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Jiang X, Shu H, Feng S, Wang P, Zhang Z, Wang N. A Hadal Streptomyces-Derived Echinocandin Acylase Discovered through the Prioritization of Protein Families. Mar Drugs 2024; 22:212. [PMID: 38786603 PMCID: PMC11122479 DOI: 10.3390/md22050212] [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: 04/04/2024] [Revised: 04/28/2024] [Accepted: 05/04/2024] [Indexed: 05/25/2024] Open
Abstract
Naturally occurring echinocandin B and FR901379 are potent antifungal lipopeptides featuring a cyclic hexapeptide nucleus and a fatty acid side chain. They are the parent compounds of echinocandin drugs for the treatment of severe fungal infections caused by the Candida and Aspergilla species. To minimize hemolytic toxicity, the native fatty acid side chains in these drug molecules are replaced with designer acyl side chains. The deacylation of the N-acyl side chain is, therefore, a crucial step for the development and manufacturing of echinocandin-type antibiotics. Echinocandin E (ECE) is a novel echinocandin congener with enhanced stability generated via the engineering of the biosynthetic machinery of echinocandin B (ECB). In the present study, we report the discovery of the first echinocandin E acylase (ECEA) using the enzyme similarity tool (EST) for enzymatic function mining across protein families. ECEA is derived from Streptomyces sp. SY1965 isolated from a sediment collected from the Mariana Trench. It was cloned and heterologously expressed in S. lividans TK24. The resultant TKecea66 strain showed efficient cleavage activity of the acyl side chain of ECE, showing promising applications in the development of novel echinocandin-type therapeutics. Our results also provide a showcase for harnessing the essentially untapped biodiversity from the hadal ecosystems for the discovery of functional molecules.
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Affiliation(s)
- Xuejian Jiang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Hongjun Shu
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Shuting Feng
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Pinmei Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
- Hainan Institute of Zhejiang University, Sanya 572025, China
| | - Zhizhen Zhang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
| | - Nan Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (X.J.); (H.S.); (S.F.); (P.W.); (Z.Z.)
- Hainan Institute of Zhejiang University, Sanya 572025, China
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2
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Cephalosporins as key lead generation beta-lactam antibiotics. Appl Microbiol Biotechnol 2022; 106:8007-8020. [DOI: 10.1007/s00253-022-12272-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Abstract
Antibiotics are antibacterial compounds that interfere with bacterial growth, without harming the infected eukaryotic host. Among the clinical agents, beta-lactams play a major role in treating infected humans and animals. However, the ever-increasing antibiotic resistance crisis is forcing the pharmaceutical industry to search for new antibacterial drugs to combat a range of current and potential multi-resistant bacterial pathogens. In this review, we provide an overview of the development, innovation, and current status of therapeutic applications for beta-lactams with a focus on semi-synthetic cephalosporins. Cephalosporin C (CPC), which is a natural secondary metabolite from the filamentous fungus Acremonium chrysogenum, plays a major and demanding role in both producing modern antibiotics and developing new ones. CPC serves as a core compound for producing semi-synthetic cephalosporins that can control infections with different resistance mechanisms. We therefore summarize our latest knowledge about the CPC biosynthetic pathway and its regulation in the fungal host. Finally, we describe how CPC serves as a key lead generation source for the in vitro and better, in vivo synthesis of 7-aminocephalosporanic acid (7-ACA), the major core compound for the pharmaceutical synthesis of current and future semi-synthetic cephalosporins.
Key points
•Latest literature on cephalosporin generations
•Biotechnical production of cephalosporins
•In vivo production of 7-ACA
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Linhorst A, Lübke T. The Human Ntn-Hydrolase Superfamily: Structure, Functions and Perspectives. Cells 2022; 11:cells11101592. [PMID: 35626629 PMCID: PMC9140057 DOI: 10.3390/cells11101592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 01/27/2023] Open
Abstract
N-terminal nucleophile (Ntn)-hydrolases catalyze the cleavage of amide bonds in a variety of macromolecules, including the peptide bond in proteins, the amide bond in N-linked protein glycosylation, and the amide bond linking a fatty acid to sphingosine in complex sphingolipids. Ntn-hydrolases are all sharing two common hallmarks: Firstly, the enzymes are synthesized as inactive precursors that undergo auto-proteolytic self-activation, which, as a consequence, reveals the active site nucleophile at the newly formed N-terminus. Secondly, all Ntn-hydrolases share a structural consistent αββα-fold, notwithstanding the total lack of amino acid sequence homology. In humans, five subclasses of the Ntn-superfamily have been identified so far, comprising relevant members such as the catalytic active subunits of the proteasome or a number of lysosomal hydrolases, which are often associated with lysosomal storage diseases. This review gives an updated overview on the structural, functional, and (patho-)physiological characteristics of human Ntn-hydrolases, in particular.
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A Straightforward Approach to Synthesize 7-Aminocephalosporanic Acid In Vivo in the Cephalosporin C Producer Acremonium chrysogenum. J Fungi (Basel) 2022; 8:jof8050450. [PMID: 35628706 PMCID: PMC9144927 DOI: 10.3390/jof8050450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/22/2022] [Accepted: 04/23/2022] [Indexed: 12/04/2022] Open
Abstract
The pharmaceutical industry has developed various highly effective semi-synthetic cephalosporins, which are generated by modifying the side chains of the core molecule 7-aminocephalosporanic acid (7-ACA). In industrial productions, the 7-ACA nucleus is obtained in vitro from cephalosporin C (CPC) by chemical or enzymatic processes, which are waste intensive and associated with high production costs. Here, we used a transgenic in vivo approach to express bacterial genes for cephalosporin C acylase (CCA) in the CPC producer Acremonium chrysogenum. Western blot and mass spectrometry analyses verified that the heterologous enzymes are processed into α- and β-subunits in the fungal cell. Extensive HPLC analysis detected substrates and products of CCAs in both fungal mycelia and culture supernatants, with the highest amount of 7-ACA found in the latter. Using different incubation times, temperatures, and pH values, we explored the optimal conditions for the active bacterial acylase to convert CPC into 7-ACA in the culture supernatant. We calculated that the best transgenic fungal strains exhibit a one-step conversion rate of the bacterial acylase of 30%. Our findings can be considered a remarkable contribution to supporting future pharmaceutical manufacturing processes with reduced production costs.
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Murugayah SA, Evans GB, Tyndall JDA, Gerth ML. A single point mutation converts a glutaryl-7-aminocephalosporanic acid acylase into an N-acyl-homoserine lactone acylase. Biotechnol Lett 2021; 43:1467-1473. [PMID: 33891232 PMCID: PMC8197700 DOI: 10.1007/s10529-021-03135-9] [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: 01/12/2021] [Accepted: 04/15/2021] [Indexed: 11/25/2022]
Abstract
Objective To change the specificity of a glutaryl-7-aminocephalosporanic acid acylase (GCA) towards N-acyl homoserine lactones (AHLs; quorum sensing signalling molecules) by site-directed mutagenesis. Results Seven residues were identified by analysis of existing crystal structures as potential determinants of substrate specificity. Site-saturation mutagenesis libraries were created for each of the seven selected positions. High-throughput activity screening of each library identified two variants—Arg255Ala, Arg255Gly—with new activities towards N-acyl homoserine lactone substrates. Structural modelling of the Arg255Gly mutation suggests that the smaller side-chain of glycine (as compared to arginine in the wild-type enzyme) avoids a key clash with the acyl group of the N-acyl homoserine lactone substrate. Conclusions Mutation of a single amino acid residue successfully converted a GCA (with no detectable activity against AHLs) into an AHL acylase. This approach may be useful for further engineering of ‘quorum quenching’ enzymes. Supplementary Information The online version contains supplementary material available at 10.1007/s10529-021-03135-9.
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Affiliation(s)
| | - Gary B Evans
- The Ferrier Research Institute, Victoria University of Wellington, Petone, 5046, New Zealand
| | - Joel D A Tyndall
- School of Pharmacy, University of Otago, Dunedin, 9054, New Zealand
| | - Monica L Gerth
- Department of Biochemistry, University of Otago, Dunedin, 9054, New Zealand. .,School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand.
