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Abdolvahab MH, Safari M, Hasannejad F, Asefi N, Salimi A, Nazari M. Optimization of a recombinant BlaR-CTD protein formulation using the response surface methodology. J Biol Eng 2024; 18:4. [PMID: 38212764 PMCID: PMC10785353 DOI: 10.1186/s13036-023-00399-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 12/08/2023] [Indexed: 01/13/2024] Open
Abstract
The sequence of a carboxy-terminal of the β-lactam sensor-transducer protein (BlaR-CTD) from Bacillus licheniformis ATCC14580 was extracted from US7745193B2 patent and expressed in E. coli using pColdI vector as a soluble His-tag recombinant protein. In this study, several excipients were used to improve the stability of recombinant BlaR-CTD and obtain the optimal formulation for this protein using response surface methodology (RSM)/ Central Composite Design (CCD). Total protein concentration was measured by UV spectroscopy and the Bradford test. A total of 7 various factors were designed using four different excipients including Glycerol, Sucrose, Triton x-100, and Tween-20, and three different buffers like Tris, Borate, and PBS. By obtaining suitable excipients and buffer i.e. glycerol and sucrose, pH ranging from 7 to 9 were evaluated. The pH 7.62, glycerol 15.35%, and sucrose 152.52 mM were determined as the most suitable for improving the thermal stability of recombinant BlaR-CTD.
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Affiliation(s)
- Mohadeseh Haji Abdolvahab
- Recombinant Proteins Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran.
| | - Mojdeh Safari
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Farkhonde Hasannejad
- Genetic Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Nika Asefi
- Recombinant Proteins Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
- Genetic Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Alireza Salimi
- Department of Advanced Technologies, School of Medicine, North Khorasan University of Medical Science, Bojnurd, Iran
| | - Mahboobeh Nazari
- Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran
- Nanobiotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
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2
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Serchenya TS, Semizhon PA, Schaslionak AP, Harbachova IV, Vashkevich II, Sviridov OV. A Method for the Quantitative Determination of the Active Receptor of Beta-Lactam Antibiotics BlaR-CTD for Bioanalytical Applications. APPL BIOCHEM MICRO+ 2023. [DOI: 10.1134/s0003683823010106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2023]
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3
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Pandey D, Singhal N, Kumar M. Investigating the OXA Variants of ESKAPE Pathogens. Antibiotics (Basel) 2021; 10:antibiotics10121539. [PMID: 34943751 PMCID: PMC8699015 DOI: 10.3390/antibiotics10121539] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/20/2021] [Accepted: 10/21/2021] [Indexed: 11/16/2022] Open
Abstract
ESKAPE pathogens are the leading cause of nosocomial infections. The Global Priority List of WHO has categorized ESKAPE as priority 1 and 2 pathogens. Even though several mechanisms contribute to antimicrobial resistance, OXA β-lactamase has emerged as a new threat in combating nosocomial infections. In the present study we have investigated the presence of OXA and their variants, copy number, distribution on chromosomes/plasmids, subfamilies, phylogenetic relationships, amino acid identities and variabilities in ESKAPE pathogens. Our results revealed that a total of 929 OXA were present in 2258 completely assembled genomes, which could be further subdivided into 16 sub-families. Among all the ESKAPE pathogens, OXA were highly prevalent in A. baumannii, followed by P. aeruginosa and K. pneumoniae but completely absent in E. faecium and S. aureus while, only a few copies were found in Enterobacter spp. Most of the OXA variants belonged to the OXA-51-like subfamily (200 proteins), followed by OXA-50-like subfamily (189 proteins), OXA-23-like subfamily (156 proteins) and OXA-1-like subfamily (154 proteins). OXA-51-like, OXA-213-like, OXA-134-like, OXA-58-like, OXA-24-like and OXA-20-like subfamilies were present exclusively in A. baumannii. Phylogenetic tree of the subfamilies revealed that OXA-1-like and OXA-33-like, OXA-51-like and OXA-213-like and, OXA-5-like and OXA-10-like belonged to the same branches with amino acid identities as 100%, 97.10% and 80.90% respectively. This indicates that the members of these subfamily-pairs might have evolved from the same ancestor or have recently diverged. Thus, a judicious use of carbapenems is warranted to curtail the rise of new OXA enzymes and preserve them. This is the first detailed report about the OXA of ESKAPE pathogens.
