1
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Chen Q, Zhou J, Yang Z, Guo J, Liu Z, Sun X, Jiang Q, Fang L, Wang D, Xiao S. An intermolecular salt bridge linking substrate binding and P1 substrate specificity switch of arterivirus 3C-like proteases. Comput Struct Biotechnol J 2022; 20:3409-3421. [PMID: 35832618 PMCID: PMC9271976 DOI: 10.1016/j.csbj.2022.06.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 06/26/2022] [Accepted: 06/27/2022] [Indexed: 11/26/2022] Open
Abstract
Equine arteritis virus (EAV) and porcine reproductive and respiratory syndrome virus (PRRSV) represent two members of the family Arteriviridae and pose a major threat to the equine- and swine-breeding industries throughout the world. Previously, we and others demonstrated that PRRSV 3C-like protease (3CLpro) had very high glutamic acid (Glu)-specificity at the P1 position (P1-Glu). Comparably, EAV 3CLpro exhibited recognition of both Glu and glutamine (Gln) at the P1 position. However, the underlying mechanisms of the P1 substrate specificity shift of arterivirus 3CLpro remain unclear. We systematically screened the specific amino acids in the S1 subsite of arterivirus 3CLpro using a cyclized luciferase-based biosensor and identified Gly116, His133 and Ser136 (using PRRSV 3CLpro numbering) are important for recognition of P1-Glu, whereas Ser136 is nonessential for recognition of P1-Gln. Molecular dynamics simulations and biochemical experiments highlighted that the PRRSV 3CLpro and EAV 3CLpro formed distinct S1 subsites for the P1 substrate specificity switch. Mechanistically, a specific intermolecular salt bridge between PRRSV 3CLpro and substrate P1-Glu (Lys138/P1-Glu) are invaluable for high Glu-specificity at the P1 position, and the exchange of K138T (salt bridge interruption, from PRRSV to EAV) shifted the specificity of PRRSV 3CLpro toward P1-Gln. In turn, the T139K exchange of EAV 3CLpro showed a noticeable shift in substrate specificity, such that substrates containing P1-Glu are likely to be recognized more efficiently. These findings identify an evolutionarily accessible mechanism for disrupting or reorganizing salt bridge with only a single mutation of arterivirus 3CLpro to trigger a substrate specificity switch.
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Affiliation(s)
- Qian Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Junwei Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Zhixiang Yang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Jiahui Guo
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Zimin Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Xinyi Sun
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Qingshi Jiang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Liurong Fang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Dang Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Shaobo Xiao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.,Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
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2
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Manne K, Narayana SVL. Structural insights into the role of the N-terminus in the activation and function of extracellular serine protease from Staphylococcus epidermidis. Acta Crystallogr D Struct Biol 2020; 76:28-40. [PMID: 31909741 PMCID: PMC6939437 DOI: 10.1107/s2059798319015055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/07/2019] [Indexed: 11/10/2022] Open
Abstract
Extracellular serine protease (Esp) from Staphylococcus epidermidis is a glutamyl endopeptidase that inhibits the growth and formation of S. aureus biofilms. Previously, crystal structures of the matured and active Esp have been determined. Interestingly, many of the staphylococcal glutamyl endopeptidase zymogens, including V8 from Staphylococcus aureus and Esp from S. epidermidis, contain unusually long pro-peptide segments; however, their function is not known. With the aim of elucidating the function of these pro-peptide segments, crystal structures of the Esp zymogen (Pro-Esp) and its variants were determined. It was observed that the N-terminus of the Pro-Esp crystal structure is flexible and is not associated with the main body of the enzyme, unlike in the known active Esp structure. In addition, the loops that border the putative substrate-binding pocket of Pro-Esp are flexible and disordered; the structural components that are responsible for enzyme specificity and efficiency in serine proteases are disordered in Pro-Esp. However, the N-terminal locked Pro-Esp variants exhibit a rigid substrate-binding pocket similar to the active Esp structure and regain activity. These structural studies highlight the role of the N-terminus in stabilizing the structural components responsible for the activity and specificity of staphylococcal glutamyl endopeptidases.