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Saini M, Kashyap A, Bindal S, Saini K, Gupta R. Bacterial Gamma-Glutamyl Transpeptidase, an Emerging Biocatalyst: Insights Into Structure-Function Relationship and Its Biotechnological Applications. Front Microbiol 2021; 12:641251. [PMID: 33897647 PMCID: PMC8062742 DOI: 10.3389/fmicb.2021.641251] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 02/15/2021] [Indexed: 12/16/2022] Open
Abstract
Gamma-glutamyl transpeptidase (GGT) enzyme is ubiquitously present in all life forms and plays a variety of roles in diverse organisms. Higher eukaryotes mainly utilize GGT for glutathione degradation, and mammalian GGTs have implications in many physiological disorders also. GGTs from unicellular prokaryotes serve different physiological functions in Gram-positive and Gram-negative bacteria. In the present review, the physiological significance of bacterial GGTs has been discussed categorizing GGTs from Gram-negative bacteria like Escherichia coli as glutathione degraders and from pathogenic species like Helicobacter pylori as virulence factors. Gram-positive bacilli, however, are considered separately as poly-γ-glutamic acid (PGA) degraders. The structure-function relationship of the GGT is also discussed mainly focusing on the crystallization of bacterial GGTs along with functional characterization of conserved regions by site-directed mutagenesis that unravels molecular aspects of autoprocessing and catalysis. Only a few crystal structures have been deciphered so far. Further, different reports on heterologous expression of bacterial GGTs in E. coli and Bacillus subtilis as hosts have been presented in a table pointing toward the lack of fermentation studies for large-scale production. Physicochemical properties of bacterial GGTs have also been described, followed by a detailed discussion on various applications of bacterial GGTs in different biotechnological sectors. This review emphasizes the potential of bacterial GGTs as an industrial biocatalyst relevant to the current switch toward green chemistry.
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Affiliation(s)
| | | | | | | | - Rani Gupta
- Department of Microbiology, University of Delhi South Campus, New Delhi, India
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7
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Fang Z, Sun D, Gao J, Guo M, Sun L, Wang Y, Lıu Y, Wang R, Deng Q, Xu D, Gooneratne R. An Acylase from Shewanella Putrefaciens Presents a Vibrio Parahaemolyticus Acylhomoserine Lactone-Degrading Activity and Exhibits Temperature-, Ph- and Metal-Dependences. ACTA ALIMENTARIA 2020. [DOI: 10.1556/066.2020.49.4.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Shewanella putrefaciens supernatant was found to increase the virulence factors of Vibrio parahaemolyticus by efficiently degrading its acylhomoserine lactone (AHL). To further reveal the regulation mechanism and its key degrading enzyme, a potential AHL-degrading enzyme acylase (Aac) from S. putrefaciens was cloned, and the influences of temperature, pH, protein modifiers, and metals on Aac were tested. Aac was significantly influenced by temperature and pH, and exhibited the highest AHL-degrading activity at temperatures of 37 °C and pH of 8. Mg2+ and Fe2+ can further increase the AHL-degrading activity. 10 mM EDTA inhibited its activity possibly by chelating the co-factors (metals) required for Aac activity. Tryptophan and arginine were identified as key components for Aac activity that are critical to its AHL-degrading activity. This study provides useful information on Aac and for V. parahaemolyticus control.
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Affiliation(s)
- Z. Fang
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - D. Sun
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - J. Gao
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - M. Guo
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - L. Sun
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - Y. Wang
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - Y. Lıu
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - R. Wang
- bCollege of Food Science and Engineering, Lingnan Normal University, Zhanjiang, 524048, China
| | - Q. Deng
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - D. Xu
- aCollege of Food Science and Technology, Guangdong Ocean University, Zhanjiang, 524048, China
| | - R. Gooneratne
- cDepartment of Wine, Food and Molecular Biosciences, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
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8
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Modelling of substrate access and substrate binding to cephalosporin acylases. Sci Rep 2019; 9:12402. [PMID: 31455800 PMCID: PMC6712217 DOI: 10.1038/s41598-019-48849-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 08/14/2019] [Indexed: 01/16/2023] Open
Abstract
Semisynthetic cephalosporins are widely used antibiotics currently produced by different chemical steps under harsh conditions, which results in a considerable amount of toxic waste. Biocatalytic synthesis by the cephalosporin acylase from Pseudomonas sp. strain N176 is a promising alternative. Despite intensive engineering of the enzyme, the catalytic activity is still too low for a commercially viable process. To identify the bottlenecks which limit the success of protein engineering efforts, a series of MD simulations was performed to study for two acylase variants (WT, M6) the access of the substrate cephalosporin C from the bulk to the active site and the stability of the enzyme-substrate complex. In both variants, cephalosporin C was binding to a non-productive substrate binding site (E86α, S369β, S460β) at the entrance to the binding pocket, preventing substrate access. A second non-productive binding site (G372β, W376β, L457β) was identified within the binding pocket, which competes with the active site for substrate binding. Noteworthy, substrate binding to the protein surface followed a Langmuir model resulting in binding constants K = 7.4 and 9.2 mM for WT and M6, respectively, which were similar to the experimentally determined Michaelis constants KM = 11.0 and 8.1 mM, respectively.
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9
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Modeling and molecular dynamics indicate that snake venom phospholipase B-like enzymes are Ntn-hydrolases. Toxicon 2018; 153:106-113. [DOI: 10.1016/j.toxicon.2018.08.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/14/2018] [Accepted: 08/27/2018] [Indexed: 12/22/2022]
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10
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Vadakkan K, Choudhury AA, Gunasekaran R, Hemapriya J, Vijayanand S. Quorum sensing intervened bacterial signaling: Pursuit of its cognizance and repression. J Genet Eng Biotechnol 2018; 16:239-252. [PMID: 30733731 PMCID: PMC6353778 DOI: 10.1016/j.jgeb.2018.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 06/09/2018] [Accepted: 07/03/2018] [Indexed: 01/24/2023]
Abstract
Bacteria communicate within a system by means of a density dependent mechanism known as quorum sensing which regulate the metabolic and behavioral activities of a bacterial community. This sort of interaction occurs through a dialect of chemical signals called as autoinducers synthesized by bacteria. Bacterial quorum sensing occurs through various complex pathways depending upon specious diversity. Therefore the cognizance of quorum sensing mechanism will enable the regulation and thereby constrain bacterial communication. Inhibition strategies of quorum sensing are collectively called as quorum quenching; through which bacteria are incapacitated of its interaction with each other. Many virulence mechanism such as sporulation, biofilm formation, toxin production can be blocked by quorum quenching. Usually quorum quenching mechanisms can be broadly classified into enzymatic methods and non-enzymatic methods. Substantial understanding of bacterial communication and its inhibition enhances the development of novel antibacterial therapeutic drugs. In this review we have discussed the types and mechanisms of quorum sensing and various methods to inhibit and regulate density dependent bacterial communication.
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Affiliation(s)
- Kayeen Vadakkan
- Bioresource Technology Lab, Department of Biotechnology, Thiruvalluvar University, Vellore, TN 632115, India
| | - Abbas Alam Choudhury
- Bioresource Technology Lab, Department of Biotechnology, Thiruvalluvar University, Vellore, TN 632115, India
| | - Ramya Gunasekaran
- Bioresource Technology Lab, Department of Biotechnology, Thiruvalluvar University, Vellore, TN 632115, India
| | | | - Selvaraj Vijayanand
- Bioresource Technology Lab, Department of Biotechnology, Thiruvalluvar University, Vellore, TN 632115, India
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11
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Structural basis of the correct subunit assembly, aggregation, and intracellular degradation of nylon hydrolase. Sci Rep 2018; 8:9725. [PMID: 29950566 PMCID: PMC6021441 DOI: 10.1038/s41598-018-27860-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 06/12/2018] [Indexed: 11/09/2022] Open
Abstract
Nylon hydrolase (NylC) is initially expressed as an inactive precursor (36 kDa). The precursor is cleaved autocatalytically at Asn266/Thr267 to generate an active enzyme composed of an α subunit (27 kDa) and a β subunit (9 kDa). Four αβ heterodimers (molecules A-D) form a doughnut-shaped quaternary structure. In this study, the thermostability of the parental NylC was altered by amino acid substitutions located at the A/D interface (D122G/H130Y/D36A/L137A) or the A/B interface (E263Q) and spanned a range of 47 °C. Considering structural, biophysical, and biochemical analyses, we discuss the structural basis of the stability of nylon hydrolase. From the analytical centrifugation data obtained regarding the various mutant enzymes, we conclude that the assembly of the monomeric units is dynamically altered by the mutations. Finally, we propose a model that can predict whether the fate of the nascent polypeptide will be correct subunit assembly, inappropriate protein-protein interactions causing aggregation, or intracellular degradation of the polypeptide.
