessoides Moore (Lepidoptera: Crambidae) cDNA library and its expression patterns were determined using quantitative real-time polymerase chain reaction. The results indicated that HvNAG1 mRNA levels were high in the midgut and before molting, and 20E could induce its expression. Subsequently, the HvNAG1 gene was knocked down via RNA interference to identify its functions. We found that 3 μg of dsNAG1 resulted in optimal interference at 48 and 72 hr after injection, causing a decrease in NAG1 protein content, which resulted in abnormal or lethal phenotypes, and a sharp decrease in the survival rate. These results indicate that HvNAG1 plays a key role in the molting process of H. vitessoides. However, the silencing of HvNAG1 had no significant effect on the chitin metabolism-related genes tested in this study. Our present study provides a reference for further research on the utility of key genes involved in the chitin metabolic pathway in the insect molting process.
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Affiliation(s)
- Zihao Lyu
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Jingxiang Chen
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Zhixing Li
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Jie Cheng
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Chunyan Wang
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Tong Lin
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
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Molecular engineering of chitinase from Bacillus sp. DAU101 for enzymatic production of chitooligosaccharides. Enzyme Microb Technol 2019; 124:54-62. [DOI: 10.1016/j.enzmictec.2019.01.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 01/21/2019] [Accepted: 01/29/2019] [Indexed: 01/20/2023]
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Chen X, Wang J, Liu M, Yang W, Wang Y, Tang R, Zhang M. Crystallographic evidence for substrate-assisted catalysis of β-N-acetylhexosaminidas from Akkermansia muciniphila. Biochem Biophys Res Commun 2019; 511:833-839. [PMID: 30846208 DOI: 10.1016/j.bbrc.2019.02.074] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 02/14/2019] [Indexed: 12/21/2022]
Abstract
β-N-acetylhexosaminidases from Akkermansia muciniphila was reported to perform the crystal structure with GlcNAc complex, which proved to be the substrate of Am2301. Domain II of Am2301 is consisted of amino acid residues 111-489 and is folded as a (β/α)8 barrel with the active site combined of the glycosyl hydrolases. Crystallographic evidence showed that Asp-278 and Glu-279 could be the catalytic site and Tyr-373 may plays a role on binding the substrate. Moreover, Am2301 prefers to bind Zn ion, which similar to other GH 20 family. Enzyme activity and kinetic parameters of wild-type Am2301 and mutants proved that Asp-278 and Glu-279 are the catalytic sites and they play a critical role on the catalytic process. Overall, our results demonstrate that Am2301 and its complex with GlcNAC provide obvious structural evidence for substrate-assisted catalysis. Obviously, this expands our understanding on the mode of substrate-assisted reaction for this enzyme family in Akkermansia muciniphila.
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Affiliation(s)
- Xi Chen
- School of Life Sciences, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China; Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China; Department of Biological and Food Engineering, Bozhou University, 2266 Tangwang Road, Bozhou, Anhui, China
| | - Junchao Wang
- School of Life Sciences, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China; Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China
| | - Mingjie Liu
- School of Life Sciences, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China; Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China
| | - Wenyi Yang
- School of Life Sciences, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China; Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China
| | - Yongzhong Wang
- School of Life Sciences, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China; Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China
| | - Rupei Tang
- School of Life Sciences, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China.
| | - Min Zhang
- School of Life Sciences, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China; Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, 111 Jiulong Road, Hefei, Anhui, 230601, China.
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Jamek SB, Muschiol J, Holck J, Zeuner B, Busk PK, Mikkelsen JD, Meyer AS. Loop Protein Engineering for Improved Transglycosylation Activity of a β‐
N
‐Acetylhexosaminidase. Chembiochem 2018; 19:1858-1865. [DOI: 10.1002/cbic.201800181] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Indexed: 01/17/2023]
Affiliation(s)
- Shariza B. Jamek
- Center for Bioprocess EngineeringDepartment of Chemical and Biochemical EngineeringTechnical University of Denmark Søltofts Plads Building 229 2800 Kongens Lyngby Denmark
- Faculty of Chemical and Natural Resources EngineeringUniversity Malaysia Pahang Lebuhraya Tun Razak 26300 Gambang, Kuantan, Pahang Malaysia
| | - Jan Muschiol
- Center for Bioprocess EngineeringDepartment of Chemical and Biochemical EngineeringTechnical University of Denmark Søltofts Plads Building 229 2800 Kongens Lyngby Denmark
| | - Jesper Holck
- Center for Bioprocess EngineeringDepartment of Chemical and Biochemical EngineeringTechnical University of Denmark Søltofts Plads Building 229 2800 Kongens Lyngby Denmark
| | - Birgitte Zeuner
- Center for Bioprocess EngineeringDepartment of Chemical and Biochemical EngineeringTechnical University of Denmark Søltofts Plads Building 229 2800 Kongens Lyngby Denmark
| | - Peter K. Busk
- Center for Bioprocess EngineeringDepartment of Chemical and Biochemical EngineeringTechnical University of Denmark Søltofts Plads Building 229 2800 Kongens Lyngby Denmark
| | - Jørn D. Mikkelsen
- Center for Bioprocess EngineeringDepartment of Chemical and Biochemical EngineeringTechnical University of Denmark Søltofts Plads Building 229 2800 Kongens Lyngby Denmark
| | - Anne S. Meyer
- Center for Bioprocess EngineeringDepartment of Chemical and Biochemical EngineeringTechnical University of Denmark Søltofts Plads Building 229 2800 Kongens Lyngby Denmark
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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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12
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Molecular Insight into Evolution of Symbiosis between Breast-Fed Infants and a Member of the Human Gut Microbiome Bifidobacterium longum. Cell Chem Biol 2017; 24:515-524.e5. [PMID: 28392148 DOI: 10.1016/j.chembiol.2017.03.012] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/13/2017] [Accepted: 03/13/2017] [Indexed: 12/23/2022]
Abstract
Breast-fed infants generally have a bifidobacteria-rich microbiota with recent studies indicating that human milk oligosaccharides (HMOs) selectively promote bifidobacterial growth. Bifidobacterium bifidum possesses a glycoside hydrolase family 20 lacto-N-biosidase for liberating lacto-N-biose I from lacto-N-tetraose, an abundant HMO unique to human milk, while Bifidobacterium longum subsp. longum has a non-classified enzyme (LnbX). Here, we determined the crystal structure of the catalytic domain of LnbX and provide evidence for creation of a novel glycoside hydrolase family, GH136. The structure, in combination with inhibition and mutation studies, provides insight into the molecular mechanism and broader substrate specificity of this enzyme. Moreover, through genetic studies, we show that lnbX is indispensable for B. longum growth on lacto-N-tetraose and is a key genetic factor for persistence in the gut of breast-fed infants. Overall, this study reveals possible evolutionary routes for the emergence of symbiosis between humans and bifidobacterial species in the infant gut.
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Meekrathok P, Suginta W. Probing the Catalytic Mechanism of Vibrio harveyi GH20 β-N-Acetylglucosaminidase by Chemical Rescue. PLoS One 2016; 11:e0149228. [PMID: 26870945 PMCID: PMC4752478 DOI: 10.1371/journal.pone.0149228] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Accepted: 01/28/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Vibrio harveyi GH20 β-N-acetylglucosaminidase (VhGlcNAcase) is a chitinolytic enzyme responsible for the successive degradation of chitin fragments to GlcNAc monomers, activating the onset of the chitin catabolic cascade in marine Vibrios. METHODS Two invariant acidic pairs (Asp303-Asp304 and Asp437-Glu438) of VhGlcNAcase were mutated using a site-directed mutagenesis strategy. The effects of these mutations were examined and the catalytic roles of these active-site residues were elucidated using a chemical rescue approach. Enhancement of the enzymic activity of the VhGlcNAcase mutants was evaluated by a colorimetric assay using pNP-GlcNAc as substrate. RESULTS Substitution of Asp303, Asp304, Asp437 or Glu438 with Ala/Asn/Gln produced a dramatic loss of the GlcNAcase activity. However, the activity of the inactive D437A mutant was recovered in the presence of sodium formate. Our kinetic data suggest that formate ion plays a nucleophilic role by mimicking the β-COO-side chain of Asp437, thereby stabilizing the reaction intermediate during both the glycosylation and the deglycosylation steps. CONCLUSIONS Chemical rescue of the inactive D437A mutant of VhGlcNAcase by an added nucleophile helped to identify Asp437 as the catalytic nucleophile/base, and hence its acidic partner Glu438 as the catalytic proton donor/acceptor. GENERAL SIGNIFICANCE Identification of the catalytic nucleophile of VhGlcNAcases supports the proposal of a substrate-assisted mechanism of GH20 GlcNAcases, requiring the catalytic pair Asp437-Glu438 for catalysis. The results suggest the mechanistic basis of the participation of β-N-acetylglucosaminidase in the chitin catabolic pathway of marine Vibrios.
