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Zhang YS, Gong JS, Yao ZY, Jiang JY, Su C, Li H, Kang CL, Liu L, Xu ZH, Shi JS. Insights into the source, mechanism and biotechnological applications of hyaluronidases. Biotechnol Adv 2022; 60:108018. [PMID: 35853550 DOI: 10.1016/j.biotechadv.2022.108018] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 07/11/2022] [Accepted: 07/13/2022] [Indexed: 01/10/2023]
Abstract
It has long been found that hyaluronidases exist in a variety of organisms, playing their roles in various biological processes including infection, envenomation and metabolic regulation through degrading hyaluronan. However, exploiting them as a bioresource for specific applications had not been extensively studied until the latest decades. In recent years, new application scenarios have been developed, which extended the field of application, and emphasized the research value of hyaluronidase. This critical review comprehensively summarizes existing studies on hyaluronidase from different source, particularly in their structures, action patterns, and biological functions in human and mammals. Furthermore, we give in-depth insight into the resource mining and protein engineering process of hyaluronidase, as well as strategies for their high-level production, indicating that mixed strategies should be adopted to obtain well-performing hyaluronidase with efficiency. In addition, advances in application of hyaluronidase were summarized and discussed. Finally, prospects for future researches are proposed, highlighting the importance of further investigation into the characteristics of hyaluronidases, and the necessity of investigating their products for the development of their application value.
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Affiliation(s)
- Yue-Sheng Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi 214122, PR China; National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi 214122, PR China.
| | - Zhi-Yuan Yao
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China; Jiangsu Provincial Engineering Research Center for Bioactive Product Processing, Jiangnan University, Wuxi 214122, PR China
| | - Jia-Yu Jiang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi 214122, PR China
| | - Chang Su
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi 214122, PR China
| | - Heng Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi 214122, PR China
| | - Chuan-Li Kang
- Shandong Engineering Laboratory of Sodium Hyaluronate and its Derivatives, Shandong Focusfreda Biotech Co., Ltd, Qufu 273165, PR China
| | - Lei Liu
- Shandong Engineering Laboratory of Sodium Hyaluronate and its Derivatives, Shandong Focusfreda Biotech Co., Ltd, Qufu 273165, PR China
| | - Zheng-Hong Xu
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China; Jiangsu Provincial Engineering Research Center for Bioactive Product Processing, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi 214122, PR China
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2
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Suits MDL, Pluvinage B, Law A, Liu Y, Palma AS, Chai W, Feizi T, Boraston AB. Conformational analysis of the Streptococcus pneumoniae hyaluronate lyase and characterization of its hyaluronan-specific carbohydrate-binding module. J Biol Chem 2014; 289:27264-27277. [PMID: 25100731 PMCID: PMC4175358 DOI: 10.1074/jbc.m114.578435] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
For a subset of pathogenic microorganisms, including Streptococcus pneumoniae, the recognition and degradation of host hyaluronan contributes to bacterial spreading through the extracellular matrix and enhancing access to host cell surfaces. The hyaluronate lyase (Hyl) presented on the surface of S. pneumoniae performs this role. Using glycan microarray screening, affinity electrophoresis, and isothermal titration calorimetry we show that the N-terminal module of Hyl is a hyaluronan-specific carbohydrate-binding module (CBM) and the founding member of CBM family 70. The 1.2 Å resolution x-ray crystal structure of CBM70 revealed it to have a β-sandwich fold, similar to other CBMs. The electrostatic properties of the binding site, which was identified by site-directed mutagenesis, are distinct from other CBMs and complementary to its acidic ligand, hyaluronan. Dynamic light scattering and solution small angle x-ray scattering revealed the full-length Hyl protein to exist as a monomer/dimer mixture in solution. Through a detailed analysis of the small angle x-ray scattering data, we report the pseudoatomic solution structures of the monomer and dimer forms of the full-length multimodular Hyl.