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Affiliation(s)
- Kartik Manne
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Sthanam V. L. Narayana
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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3
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Demidyuk I, Chukhontseva K, Kostrov S. Glutamyl Endopeptidases: The Puzzle of Substrate Specificity. Acta Naturae 2017; 9:17-33. [PMID: 28740724 PMCID: PMC5508998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Indexed: 11/24/2022] Open
Abstract
Glutamyl endopeptidases (GEPases) are chymotrypsin-like enzymes that preferentially cleave the peptide bonds of the α-carboxyl groups of glutamic acid. Despite the many years of research, the structural determinants underlying the strong substrate specificity of GEPases still remain unclear. In this review, data concerning the molecular mechanisms that determine the substrate preference of GEPases is generalized. In addition, the biological functions of and modern trends in the research into these enzymes are outlined.
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Affiliation(s)
- I.V. Demidyuk
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq., 2, Moscow, 123182, Russia
| | - K.N. Chukhontseva
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq., 2, Moscow, 123182, Russia
| | - S.V. Kostrov
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq., 2, Moscow, 123182, Russia
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4
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Autocatalytic activation of a thermostable glutamyl endopeptidase capable of hydrolyzing proteins at high temperatures. Appl Microbiol Biotechnol 2016; 100:10429-10441. [PMID: 27377749 DOI: 10.1007/s00253-016-7697-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/16/2016] [Accepted: 06/19/2016] [Indexed: 01/27/2023]
Abstract
Glutamyl endopeptidases (GSEs) specifically hydrolyze peptide bonds formed by α-carboxyl groups of Glu and Asp residues. We cloned the gene for a thermophilic GSE (designated TS-GSE) from Thermoactinomyces sp. CDF. A proform of TS-GSE that contained a 61-amino acid N-terminal propeptide and a 218-amino acid mature domain was produced in Escherichia coli. We found that the proform possessed two processing sites and was capable of autocatalytic activation via multiple pathways. The N-terminal propeptide could be autoprocessed at the Glu-1-Ser1 bond to directly generate the mature enzyme. It could also be autoprocessed at the Glu-12-Lys-11 bond to yield an intermediate, which was then converted into the mature form after removal of the remaining part of the propeptide. The segment surrounding the two processing sites was flexible, which allowed the proform and the intermediate form to be trans-processed into the mature form by either active TS-GSE or heterogeneous proteases. Deletion analysis revealed that the N-terminal propeptide is important for the correct folding and maturation of TS-GSE. The propeptide, even its last 11-amino acid peptide segment, could inhibit the activity of its cognate mature domain. The mature TS-GSE displayed a temperature optimum of 85 °C and retained approximately 90 % of its original activity after incubation at 70 °C for 6 h, representing the most thermostable GSE reported to date. Mutational analysis suggested that the disulfide bonds Cys32-Cys48 and Cys180-Cys183 cumulatively contributed to the thermostability of TS-GSE.
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5
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Velishaeva NS, Gasanov EV, Gromova TI, Demidiuk IV. [Effect of a modification of the processing site of Bacillus intermedius glutamyl endopeptidase on the production of active enzyme by Bacillus subtilis cells]. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2008; 34:786-91. [PMID: 19088752 DOI: 10.1134/s1068162008060095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A site-directed modification in position P1 of the processing site of Bacillus intermedius glutamyl endopeptidase was carried out. Variants of the protease gene were obtained that correspond to the protein with an Ala, Asn, Ser, or Glu residue in this position substituted for the Lys residue. The residue in the P1 position of the processing site was shown to affect substantially the production of the active enzyme; however, none of the mutations leads to the complete termination of active protein production by cells.