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Affiliation(s)
- Piyanat Meekrathok
- Biochemistry-Electrochemistry Research Unit and School of Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Wipa Suginta
- Biochemistry-Electrochemistry Research Unit and School of Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
- Center of Excellence in Advanced Functional Materials, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
- * E-mail:
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14
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Robb M, Robb CS, Higgins MA, Hobbs JK, Paton JC, Boraston AB. A Second β-Hexosaminidase Encoded in the Streptococcus pneumoniae Genome Provides an Expanded Biochemical Ability to Degrade Host Glycans. J Biol Chem 2015; 290:30888-900. [PMID: 26491009 DOI: 10.1074/jbc.m115.688630] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Indexed: 12/19/2022] Open
Abstract
An important facet of the interaction between the pathogen Streptococcus pneumoniae (pneumococcus) and its human host is the ability of this bacterium to process host glycans. To achieve cleavage of the glycosidic bonds in host glycans, S. pneumoniae deploys a wide array of glycoside hydrolases. Here, we identify and characterize a new family 20 glycoside hydrolase, GH20C, from S. pneumoniae. Recombinant GH20C possessed the ability to hydrolyze the β-linkages joining either N-acetylglucosamine or N-acetylgalactosamine to a wide variety of aglycon residues, thus revealing this enzyme to be a generalist N-acetylhexosaminidase in vitro. X-ray crystal structures were determined for GH20C in a ligand-free form, in complex with the N-acetylglucosamine and N-acetylgalactosamine products of catalysis and in complex with both gluco- and galacto-configured inhibitors O-(2-acetamido-2-deoxy-D-glucopyranosylidene)amino N-phenyl carbamate (PUGNAc), O-(2-acetamido-2-deoxy-D-galactopyranosylidene)amino N-phenyl carbamate (GalPUGNAc), N-acetyl-D-glucosamine-thiazoline (NGT), and N-acetyl-D-galactosamine-thiazoline (GalNGT) at resolutions from 1.84 to 2.7 Å. These structures showed N-acetylglucosamine and N-acetylgalactosamine to be recognized via identical sets of molecular interactions. Although the same sets of interaction were maintained with the gluco- and galacto-configured inhibitors, the inhibition constants suggested preferred recognition of the axial O4 when an aglycon moiety was present (Ki for PUGNAc > GalPUGNAc) but preferred recognition of an equatorial O4 when the aglycon was absent (Ki for GalNGT > NGT). Overall, this study reveals GH20C to be another tool that is unique in the arsenal of S. pneumoniae and that it may implement the effort of the bacterium to utilize and/or destroy the wide array of host glycans that it may encounter.
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Affiliation(s)
- Melissa Robb
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 3P6 and
| | - Craig S Robb
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 3P6 and
| | - Melanie A Higgins
- the Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, South Australia 5005, Australia
| | - Joanne K Hobbs
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 3P6 and
| | - James C Paton
- the Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, South Australia 5005, Australia
| | - Alisdair B Boraston
- From the Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8W 3P6 and
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15
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Val-Cid C, Biarnés X, Faijes M, Planas A. Structural-Functional Analysis Reveals a Specific Domain Organization in Family GH20 Hexosaminidases. PLoS One 2015; 10:e0128075. [PMID: 26024355 PMCID: PMC4449183 DOI: 10.1371/journal.pone.0128075] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 04/23/2015] [Indexed: 12/20/2022] Open
Abstract
Hexosaminidases are involved in important biological processes catalyzing the hydrolysis of N-acetyl-hexosaminyl residues in glycosaminoglycans and glycoconjugates. The GH20 enzymes present diverse domain organizations for which we propose two minimal model architectures: Model A containing at least a non-catalytic GH20b domain and the catalytic one (GH20) always accompanied with an extra α-helix (GH20b-GH20-α), and Model B with only the catalytic GH20 domain. The large Bifidobacterium bifidum lacto-N-biosidase was used as a model protein to evaluate the minimal functional unit due to its interest and structural complexity. By expressing different truncated forms of this enzyme, we show that Model A architectures cannot be reduced to Model B. In particular, there are two structural requirements general to GH20 enzymes with Model A architecture. First, the non-catalytic domain GH20b at the N-terminus of the catalytic GH20 domain is required for expression and seems to stabilize it. Second, the substrate-binding cavity at the GH20 domain always involves a remote element provided by a long loop from the catalytic domain itself or, when this loop is short, by an element from another domain of the multidomain structure or from the dimeric partner. Particularly, the lacto-N-biosidase requires GH20b and the lectin-like domain at the N- and C-termini of the catalytic GH20 domain to be fully soluble and functional. The lectin domain provides this remote element to the active site. We demonstrate restoration of activity of the inactive GH20b-GH20-α construct (model A architecture) by a complementation assay with the lectin-like domain. The engineering of minimal functional units of multidomain GH20 enzymes must consider these structural requirements.
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Affiliation(s)
- Cristina Val-Cid
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, Barcelona, Spain
| | - Xevi Biarnés
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, Barcelona, Spain
| | - Magda Faijes
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, Barcelona, Spain
| | - Antoni Planas
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, Barcelona, Spain
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16
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Meekrathok P, Bürger M, Porfetye AT, Vetter IR, Suginta W. Expression, purification, crystallization and preliminary crystallographic analysis of a GH20 β-N-acetylglucosaminidase from the marine bacterium Vibrio harveyi. Acta Crystallogr F Struct Biol Commun 2015; 71:427-33. [PMID: 25849504 PMCID: PMC4388178 DOI: 10.1107/s2053230x1500415x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 02/27/2015] [Indexed: 11/10/2022] Open
Abstract
Vibrio harveyi β-N-acetylglucosaminidase (VhGlcNAcase) is a new member of the GH20 glycoside hydrolase family responsible for the complete degradation of chitin fragments, with N-acetylglucosamine (GlcNAc) monomers as the final products. In this study, the crystallization and preliminary crystallographic data of wild-type VhGlcNAcase and its catalytically inactive mutant D437A in the absence and the presence of substrate are reported. Crystals of wild-type VhGlcNAcase were grown in 0.1 M sodium acetate pH 4.6, 1.4 M sodium malonate, while crystals of the D437A mutant were obtained in 0.1 M bis-tris pH 7.5, 0.1 M sodium acetate, 20% PEG 3350. X-ray data from the wild-type and the mutant crystals were collected at a synchrotron-radiation light source and were complete to a resolution of 2.5 Å. All crystals were composed of the same type of dimer, with the substrate N,N'-diacetylglucosamine (GlcNAc₂ or diNAG) used for soaking was cleaved by the active enzyme, leaving only a single GlcNAc molecule bound to the protein.
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Affiliation(s)
- Piyanat Meekrathok
- Biochemistry–Electrochemistry Research Unit, School of Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Marco Bürger
- Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | | | - Ingrid R. Vetter
- Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Wipa Suginta
- Biochemistry–Electrochemistry Research Unit, School of Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
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17
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Hattie M, Ito T, Debowski AW, Arakawa T, Katayama T, Yamamoto K, Fushinobu S, Stubbs KA. Gaining insight into the catalysis by GH20 lacto-N-biosidase using small molecule inhibitors and structural analysis. Chem Commun (Camb) 2015; 51:15008-11. [DOI: 10.1039/c5cc05494j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Synthesis and structural analysis of rationally developed inhibitors.