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Affiliation(s)
- Michael D L Suits
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada
| | - Benjamin Pluvinage
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada
| | - Adrienne Law
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada
| | - Yan Liu
- Glycosciences Laboratory, Imperial College London, Burlington Danes Building, Du Cane Road, London W12 0NN, United Kingdom, and
| | - Angelina S Palma
- Glycosciences Laboratory, Imperial College London, Burlington Danes Building, Du Cane Road, London W12 0NN, United Kingdom, and; REQUIMTE, Department of Chemistry, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Wengang Chai
- Glycosciences Laboratory, Imperial College London, Burlington Danes Building, Du Cane Road, London W12 0NN, United Kingdom, and
| | - Ten Feizi
- Glycosciences Laboratory, Imperial College London, Burlington Danes Building, Du Cane Road, London W12 0NN, United Kingdom, and
| | - Alisdair B Boraston
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada,.
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3
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Khan AH, Mohamed Omar YM, Kakar MA, Bangulzai N. Crystallization and preliminary crystallographic analysis of recombinant hyaluronate lyase from Streptococcus suis. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:673-5. [PMID: 23722851 PMCID: PMC3668592 DOI: 10.1107/s1744309113012554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 05/07/2013] [Indexed: 11/10/2022]
Abstract
Hyaluronate lyase is an important surface enzyme of many streptococcal species. The enzyme degrades several biologically important connective tissue components, which facilitates the spreading of the bacteria throughout the host tissues and presumably provides energy and a carbon source for bacterial cells. Recombinant hyaluronate lyase was expressed in Escherichia coli and was crystallized using the hanging-drop vapour-diffusion method. The crystals belonged to space group P222(1), with unit-cell parameters a = 58.08, b = 101.32, c = 103.47 Å and one molecule in the asymmetric unit. Diffraction data were collected to 2.50 Å resolution.
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Affiliation(s)
- Abdul Hamid Khan
- Department of Microbiology, Lasbela University of Agriculture, Water and Marine Sciences, Uthal, Pakistan.
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4
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Joshi HV, Jedrzejas MJ, de Groot BL. Domain motions of hyaluronan lyase underlying processive hyaluronan translocation. Proteins 2009; 76:30-46. [PMID: 19089975 DOI: 10.1002/prot.22316] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Hyaluronan lyase (Hyal) is a surface enzyme occurring in many bacterial organisms including members of Streptococcus species. Streptococcal Hyal primarily degrades hyaluronan-substrate (HA) of the extracellular matrix. This degradation appears to facilitate the spread of this bacterium throughout host tissues. Unlike purely endolytic degradation of its other substrates, unsulfated chondroitin or some chondroitin sulfates, the degradation of HA by Hyal proceeds by processive exolytic cleavage of one disaccharide at a time following an initial endolytic cut. Molecular dynamics (MD) studies of Hyal from Streptococcus pneumoniae are presented that address the enzyme's molecular mechanism of action and the role of domain motions for processive functionality. The analysis of extensive sub-microsecond MD simulations of this enzyme action on HA-substrates of different lengths and the connection between the domain dynamics of Hyal and the translocation of the HA-substrate reveals that opening/closing and twisting domain motions of the Hyal are intimately linked to processive HA degradation. Enforced simulations confirmed this finding as the domain motions in SpnHyal were found to be induced by enforced substrate translocation. These results establish the dynamic interplay between Hyal flexibility and substrate translocation and provide insight into the processive mechanism of Hyal.