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12
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A Novel Quorum-Quenching N-Acylhomoserine Lactone Acylase from Acidovorax sp. Strain MR-S7 Mediates Antibiotic Resistance. Appl Environ Microbiol 2017; 83:AEM.00080-17. [PMID: 28455333 PMCID: PMC5478981 DOI: 10.1128/aem.00080-17] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 04/03/2017] [Indexed: 11/22/2022] Open
Abstract
N-Acylhomoserine lactone acylase (AHL acylase) is a well-known enzyme responsible for disrupting cell-cell communication (quorum sensing) in bacteria. Here, we isolated and characterized a novel and unique AHL acylase (designated MacQ) from a multidrug-resistant bacterium, Acidovorax sp. strain MR-S7. The purified MacQ protein heterologously expressed in Escherichia coli degraded a wide variety of AHLs, ranging from C6 to C14 side chains with or without 3-oxo substitutions. We also observed that AHL-mediated virulence factor production in a plant pathogen, Pectobacterium carotovorum, was dramatically attenuated by coculture with MacQ-overexpressing Escherichia coli, whereas E. coli with an empty vector was unable to quench the pathogenicity, which strongly indicates that MacQ can act in vivo as a quorum-quenching enzyme and interfere with the quorum-sensing system in the pathogen. In addition, this enzyme was found to be capable of degrading a wide spectrum of β-lactams (penicillin G, ampicillin, amoxicillin, carbenicillin, cephalexin, and cefadroxil) by deacylation, clearly indicating that MacQ is a bifunctional enzyme that confers both quorum quenching and antibiotic resistance on strain MR-S7. MacQ has relatively low amino acid sequence identity to any of the known acylases (<39%) and has among the broadest substrate range. Our findings provide the possibility that AHL acylase genes can be an alternative source of antibiotic resistance genes posing a threat to human health if they migrate and transfer to pathogenic bacteria. IMPORTANCEN-Acylhomoserine lactones (AHLs) are well-known signal molecules for bacterial cell-cell communication (quorum sensing), and AHL acylase, which is able to degrade AHLs, has been recognized as a major target for quorum-sensing interference (quorum quenching) in pathogens. In this work, we succeeded in isolating a novel AHL acylase (MacQ) from a multidrug-resistant bacterium and demonstrated that the MacQ enzyme could confer multidrug resistance as well as quorum quenching on the host organism. Indeed, the purified MacQ protein was found to be bifunctional and capable of degrading not only various AHL derivatives but also multiple β-lactam antibiotics by deacylation activities. Although quorum quenching and antibiotic resistance have been recognized to be distinct biological functions, our findings clearly link the two functions by discovering the novel bifunctional enzyme and further providing the possibility that a hitherto-overlooked antibiotic resistance mechanism mediated by the quorum-quenching enzyme may exist in natural environments and perhaps in clinical settings.
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Chand D, Avinash VS, Yadav Y, Pundle AV, Suresh CG, Ramasamy S. Molecular features of bile salt hydrolases and relevance in human health. Biochim Biophys Acta Gen Subj 2017; 1861:2981-2991. [DOI: 10.1016/j.bbagen.2016.09.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 09/20/2016] [Accepted: 09/23/2016] [Indexed: 01/18/2023]
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14
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Tian Y, Xu Z, Huang X, Zhu Y. Computational design to improve catalytic activity of cephalosporin C acylase from Pseudomonas strain N176. RSC Adv 2017. [DOI: 10.1039/c7ra04597b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Engineering enzymes with high catalytic activities using enzyme designin silicoand a limited number of experimental evaluations is the new trend for the discovery of highly efficient biocatalysts.
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Affiliation(s)
- Ye Tian
- Department of Chemical Engineering
- Tsinghua University
- Beijing 100084
- PR China
| | - Zhaobin Xu
- Department of Chemical Engineering
- Tsinghua University
- Beijing 100084
- PR China
| | - Xiaoqiang Huang
- Department of Chemical Engineering
- Tsinghua University
- Beijing 100084
- PR China
| | - Yushan Zhu
- Department of Chemical Engineering
- Tsinghua University
- Beijing 100084
- PR China
- MOE Key Lab of Industrial Biocatalysis
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15
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Computational design of variants for cephalosporin C acylase from Pseudomonas strain N176 with improved stability and activity. Appl Microbiol Biotechnol 2016; 101:621-632. [PMID: 27557716 DOI: 10.1007/s00253-016-7796-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/16/2016] [Accepted: 08/05/2016] [Indexed: 01/06/2023]
Abstract
In this report, redesigning cephalosporin C acylase from the Pseudomonas strain N176 revealed that the loss of stability owing to the introduced mutations at the active site can be recovered by repacking the nearby hydrophobic core regions. Starting from a quadruple mutant M31βF/H57βS/V68βA/H70βS, whose decrease in stability is largely owing to the mutation V68βA at the active site, we employed a computational enzyme design strategy that integrated design both at hydrophobic core regions for stability enhancement and at the active site for activity improvement. Single-point mutations L154βF, Y167βF, L180βF and their combinations L154βF/L180βF and L154βF/Y167βF/L180βF were found to display improved stability and activity. The two-point mutant L154βF/L180βF increased the protein melting temperature (T m) by 11.7 °C and the catalytic efficiency V max/K m by 57 % compared with the values of the starting quadruple mutant. The catalytic efficiency of the resulting sixfold mutant M31βF/H57βS/V68βA/H70βS/L154βF/L180βF is recovered to become comparable to that of the triple mutant M31βF/H57βS/H70βS, but with a higher T m. Further experiments showed that single-point mutations L154βF, L180βF, and their combination contribute no stability enhancement to the triple mutant M31βF/H57βS/H70βS. These results verify that the lost stability because of mutation V68βA at the active site was recovered by introducing mutations L154βF and L180βF at hydrophobic core regions. Importantly, mutation V68βA in the six-residue mutant provides more space to accommodate the bulky side chain of cephalosporin C, which could help in designing cephalosporin C acylase mutants with higher activities and the practical one-step enzymatic route to prepare 7-aminocephalosporanic acid at industrial-scale levels.
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16
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Huang X, Xue J, Lin M, Zhu Y. Use of an Improved Matching Algorithm to Select Scaffolds for Enzyme Design Based on a Complex Active Site Model. PLoS One 2016; 11:e0156559. [PMID: 27243223 PMCID: PMC4887040 DOI: 10.1371/journal.pone.0156559] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 05/16/2016] [Indexed: 11/24/2022] Open
Abstract
Active site preorganization helps native enzymes electrostatically stabilize the transition state better than the ground state for their primary substrates and achieve significant rate enhancement. In this report, we hypothesize that a complex active site model for active site preorganization modeling should help to create preorganized active site design and afford higher starting activities towards target reactions. Our matching algorithm ProdaMatch was improved by invoking effective pruning strategies and the native active sites for ten scaffolds in a benchmark test set were reproduced. The root-mean squared deviations between the matched transition states and those in the crystal structures were < 1.0 Å for the ten scaffolds, and the repacking calculation results showed that 91% of the hydrogen bonds within the active sites are recovered, indicating that the active sites can be preorganized based on the predicted positions of transition states. The application of the complex active site model for de novo enzyme design was evaluated by scaffold selection using a classic catalytic triad motif for the hydrolysis of p-nitrophenyl acetate. Eighty scaffolds were identified from a scaffold library with 1,491 proteins and four scaffolds were native esterase. Furthermore, enzyme design for complicated substrates was investigated for the hydrolysis of cephalexin using scaffold selection based on two different catalytic motifs. Only three scaffolds were identified from the scaffold library by virtue of the classic catalytic triad-based motif. In contrast, 40 scaffolds were identified using a more flexible, but still preorganized catalytic motif, where one scaffold corresponded to the α-amino acid ester hydrolase that catalyzes the hydrolysis and synthesis of cephalexin. Thus, the complex active site modeling approach for de novo enzyme design with the aid of the improved ProdaMatch program is a promising approach for the creation of active sites with high catalytic efficiencies towards target reactions.