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Affiliation(s)
- N S Velishaeva
- Institute of Molecular Genetics, Russian Academy of Sciences, pl. Akademika Kurchatova 2, Moscow, 123182 Russia
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6
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Nair S, Gayathri P, Murthy M, Savithri H. Stacking interactions of W271 and H275 of SeMV serine protease with W43 of natively unfolded VPg confer catalytic activity to protease. Virology 2008; 382:83-90. [DOI: 10.1016/j.virol.2008.08.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Revised: 08/10/2008] [Accepted: 08/15/2008] [Indexed: 11/24/2022]
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7
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Gasanov E, Demidyuk I, Shubin A, Kozlovskiy V, Leonova O, Kostrov S. Hetero- and auto-activation of recombinant glutamyl endopeptidase from Bacillus intermedius. Protein Eng Des Sel 2008; 21:653-8. [DOI: 10.1093/protein/gzn044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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8
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Dubin G, Stec-Niemczyk J, Kisielewska M, Pustelny K, Popowicz GM, Bista M, Kantyka T, Boulware KT, Stennicke HR, Czarna A, Phopaisarn M, Daugherty PS, Thøgersen IB, Enghild JJ, Thornberry N, Dubin A, Potempa J. Enzymatic activity of the Staphylococcus aureus SplB serine protease is induced by substrates containing the sequence Trp-Glu-Leu-Gln. J Mol Biol 2008; 379:343-56. [PMID: 18448121 DOI: 10.1016/j.jmb.2008.03.059] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 03/21/2008] [Accepted: 03/25/2008] [Indexed: 12/18/2022]
Abstract
Proteases are of significant importance for the virulence of Staphylococcus aureus. Nevertheless, their subset, the serine protease-like proteins, remains poorly characterized. Here presented is an investigation of SplB protease catalytic activity revealing that the enzyme possesses exquisite specificity and only cleaves efficiently after the sequence Trp-Glu-Leu-Gln. To understand the molecular basis for such selectivity, we solved the three-dimensional structure of SplB to 1.8 A. Modeling of substrate binding to the protease demonstrated that selectivity relies in part on a canonical specificity pockets-based mechanism. Significantly, the conformation of residues that ordinarily form the oxyanion hole, an essential structural element of the catalytic machinery of serine proteases, is not canonical in the SplB structure. We postulate that within SplB, the oxyanion hole is only formed upon docking of a substrate containing the consensus sequence motif. It is suggested that this unusual activation mechanism is used in parallel with classical determinants to further limit enzyme specificity. Finally, to guide future development, we attempt to point at likely physiological substrates and thus the role of SplB in staphylococcal physiology.
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Affiliation(s)
- Grzegorz Dubin
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland.
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9
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Trachuk LA, Shcheglov AS, Milgotina EI, Chestukhina GG. In vitro maturation pathway of a glutamyl endopeptidase precursor from Bacillus licheniformis. Biochimie 2005; 87:529-37. [PMID: 15935278 DOI: 10.1016/j.biochi.2005.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Accepted: 02/10/2005] [Indexed: 11/22/2022]
Abstract
A gene encoding of glutamyl-specific endopeptidase precursor from Bacillus licheniformis has been cloned in Escherichia coli cells. The recombinant protein was expressed and accumulated as cytoplasmic insoluble inclusion bodies. Washed inclusion bodies were solubilized in 6 M guanidine-HCL in the presence of reducing agent. The following precursor renaturation was performed by fast frequent dilution method. The highest yield of the refolded protein was achieved at pH value of 8.5 and 4 degrees C. The renaturation process was accompanied by a gradual splitting of Glu(-48)/Thr(-47) and Glu(-13)/Lys(-12) peptide bonds. A 26-kDa protein proved to be an end product of in vitro renaturation. The mature glutamyl endopeptidase with a molecular mass of 25 kDa was obtained after a limited proteolysis of the 26-kDa protein was performed by subtilisin or trypsin. The 26-kDa protein was purified by gel filtration on a Superdex 75 column. Comparative characteristics of the thermal stability and catalytic properties of the 26-kDa and 25-kDa proteins showed that complete cleavage of the N-terminal pro-peptide by exogenous proteinase is necessary for a final packing and activation of the B. licheniformis glutamyl endopeptidase.
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Affiliation(s)
- L A Trachuk
- Laboratory of Protein Chemistry, Institute of Genetics and Selection of Industrial Microorganisms, 1st Dorozhny, 1, Moscow, 113545, Russia.