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4
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Fisher JF, Mobashery S. β-Lactams against the Fortress of the Gram-Positive Staphylococcus aureus Bacterium. Chem Rev 2021; 121:3412-3463. [PMID: 33373523 PMCID: PMC8653850 DOI: 10.1021/acs.chemrev.0c01010] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The biological diversity of the unicellular bacteria-whether assessed by shape, food, metabolism, or ecological niche-surely rivals (if not exceeds) that of the multicellular eukaryotes. The relationship between bacteria whose ecological niche is the eukaryote, and the eukaryote, is often symbiosis or stasis. Some bacteria, however, seek advantage in this relationship. One of the most successful-to the disadvantage of the eukaryote-is the small (less than 1 μm diameter) and nearly spherical Staphylococcus aureus bacterium. For decades, successful clinical control of its infection has been accomplished using β-lactam antibiotics such as the penicillins and the cephalosporins. Over these same decades S. aureus has perfected resistance mechanisms against these antibiotics, which are then countered by new generations of β-lactam structure. This review addresses the current breadth of biochemical and microbiological efforts to preserve the future of the β-lactam antibiotics through a better understanding of how S. aureus protects the enzyme targets of the β-lactams, the penicillin-binding proteins. The penicillin-binding proteins are essential enzyme catalysts for the biosynthesis of the cell wall, and understanding how this cell wall is integrated into the protective cell envelope of the bacterium may identify new antibacterials and new adjuvants that preserve the efficacy of the β-lactams.
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Affiliation(s)
- Jed F Fisher
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame Indiana 46556, United States
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame Indiana 46556, United States
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5
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Liu Y, Li L, Yu F, Luo Y, Liang W, Yang Q, Wang R, Li M, Tang J, Gu Q, Luo Z, Chen M. Genome-wide analysis revealed the virulence attenuation mechanism of the fish-derived oral attenuated Streptococcus iniae vaccine strain YM011. FISH & SHELLFISH IMMUNOLOGY 2020; 106:546-554. [PMID: 32781206 DOI: 10.1016/j.fsi.2020.07.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 07/13/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
Streptococcus iniae has become one the most serious aquatic pathogens causing invasive diseases in farmed marine and freshwater fish worldwide, and orally attenuated vaccine is still the best option in protecting these invasive diseases. In this study, the safety, stability, immunogenicity of the S. iniae attenuated strain YM011 were evaluated, and comprehensively analyzed its virulence weakening mechanism at whole genome level. The results shown that attenuated S. iniae strain YM011 completely lost its pathogenicity to tilapia and had good immunogenicity with relative percent survival being 93.25% at 15 days and 90.31% at 30 days via IP injection, respectively, and 76.81% at 15 days and 56.69% at 30 days via oral gavage, respectively. Back-passage safety assay indicated that YM011 did not cause diseases or death in tilapia after 100 generations of serial passaging. Comparative genome-wide sequencing shown that YM011 had a 0.4 M large inversion fragment compared with its parental strain virulent strain GX005, which encoded 372 genes including drug resistance genes pbp2A and tet, as well as known virulence factors including hemolysin transport system gene, recA, and mutator family transposase. The attenuated S. iniae strain YM011 is an ideal attenuated oral vaccine candidate with good immunogenicity, safety and stability. Abnormal expression of important drug resistance genes as well as known virulence factors due to inversion of a 0.4 M large fragment is the leading mechanism underlying its attenuated virulence.