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Affiliation(s)
- Xiaoqiang Huang
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, P.R. China
| | - Jing Xue
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, P.R. China
| | - Min Lin
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, P.R. China
| | - Yushan Zhu
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, P.R. China
- * E-mail:
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17
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Overexpression of penicillin V acylase from Streptomyces lavendulae and elucidation of its catalytic residues. Appl Environ Microbiol 2016; 81:1225-33. [PMID: 25501472 DOI: 10.1128/aem.02352-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The pva gene from Streptomyces lavendulae ATCC 13664, encoding a novel penicillin V acylase (SlPVA), has been isolated and characterized. The gene encodes an inactive precursor protein containing a secretion signal peptide that is activated by two internal autoproteolytic cleavages that release a 25-amino-acid linker peptide and two large domains of 18.79 kDa (alpha-subunit) and 60.09 kDA (beta-subunit). Based on sequence alignments and the three-dimensional model of SlPVA, the enzyme contains a hydrophobicpocket involved in catalytic activity, including Serbeta1, Hisbeta23, Valbeta70, and Asnbeta272, which were confirmed by site-directed mutagenesis studies. The heterologous expression of pva in S. lividans led to the production of an extracellularly homogeneous heterodimeric enzyme at a 5-fold higher concentration (959 IU/liter) than in the original host and in a considerably shorter time. According to the catalytic properties of SlPVA, the enzyme must be classified as a new member of the Ntn-hydrolase superfamily, which belongs to a novel subfamily of acylases that recognize substrates with long hydrophobic acyl chains and have biotechnological applications in semisynthetic antifungal production.
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18
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Pica A, Chi MC, Chen YY, d'Ischia M, Lin LL, Merlino A. The maturation mechanism of γ-glutamyl transpeptidases: Insights from the crystal structure of a precursor mimic of the enzyme from Bacillus licheniformis and from site-directed mutagenesis studies. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1864:195-203. [PMID: 26536828 DOI: 10.1016/j.bbapap.2015.10.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 10/26/2015] [Accepted: 10/28/2015] [Indexed: 01/20/2023]
Abstract
γ-Glutamyl transpeptidases (γ-GTs) are members of N-terminal nucleophile hydrolase superfamily. They are synthetized as single-chain precursors, which are then cleaved to form mature enzymes. Basic aspects of autocatalytic processing of these pro-enzymes are still unknown. Here we describe the X-ray structure of the precursor mimic of Bacillus licheniformis γ-GT (BlGT), obtained by mutating catalytically important threonine to alanine (T399A-BlGT), and report results of autoprocessing of mutants of His401, Thr415, Thr417, Glu419 and Arg571. Data suggest that Thr417 is in a competent position to activate the catalytic threonine (Thr399) for nucleophilic attack of the scissile peptide bond and that Thr415 plays a major role in assisting the process. On the basis of these new structural results, a possible mechanism of autoprocessing is proposed. This mechanism, which guesses the existence of a six-membered transition state involving one carbonyl and two hydroxyl groups, is in agreement with all the available experimental data collected on γ-GTs from different species and with our new Ala-scanning mutagenesis data.
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Affiliation(s)
- Andrea Pica
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia, Naples I-80126, Italy; Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone, 16, Naples 80133, Italy
| | - Meng-Chun Chi
- Department of Applied Chemistry, National Chiayi University, 300 Syuefu Road, Chiayi City 60004, Taiwan
| | - Yi-Yu Chen
- Department of Applied Chemistry, National Chiayi University, 300 Syuefu Road, Chiayi City 60004, Taiwan
| | - Marco d'Ischia
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia, Naples I-80126, Italy
| | - Long-Liu Lin
- Department of Applied Chemistry, National Chiayi University, 300 Syuefu Road, Chiayi City 60004, Taiwan
| | - Antonello Merlino
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia, Naples I-80126, Italy; Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone, 16, Naples 80133, Italy.
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19
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Cephalosporin C acylase from Pseudomonas species: Production and enhancement of its activity by optimization of process parameters. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2015. [DOI: 10.1016/j.bcab.2015.06.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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20
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An effective method for extraction of glutaryl-7-aminocephalosporanic acid acylase from recombinant E. coli cells. BIOTECHNOL BIOPROC E 2015. [DOI: 10.1007/s12257-013-0607-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Balakrishna S, Prabhune AA. Gamma-glutamyl transferases: A structural, mechanistic and physiological perspective. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s11515-014-1288-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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22
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Terwagne M, Mirabella A, Lemaire J, Deschamps C, De Bolle X, Letesson JJ. Quorum sensing and self-quorum quenching in the intracellular pathogen Brucellamelitensis. PLoS One 2013; 8:e82514. [PMID: 24349302 PMCID: PMC3859601 DOI: 10.1371/journal.pone.0082514] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 10/24/2013] [Indexed: 11/19/2022] Open
Abstract
Brucella quorum sensing has been described as an important regulatory system controlling crucial virulence determinants such as the VirB type IV secretion system and the flagellar genes. However, the basis of quorum sensing, namely the production of autoinducers in Brucella has been questioned. Here, we report data obtained from the use of a genetic tool allowing the in situ detection of long-chain N-acyl-homoserine lactones (AHL) activity at single bacterium level in Brucella melitensis. These data are consistent with an intrinsic production of AHL by B. melitensis in low concentration both during in vitro growth and macrophage infection. Moreover, we identified a protein, named AibP, which is homologous to the AHL-acylases of various bacterial species. In vitro and during infection, expression of aibP coincided with a decrease in endogenous AHL activity within B. melitensis, suggesting that AibP could efficiently impair AHL accumulation. Furthermore, we showed that deletion of aibP in B. melitensis resulted in enhanced virB genes expression and VirB8 production as well as in a reduced flagellar genes expression and production of FlgE (hook protein) and FliC (flagellin) in vitro. Altogether, these results suggest that AHL-dependent quorum sensing and AHL-quorum quenching coexist in Brucella, at least to regulate its virulence.
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Affiliation(s)
| | | | - Julien Lemaire
- URBM, Department of Biology, University of Namur, Namur, Belgium
| | | | - Xavier De Bolle
- URBM, Department of Biology, University of Namur, Namur, Belgium
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23
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Zakirova SA, Mikhailova TV, Eldarov MA. Peculiarities of the Brevundimonas diminuta Gl7ACA-acylase quaternary structure formation and obtaining stable enzyme analogues. APPL BIOCHEM MICRO+ 2013. [DOI: 10.1134/s0003683813060185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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High-level expression of glutaryl-7-aminocephalosporanic acid acylase from Pseudomonas diminuta NK703 in Escherichia coli by combined optimization strategies. J Biotechnol 2013; 168:607-15. [PMID: 23994688 DOI: 10.1016/j.jbiotec.2013.08.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 08/15/2013] [Accepted: 08/17/2013] [Indexed: 11/23/2022]
Abstract
In this work, a glutaryl-7-aminocephalosporanic acid acylase (GLA) coding gene was cloned from Pseudomonas diminuta NK703 which was screened from oilfield. The concerted effects of the expression system, inducing condition and culture medium on the expression of NK703 GLA in E. coli were firstly investigated. The best combination was the recombinant E. coli strain of pET-28a+GLA/BL21(DE3) with 2.0% (w/v) lactose inducing in YT medium at 25°C. Then, by optimizing the components of culture medium, a synthetic medium with dextrin and a feeding medium with glycerol as the carbon sources were developed to further enhance the GLA yield and improve the GLA solubility. In the end, the NK703 GLA activity increased about 50-fold, reached 14,470 ± 465 U/L, and the GLA productivity and the proportion of soluble GLA to the total soluble protein attained 206.0 ± 9.033 UL(-1)h(-1) and 60.13%, respectively. Scaling up the GLA production in 3.7 L fermenter under the optimized conditions identified in shake flask, the GLA activity also reached 12,406±521U/L, which was the highest report at fermenter level.