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10
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Najmanová L, Janata J, Kopecký J, Spízek J. Spore-specific modification of DNA-dependent RNA polymerase alpha subunit in streptomycetes--a new model of transcription regulation. Folia Microbiol (Praha) 2004; 48:573-9. [PMID: 14976711 DOI: 10.1007/bf02993461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
At the very beginning of spore germination in streptomycetes the full-length alpha subunit of DNA-dependent RNA polymerase is shortened from its C-terminus. The C-terminal domain of the protein is required for binding of DNA and transcription regulators but its regulatory role in streptomycetes was not extensively studied. Comparison of the sequences of E. coli and S. coelicolor RNA polymerase alpha subunit (RNAP alpha) C-terminal domains reveals that the majority of amino acid residues responsible for the interaction with transcription regulators is conserved in both microorganisms. The spore specific modification of streptomycete RNAP alpha could thus have its regulatory role. The nature of the proteolytic enzyme, responsible for the RNAP alpha cleavage is discussed.
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Affiliation(s)
- L Najmanová
- Institute of Microbiology, Academy of Sciences of the Czech Republic, 142 20 Prague, Czechia
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11
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Barrette-Ng IH, Ng KKS, Mark BL, Van Aken D, Cherney MM, Garen C, Kolodenko Y, Gorbalenya AE, Snijder EJ, James MNG. Structure of arterivirus nsp4. The smallest chymotrypsin-like proteinase with an alpha/beta C-terminal extension and alternate conformations of the oxyanion hole. J Biol Chem 2002; 277:39960-6. [PMID: 12163505 DOI: 10.1074/jbc.m206978200] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Arteriviruses are enveloped, positive-stranded RNA viruses and include pathogens of major economic concern to the swine- and horse-breeding industries. The arterivirus replicase gene encodes two large precursor polyproteins that are processed by the viral main proteinase nonstructural protein 4 (nsp4). The three-dimensional structure of the 21-kDa nsp4 from the arterivirus prototype equine arteritis virus has been determined to 2.0 A resolution. Nsp4 adopts the smallest known chymotrypsin-like fold with a canonical catalytic triad of Ser-120, His-39, and Asp-65, as well as a novel alpha/beta C-terminal extension domain that may play a role in mediating protein-protein interactions. In different copies of nsp4 in the asymmetric unit, the oxyanion hole adopts either a collapsed inactive conformation or the standard active conformation, which may be a novel way of regulating proteolytic activity.
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Affiliation(s)
- Isabelle H Barrette-Ng
- Canadian Institutes for Health Research Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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12
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Stennicke HR, Renatus M, Meldal M, Salvesen GS. Internally quenched fluorescent peptide substrates disclose the subsite preferences of human caspases 1, 3, 6, 7 and 8. Biochem J 2000; 350 Pt 2:563-8. [PMID: 10947972 PMCID: PMC1221285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Subsite interactions are considered to define the stringent specificity of proteases for their natural substrates. To probe this issue in the proteolytic pathways leading to apoptosis we have examined the P(4), P(1) and P(1)' subsite preferences of human caspases 1, 3, 6, 7 and 8, using internally quenched fluorescent peptide substrates containing o-aminobenzoyl (also known as anthranilic acid) and 3-nitro-tyrosine. Previous work has demonstrated the importance of the S(4) subsite in directing specificity within the caspase family. Here we demonstrate the influence of the S(1) and S(1)' subsites that flank the scissile peptide bond. The S(1) subsite, the major specificity-determining site of the caspases, demonstrates tremendous selectivity, with a 20000-fold preference for cleaving substrates containing aspartic acid over glutamic acid at this position. Thus caspases are among the most selective of known endopeptidases. We find that the caspases show an unexpected degree of discrimination in the P(1)' position, with a general preference for small amino acid residues such as alanine, glycine and serine, with glycine being the preferred substituent. Large aromatic residues are also surprisingly well-tolerated, but charged residues are prohibited. While this describes the general order of P(1)' subsite preferences within the caspase family, there are some differences in individual profiles, with caspase-3 being particularly promiscuous. Overall, the subsite preferences can be used to predict natural substrates, but in certain cases the cleavage site within a presumed natural substrate cannot be predicted by looking for the preferred peptide cleavage sites. In the latter case we conclude that second-site interactions may overcome otherwise sub-optimal cleavage sequences.