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Affiliation(s)
- Mitchell Hattie
- School of Chemistry and Biochemistry
- The University of Western Australia
- Crawley
- Australia
| | - Tasuku Ito
- National Food Research Institute
- National Agriculture and Food Research Organization
- Tsukuba
- Japan
| | - Aleksandra W. Debowski
- School of Chemistry and Biochemistry
- The University of Western Australia
- Crawley
- Australia
- School of Pathology and Laboratory Medicine
| | - Takatoshi Arakawa
- Department of Biotechnology
- The University of Tokyo
- Tokyo 113-8657
- Japan
| | - Takane Katayama
- Graduate School of Biostudies
- Kyoto University
- Kyoto 606-8502
- Japan
| | - Kenji Yamamoto
- Research Institute for Bioresources and Biotechnology
- Ishikawa Prefectural University
- Nonoichi
- Japan
| | - Shinya Fushinobu
- Department of Biotechnology
- The University of Tokyo
- Tokyo 113-8657
- Japan
| | - Keith A. Stubbs
- School of Chemistry and Biochemistry
- The University of Western Australia
- Crawley
- Australia
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18
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Molecular phylogeny and predicted 3D structure of plant beta-D-N-acetylhexosaminidase. ScientificWorldJournal 2014; 2014:186029. [PMID: 25165734 PMCID: PMC4129151 DOI: 10.1155/2014/186029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 06/14/2014] [Accepted: 06/21/2014] [Indexed: 11/21/2022] Open
Abstract
beta-D-N-Acetylhexosaminidase, a family 20 glycosyl hydrolase, catalyzes the removal of β-1,4-linked N-acetylhexosamine residues from oligosaccharides and their conjugates. We constructed phylogenetic tree of β-hexosaminidases to analyze the evolutionary history and predicted functions of plant hexosaminidases. Phylogenetic analysis reveals the complex history of evolution of plant β-hexosaminidase that can be described by gene duplication events. The 3D structure of tomato β-hexosaminidase (β-Hex-Sl) was predicted by homology modeling using 1now as a template. Structural conformity studies of the best fit model showed that more than 98% of the residues lie inside the favoured and allowed regions where only 0.9% lie in the unfavourable region. Predicted 3D structure contains 531 amino acids residues with glycosyl hydrolase20b domain-I and glycosyl hydrolase20 superfamily domain-II including the (β/α)8 barrel in the central part. The α and β contents of the modeled structure were found to be 33.3% and 12.2%, respectively. Eleven amino acids were found to be involved in ligand-binding site; Asp(330) and Glu(331) could play important roles in enzyme-catalyzed reactions. The predicted model provides a structural framework that can act as a guide to develop a hypothesis for β-Hex-Sl mutagenesis experiments for exploring the functions of this class of enzymes in plant kingdom.
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19
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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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20
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Yu WL, Jiang YL, Pikis A, Cheng W, Bai XH, Ren YM, Thompson J, Zhou CZ, Chen Y. Structural insights into the substrate specificity of a 6-phospho-β-glucosidase BglA-2 from Streptococcus pneumoniae TIGR4. J Biol Chem 2013; 288:14949-58. [PMID: 23580646 DOI: 10.1074/jbc.m113.454751] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The 6-phospho-β-glucosidase BglA-2 (EC 3.2.1.86) from glycoside hydrolase family 1 (GH-1) catalyzes the hydrolysis of β-1,4-linked cellobiose 6-phosphate (cellobiose-6'P) to yield glucose and glucose 6-phosphate. Both reaction products are further metabolized by the energy-generating glycolytic pathway. Here, we present the first crystal structures of the apo and complex forms of BglA-2 with thiocellobiose-6'P (a non-metabolizable analog of cellobiose-6'P) at 2.0 and 2.4 Å resolution, respectively. Similar to other GH-1 enzymes, the overall structure of BglA-2 from Streptococcus pneumoniae adopts a typical (β/α)8 TIM-barrel, with the active site located at the center of the convex surface of the β-barrel. Structural analyses, in combination with enzymatic data obtained from site-directed mutant proteins, suggest that three aromatic residues, Tyr(126), Tyr(303), and Trp(338), at subsite +1 of BglA-2 determine substrate specificity with respect to 1,4-linked 6-phospho-β-glucosides. Moreover, three additional residues, Ser(424), Lys(430), and Tyr(432) of BglA-2, were found to play important roles in the hydrolytic selectivity toward phosphorylated rather than non-phosphorylated compounds. Comparative structural analysis suggests that a tryptophan versus a methionine/alanine residue at subsite -1 may contribute to the catalytic and substrate selectivity with respect to structurally similar 6-phospho-β-galactosidases and 6-phospho-β-glucosidases assigned to the GH-1 family.
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Affiliation(s)
- Wei-Li Yu
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei Anhui 230027, China
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21
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Ito T, Katayama T, Hattie M, Sakurama H, Wada J, Suzuki R, Ashida H, Wakagi T, Yamamoto K, Stubbs KA, Fushinobu S. Crystal structures of a glycoside hydrolase family 20 lacto-N-biosidase from Bifidobacterium bifidum. J Biol Chem 2013; 288:11795-806. [PMID: 23479733 DOI: 10.1074/jbc.m112.420109] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Human milk oligosaccharides contain a large variety of oligosaccharides, of which lacto-N-biose I (Gal-β1,3-GlcNAc; LNB) predominates as a major core structure. A unique metabolic pathway specific for LNB has recently been identified in the human commensal bifidobacteria. Several strains of infant gut-associated bifidobacteria possess lacto-N-biosidase, a membrane-anchored extracellular enzyme, that liberates LNB from the nonreducing end of human milk oligosaccharides and plays a key role in the metabolic pathway of these compounds. Lacto-N-biosidase belongs to the glycoside hydrolase family 20, and its reaction proceeds via a substrate-assisted catalytic mechanism. Several crystal structures of GH20 β-N-acetylhexosaminidases, which release monosaccharide GlcNAc from its substrate, have been determined, but to date, a structure of lacto-N-biosidase is unknown. Here, we have determined the first three-dimensional structures of lacto-N-biosidase from Bifidobacterium bifidum JCM1254 in complex with LNB and LNB-thiazoline (Gal-β1,3-GlcNAc-thiazoline) at 1.8-Å resolution. Lacto-N-biosidase consists of three domains, and the C-terminal domain has a unique β-trefoil-like fold. Compared with other β-N-acetylhexosaminidases, lacto-N-biosidase has a wide substrate-binding pocket with a -2 subsite specific for β-1,3-linked Gal, and the residues responsible for Gal recognition were identified. The bound ligands are recognized by extensive hydrogen bonds at all of their hydroxyls consistent with the enzyme's strict substrate specificity for the LNB moiety. The GlcNAc sugar ring of LNB is in a distorted conformation near (4)E, whereas that of LNB-thiazoline is in a (4)C1 conformation. A possible conformational pathway for the lacto-N-biosidase reaction is discussed.