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25
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Structure of a class III engineered cephalosporin acylase: comparisons with class I acylase and implications for differences in substrate specificity and catalytic activity. Biochem J 2013; 451:217-26. [DOI: 10.1042/bj20121715] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The crystal structure of the wild-type form of glutaryl-7-ACA (7-aminocephalosporanic acid) acylase from Pseudomonas N176 and a double mutant of the protein (H57βS/H70βS) that displays enhanced catalytic efficiency on cephalosporin C over glutaryl-7-aminocephalosporanic acid has been determined. The structures show a heterodimer made up of an α-chain (229 residues) and a β-chain (543 residues) with a deep cavity, which constitutes the active site. Comparison of the wild-type and mutant structures provides insights into the molecular reasons for the observed enhanced specificity on cephalosporin C over glutaryl-7-aminocephalosporanic acid and offers the basis to evolve a further improved enzyme variant. The nucleophilic catalytic serine residue, Ser1β, is situated at the base of the active site cavity. The electron density reveals a ligand covalently bound to the catalytic serine residue, such that a tetrahedral adduct is formed. This is proposed to mimic the transition state of the enzyme for both the maturation step and the catalysis of the substrates. A view of the transition state configuration of the enzyme provides important insights into the mechanism of substrate binding and catalysis.
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26
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Pollegioni L, Rosini E, Molla G. Cephalosporin C acylase: dream and(/or) reality. Appl Microbiol Biotechnol 2013; 97:2341-55. [PMID: 23417342 DOI: 10.1007/s00253-013-4741-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 01/24/2013] [Accepted: 01/24/2013] [Indexed: 11/30/2022]
Abstract
Cephalosporins currently constitute the most widely prescribed class of antibiotics and are used to treat diseases caused by both Gram-positive and Gram-negative bacteria. Cephalosporins contain a 7-aminocephalosporanic acid (7-ACA) nucleus which is derived from cephalosporin C (CephC). The 7-ACA nucleus is not sufficiently potent for clinical use; however, a series of highly effective antibiotic agents could be produced by modifying the side chains linked to the 7-ACA nucleus. The industrial production of higher-generation semi-synthetic cephalosporins starts from 7-ACA, which is obtained by deacylation of the naturally occurring antibiotic CephC. CephC can be converted to 7-ACA either chemically or enzymatically using D-amino acid oxidase and glutaryl-7-aminocephalosporanic acid acylase. Both these methods show limitation, including the production of toxic waste products (chemical process) and the expense (the enzymatic one). In order to circumvent these problems, attempts have been undertaken to design a single-step means of enzymatically converting CephC to 7-ACA in the course of the past 10 years. The most suitable approach is represented by engineering the activity of a known glutaryl-7-aminocephalosporanic acid acylase such that it will bind and deacylate CephC more preferentially over glutaryl-7-aminocephalosporanic acid. Here, we describe the state of the art in the production of an effective and specific CephC acylase.
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Affiliation(s)
- Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, Varese, Italy.
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27
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Hamed RB, Gomez-Castellanos JR, Henry L, Ducho C, McDonough MA, Schofield CJ. The enzymes of β-lactam biosynthesis. Nat Prod Rep 2013; 30:21-107. [DOI: 10.1039/c2np20065a] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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28
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Negoro S, Shibata N, Tanaka Y, Yasuhira K, Shibata H, Hashimoto H, Lee YH, Oshima S, Santa R, Oshima S, Mochiji K, Goto Y, Ikegami T, Nagai K, Kato DI, Takeo M, Higuchi Y. Three-dimensional structure of nylon hydrolase and mechanism of nylon-6 hydrolysis. J Biol Chem 2011; 287:5079-90. [PMID: 22187439 DOI: 10.1074/jbc.m111.321992] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We performed x-ray crystallographic analyses of the 6-aminohexanoate oligomer hydrolase (NylC) from Agromyces sp. at 2.0 Å-resolution. This enzyme is a member of the N-terminal nucleophile hydrolase superfamily that is responsible for the degradation of the nylon-6 industry byproduct. We observed four identical heterodimers (27 kDa + 9 kDa), which resulted from the autoprocessing of the precursor protein (36 kDa) and which constitute the doughnut-shaped quaternary structure. The catalytic residue of NylC was identified as the N-terminal Thr-267 of the 9-kDa subunit. Furthermore, each heterodimer is folded into a single domain, generating a stacked αββα core structure. Amino acid mutations at subunit interfaces of the tetramer were observed to drastically alter the thermostability of the protein. In particular, four mutations (D122G/H130Y/D36A/E263Q) of wild-type NylC from Arthrobacter sp. (plasmid pOAD2-encoding enzyme), with a heat denaturation temperature of T(m) = 52 °C, enhanced the protein thermostability by 36 °C (T(m) = 88 °C), whereas a single mutation (G111S or L137A) decreased the stability by ∼10 °C. We examined the enzymatic hydrolysis of nylon-6 by the thermostable NylC mutant. Argon cluster secondary ion mass spectrometry analyses of the reaction products revealed that the major peak of nylon-6 (m/z 10,000-25,000) shifted to a smaller range, producing a new peak corresponding to m/z 1500-3000 after the enzyme treatment at 60 °C. In addition, smaller fragments in the soluble fraction were successively hydrolyzed to dimers and monomers. Based on these data, we propose that NylC should be designated as nylon hydrolase (or nylonase). Three potential uses of NylC for industrial and environmental applications are also discussed.
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Affiliation(s)
- Seiji Negoro
- Department of Materials Science and Chemistry, Graduate School of Engineering, University of Hyogo, Hyogo 671-2280
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29
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Yin J, Deng Z, Zhao G, Huang X. The N-terminal nucleophile serine of cephalosporin acylase executes the second autoproteolytic cleavage and acylpeptide hydrolysis. J Biol Chem 2011; 286:24476-86. [PMID: 21576250 DOI: 10.1074/jbc.m111.242313] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cephalosporin acylase (CA) precursor is translated as a single polypeptide chain and folds into a self-activating pre-protein. Activation requires two peptide bond cleavages that excise an internal spacer to form the mature αβ heterodimer. Using Q-TOF LC-MS, we located the second cleavage site between Glu(159) and Gly(160), and detected the corresponding 10-aa spacer (160)GDPPDLADQG(169) of CA mutants. The site of the second cleavage depended on Glu(159): moving Glu into the spacer or removing 5-10 residues from the spacer sequence resulted in shorter spacers with the cleavage at the carboxylic side of Glu. The mutant E159D was cleaved more slowly than the wild-type, as were mutants G160A and G160L. This allowed kinetic measurements showing that the second cleavage reaction was a first-order, intra-molecular process. Glutaryl-7-aminocephalosporanic acid is the classic substrate of CA, in which the N-terminal Ser(170) of the β-subunit, is the nucleophile. Glu and Asp resemble glutaryl, suggesting that CA might also remove N-terminal Glu or Asp from peptides. This was indeed the case, suggesting that the N-terminal nucleophile also performed the second proteolytic cleavage. We also found that CA is an acylpeptide hydrolase rather than a previously expected acylamino acid acylase. It only exhibited exopeptidase activity for the hydrolysis of an externally added peptide, supporting the intra-molecular interaction. We propose that the final CA activation is an intra-molecular process performed by an N-terminal nucleophile, during which large conformational changes in the α-subunit C-terminal region are required to bridge the gap between Glu(159) and Ser(170).
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Affiliation(s)
- Jun Yin
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China
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30
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Amara N, Krom BP, Kaufmann GF, Meijler MM. Macromolecular inhibition of quorum sensing: enzymes, antibodies, and beyond. Chem Rev 2010; 111:195-208. [PMID: 21087050 DOI: 10.1021/cr100101c] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Neri Amara
- Department of Chemistry and National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Be'er Sheva, Israel
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31
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Suzuki H, Yamada C, Kijima K, Ishihara S, Wada K, Fukuyama K, Kumagai H. Enhancement of glutaryl-7-aminocephalosporanic acid acylase activity of γ-glutamyltranspeptidase of Bacillus subtilis. Biotechnol J 2010; 5:829-37. [DOI: 10.1002/biot.201000015] [Citation(s) in RCA: 9] [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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32
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Bokhove M, Yoshida H, Hensgens CMH, van der Laan JM, Sutherland JD, Dijkstra BW. Structures of an isopenicillin N converting Ntn-hydrolase reveal different catalytic roles for the active site residues of precursor and mature enzyme. Structure 2010; 18:301-8. [PMID: 20223213 DOI: 10.1016/j.str.2010.01.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 01/06/2010] [Accepted: 01/18/2010] [Indexed: 10/19/2022]
Abstract
Penicillium chrysogenum Acyl coenzyme A:isopenicillin N acyltransferase (AT) performs the last step in the biosynthesis of hydrophobic penicillins, exchanging the hydrophilic side chain of a precursor for various hydrophobic side chains. Like other N-terminal nucleophile hydrolases AT is produced as an inactive precursor that matures upon posttranslational cleavage. The structure of a Cys103Ala precursor mutant shows that maturation is autoproteolytic, initiated by Cys103 cleaving its preceding peptide bond. The crystal structure of the mature enzyme shows that after autoproteolysis residues 92-102 fold outwards, exposing a buried pocket. This pocket is structurally and chemically flexible and can accommodate substrates of different size and polarity. Modeling of a substrate-bound state indicates the residues important for catalysis. Comparison of the proposed autoproteolytic and substrate hydrolysis mechanisms shows that in both events the same catalytic residues are used, but that they perform different roles in catalysis.