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Affiliation(s)
- Yu Liu
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Liping Li
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Fangzhao Yu
- Zhuhai Modern Agriculture Development Center, Zhuhai, 519000, China
| | - Yongju Luo
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Wanwen Liang
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Qiong Yang
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Rui Wang
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Min Li
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Jiayou Tang
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China
| | - Qunhong Gu
- Zhuhai Modern Agriculture Development Center, Zhuhai, 519000, China
| | - Zhiping Luo
- Zhuhai Modern Agriculture Development Center, Zhuhai, 519000, China
| | - Ming Chen
- Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning, 530021, China.
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Lautenschläger N, Popp PF, Mascher T. Development of a novel heterologous β-lactam-specific whole-cell biosensor in Bacillus subtilis. J Biol Eng 2020; 14:21. [PMID: 32765644 PMCID: PMC7394692 DOI: 10.1186/s13036-020-00243-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 07/16/2020] [Indexed: 11/10/2022] Open
Abstract
Background Whole-cell biosensors are a powerful and easy-to-use screening tool for the fast and sensitive detection of chemical compounds, such as antibiotics. β-Lactams still represent one of the most important antibiotic groups in therapeutic use. They interfere with late stages of the bacterial cell wall biosynthesis and result in irreversible perturbations of cell division and growth, ultimately leading to cell lysis. In order to simplify the detection of these antibiotics from solutions, solid media or directly from producing organisms, we aimed at developing a novel heterologous whole-cell biosensor in Bacillus subtilis, based on the β-lactam-induced regulatory system BlaR1/BlaI from Staphylococcus aureus. Results The BlaR1/BlaI system was heterologously expressed in B. subtilis and combined with the luxABCDE operon of Photorhabdus luminescens under control of the BlaR1/BlaI target promoter to measure the output of the biosensor. A combination of codon adaptation, constitutive expression of blaR1 and blaI and the allelic replacement of penP increased the inducer spectrum and dynamic range of the biosensor. β-Lactams from all four classes induced the target promoter PblaZ in a concentration-dependent manner, with a dynamic range of 7- to 53-fold. We applied our biosensor to a set of Streptomycetes soil isolates and demonstrated its potential to screen for the production of β-lactams. In addition to the successful implementation of a highly sensitive β-lactam biosensor, our results also provide the first experimental evidence to support previous suggestions that PenP functions as a β-lactamase in B. subtilis. Conclusion We have successfully established a novel heterologous whole-cell biosensor in B. subtilis that is highly sensitive for a broad spectrum of β-lactams from all four chemical classes. Therefore, it increases the detectable spectrum of compounds with respect to previous biosensor designs. Our biosensor can readily be applied for identifying β-lactams in liquid or on solid media, as well as for identifying potential β-lactam producers.
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Affiliation(s)
- Nina Lautenschläger
- Max Planck Unit for the Science of Pathogens, Berlin, Germany.,Institute of Microbiology, Technische Universität Dresden, Zellescher Weg 20b, 01217 Dresden, Germany
| | - Philipp F Popp
- Institute of Microbiology, Technische Universität Dresden, Zellescher Weg 20b, 01217 Dresden, Germany
| | - Thorsten Mascher
- Institute of Microbiology, Technische Universität Dresden, Zellescher Weg 20b, 01217 Dresden, Germany
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7
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Alexander JAN, Radaeva M, King DT, Chambers HF, Cherkasov A, Chatterjee SS, Strynadka NCJ. Structural analysis of avibactam-mediated activation of the bla and mec divergons in methicillin-resistant Staphylococcus aureus. J Biol Chem 2020; 295:10870-10884. [PMID: 32518158 DOI: 10.1074/jbc.ra120.013029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 06/02/2020] [Indexed: 02/01/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) infections cause significant mortality and morbidity globally. MRSA resistance to β-lactam antibiotics is mediated by two divergons that control levels of a β-lactamase, PC1, and a penicillin-binding protein poorly acylated by β-lactam antibiotics, PBP2a. Expression of genes encoding these proteins is controlled by two integral membrane proteins, BlaR1 and MecR1, which both have an extracellular β-lactam-binding sensor domain. Here, we solved the X-ray crystallographic structures of the BlaR1 and MecR1 sensor domains in complex with avibactam, a diazabicyclooctane β-lactamase inhibitor at 1.6-2.0 Å resolution. Additionally, we show that S. aureus SF8300, a clinically relevant strain from the USA300 clone of MRSA, responds to avibactam by up-regulating the expression of the blaZ and pbp2a antibiotic-resistance genes, encoding PC1 and PBP2a, respectively. The BlaR1-avibactam structure of the carbamoyl-enzyme intermediate revealed that avibactam is bound to the active-site serine in two orientations ∼180° to each other. Although a physiological role of the observed alternative pose remains to be validated, our structural results hint at the presence of a secondary sulfate-binding pocket that could be exploited in the design of future inhibitors of BlaR1/MecR1 sensor domains or the structurally similar class D β-lactamases. The MecR1-avibactam structure adopted a singular avibactam orientation similar to one of the two states observed in the BlaR1-avibactam structure. Given avibactam up-regulates expression of blaZ and pbp2a antibiotic resistance genes, we suggest further consideration and research is needed to explore what effects administering β-lactam-avibactam combinations have on treating MRSA infections.