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Affiliation(s)
- Harshad V Joshi
- Computational Biomolecular Dynamics Group, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
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Stern R, Jedrzejas MJ. Carbohydrate Polymers at the Center of Life’s Origins: The Importance of Molecular Processivity. Chem Rev 2008; 108:5061-85. [DOI: 10.1021/cr078240l] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Robert Stern
- Department of Pathology and Comprehensive Cancer Center, School of Medicine, University of California, San Francisco, California 94143, Microdesign Institute, 29 Kingwood Rd., Oakland, California 94619, and Center for Immunobiology and Vaccine Development, Children’s Hospital Oakland Research Institute, 5700 Martin Luther King, Jr. Way, Oakland, California 94609
| | - Mark J. Jedrzejas
- Department of Pathology and Comprehensive Cancer Center, School of Medicine, University of California, San Francisco, California 94143, Microdesign Institute, 29 Kingwood Rd., Oakland, California 94619, and Center for Immunobiology and Vaccine Development, Children’s Hospital Oakland Research Institute, 5700 Martin Luther King, Jr. Way, Oakland, California 94609
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6
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Akhtar MS, Bhakuni V. Role of ionic interactions and linker in the domain interaction and modulation of functional activity of hyaluronate lyases. Biochem Biophys Res Commun 2007; 353:286-92. [PMID: 17188648 DOI: 10.1016/j.bbrc.2006.12.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Accepted: 12/02/2006] [Indexed: 11/26/2022]
Abstract
Hyaluronate lyases from Streptococcus pneumoniae (SpnHL) and Streptococcus agalactiae (SagHL) are composed of four domains; N-terminal domain, spacer domain, alpha-domain and C-terminal domain, which are connected through peptide linkers. We have earlier shown that the recombinant alpha- and C-terminal domains of SpnHL/SagHL interact with each other even in absence of the linker and form a functional complex with enhanced enzymatic activity. Here, we looked into the role of ionic interactions in the enzyme stability and also the role of C-terminal domain and linker in the functional regulation. Domain swapping studies showed that the C-terminal domain does not bind directly to the substrate; instead the domain contributes to the interaction with the polymeric hyaluronan for catalysis. Furthermore, the substrate specificity exchanges with the size of catalytic cleft. The role of linker connecting alpha-domain to C-terminal domain was found to hold the C-terminal domain in a conformation suitable for achieving maximum activity.
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Affiliation(s)
- Md Sohail Akhtar
- Molecular and Structural Biology Division, Central Drug Research Institute, Lucknow 226 001, India
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7
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Matalon R, Surendran S, Campbell GA, Michals-Matalon K, Tyring SK, Grady J, Cheng S, Kaye E. Hyaluronidase increases the biodistribution of acid alpha-1,4 glucosidase in the muscle of Pompe disease mice: an approach to enhance the efficacy of enzyme replacement therapy. Biochem Biophys Res Commun 2006; 350:783-7. [PMID: 17027913 DOI: 10.1016/j.bbrc.2006.09.133] [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] [Received: 09/20/2006] [Accepted: 09/22/2006] [Indexed: 11/18/2022]
Abstract
Pompe disease (glycogen storage disease type II) is a glycogen storage disease caused by a deficiency of the lysosomal enzyme, acid maltase/acid alpha-1,4 glucosidase (GAA). Deficiency of the enzyme leads primarily to intra-lysosomal glycogen accumulation, primarily in cardiac and skeletal muscles, due to the inability of converting glycogen into glucose. Enzyme replacement therapy (ERT) has been applied to replace the deficient enzyme and to restore the lost function. However, enhancing the enzyme activity to the muscle following ERT is relatively insufficient. In order to enhance GAA activity into the muscle in Pompe disease, efficacy of hyaluronidase (hyase) was examined in the heart, quadriceps, diaphragm, kidney, and brain of mouse model of Pompe disease. Administration of hyase 3000 U/mouse (intravenous) i.v. or i.p. (intraperitoneal) and 10 min later recombinant human GAA (rhGAA) 20 mg/kg i.v. showed more GAA activity in hyase i.p. injected mice compared to those mice injected with hyase via i.v. Injection of low dose of hyase (3000 U/mouse) or high dose of hyase (10,000 U/mouse) i.p. and 20 min or 60 min later 20 mg/kg rhGAA i.v. increased GAA activity into the heart, diaphragm, kidney, and quadriceps compared to hyase untreated mice. These studies suggest that hyase enhances penetration of enzyme into the tissues including muscle during ERT and therefore hyase pretreatment may be important in treating Pompe disease.
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Affiliation(s)
- Reuben Matalon
- Department of Pediatrics, The University of Texas Medical Branch, Galveston, TX 77555-0359, USA.