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Affiliation(s)
- Marcel Bokhove
- Laboratory of Biophysical Chemistry, University of Groningen, Nijenborgh 4, Groningen, Netherlands
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33
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Anandan A, Vallet C, Coyle T, Moustafa IM, Vrielink A. Crystallization and preliminary diffraction analysis of an engineered cephalosporin acylase. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:808-10. [PMID: 20606279 PMCID: PMC2898467 DOI: 10.1107/s1744309110017185] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Accepted: 05/11/2010] [Indexed: 05/03/2024]
Abstract
Crystallization conditions are reported for an engineered cephalosporin acylase based on the sequence of glutaryl-7-aminocephalosporanic acid acylase from Pseudomonas strain N176. Initial crystals were grown using polyethylene glycol as a crystallizing agent; however, these crystals diffracted poorly and exhibited high mosaicity. A dehydration procedure in which crystals were transferred to a solution containing a higher concentration of polyethylene glycol as well as glycerol improved the diffraction quality such that a 1.57 A diffraction data set could be obtained.
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Affiliation(s)
- Anandhi Anandan
- School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Corinne Vallet
- School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Travis Coyle
- School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Ibrahim M. Moustafa
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, 201 Althouse Laboratory, University Park, PA 16802, USA
| | - Alice Vrielink
- School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
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34
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Boniello C, Mayr T, Klimant I, Koenig B, Riethorst W, Nidetzky B. Intraparticle concentration gradients for substrate and acidic product in immobilized cephalosporin C amidase and their dependencies on carrier characteristics and reaction parameters. Biotechnol Bioeng 2010; 106:528-40. [DOI: 10.1002/bit.22694] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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The quorum-quenching N-acyl homoserine lactone acylase PvdQ is an Ntn-hydrolase with an unusual substrate-binding pocket. Proc Natl Acad Sci U S A 2009; 107:686-91. [PMID: 20080736 DOI: 10.1073/pnas.0911839107] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In many Gram-negative pathogens, their virulent behavior is regulated by quorum sensing, in which diffusible signals such as N-acyl homoserine lactones (AHLs) act as chemical messaging compounds. Enzymatic degradation of these diffusible signals by, e.g., lactonases or amidohydrolases abolishes AHL regulated virulence, a process known as quorum quenching. Here we report the first crystal structure of an AHL amidohydrolase, the AHL acylase PvdQ from Pseudomonas aeruginosa. PvdQ has a typical alpha/beta heterodimeric Ntn-hydrolase fold, similar to penicillin G acylase and cephalosporin acylase. However, it has a distinct, unusually large, hydrophobic binding pocket, ideally suited to recognize C12 fatty acid-like chains of AHLs. Binding of a C12 fatty acid or a 3-oxo-C12 fatty acid induces subtle conformational changes to accommodate the aliphatic chain. Furthermore, the structure of a covalent ester intermediate identifies Serbeta1 as the nucleophile and Asnbeta269 and Valbeta70 as the oxyanion hole residues in the AHL degradation process. Our structures show the versatility of the Ntn-hydrolase scaffold and can serve as a structural paradigm for Ntn-hydrolases with similar substrate preference. Finally, the quorum-quenching capabilities of PvdQ may be utilized to suppress the quorum-sensing machinery of pathogens.
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36
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Cho KJ, Kim JK, Lee JH, Shin HJ, Park SS, Kim KH. Structural features of cephalosporin acylase reveal the basis of autocatalytic activation. Biochem Biophys Res Commun 2009; 390:342-8. [PMID: 19800869 DOI: 10.1016/j.bbrc.2009.09.134] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 09/30/2009] [Indexed: 10/20/2022]
Abstract
Cephalosporin acylase (CA), a member of the N-terminal nucleophile hydrolase family, is activated through two steps of intramolecular autoproteolysis, the first mediated by a serine residue, and the second by a glutamate, which releases the pro-segment and produces an active enzyme. In this study, we have determined the crystal structures of mutants which could affect primary or secondary auto-cleavage and of sequential intermediates of a slow-processing mutant at 2.0-2.5A resolutions. The pro-segments of the mutants undergo dynamic conformational changes during activation and adopt surprisingly different loop conformations from one another. However, the autoproteolytic site was found to form a catalytically competent conformation with a solvent water molecule, which was essentially conserved in the CA mutants.
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Affiliation(s)
- Ki Joon Cho
- Department of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Republic of Korea
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37
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Lakomek K, Dickmanns A, Kettwig M, Urlaub H, Ficner R, Lübke T. Initial insight into the function of the lysosomal 66.3 kDa protein from mouse by means of X-ray crystallography. BMC STRUCTURAL BIOLOGY 2009; 9:56. [PMID: 19706171 PMCID: PMC2739207 DOI: 10.1186/1472-6807-9-56] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 08/25/2009] [Indexed: 08/30/2023]
Abstract
Background The lysosomal 66.3 kDa protein from mouse is a soluble, mannose 6-phosphate containing protein of so far unknown function. It is synthesized as a glycosylated 75 kDa precursor that undergoes limited proteolysis leading to a 28 kDa N- and a 40 kDa C-terminal fragment. Results In order to gain insight into the function and the post-translational maturation process of the glycosylated 66.3 kDa protein, three crystal structures were determined that represent different maturation states. These structures demonstrate that the 28 kDa and 40 kDa fragment which have been derived by a proteolytic cleavage remain associated. Mass spectrometric analysis confirmed the subsequent trimming of the C-terminus of the 28 kDa fragment making a large pocket accessible, at the bottom of which the putative active site is located. The crystal structures reveal a significant similarity of the 66.3 kDa protein to several bacterial hydrolases. The core αββα sandwich fold and a cysteine residue at the N-terminus of the 40 kDa fragment (C249) classify the 66.3 kDa protein as a member of the structurally defined N-terminal nucleophile (Ntn) hydrolase superfamily. Conclusion Due to the close resemblance of the 66.3 kDa protein to members of the Ntn hydrolase superfamily a hydrolytic activity on substrates containing a non-peptide amide bond seems reasonable. The structural homology which comprises both the overall fold and essential active site residues also implies an autocatalytic maturation process of the lysosomal 66.3 kDa protein. Upon the proteolytic cleavage between S248 and C249, a deep pocket becomes solvent accessible, which harbors the putative active site of the 66.3 kDa protein.
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Affiliation(s)
- Kristina Lakomek
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, GZMB, Georg-August University Goettingen, Justus-von-Liebig-Weg 11, D-37077 Goettingen, Germany.
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Sonawane VC. Enzymatic Modifications of Cephalosporins by Cephalosporin Acylase and Other Enzymes. Crit Rev Biotechnol 2008; 26:95-120. [PMID: 16809100 DOI: 10.1080/07388550600718630] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Semisynthetic cephalosporins are important antibacterials in clinical practice. Semisynthetic cephalosporins are manufactured by derivatizing 7-aminocephalosporanic acid (7-ACA) and its desacetylated form. Microbial enzymes such as D-amino acid oxidase, glutaryl-7-ACA acylase and cephalosporin esterase are being used as biocatalysts for the conversion of cephalosporin C (CEPH-C) to 7-ACA and its desacetylated derivatives. Recent developments in the field of enzymatic modifications of cephalosporin with special emphasis on group of enzymes called as cephalosporin acylase is discussed in this review. Aspects related to screening methods, isolation and purification, immobilization, molecular cloning, gene structure and expression and protein engineering of cephalosporin acylases have been covered. Topics pertaining to enzymatic modifications of cephalosporin by D-amino acid oxidase, cephalosporin methoxylase and beta-lactamase are also covered.