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Affiliation(s)
- Tasuku Ito
- Department of Biotechnology, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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22
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Vaaje-Kolstad G, Horn SJ, Sørlie M, Eijsink VGH. The chitinolytic machinery ofSerratia marcescens- a model system for enzymatic degradation of recalcitrant polysaccharides. FEBS J 2013; 280:3028-49. [DOI: 10.1111/febs.12181] [Citation(s) in RCA: 210] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 01/30/2013] [Accepted: 02/05/2013] [Indexed: 01/13/2023]
Affiliation(s)
- Gustav Vaaje-Kolstad
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
| | - Svein J. Horn
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
| | - Morten Sørlie
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
| | - Vincent G. H. Eijsink
- Department of Chemistry; Biotechnology and Food Science; Norwegian University of Life Sciences; Ås; Norway
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23
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Liu T, Wu Q, Liu L, Yang Q. Elimination of substrate inhibition of a β-N-acetyl-d-hexosaminidase by single site mutation. Process Biochem 2013. [DOI: 10.1016/j.procbio.2012.11.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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24
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Wang Y, Liu T, Yang Q, Li Z, Qian X. A Modeling Study for Structure Features of β-N-acetyl-D-hexosaminidase from Ostrinia furnacalis and its Novel Inhibitor Allosamidin: Species Selectivity and Multi-Target Characteristics. Chem Biol Drug Des 2012; 79:572-82. [DOI: 10.1111/j.1747-0285.2011.01301.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Jiang YL, Yu WL, Zhang JW, Frolet C, Di Guilmi AM, Zhou CZ, Vernet T, Chen Y. Structural basis for the substrate specificity of a novel β-N-acetylhexosaminidase StrH protein from Streptococcus pneumoniae R6. J Biol Chem 2011; 286:43004-12. [PMID: 22013074 PMCID: PMC3234876 DOI: 10.1074/jbc.m111.256578] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Revised: 10/05/2011] [Indexed: 11/06/2022] Open
Abstract
The β-N-acetylhexosaminidase (EC 3.2.1.52) from glycoside hydrolase family 20 (GH20) catalyzes the hydrolysis of the β-N-acetylglucosamine (NAG) group from the nonreducing end of various glycoconjugates. The putative surface-exposed N-acetylhexosaminidase StrH/Spr0057 from Streptococcus pneumoniae R6 was proved to contribute to the virulence by removal of β(1,2)-linked NAG on host defense molecules following the cleavage of sialic acid and galactose by neuraminidase and β-galactosidase, respectively. StrH is the only reported GH20 enzyme that contains a tandem repeat of two 53% sequence-identical catalytic domains (designated as GH20-1 and GH20-2, respectively). Here, we present the 2.1 Å crystal structure of the N-terminal domain of StrH (residues Glu-175 to Lys-642) complexed with NAG. It adopts an overall structure similar to other GH20 enzymes: a (β/α)(8) TIM barrel with the active site residing at the center of the β-barrel convex side. The kinetic investigation using 4-nitrophenyl N-acetyl-β-d-glucosaminide as the substrate demonstrated that GH20-1 had an enzymatic activity (k(cat)/K(m)) of one-fourth compared with GH20-2. The lower activity of GH20-1 could be attributed to the substitution of active site Cys-469 of GH20-1 to the counterpart Tyr-903 of GH20-2. A complex model of NAGβ(1,2)Man at the active site of GH20-1 combined with activity assays of the corresponding site-directed mutants characterized two key residues Trp-443 and Tyr-482 at subsite +1 of GH20-1 (Trp-876 and Tyr-914 of GH20-2) that might determine the β(1,2) substrate specificity. Taken together, these findings shed light on the mechanism of catalytic specificity toward the β(1,2)-linked β-N-acetylglucosides.
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Affiliation(s)
- Yong-Liang Jiang
- From the Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China and
| | - Wei-Li Yu
- From the Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China and
| | - Jun-Wei Zhang
- From the Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China and
| | - Cecile Frolet
- the Laboratoire d'Ingénierie des Macromolécules, Institut de Biologie Structurale Jean-Pierre Ebel, 38027 Grenoble, France
| | - Anne-Marie Di Guilmi
- the Laboratoire d'Ingénierie des Macromolécules, Institut de Biologie Structurale Jean-Pierre Ebel, 38027 Grenoble, France
| | - Cong-Zhao Zhou
- From the Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China and
| | - Thierry Vernet
- the Laboratoire d'Ingénierie des Macromolécules, Institut de Biologie Structurale Jean-Pierre Ebel, 38027 Grenoble, France
| | - Yuxing Chen
- From the Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China and
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26
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Ryšlavá H, Kalendová A, Doubnerová V, Skočdopol P, Kumar V, Kukačka Z, Pompach P, Vaněk O, Slámová K, Bojarová P, Kulik N, Ettrich R, Křen V, Bezouška K. Enzymatic characterization and molecular modeling of an evolutionarily interesting fungal β-N-acetylhexosaminidase. FEBS J 2011; 278:2469-84. [DOI: 10.1111/j.1742-4658.2011.08173.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Vaněk O, Brynda J, Hofbauerová K, Kukačka Z, Pachl P, Bezouška K, Řezáčová P. Crystallization and diffraction analysis of β-N-acetylhexosaminidase from Aspergillus oryzae. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:498-503. [PMID: 21505251 PMCID: PMC3080160 DOI: 10.1107/s1744309111004945] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 02/09/2011] [Indexed: 11/10/2022]
Abstract
Fungal β-N-acetylhexosaminidases are enzymes that are used in the chemoenzymatic synthesis of biologically interesting oligosaccharides. The enzyme from Aspergillus oryzae was produced and purified from its natural source and crystallized using the hanging-drop vapour-diffusion method. Diffraction data from two crystal forms (primitive monoclinic and primitive tetragonal) were collected to resolutions of 3.2 and 2.4 Å, respectively. Electrophoretic and quantitative N-terminal protein-sequencing analyses confirmed that the crystals are formed by a complete biologically active enzyme consisting of a glycosylated catalytic unit and a noncovalently attached propeptide.
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Affiliation(s)
- Ondřej Vaněk
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, 14220 Prague, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University in Prague, Hlavova 8, 12840 Prague, Czech Republic
| | - Jiří Brynda
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague, Czech Republic
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 14220 Prague, Czech Republic
| | - Kateřina Hofbauerová
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, 14220 Prague, Czech Republic
| | - Zdeněk Kukačka
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, 14220 Prague, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University in Prague, Hlavova 8, 12840 Prague, Czech Republic
| | - Petr Pachl
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 14220 Prague, Czech Republic
| | - Karel Bezouška
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská 1083, 14220 Prague, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University in Prague, Hlavova 8, 12840 Prague, Czech Republic
| | - Pavlína Řezáčová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague, Czech Republic
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Vídeňská 1083, 14220 Prague, Czech Republic
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Liu T, Zhang H, Liu F, Wu Q, Shen X, Yang Q. Structural determinants of an insect beta-N-Acetyl-D-hexosaminidase specialized as a chitinolytic enzyme. J Biol Chem 2010; 286:4049-58. [PMID: 21106526 DOI: 10.1074/jbc.m110.184796] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
β-N-acetyl-D-hexosaminidase has been postulated to have a specialized function. However, the structural basis of this specialization is not yet established. OfHex1, the enzyme from the Asian corn borer Ostrinia furnacalis (one of the most destructive pests) has previously been reported to function merely in chitin degradation. Here the vital role of OfHex1 during the pupation of O. furnacalis was revealed by RNA interference, and the crystal structures of OfHex1 and OfHex1 complexed with TMG-chitotriomycin were determined at 2.1 Å. The mechanism of selective inhibition by TMG-chitotriomycin was related to the existence of the +1 subsite at the active pocket of OfHex1 and a key residue, Trp(490), at this site. Mutation of Trp(490) to Ala led to a 2,277-fold decrease in sensitivity toward TMG-chitotriomycin as well as an 18-fold decrease in binding affinity for the substrate (GlcNAc)(2). Although the overall topology of the catalytic domain of OfHex1 shows a high similarity with the human and bacterial enzymes, OfHex1 is distinguished from these enzymes by large conformational changes linked to an "open-close" mechanism at the entrance of the active site, which is characterized by the "lid" residue, Trp(448). Mutation of Trp(448) to Ala or Phe resulted in a more than 1,000-fold loss in enzyme activity, due mainly to the effect on k(cat). The current work has increased our understanding of the structure-function relationship of OfHex1, shedding light on the structural basis that accounts for the specialized function of β-N-acetyl-D-hexosaminidase as well as making the development of species-specific pesticides a likely reality.