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Affiliation(s)
- J Andrew N Alexander
- Department of Biochemistry and Molecular Biology and Centre for Blood Research, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Mariia Radaeva
- Vancouver Prostate Centre, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Dustin T King
- Department of Biochemistry and Molecular Biology and Centre for Blood Research, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Henry F Chambers
- Division of Infectious Disease, Dept. of Medicine, San Francisco General Hospital, San Francisco, California, USA
| | - Artem Cherkasov
- Vancouver Prostate Centre, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Som S Chatterjee
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland and Institute of Marine and Environmental Technology, Baltimore, Maryland, USA ;
| | - Natalie C J Strynadka
- Department of Biochemistry and Molecular Biology and Centre for Blood Research, The University of British Columbia, Vancouver, British Columbia, Canada ;
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Construction of an Electrochemical Receptor Sensor Based on Graphene/Thionine for the Sensitive Determination of β-Lactam Antibiotics Content in Milk. Int J Mol Sci 2020; 21:ijms21093306. [PMID: 32392795 PMCID: PMC7246818 DOI: 10.3390/ijms21093306] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 05/04/2020] [Accepted: 05/04/2020] [Indexed: 11/16/2022] Open
Abstract
In antibiotics, β-lactam is one kind of major concern acknowledged as an unavoidable contaminant in milk. Thus, a facile and sensitive method is essential for rapid β-lactam antibiotics detection. In our work, a specific electrochemical receptor sensor based on the graphene/thionine (GO/TH) composite was established. The mechanism of the electrochemical receptor sensor was a direct competitive inhibition of the binding of horseradish peroxidase-labeled ampicillin (HRP-AMP) to the mutant BlaR-CTD protein by free β-lactam antibiotics. Then, horseradish peroxidase (HRP) catalyzed the hydrolysis of the substrate hydrogen peroxide (H2O2), which produced an electrochemical signal. Under optimal experimental conditions, this method could quantitatively detect cefquinome from 0.1 to 8 μg L−1 and with the limit of detection (LOD) of 0.16 μg L−1, much lower than the maximum residue limit (MRL) of 5 μg L−1 set by the European Union. In addition, the LOD of spiked milk samples with cefalexin, cefquinoxime, cefotafur, penicillin G and ampicillin were 14.88 μg L−1, 2.46 μg L−1, 17.16 μg L−1, 0.06 μg L−1, 0.21 μg L−1 and the limits of quantitation (LOQ) were 36.09 μg L−1, 5.40 μg L−1, 41.45 μg L−1, 0.13 μg L−1, 0.42 μg L−1, respectively. The sensor showed a favorable recovery of 84.89–102.44%. Moreover, the electrochemical receptor sensor was successfully applied to assay β-lactam antibiotics in milk, which showed good correlation with the results obtained from liquid chromatography-tandem mass spectrometry (LC-MS/MS).