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Michalska K, Hernandez-Santoyo A, Jaskolski M. The Mechanism of Autocatalytic Activation of Plant-type L-Asparaginases. J Biol Chem 2008; 283:13388-97. [DOI: 10.1074/jbc.m800746200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Otten LG, Sio CF, Reis CR, Koch G, Cool RH, Quax WJ. A highly active adipyl-cephalosporin acylase obtained via rational randomization. FEBS J 2007; 274:5600-10. [DOI: 10.1111/j.1742-4658.2007.06081.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Dong YH, Wang LH, Zhang LH. Quorum-quenching microbial infections: mechanisms and implications. Philos Trans R Soc Lond B Biol Sci 2007; 362:1201-11. [PMID: 17360274 PMCID: PMC2435583 DOI: 10.1098/rstb.2007.2045] [Citation(s) in RCA: 255] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The discovery of antibiotics early in the past century marked the beginning of active control and prevention of infectious microbial diseases. However, extensive use of antibiotics has also unavoidably resulted in the emergence of ‘superbugs’ that resist conventional antibiotics. The finding that many pathogens rely on cell-to-cell communication mechanisms, known as quorum sensing, to synchronize microbial activities essential for infection and survival in the host suggests a promising disease control strategy, i.e. quenching microbial quorum sensing or in short, quorum quenching. Work over the past few years has demonstrated that quorum-quenching mechanisms are widely conserved in many prokaryotic and eukaryotic organisms. These naturally occurring quorum-quenching mechanisms appear to play important roles in microbe–microbe and pathogen–host interactions and have been used, or served as lead compounds, in developing and formulating a new generation of antimicrobials. Characterization of the crystal structures of several types of quorum-quenching enzymes has provided valuable information to elucidate the catalytic mechanisms, as well as clues for future protein tailoring and molecular improvement. The discovery of quorum-sensing signal degradation enzymes in mammalian species represents a new milestone in quorum sensing and quorum quenching research. The finding highlights the importance of investigating their roles in host innate defence against infectious diseases and to determine the factors influencing their
in vivo
concentrations and catalytic activities.
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Affiliation(s)
- Yi-Hu Dong
- Institute of Molecular and Cell Biology61 Biopolis Drive, Singapore 138673, Republic of Singapore
| | - Lian-Hui Wang
- Institute of Molecular and Cell Biology61 Biopolis Drive, Singapore 138673, Republic of Singapore
| | - Lian-Hui Zhang
- Institute of Molecular and Cell Biology61 Biopolis Drive, Singapore 138673, Republic of Singapore
- Department of Biological Sciences, The National University of Singapore10 Kent Ridge Crescent, Singapore 119260, Republic of Singapore
- Author for correspondence ()
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Zhang D, Koreishi M, Imanaka H, Imamura K, Nakanishi K. Cloning and characterization of penicillin V acylase from Streptomyces mobaraensis. J Biotechnol 2007; 128:788-800. [PMID: 17289203 DOI: 10.1016/j.jbiotec.2006.12.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Revised: 12/14/2006] [Accepted: 12/22/2006] [Indexed: 11/24/2022]
Abstract
We report on the molecular cloning and characterization of penicillin V acylase (PVA) from an actinomycete, Streptomyces mobaraensis (Sm-PVA), which was originally isolated as an acylase that efficiently hydrolyzes the amide bond of various N-fatty-acyl-l-amino acids and N-fatty-acyl-peptides as well as capsaicin (8-methyl-N-vanillyl-6-nonenamide). In addition, the purified Sm-PVA hydrolyzed penicillin V with the highest activity (k(cat)) among the PVAs so far reported, penicillin G, and 2-nitro-5-phenoxyacetamide benzoic acid. The BLAST search revealed that the Sm-PVA precursor is composed of a polypeptide that is characteristic of enzymes belonging to the beta-lactam acylase family with four distinct segments; a signal sequence (43 amino acids), an alpha subunit (173 amino acids), a linker peptide (28 amino acids), and a beta subunit (570 amino acids). The mature, active Sm-PVA is a heterodimeric protein with alpha and beta subunits, in contrast to PVAs isolated from Bacillus sphaericus and B. subtilis, which have a homotetrameric structure. The amino acid sequence of Sm-PVA showed identities to PVA from S. lavendulae, N-acylhomoserine lactone-degrading acylase from Streptomyces sp., cyclic lipopeptide acylase from Streptomyces sp., and aculeacin A acylase from Actinoplanes utahensis with 68, 67, 67, and 41% identities, respectively.
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Affiliation(s)
- Demin Zhang
- Department of Bioscience and Biotechnology, Faculty of Engineering, Okayama University, 3-1-1, Tsushima-Naka, Okayama 700-8530, Japan
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Wang Y, Guo HC. Crystallographic snapshot of a productive glycosylasparaginase-substrate complex. J Mol Biol 2006; 366:82-92. [PMID: 17157318 PMCID: PMC1865511 DOI: 10.1016/j.jmb.2006.09.051] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Revised: 09/02/2006] [Accepted: 09/20/2006] [Indexed: 11/18/2022]
Abstract
Glycosylasparaginase (GA) plays an important role in asparagine-linked glycoprotein degradation. A deficiency in the activity of human GA leads to a lysosomal storage disease named aspartylglycosaminuria. GA belongs to a superfamily of N-terminal nucleophile hydrolases that autoproteolytically generate their mature enzymes from inactive single chain protein precursors. The side-chain of the newly exposed N-terminal residue then acts as a nucleophile during substrate hydrolysis. By taking advantage of mutant enzyme of Flavobacterium meningosepticum GA with reduced enzymatic activity, we have obtained a crystallographic snapshot of a productive complex with its substrate (NAcGlc-Asn), at 2.0 A resolution. This complex structure provided us an excellent model for the Michaelis complex to examine the specific contacts critical for substrate binding and catalysis. Substrate binding induces a conformational change near the active site of GA. To initiate catalysis, the side-chain of the N-terminal Thr152 is polarized by the free alpha-amino group on the same residue, mediated by the side-chain hydroxyl group of Thr170. Cleavage of the amide bond is then accomplished by a nucleophilic attack at the carbonyl carbon of the amide linkage in the substrate, leading to the formation of an acyl-enzyme intermediate through a negatively charged tetrahedral transition state.
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Affiliation(s)
| | - Hwai-Chen Guo
- *Corresponding author: Hwai-Chen Guo, Department of Physiology and Biophysics, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118-2526, telephone: 617-638-4023, fax: 617-638-4041, E-mail:
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Sio CF, Otten LG, Cool RH, Diggle SP, Braun PG, Bos R, Daykin M, Cámara M, Williams P, Quax WJ. Quorum quenching by an N-acyl-homoserine lactone acylase from Pseudomonas aeruginosa PAO1. Infect Immun 2006; 74:1673-82. [PMID: 16495538 PMCID: PMC1418629 DOI: 10.1128/iai.74.3.1673-1682.2006] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The virulence of the opportunistic human pathogen Pseudomonas aeruginosa PAO1 is controlled by an N-acyl-homoserine lactone (AHL)-dependent quorum-sensing system. During functional analysis of putative acylase genes in the P. aeruginosa PAO1 genome, the PA2385 gene was found to encode an acylase that removes the fatty acid side chain from the homoserine lactone (HSL) nucleus of AHL-dependent quorum-sensing signal molecules. Analysis showed that the posttranslational processing of the acylase and the hydrolysis reaction type are similar to those of the beta-lactam acylases, strongly suggesting that the PA2385 protein is a member of the N-terminal nucleophile hydrolase superfamily. In a bioassay, the purified acylase was shown to degrade AHLs with side chains ranging in length from 11 to 14 carbons at physiologically relevant low concentrations. The substituent at the 3' position of the side chain did not affect activity, indicating broad-range AHL quorum-quenching activity. Of the two main AHL signal molecules of P. aeruginosa PAO1, N-butanoyl-l-homoserine lactone (C4-HSL) and N-(3-oxododecanoyl)-l-homoserine lactone (3-oxo-C12-HSL), only 3-oxo-C12-HSL is degraded by the enzyme. Addition of the purified protein to P. aeruginosa PAO1 cultures completely inhibited accumulation of 3-oxo-C12-HSL and production of the signal molecule 2-heptyl-3-hydroxy-4(1H)-quinolone and reduced production of the virulence factors elastase and pyocyanin. Similar results were obtained when the PA2385 gene was overexpressed in P. aeruginosa. These results demonstrate that the protein has in situ quorum-quenching activity. The quorum-quenching AHL acylase may enable P. aeruginosa PAO1 to modulate its own quorum-sensing-dependent pathogenic potential and, moreover, offers possibilities for novel antipseudomonal therapies.