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Affiliation(s)
- Tian Liu
- Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian 116024, China
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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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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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31
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Lunetta JM, Johnson SM, Pappagianis D. Molecular cloning, characterization and expression analysis of two β-N-acetylhexosaminidase homologs ofCoccidioides posadasii. Med Mycol 2010; 48:744-56. [DOI: 10.3109/13693780903496609] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Geisler C, Jarvis DL. Identification of genes encoding N-glycan processing beta-N-acetylglucosaminidases in Trichoplusia ni and Bombyx mori: Implications for glycoengineering of baculovirus expression systems. Biotechnol Prog 2010; 26:34-44. [PMID: 19882694 DOI: 10.1002/btpr.298] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Glycoproteins produced by non-engineered insects or insect cell lines characteristically bear truncated, paucimannose N-glycans in place of the complex N-glycans produced by mammalian cells. A key reason for this difference is the presence of a highly specific N-glycan processing beta-N-acetylglucosaminidase in insect, but not in mammalian systems. Thus, reducing or abolishing this enzyme could enhance the ability of glycoengineered insects or insect cell lines to produce complex N-glycans. Of the three insect species routinely used for recombinant glycoprotein production, the processing beta-N-acetylglucosaminidase gene has been isolated only from Spodoptera frugiperda. Thus, the purpose of this study was to isolate and characterize the genes encoding this important processing enzyme from the other two species, Bombyx mori and Trichoplusia ni. Bioinformatic analyses of putative processing beta-N-acetylglucosaminidase genes isolated from these two species indicated that each encoded a product that was, indeed, more similar to processing beta-N-acetylglucosaminidases than degradative or chitinolytic beta-N-acetylglucosaminidases. In addition, over-expression of each of these genes induced an enzyme activity with the substrate specificity characteristic of processing, but not degradative or chitinolytic enzymes. Together, these results demonstrated that the processing beta-N-acetylglucosaminidase genes had been successfully isolated from Trichoplusia ni and Bombyx mori. The identification of these genes has the potential to facilitate further glycoengineering of baculovirus-insect cell expression systems for the production of glycosylated proteins.
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Affiliation(s)
- Christoph Geisler
- Dept. of Molecular Biology, University of Wyoming, 1000 E. University Avenue, Laramie, WY 82071, USA
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Glavina Del Rio T, Abt B, Spring S, Lapidus A, Nolan M, Tice H, Copeland A, Cheng JF, Chen F, Bruce D, Goodwin L, Pitluck S, Ivanova N, Mavromatis K, Mikhailova N, Pati A, Chen A, Palaniappan K, Land M, Hauser L, Chang YJ, Jeffries CD, Chain P, Saunders E, Detter JC, Brettin T, Rohde M, Göker M, Bristow J, Eisen JA, Markowitz V, Hugenholtz P, Kyrpides NC, Klenk HP, Lucas S. Complete genome sequence of Chitinophaga pinensis type strain (UQM 2034). Stand Genomic Sci 2010; 2:87-95. [PMID: 21304681 PMCID: PMC3035255 DOI: 10.4056/sigs.661199] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chitinophaga pinensis Sangkhobol and Skerman 1981 is the type strain of the species which is the type species of the rapidly growing genus Chitinophaga in the sphingobacterial family ‘Chitinophagaceae’. Members of the genus Chitinophaga vary in shape between filaments and spherical bodies without the production of a fruiting body, produce myxospores, and are of special interest for their ability to degrade chitin. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family ‘Chitinophagaceae’, and the 9,127,347 bp long single replicon genome with its 7,397 protein-coding and 95 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.
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Xie XL, Huang QS, Wang Y, Ke CH, Chen QX. Modification and modificatory kinetics of the active center of prawn beta-N-acetyl-D-glucosaminidase. J Biomol Struct Dyn 2009; 26:781-6. [PMID: 19385706 DOI: 10.1080/07391102.2009.10507290] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Beta-N-acetyl-D-glucosaminidase (NAGase, EC3.2.1.52) plays important role in molting, digestion of chitinous foods, and defense systems against parasites in prawn (Litopenaeus vannamei). However, study on functional groups and catalytic mechanism of NAGase are yet limited. The modification of the active center of NAGase from prawn has been first studied. The results demonstrate that the disulfide bonds and the carbamidine groups of arginine residues are not essential to the enzyme's activity. The modification of indole group of tryptophan of the enzyme by N-bromosuccinimide (NBS) can lead to the complete inactivation, accompanying the absorption decreasing at 276 nm, indicating that tryptophan is essential residue to the enzyme. The modificatory kinetics of NAGase in the appropriate concentrations of NBS solution has been studied and the numbers of essential tryptophan residues have been determined using the kinetic method of the substrate reaction. The result shows that only one tryptophan residue is essential for enzyme activity. And the modifications of histidine, lysine residue, and the carboxyl groups also inactivate the enzyme completely or incompletely. The results showed that the carboxyl groups of acidic amino acid, imidazole groups of histidine residue, amino groups of lysine residue, and indole group of tryptophan were essential for the activity of enzyme.
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Affiliation(s)
- Xiao-Lan Xie
- Department of Oceanography, School of Oceanography and Environmental Sciences, Xiamen University, Xiamen 361005, China
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35
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Sumida T, Ishii R, Yanagisawa T, Yokoyama S, Ito M. Molecular cloning and crystal structural analysis of a novel beta-N-acetylhexosaminidase from Paenibacillus sp. TS12 capable of degrading glycosphingolipids. J Mol Biol 2009; 392:87-99. [PMID: 19524595 DOI: 10.1016/j.jmb.2009.06.025] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Revised: 06/04/2009] [Accepted: 06/08/2009] [Indexed: 10/20/2022]
Abstract
We report the molecular cloning and characterization of two novel beta-N-acetylhexosaminidases (beta-HEX, EC 3.2.1.52) from Paenibacillus sp. strain TS12. The two beta-HEXs (Hex1 and Hex2) were 70% identical in primary structure, and the N-terminal region of both enzymes showed significant similarity with beta-HEXs belonging to glycoside hydrolase family 20 (GH20). Interestingly, however, the C-terminal region of Hex1 and Hex2 shared no sequence similarity with the GH20 beta-HEXs or other known proteins. Both recombinant enzymes, expressed in Escherichia coli BL21(DE3), hydrolyzed the beta-N-acetylhexosamine linkage of chitooligosaccharides and glycosphingolipids such as asialo GM2 and Gb4Cer in the absence of detergent. However, the enzyme was not able to hydrolyze GM2 ganglioside in the presence or in the absence of detergent. We determined three crystal structures of Hex1; the Hex1 deletion mutant Hex1-DeltaC at a resolution of 1.8 A; Hex1-DeltaC in complex with beta-N-acetylglucosamine at 1.6 A; and Hex1-DeltaC in complex with beta-N-acetylgalactosamine at 1.9 A. We made a docking model of Hex1-DeltaC with GM2 oligosaccharide, revealing that the sialic acid residue of GM2 could hinder access of the substrate to the active site cavity. This is the first report describing the molecular cloning, characterization and X-ray structure of a procaryotic beta-HEX capable of hydrolyzing glycosphingolipids.
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Affiliation(s)
- Tomomi Sumida
- Department of Bioscience and Biotechnology, Kyushu University, Hakozaki, Higashi-ku, Fukuoka, Japan
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36
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Loss of a biofilm-inhibiting glycosyl hydrolase during the emergence of Yersinia pestis. J Bacteriol 2008; 190:8163-70. [PMID: 18931111 DOI: 10.1128/jb.01181-08] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Yersinia pestis, the bacterial agent of plague, forms a biofilm in the foregut of its flea vector to produce a transmissible infection. The closely related Yersinia pseudotuberculosis, from which Y. pestis recently evolved, can colonize the flea midgut but does not form a biofilm in the foregut. Y. pestis biofilm in the flea and in vitro is dependent on an extracellular matrix synthesized by products of the hms genes; identical genes are present in Y. pseudotuberculosis. The Yersinia Hms proteins contain functional domains present in Escherichia coli and Staphylococcus proteins known to synthesize a poly-beta-1,6-N-acetyl-D-glucosamine biofilm matrix. In this study, we show that the extracellular matrices (ECM) of Y. pestis and staphylococcal biofilms are antigenically related, indicating a similar biochemical structure. We also characterized a glycosyl hydrolase (NghA) of Y. pseudotuberculosis that cleaved beta-linked N-acetylglucosamine residues and reduced biofilm formation by staphylococci and Y. pestis in vitro. The Y. pestis nghA ortholog is a pseudogene, and overexpression of functional nghA reduced ECM surface accumulation and inhibited the ability of Y. pestis to produce biofilm in the flea foregut. Mutational loss of this glycosidase activity in Y. pestis may have contributed to the recent evolution of flea-borne transmission.