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Akhtar MS, Krishnan MY, Bhakuni V. Insights into the Mechanism of Action of Hyaluronate Lyase. J Biol Chem 2006; 281:28336-44. [PMID: 16854993 DOI: 10.1074/jbc.m601165200] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Hyaluronate lyases (HLs) cleave hyaluronan and certain other chondroitin/chondroitin sulfates. Although native HL from Streptococcus agalactiae is composed of four domains, it finally stabilizes after autocatalytic conversion as a 92-kDa enzyme composed of the N-terminal spacer, middle alpha-, and C-terminal domains. These three domains are independent folding/unfolding units of the enzyme. Comparative structural and functional studies using the enzyme and its various fragments/domains suggest a relatively insignificant role of the N-terminal spacer domain in the 92-kDa enzyme. Functional studies demonstrate that the alpha-domain is the catalytic domain. However, independently it has a maximum of only about 10% of the activity of the 92-kDa enzyme, whereas its complex with the C-terminal domain in vitro shows a significant enhancement (about 6-fold) in the activity. It has been previously proposed that the C-terminal domain modulates the enzymatic activity of HLs. In addition, one of the possible roles for calcium ions was suggested to induce conformational changes in the enzyme loops, making HL more suitable for catalysis. However, we observed that calcium ions do not interact with the enzyme, and its role actually is in modulating the hyaluronan conformation and not in the functional regulation of enzyme.
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9
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Affiliation(s)
- Robert Stern
- Department of Pathology and Comprehensive Cancer Center, School of Medicine, University of California, San Francisco, CA 94143-0511, USA
| | - Mark J. Jedrzejas
- Children’s Hospital Oakland Research Institute, Oakland, CA 94609, USA
- To whom correspondence should be addressed: Children’s Hospital Oakland Research Institute, 5700 Martin Luther King, Jr. Way, Oakland, California 94609, USA, Phone: +1 510-450-7932, Fax +1 510-450-7914, e-mail: , Web: www.chori.org/investigators/jedrzejas.html
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10
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Rigden DJ, Botzki A, Nukui M, Mewbourne RB, Lamani E, Braun S, von Angerer E, Bernhardt G, Dove S, Buschauer A, Jedrzejas MJ. Design of new benzoxazole-2-thione-derived inhibitors of Streptococcus pneumoniae hyaluronan lyase: structure of a complex with a 2-phenylindole. Glycobiology 2006; 16:757-65. [PMID: 16638841 DOI: 10.1093/glycob/cwj116] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The bacterial hyaluronan lyases (Hyals) that degrade hyaluronan, an important component of the extracellular matrix, are involved in microbial spread. Inhibitors of these enzymes are essential in investigation of the role of hyaluronan and Hyal in bacterial infections and constitute a new class of antibiotics against Hyal-producing bacteria. Recently, we identified 1,3-diacetylbenzimidazole-2-thione and related molecules as inhibitors of streptococcal Hyal. One of such compounds, 1-decyl-2-(4-sulfamoyloxyphenyl)-1-indol-6-yl sulfamate, was co-crystallized in a complex with Streptococcus pneumoniae Hyal and its structure elucidated. The resultant X-ray structure demonstrates that this inhibitor fits in the enzymatic active site via interactions resembling the binding mode of the natural hyaluronan substrate. X-ray structural analysis also indicates binding interactions with the catalytic residues and those of a catalytically essential hydrophobic patch. An IC50 value of 11 microM for Hyal from Streptococcus agalactiae (strain 4755) qualifies this phenylindole compound as one of the most potent Hyal inhibitors known to date. The structural data suggested a similar binding mode for N-(3-phenylpropionyl)-benzoxazole-2-thione. This new compound's inhibitory properties were confirmed resulting in discovery of yet another Hyal inhibitor (IC50 of 15 microM). These benzoxazole-2-thiones constitute a new class of inhibitors of bacterial Hyals and are well suited for further optimization of their selectivity, potency, and pharmacokinetic properties.
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Affiliation(s)
- Daniel J Rigden
- Institute of Pharmacy, University of Regensburg, 93040 Regensburg, Germany
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Jedrzejas MJ, Stern R. Structures of vertebrate hyaluronidases and their unique enzymatic mechanism of hydrolysis. Proteins 2006; 61:227-38. [PMID: 16104017 DOI: 10.1002/prot.20592] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Human hyaluronidases (Hyals) are a group of five endo-beta-acetyl-hexosaminidase enzymes, Hyal-1, -2, -3, -4, and PH-20, which degrade hyaluronan using a hydrolytic mechanism of action. Catalysis by these Hyals has been shown to follow a double-displacement scheme. This involves a single Glu residue within the enzyme, the only catalytic residue, as the proton donor (acid). Also involved is a carbonyl group of the hyaluronan (HA) N-acetyl-D-glucosamine as a unique type of nucleophile. Thus the substrate participates in the mechanism of action of its own catalysis. An oxocarbonium ion transition state is postulated, but there is no formation of a covalent enzyme-glycan intermediate, as found in most such reactions. The major domain is catalytic and has a distorted (beta/alpha)8 triose phosphate isomerase (TIM) barrel fold. The C-terminal domain is separated by a peptide linker. Each Hyal has a different C-terminal sequence and structure, the function of which is unknown. These unique C-termini may participate in the additional function(s) associated with these multifunctional enzymes.