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Affiliation(s)
- Charles F Sio
- Pharmaceutical Biology, University Centre for Pharmacy, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
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Kim JK, Yang IS, Shin HJ, Cho KJ, Ryu EK, Kim SH, Park SS, Kim KH. Insight into autoproteolytic activation from the structure of cephalosporin acylase: a protein with two proteolytic chemistries. Proc Natl Acad Sci U S A 2006; 103:1732-7. [PMID: 16446446 PMCID: PMC1413634 DOI: 10.1073/pnas.0507862103] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Indexed: 11/18/2022] Open
Abstract
Cephalosporin acylase (CA), a member of the N-terminal nucleophile hydrolase family, is activated through sequential primary and secondary autoproteolytic reactions with the release of a pro segment. We have determined crystal structures of four CA mutants. Two mutants are trapped after the primary cleavage, and the other two undergo secondary cleavage slowly. These structures provide a look at pro-segment conformation during activation in N-terminal nucleophile hydrolases. The highly strained helical pro segment of precursor is transformed into a relaxed loop in the intermediates, suggesting that the relaxation of structural constraints drives the primary cleavage reaction. The secondary autoproteolytic step has been proposed to be intermolecular. However, our analysis provides evidence that CA is processed in two sequential steps of intramolecular autoproteolysis involving two distinct residues in the active site, the first a serine and the second a glutamate.
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Affiliation(s)
- Jin Kwang Kim
- *Department of Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, and
| | - In Seok Yang
- *Department of Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, and
| | - Hye Jeong Shin
- Department of Bio-Microsystem Technology, Korea University, Seoul 136-701, Korea; and
| | - Ki Joon Cho
- *Department of Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, and
| | - Eui Kyung Ryu
- *Department of Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, and
| | - Sun Hwa Kim
- *Department of Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, and
| | - Sung Soo Park
- *Department of Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, and
| | - Kyung Hyun Kim
- Department of Bio-Microsystem Technology, Korea University, Seoul 136-701, Korea; and
- Department of Biotechnology, College of Science and Technology, Korea University, Jochiwon 339-700, Korea
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Jeong YS, Yoo HJ, Kim SD, Nam DH, Khang YH. Cloning and sequencing of a novel glutaryl acylase β-subunit gene ofPseudomonas cepacia BY21 from bioinformatics. BIOTECHNOL BIOPROC E 2005. [DOI: 10.1007/bf02932286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Zhang W, Liu Y, Zheng H, Yang S, Jiang W. Improving the activity and stability of GL-7-ACA acylase CA130 by site-directed mutagenesis. Appl Environ Microbiol 2005; 71:5290-6. [PMID: 16151116 PMCID: PMC1214626 DOI: 10.1128/aem.71.9.5290-5296.2005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In the present study, glutaryl-7-amino cephalosporanic acid acylase from Pseudomonas sp. strain 130 (CA130) was mutated to improve its enzymatic activity and stability. Based on the crystal structure of CA130, two series of amino acid residues, one from those directly involved in catalytic function and another from those putatively involved in surface charge, were selected as targets for site-directed mutagenesis. In the first series of experiments, several key residues in the substrate-binding pocket were substituted, and the genes were expressed in Escherichia coli for activity screening. Two of the mutants constructed, Y151alphaF and Q50betaN, showed two- to threefold-increased catalytic efficiency (k(cat)/K(m)) compared to wild-type CA130. Their K(m) values were decreased by ca. 50%, and the k(cat) values increased to 14.4 and 16.9 s(-1), respectively. The ability of these mutants to hydrolyze adipoyl 6-amino penicillinic acid was also improved. In the second series of mutagenesis, several mutants with enhanced stabilities were identified. Among them, R121betaA and K198betaA had a 30 to 58% longer half-life than wild-type CA130, and K198betaA and D286betaA showed an alkaline shift of optimal pH by about 1.0 to 2.0 pH units. To construct an engineered enzyme with the properties of both increased activity and stability, the double mutant Q50betaN/K198betaA was expressed. This enzyme was purified and immobilized for catalytic analysis. The immobilized mutant enzyme showed a 34.2% increase in specific activity compared to the immobilized wild-type CA130.
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Affiliation(s)
- Wei Zhang
- Laboratory of Molecular Microbiology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Rd., Shanghai 200032, People's Republic of China
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Pollegioni L, Lorenzi S, Rosini E, Marcone GL, Molla G, Verga R, Cabri W, Pilone MS. Evolution of an acylase active on cephalosporin C. Protein Sci 2005; 14:3064-76. [PMID: 16260759 PMCID: PMC2253238 DOI: 10.1110/ps.051671705] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Semisynthetic cephalosporins are synthesized from 7-amino cephalosporanic acid, which is produced by chemical deacylation or by a two-step enzymatic process of the natural antibiotic cephalosporin C. The known acylases take glutaryl-7-amino cephalosporanic acid as a primary substrate, and their specificity and activity are too low for cephalosporin C. Starting from a known glutaryl-7-amino cephalosporanic acid acylase as the protein scaffold, an acylase gene optimized for expression in Escherichia coli and for molecular biology manipulations was designed. Subsequently we used error-prone PCR mutagenesis, a molecular modeling approach combined with site-saturation mutagenesis, and site-directed mutagenesis to produce enzymes with a cephalosporin C/glutaryl-7-amino cephalosporanic acid catalytic efficiency that was increased up to 100-fold, and with a significant and higher maximal activity on cephalosporin C as compared to glutaryl-7-amino cephalosporanic acid (e.g., 3.8 vs. 2.7 U/mg protein, respectively, for the A215Y-H296S-H309S mutant). Our data in a bioreactor indicate an ~90% conversion of cephalosporin C to 7-amino-cephalosporanic acid in a single deacylation step. The evolved acylase variants we produced are enzymes with a new substrate specificity, not found in nature, and represent a hallmark for industrial production of 7-amino cephalosporanic acid.
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Affiliation(s)
- Loredano Pollegioni
- Dipartimento di Biotecnologie e Scienze Molecolari, Università degli Studi dell'Insubria, Via J.H. Dunant, 3, 21100 Varese, Italy.
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Michalska K, Brzezinski K, Jaskolski M. Crystal Structure of Isoaspartyl Aminopeptidase in Complex with l-Aspartate. J Biol Chem 2005; 280:28484-91. [PMID: 15946951 DOI: 10.1074/jbc.m504501200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The crystal structure of Escherichia coli isoaspartyl aminopeptidase/asparaginase (EcAIII), an enzyme belonging to the N-terminal nucleophile (Ntn)-hydrolases family, has been determined at 1.9-A resolution for a complex obtained by cocrystallization with l-aspartate, which is a product of both enzymatic reactions catalyzed by EcAIII. The enzyme is a dimer of heterodimers, (alphabeta)(2). The (alphabeta) heterodimer, which arises by autoproteolytic cleavage of the immature protein, exhibits an alphabetabetaalpha-sandwich fold, typical for Ntn-hydrolases. The asymmetric unit contains one copy of the EcAIII.Asp complex, with clearly visible l-aspartate ligands, one bound in each of the two active sites of the enzyme. The l-aspartate ligand is located near Thr(179), the N-terminal residue of subunit beta liberated in the autoproteolytic event. Structural comparisons with the free form of EcAIII reveal that there are no major rearrangements of the active site upon aspartate binding. Although the ligand binding mode is similar to that observed in an l-aspartate complex of the related enzyme human aspartylglucosaminidase, the architecture of the EcAIII active site sheds light on the question of substrate specificity and explains why EcAIII is not able to hydrolyze glycosylated asparagine substrates.
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Affiliation(s)
- Karolina Michalska
- Department of Crystallography, Faculty of Chemistry, A. Mickiewicz University, Poznan 60-780, Poland
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