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Jin ZX, Zhang JP, Yan YW, Wang Q. Studies on the chemical modification of the essential groups of N-Acetyl-beta-D-glucosaminidase from viscera of green crab (Scylla Serrata). Appl Biochem Biotechnol 2008; 149:119-27. [PMID: 18401742 DOI: 10.1007/s12010-007-8109-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Accepted: 11/21/2007] [Indexed: 11/25/2022]
Abstract
The chemical modification of N-acetyl-beta-D: -glucosaminidase (EC3.2.1.30) from viscera of green crab (Scylla serrata) has been first studied. The modification of indole groups of tryptophan of the enzyme by N-bromosuccinimide can lead to complete inactivation, accompanying the absorption decreasing at 275 nm and the fluorescence intensity quenching at 338 nm, indicating that tryptophan is essential residue to the enzyme. The modification of histidine residue, the carboxyl groups, and lysine residue inactivates the enzyme completely or incompletely. The results show that imidazole groups of histidine residue or sulfhydryl residues, the carboxyl groups of acidic amino acid, amino groups of lysine residue, and indole groups of tryptophan were essential for the catalytic activity of enzyme, while the results demonstrate that the disulfide bonds and the carbamidine groups of arginine residues are not essential to the enzyme's function.
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Affiliation(s)
- Zhu-Xing Jin
- Key Laboratory of Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Science, Xiamen University, Xiamen 361005, People's Republic of China
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Family 18 chitolectins: comparison of MGP40 and HUMGP39. Biochem Biophys Res Commun 2007; 359:221-6. [PMID: 17543889 DOI: 10.1016/j.bbrc.2007.05.074] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Accepted: 05/08/2007] [Indexed: 11/21/2022]
Abstract
Glycosidase and lectins both bind sugars, but only the glycosidases have catalytic activity. The glycosidases occur among over 100 evolved protein families and Family 18 is one of the two chitinases (EC 3, 2.1.14) families. Interestingly, lectins are also in this evolutionary group of Family 18 glycosidase proteins. The proteins belonging to the enzymatically inactive class are referred to as chitolectins and have a binding site that is highly similar to the catalytic Family 18 enzymes. We present a comparison of the recently obtained structures of two Family 18 chitolectins, MGP40 [A.K. Mohanty, G. Singh, M. Paramasivam, K. Saravanan, T. Jabeen, S. Sharma, S. Yadav, P. Kaur, P. Kumar, A. Srinivasan, T.P. Singh, Crystal structure of a novel regulatory 40kDa mammary gland protein (MGP-40) secreted during involution, J. Biol. Chem. 278 (2003) 14451-14460.] and HumGP39 [F. Fusetti, T. Pijning, K.H. Kalk, E. Bos, B.W. Dijkstra, Crystal structure and carbohydrate-binding properties of the human cartilage glycoprotein-39, J. Biol. Chem. 278 (2003) 37753-37760; D.R. Houston, D.R. Anneliese, C.K. Joanne, D.M.V. Aalten, Structure and ligand-induced conformational change of the 39kDa glycoprotein from human articular chondrocytes, J. Biol. Chem. 278 (2003) 30206-30212.] with a focus on the glycosidase active site. We compare the sequence and the structure of these two Family 18 protein classes. The difference between the active and inactive protein is a glutamic acid which acts as the essential acid/base residue for chitin cleavage and is replaced with leucine or glutamine in the chitolectins. Furthermore, a mechanism for the interaction between the chitolectin and oligosaccharides was proposed.
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Ettrich R, Kopecký V, Hofbauerová K, Baumruk V, Novák P, Pompach P, Man P, Plíhal O, Kutý M, Kulik N, Sklenář J, Ryšlavá H, Křen V, Bezouška K. Structure of the dimeric N-glycosylated form of fungal beta-N-acetylhexosaminidase revealed by computer modeling, vibrational spectroscopy, and biochemical studies. BMC STRUCTURAL BIOLOGY 2007; 7:32. [PMID: 17509134 PMCID: PMC1885261 DOI: 10.1186/1472-6807-7-32] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Accepted: 05/17/2007] [Indexed: 11/29/2022]
Abstract
Background Fungal β-N-acetylhexosaminidases catalyze the hydrolysis of chitobiose into its constituent monosaccharides. These enzymes are physiologically important during the life cycle of the fungus for the formation of septa, germ tubes and fruit-bodies. Crystal structures are known for two monomeric bacterial enzymes and the dimeric human lysosomal β-N-acetylhexosaminidase. The fungal β-N-acetylhexosaminidases are robust enzymes commonly used in chemoenzymatic syntheses of oligosaccharides. The enzyme from Aspergillus oryzae was purified and its sequence was determined. Results The complete primary structure of the fungal β-N-acetylhexosaminidase from Aspergillus oryzae CCF1066 was used to construct molecular models of the catalytic subunit of the enzyme, the enzyme dimer, and the N-glycosylated dimer. Experimental data were obtained from infrared and Raman spectroscopy, and biochemical studies of the native and deglycosylated enzyme, and are in good agreement with the models. Enzyme deglycosylated under native conditions displays identical kinetic parameters but is significantly less stable in acidic conditions, consistent with model predictions. The molecular model of the deglycosylated enzyme was solvated and a molecular dynamics simulation was run over 20 ns. The molecular model is able to bind the natural substrate – chitobiose with a stable value of binding energy during the molecular dynamics simulation. Conclusion Whereas the intracellular bacterial β-N-acetylhexosaminidases are monomeric, the extracellular secreted enzymes of fungi and humans occur as dimers. Dimerization of the fungal β-N-acetylhexosaminidase appears to be a reversible process that is strictly pH dependent. Oligosaccharide moieties may also participate in the dimerization process that might represent a unique feature of the exclusively extracellular enzymes. Deglycosylation had only limited effect on enzyme activity, but it significantly affected enzyme stability in acidic conditions. Dimerization and N-glycosylation are the enzyme's strategy for catalytic subunit stabilization. The disulfide bridge that connects Cys448 with Cys483 stabilizes a hinge region in a flexible loop close to the active site, which is an exclusive feature of the fungal enzymes, neither present in bacterial nor mammalian structures. This loop may play the role of a substrate binding site lid, anchored by a disulphide bridge that prevents the substrate binding site from being influenced by the flexible motion of the loop.