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Affiliation(s)
- Mark J Jedrzejas
- Children's Hospital Oakland Research Institute, Oakland, California 94609, USA
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Rigden DJ, Littlejohn JE, Joshi HV, de Groot BL, Jedrzejas MJ. Alternate structural conformations of Streptococcus pneumoniae hyaluronan lyase: insights into enzyme flexibility and underlying molecular mechanism of action. J Mol Biol 2006; 358:1165-78. [PMID: 16569416 DOI: 10.1016/j.jmb.2006.02.066] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2005] [Revised: 02/20/2006] [Accepted: 02/23/2006] [Indexed: 11/26/2022]
Abstract
Streptococcus pneumoniae hyaluronan lyase is a surface enzyme of this Gram-positive bacterium. The enzyme degrades several biologically important, information-rich linear polymeric glycans: hyaluronan, unsulfated chondroitin, and some chondroitin sulfates. This degradation facilitates spreading of bacteria throughout the host tissues and presumably provides energy and a carbon source for pneumococcal cells. Its beta-elimination catalytic mechanism is an acid/base process termed proton acceptance and donation leading to cleavage of beta-1,4 linkages of the substrates. The degradation of hyaluronan occurs in two stages, initial endolytic cuts are followed by processive exolytic cleavage of one disaccharide at a time. In contrast, the degradation of chondroitins is purely endolytic. Structural studies together with flexibility analyses of two streptococcal enzymes, from S.pneumoniae and Streptococcus agalactiae, allowed for insights into this enzyme's molecular mechanism. Here, two new X-ray crystal structures of the pneumococcal enzyme in novel conformations are reported. These new conformations, complemented by molecular dynamics simulation results, directly confirm the predicted domain motions presumed to facilitate the processive degradative process. One of these new structures resembles the S.agalactiae enzyme conformation, and provides evidence of a uniform mechanistic/dynamic behavior of this protein across different bacteria.
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Affiliation(s)
- Daniel J Rigden
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
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Rigden DJ, Jedrzejas MJ. Structures of Streptococcus pneumoniae Hyaluronate Lyase in Complex with Chondroitin and Chondroitin Sulfate Disaccharides. J Biol Chem 2003; 278:50596-606. [PMID: 14523022 DOI: 10.1074/jbc.m307596200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Streptococcus pneumoniae hyaluronate lyase is a surface enzyme of this Gram-positive bacterium. The enzyme degrades hyaluronan and chondroitin/chondroitin sulfates by cleaving the beta1,4-glycosidic linkage between the glycan units of these polymeric substrates. This degradation helps spreading of this bacterial organism throughout the host tissues and facilitates the disease process caused by pneumococci. The mechanism of this degradative process is based on beta-elimination, is termed proton acceptance and donation, and involves selected residues of a well defined catalytic site of the enzyme. The degradation of hyaluronan alone is thought to proceed through a processive mode of action. The structures of complexes between the enzyme and chondroitin as well as chondroitin sulfate disaccharides allowed for the first detailed insights into these interactions and the mechanism of action on chondroitins. This degradation of chondroitin/chondroitin sulfates is nonprocessive and is selective for the chondroitin sulfates only with certain sulfation patterns. Chondroitin sulfation at the 4-position on the nonreducing site of the linkage to be cleaved or 2-sulfation prevent degradation due to steric clashes with the enzyme. Evolutionary studies suggest that hyaluronate lyases evolved from chondroitin lyases and still retained chondroitin/chondroitin sulfate degradation abilities while being specialized in the degradation of hyaluronan. The more efficient processive degradation mechanism has come to be preferred for the unsulfated substrate hyaluronan.
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Affiliation(s)
- Daniel J Rigden
- Children's Hospital Oakland Research Institute, Oakland, California 94609, USA
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