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Affiliation(s)
- H R Stennicke
- Program for Apoptosis & Cell Death Research, The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
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13
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Papageorgiou AC, Plano LR, Collins CM, Acharya KR. Structural similarities and differences in Staphylococcus aureus exfoliative toxins A and B as revealed by their crystal structures. Protein Sci 2000; 9:610-8. [PMID: 10752623 PMCID: PMC2144578 DOI: 10.1110/ps.9.3.610] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Staphylococcal aureus epidermolytic toxins (ETs) A and B are responsible for the induction of staphylococcal scalded skin syndrome, a disease of neonates and young children. The clinical features of this syndrome vary from localized blisters to severe exfoliation affecting most of the body surface. Comparison of the crystal structures of two subtypes of ETs-rETA (at 2.0 A resolution), rETB (at 2.8 A resolution), and an active site variant of rETA, Ser195Ala at 2.0 A resolution has demonstrated that their overall topology resembles that of a "trypsin-like" serine protease, but with significant differences at the N- and C-termini and loop regions. The details of the catalytic site in both ET structures are very similar to those in glutamate-specific serine proteases, suggesting a common catalytic mechanism. However, the "oxyanion hole," which is part of the catalytic sites of glutamate specific serine proteases, is in the closed or inactive conformation for rETA, yet in the open or active conformation for rETB. The ETs contain a unique amphipathic helix at the N-terminus, and it appears to be involved in optimizing the conformation of the catalytic site residues. Determination of the structure of the rETA catalytic site variant, Ser195Ala, showed no significant perturbation at the active site, establishing that the loss of biological and esterolytic activity can be attributed solely to disruption of the catalytic serine residue. Finally, the crystal structure of ETs, together with biochemical data and mutagenesis studies, strongly confirms the classification of these molecules as "serine proteases" rather than "superantigens."
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Affiliation(s)
- A C Papageorgiou
- Department of Biology and Biochemistry, University of Bath, United Kingdom
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14
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Czapinska H, Otlewski J. Structural and energetic determinants of the S1-site specificity in serine proteases. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 260:571-95. [PMID: 10102985 DOI: 10.1046/j.1432-1327.1999.00160.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In recent years the number of determined three-dimensional structures of serine proteases that are accompanied by detailed mutational studies has grown rapidly. In particular, spatial structures have been described for enzymes involved in processes of critical medical significance, often related to severe pathophysiological diseases. There has also been significant progress in the understanding of the structural grounds for the substrate specificity of serine proteases. This review is concerned mainly with primary structural determinants of the S1 specificity, the crucial component of substrate selectivity, often in relation to more distant specificity elements, which cooperatively influence the S1 site.
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Affiliation(s)
- H Czapinska
- Institute of Biochemistry, University of Wroclaw, Poland
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15
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Rebrikov DV, Akimkina TV, Shevelev AB, Demidyuk IV, Bushueva AM, Kostrov SV, Chestukhina GG, Stepanov VM. Bacillus intermedius glutamyl endopeptidase. Molecular cloning and nucleotide sequence of the structural gene. JOURNAL OF PROTEIN CHEMISTRY 1999; 18:21-7. [PMID: 10071925 DOI: 10.1023/a:1020639230985] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The glutamyl endopeptidase gene of Bacillus intermedius was cloned from a genomic library expressed in Bacillus subtilis and sequenced (EMBL accession number Y15136). The encoded preproenzyme contains 303 amino acid residues; the mature 23-kDa enzyme consists of 215 residues. The mature enzyme reveals 38% of identical residues when aligned with the glutamyl endopeptidase from Bacillus licheniformis, whereas only five invariant residues were found among all known glutamyl endopeptidases. The amino acid residues that form the catalytic triad (H47, D98, and S171) as well as H186 participating in the binding of the substrate carboxyl group were identified. It seems that the structural elements responsible for the function of glutamyl endopeptidases from various sources are highly variable.