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Affiliation(s)
- Rüdiger Ettrich
- Laboratory of High Performance Computing, Institute of Systems Biology and Ecology of the Academy of Sciences of the Czech Republic and Institute of Physical Biology of USB, Zámek136, CZ-37333 Nové Hrady, Czech Republic
| | - Vladimír Kopecký
- Institute of Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu5, CZ-12116 Prague2, Czech Republic
| | - Kateřina Hofbauerová
- Institute of Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu5, CZ-12116 Prague2, Czech Republic
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
| | - Vladimír Baumruk
- Institute of Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu5, CZ-12116 Prague2, Czech Republic
| | - Petr Novák
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
| | - Petr Pompach
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University, Albertov2030, CZ-12840 Prague2, Czech Republic
| | - Petr Man
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
| | - Ondřej Plíhal
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
| | - Michal Kutý
- Laboratory of High Performance Computing, Institute of Systems Biology and Ecology of the Academy of Sciences of the Czech Republic and Institute of Physical Biology of USB, Zámek136, CZ-37333 Nové Hrady, Czech Republic
| | - Natallia Kulik
- Laboratory of High Performance Computing, Institute of Systems Biology and Ecology of the Academy of Sciences of the Czech Republic and Institute of Physical Biology of USB, Zámek136, CZ-37333 Nové Hrady, Czech Republic
| | - Jan Sklenář
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University, Albertov2030, CZ-12840 Prague2, Czech Republic
| | - Helena Ryšlavá
- Department of Biochemistry, Faculty of Science, Charles University, Albertov2030, CZ-12840 Prague2, Czech Republic
| | - Vladimír Křen
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
| | - Karel Bezouška
- Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídeňská1083, CZ-14220 Prague4, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University, Albertov2030, CZ-12840 Prague2, Czech Republic
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Cattaneo F, Pasini ME, Intra J, Matsumoto M, Briani F, Hoshi M, Perotti ME. Identification and expression analysis of Drosophila melanogaster genes encoding beta-hexosaminidases of the sperm plasma membrane. Glycobiology 2006; 16:786-800. [PMID: 16733265 DOI: 10.1093/glycob/cwl007] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sperm surface beta-N-acetylhexosaminidases are among the molecules mediating early gamete interactions in invertebrates and vertebrates, including man. The plasma membrane of Drosophila spermatozoa contains two beta-N-acetylhexosaminidases, DmHEXA and DmHEXB, which are required for egg fertilization. Here, we demonstrate that three putative Drosophila melanogaster genes predicted to code for beta-N-acetylhexosaminidases, Hexo1, Hexo2, and fdl, are all expressed in the male germ line. fdl codes for a homolog of the alpha-subunit of the mammalian lysosomal beta-N-acetylhexosaminidase Hex A. Hexo1 and Hexo2 encode two homologs of the beta-subunit of all known beta-N-acetylhexosaminidases, which we have named beta(1) and beta(2), respectively. Immunoblot analysis of sperm proteins indicated that the gene products associate in different heterodimeric combinations forming DmHEXA, with an alphabeta(2) structure, and DmHEXB, with a beta(1)beta(2) structure. Immunofluorescence demonstrated that all the gene products localized to the sperm plasma membrane. Although none of the genes was testis-specific, fdl was highly and preferentially expressed in the testis, whereas Hexo1 and Hexo2 showed broader tissue expression. Enzyme assays carried out on testis and on a variety of somatic tissues corroborated the results of gene expression analysis. These findings for the first time show the in vivo expression in insects of genes encoding beta-N-acetylhexosaminidases, the only molecules so far identified as involved in sperm/egg recognition in this class, whereas in mammals, the organisms where these enzymes have been best studied, only two types of polypeptide chains forming dimeric functional beta-N-acetylhexosaminidases are present in Drosophila three different gene products are available that might generate numerous dimeric isoforms.
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Affiliation(s)
- F Cattaneo
- Department of Biosciences and Informatics, Keio University, Kohoku Ku, Yokohama, Kanagawa 2238522, Japan
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41
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Cetinbaş N, Macauley MS, Stubbs KA, Drapala R, Vocadlo DJ. Identification of Asp174 and Asp175 as the key catalytic residues of human O-GlcNAcase by functional analysis of site-directed mutants. Biochemistry 2006; 45:3835-44. [PMID: 16533067 DOI: 10.1021/bi052370b] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
O-GlcNAcase is a family 84 beta-N-acetylglucosaminidase catalyzing the hydrolytic cleavage of beta-O-linked 2-acetamido-2-deoxy-d-glycopyranose (O-GlcNAc) from serine and threonine residues of posttranslationally modified proteins. O-GlcNAcases use a double-displacement mechanism involving formation and breakdown of a transient bicyclic oxazoline intermediate. The key catalytic residues of any family 84 enzyme facilitating this reaction, however, are unknown. Two mutants of human O-GlcNAcase, D174A and D175A, were generated since these residues are highly conserved among family 84 glycoside hydrolases. Structure-reactivity studies of the D174A mutant enzyme reveals severely impaired catalytic activity across a broad range of substrates alongside a pH-activity profile consistent with deletion of a key catalytic residue. The D175A mutant enzyme shows a significant decrease in catalytic efficiency with substrates bearing poor leaving groups (up to 3000-fold), while for substates bearing good leading groups the difference is much smaller (7-fold). This mutant enzyme also cleaves thioglycosides with essentially the same catalytic efficiency as the wild-type enzyme. As well, addition of azide as an exogenous nucleophile increases the activity of this enzyme toward a substrate bearing an excellent leaving group. Together, these results allow unambiguous assignment of Asp(174) as the residue that polarizes the 2-acetamido group for attack on the anomeric center and Asp(175) as the residue that functions as the general acid/base catalyst. Therefore, the family 84 glycoside hydrolases use a DD catalytic pair to effect catalysis.
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Affiliation(s)
- Naniye Cetinbaş
- Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada, V5A 1S6
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42
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Pyrpassopoulos S, Vlassi M, Tsortos A, Papanikolau Y, Petratos K, Vorgias CE, Nounesis G. Equilibrium heat-induced denaturation of chitinase 40 from Streptomyces thermoviolaceus. Proteins 2006; 64:513-23. [PMID: 16685709 DOI: 10.1002/prot.21003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
High-precision differential scanning calorimetry (DSC) and circular dichroism (CD) have been employed to study the thermal unfolding of chitinase 40 (Chi40) from Streptomyces thermoviolaceus. Chi40 belongs to family 18 of glycosyl hydrolase superfamily bearing a catalytic domain with a "TIM barrel"-like fold, which exhibits deviations from the (beta/alpha)8 fold. The thermal unfolding is reversible at pH = 8.0 and 9.0. The denatured state is characterized by extensive structural changes with respect to the native. The process is characterized by slow relaxation kinetics. Even slower refolding rates are recorded upon cooling. It is shown that the denaturation calorimetric data obtained at slow heating rate (0.17 K/min) are in excellent agreement with equilibrium data obtained by extrapolation of the experimental results to zero scanning rate. Analysis of the DSC results reveals that the experimental data can be successfully fitted using either a non-two-state sequential model involving one equilibrium intermediate, or an independent transitions model involving the unfolding of two Chi40 energetic domains to intermediate states. The stability of the native state with respect to the final denatured state is estimated, deltaG = 24.0 kcal/mol at 25 degrees C. The thermal results are in agreement with previous findings from chemical denaturation studies of a wide variety of (beta/alpha)8 barrel proteins, that their unfolding is a non-two-state process, always involving at least one unfolding intermediate.
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43
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Aronson NN, Halloran BA, Alexeyev MF, Zhou XE, Wang Y, Meehan EJ, Chen L. Mutation of a conserved tryptophan in the chitin-binding cleft of Serratia marcescens chitinase A enhances transglycosylation. Biosci Biotechnol Biochem 2006; 70:243-51. [PMID: 16428843 DOI: 10.1271/bbb.70.243] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Family 18 chitinases have the signature peptide DGXDXDXE forming the fourth beta-strand in the (beta/alpha)8-barrel of their catalytic domain. The carboxyl-end glutamic acid, E315 in Serratia marcescens chitinase A, serves as the acid/base during chitin hydrolysis, and the side-chain of the preceding aspartic acid, D313, helps to position correctly the N-acetyl moiety of the glycosyl sugar undergoing hydrolysis. Chitin substrates are bound within a long cleft across the top of the barrel, whose floor consists of aromatic residues that hydrophobically stack with every other GlcNAc. Alanine substitution of the conserved Trp167 at the -3 subsite in Serratia marcescens chitinase A enhanced transglycosylation. Higher oligosaccharides were formed from both chitin tetra- and pentasaccharide, and the only hydrolytic product from chitin trisaccharide was the disaccharide. Greater retention of the glycosyl fragment at the active site of the -3 mutant of Serratia marcescens chitinase A might favor transglycosylation due to a stabilized conformation of its D313.
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Affiliation(s)
- Nathan N Aronson
- Department of Biochemistry and Molecular Biology, University of South Alabama, AL 36688, USA.
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44
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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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45
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Buser S, Vasella A. 7-Oxanorbornane and Norbornane Mimics of a Distortedβ-D-Mannopyranoside: Synthesis and Evaluation asβ-Mannosidase Inhibitors. Helv Chim Acta 2005. [DOI: 10.1002/hlca.200590255] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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46
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Vocadlo DJ, Withers SG. Detailed Comparative Analysis of the Catalytic Mechanisms of β-N-Acetylglucosaminidases from Families 3 and 20 of Glycoside Hydrolases. Biochemistry 2005; 44:12809-18. [PMID: 16171396 DOI: 10.1021/bi051121k] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Beta-N-acetylglucosaminidases are commonly occurring enzymes involved in the degradation of polysaccharides and glycoconjugates containing N-acetylglucosamine residues. Such enzymes have been classified into glycoside hydrolase families 3 and 20 and are believed to follow distinct chemical mechanisms. Family 3 enzymes are thought to follow a standard retaining mechanism involving a covalent glycosyl enzyme intermediate while family 20 enzymes carry out a substrate-assisted mechanism involving the transient formation of an enzyme-sequestered oxazoline or oxazolinium ion intermediate. Detailed mechanistic analysis of representatives of these two families provides support for these mechanisms as well as detailed insights into transition state structure. Alpha-secondary deuterium kinetic isotope effects of kH/kD = 1.07 and 1.10 for Streptomyces plicatus beta-hexosaminidase (SpHex) and Vibrio furnisii beta-N-acetylglucosaminidase (ExoII) respectively indicate transition states with oxocarbenium ion character in each case. Brønsted plots for hydrolysis of a series of aryl hexosaminides are quite different in the two cases. For SpHex a large degree of proton donation is suggested by the relatively low value of beta(lg) (-0.29) on kcat/Km, compared with a beta(lg) of -0.79 for ExoII. Most significantly the Taft plots derived from kinetic parameters for a series of p-nitrophenyl N-acyl glucosaminides bearing differing levels of fluorine substitution in the N-acyl group are completely different. A very strong dependence (slope = -1.29) is seen for SpHex, indicating direct nucleophilic participation by the acetamide, while essentially no dependence (0.07) is seen for ExoII, suggesting that the acetamide plays purely a binding role. Taken together these data provide unprecedented insight into enzymatic glycosyl transfer mechanisms wherein the structures of both the nucleophile and the leaving group are systematically varied.
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Affiliation(s)
- David J Vocadlo
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
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47
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Rao FV, Houston DR, Boot RG, Aerts JMFG, Hodkinson M, Adams DJ, Shiomi K, Omura S, van Aalten DMF. Specificity and affinity of natural product cyclopentapeptide inhibitors against A. fumigatus, human, and bacterial chitinases. ACTA ACUST UNITED AC 2005; 12:65-76. [PMID: 15664516 DOI: 10.1016/j.chembiol.2004.10.013] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2004] [Revised: 10/07/2004] [Accepted: 10/14/2004] [Indexed: 11/30/2022]
Abstract
Family 18 chitinases play key roles in organisms ranging from bacteria to man. There is a need for specific, potent inhibitors to probe the function of these chitinases in different organisms. Such molecules could also provide leads for the development of chemotherapeuticals with fungicidal, insecticidal, or anti-inflammatory potential. Recently, two natural product peptides, argifin and argadin, have been characterized, which structurally mimic chitinase-chitooligosaccharide interactions and inhibit a bacterial chitinase in the nM-mM range. Here, we show that these inhibitors also act on human and Aspergillus fumigatus chitinases. The structures of these enzymes in complex with argifin and argadin, together with mutagenesis, fluorescence, and enzymology, reveal that subtle changes in the binding site dramatically affect affinity and selectivity. The data show that it may be possible to develop specific chitinase inhibitors based on the argifin/argadin scaffolds.
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Affiliation(s)
- Francesco V Rao
- Division of Biological Chemistry & Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland
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48
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Böhm M, Vasella A. Probing the Conformational Changes in the Enzymatic Hydrolysis of 2-Acetamido-2-deoxy-β-D-glucopyranosides. Helv Chim Acta 2004. [DOI: 10.1002/hlca.200490229] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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49
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Harty DWS, Chen Y, Simpson CL, Berg T, Cook SL, Mayo JA, Hunter N, Jacques NA. Characterisation of a novel homodimeric N-acetyl-beta-D-glucosaminidase from Streptococcus gordonii. Biochem Biophys Res Commun 2004; 319:439-47. [PMID: 15178426 DOI: 10.1016/j.bbrc.2004.05.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2004] [Indexed: 11/28/2022]
Abstract
An N-acetyl-beta-D-glucosaminidase (GcnA) from Streptococcus gordonii FSS2 was cloned and sequenced. GcnA had a deduced molecular mass of 72,120 Da. The molecular weight after gel-filtration chromatography was 140,000 Da and by SDS-PAGE was 70,000 Da, indicating that the native protein was a homodimer. The deduced amino acid sequence had significant homology to a glycosyl hydrolase from Streptococcus pneumoniae and the conserved catalytic domain of the Family 20 glycosyl hydrolases. GcnA catalysed the hydrolysis of the synthetic substrates, 4-methylumbelliferyl (4MU)-N-acetyl-beta-D-glucosaminide, 4MU-N-acetyl-beta-D-galactosaminide, 4-MU-beta-D-N,N'-diacetylchitobioside, and 4-MU-beta-D-N,N',N''-chitotrioside as well as the respective chito-oligosaccharides. GcnA was optimally active at pH 6.6 and 42 degrees C. The Km for 4-MU-beta-D-N,N',N''-chitotrioside, 45 microM, was the lowest for all the substrates tested. Hg2+, Cu2+, Fe2+, and Zn2+ completely inhibited while Co2+, Mn2+, and Ni2+ partially inhibited activity. S. gordonii FSS2 and a GcnA negative mutant grew equally well on chito-oligosaccharides as substrates. The S. gordonii sequencing projects indicate two further N-acetyl-beta-D-glucosaminidase activities.
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Affiliation(s)
- Derek W S Harty
- Institute of Dental Research, Millennium Institute, Westmead Centre for Oral Health, Westmead, Australia.
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50
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Santos MO, Pereira M, Felipe MSS, Jesuino RSA, Ulhoa CJ, Soares RDBA, Soares CMDA. Molecular cloning and characterization of a cDNA encoding the N-acetyl-β-D-glucosaminidase homologue ofParacoccidioidesbrasiliensis. Med Mycol 2004; 42:247-53. [PMID: 15283239 DOI: 10.1080/13693780310001644671] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
A cDNA encoding the N-acetyl-beta-D-glucosaminidase (NAG) protein of Paracoccidioides brasiliensis, Pb NAG1, was cloned and characterized. The 2663-nucleotide sequence of the cDNA consisted of a single open reading frame encoding a protein with a predicted molecular mass of 64.73 kDa and an isoeletric point of 6.35. The predicted protein includes a putative 30-amino-acid signal peptide. The protein as a whole shares considerable sequence similarity with 'classic' NAG. The primary sequence of Pb NAG1 was used to infer phylogenetic relationships. The amino acid sequence of Pb NAG1 has 45, 31 and 30% identity, respectively, with homologous sequences from Trichoderma harzianum, Aspergillus nidulans and Candida albicans. In particular, striking homology was observed with the active site regions of the glycosyl hydrolase group of proteins (family 20). The expected active site consensus motif G X D E and catalytic Asp and Glu residues at positions 373 and 374 were found, reinforcing that Pb NAG1 belongs to glycosyl hydrolase family 20. The nucleotide sequence of Pb nag1 and its flanking regions have been deposited, along with the amino acid sequence of the deduced protein, in GenBank under accession number AF419158.
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MESH Headings
- 5' Untranslated Regions/genetics
- Acetylglucosaminidase/genetics
- Acetylglucosaminidase/isolation & purification
- Amino Acid Sequence
- Aspergillus nidulans/genetics
- Base Sequence
- Binding Sites/genetics
- Candida albicans/genetics
- Catalytic Domain/genetics
- Cloning, Molecular
- Codon, Initiator/genetics
- Codon, Terminator/genetics
- Conserved Sequence/genetics
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA, Fungal/chemistry
- DNA, Fungal/genetics
- DNA, Fungal/isolation & purification
- Fungal Proteins/genetics
- Fungal Proteins/physiology
- Genes, Fungal/genetics
- Genes, Fungal/physiology
- Molecular Sequence Data
- Molecular Weight
- Open Reading Frames/genetics
- Paracoccidioides/enzymology
- Paracoccidioides/genetics
- Phylogeny
- Protein Sorting Signals/genetics
- RNA 3' Polyadenylation Signals/genetics
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Trichoderma/genetics
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Affiliation(s)
- Mônica O Santos
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
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