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Affiliation(s)
- D V Rebrikov
- Molecular Biology Department, Biological Faculty, Moscow State University, Russia
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16
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Sørensen SB, Breddam K. The specificity of carboxypeptidase Y may be altered by changing the hydrophobicity of the S'1 binding pocket. Protein Sci 1997; 6:2227-32. [PMID: 9336845 PMCID: PMC2143575 DOI: 10.1002/pro.5560061017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The S'1 binding pocket of carboxypeptidase Y is hydrophobic, spacious, and open to solvent, and the enzyme exhibits a preference for hydrophobic P'1 amino acid residues. Leu272 and Ser297, situated at the rim of the pocket, and Leu267, slightly further away, have been substituted by site-directed mutagenesis. The mutant enzymes have been characterized kinetically with respect to their P'1 substrate preferences using the substrate series FA-Ala-Xaa-OH (Xaa = Leu, Glu, Lys, or Arg) and FA-Phe-Xaa-OH (Xaa = Ala, Val, or Leu). The results reveal that hydrophobic P'1 residues bind in the vicinity of residue 272 while positively charged P'1 residues interact with Ser297. Introduction of Asp or Glu at position 267 greatly reduced the activity toward hydrophobic P'1 residues (Leu) and increased the activity two- to three-fold for the hydrolysis of substrates with Lys or Arg in P'1. Negatively charged substituents at position 272 reduced the activity toward hydrophobic P'1 residues even more, but without increasing the activity toward positively charged P'1 residues. The mutant enzyme L267D + L272D was found to have a preference for substrates with C-terminal basic amino acid residues. The opposite situation, where the positively charged Lys or Arg were introduced at one of the positions 267, 272, or 297, did not increase the rather low activity toward substrates with Glu in the P'1 position but greatly reduced the activity toward substrates with C-terminal Lys or Arg due to electrostatic repulsion. The characterized mutant enzymes exhibit various specificities, which may be useful in C-terminal amino acid sequence determinations.
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Affiliation(s)
- S B Sørensen
- Carlsberg Laboratory, Department of Chemistry, Copenhagen Valby, Denmark.
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17
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Cavarelli J, Prévost G, Bourguet W, Moulinier L, Chevrier B, Delagoutte B, Bilwes A, Mourey L, Rifai S, Piémont Y, Moras D. The structure of Staphylococcus aureus epidermolytic toxin A, an atypic serine protease, at 1.7 A resolution. Structure 1997; 5:813-24. [PMID: 9261066 DOI: 10.1016/s0969-2126(97)00235-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Staphylococcal epidermolytic toxins A and B (ETA and ETB) are responsible for the staphylococcal scalded skin syndrome of newborn and young infants; this condition can appear just a few hours after birth. These toxins cause the disorganization and disruption of the region between the stratum spinosum and the stratum granulosum--two of the three cellular layers constituting the epidermis. The physiological substrate of ETA is not known and, consequently, its mode of action in vivo remains an unanswered question. Determination of the structure of ETA and its comparison with other serine proteases may reveal insights into ETA's catalytic mechanism. RESULTS The crystal structure of staphylococcal ETA has been determined by multiple isomorphous replacement and refined at 1.7 A resolution with a crystallographic R factor of 0.184. The structure of ETA reveals it to be a new and unique member of the trypsin-like serine protease family. In contrast to other serine protease folds, ETA can be characterized by ETA-specific surface loops, a lack of cysteine bridges, an oxyanion hole which is not preformed, an S1 specific pocket designed for a negatively charged amino acid and an ETA-specific specific N-terminal helix which is shown to be crucial for substrate hydrolysis. CONCLUSIONS Despite very low sequence homology between ETA and other trypsin-like serine proteases, the ETA crystal structure, together with biochemical data and site-directed mutagenesis studies, strongly confirms the classification of ETA in the Glu-endopeptidase family. Direct links can be made between the protease architecture of ETA and its biological activity.
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Affiliation(s)
- J Cavarelli
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, Illkirch, France.
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