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9
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Fisher JF, Mobashery S. Constructing and deconstructing the bacterial cell wall. Protein Sci 2020; 29:629-646. [PMID: 31747090 PMCID: PMC7021008 DOI: 10.1002/pro.3737] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 12/11/2022]
Abstract
The history of modern medicine cannot be written apart from the history of the antibiotics. Antibiotics are cytotoxic secondary metabolites that are isolated from Nature. The antibacterial antibiotics disproportionately target bacterial protein structure that is distinct from eukaryotic protein structure, notably within the ribosome and within the pathways for bacterial cell-wall biosynthesis (for which there is not a eukaryotic counterpart). This review focuses on a pre-eminent class of antibiotics-the β-lactams, exemplified by the penicillins and cephalosporins-from the perspective of the evolving mechanisms for bacterial resistance. The mechanism of action of the β-lactams is bacterial cell-wall destruction. In the monoderm (single membrane, Gram-positive staining) pathogen Staphylococcus aureus the dominant resistance mechanism is expression of a β-lactam-unreactive transpeptidase enzyme that functions in cell-wall construction. In the diderm (dual membrane, Gram-negative staining) pathogen Pseudomonas aeruginosa a dominant resistance mechanism (among several) is expression of a hydrolytic enzyme that destroys the critical β-lactam ring of the antibiotic. The key sensing mechanism used by P. aeruginosa is monitoring the molecular difference between cell-wall construction and cell-wall deconstruction. In both bacteria, the resistance pathways are manifested only when the bacteria detect the presence of β-lactams. This review summarizes how the β-lactams are sensed and how the resistance mechanisms are manifested, with the expectation that preventing these processes will be critical to future chemotherapeutic control of multidrug resistant bacteria.
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Affiliation(s)
- Jed F. Fisher
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
| | - Shahriar Mobashery
- Department of Chemistry and BiochemistryUniversity of Notre DameSouth BendIndiana
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Ahmed S, Ning J, Cheng G, Maan MK, Chen T, Ahmad I, Algharib SA, Yuan Z. Development and validation of an enzyme-linked receptor assay based on mutant protein I188K/S19C/G24C for 40 beta-lactams antibiotics detection in 13 food samples. Microchem J 2020. [DOI: 10.1016/j.microc.2019.104354] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Mescola A, Dauvin M, Amoroso A, Duwez AS, Joris B. Single-molecule force spectroscopy to decipher the early signalling step in membrane-bound penicillin receptors embedded into a lipid bilayer. NANOSCALE 2019; 11:12275-12284. [PMID: 31211302 DOI: 10.1039/c9nr02466b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Understanding the molecular mechanism by which the signal of the presence of an antibiotic is transduced from outside to inside the bacterial cell is of fundamental interest for the β-lactam antibiotic resistance problem, but remains difficult to accomplish. No approach has ever addressed entire penicillin receptors in a membrane environment. Here we describe a method to investigate the purified Bacillus licheniformis BlaR1 receptor -a membrane-bound penicillin receptor involved in β-lactam resistance- embedded into a lipid bilayer in absence or presence of penicillin. By selecting a mutated receptor blocked in its signal transduction pathway just after its activation by penicillin, we revealed the very first step of receptor signalling by unfolding the receptor from its C-terminal end by AFM-based single-molecule force spectroscopy. We showed that the presence of the antibiotic entails significant conformational changes within the receptor. Our approach opens an avenue to study signal-transduction pathways mediated by membrane-bound proteins in a membrane environment.
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Affiliation(s)
- Andrea Mescola
- Molecular Systems, Department of Chemistry, University of Liège, 4000 Liège, Belgium.
| | - Marjorie Dauvin
- Bacterial physiology and genetics - Centre d'Ingénierie des Protéines-Integrative Biological Sciences, Department of Life Sciences, University of Liège, 4000 Liège, Belgium
| | - Ana Amoroso
- Bacterial physiology and genetics - Centre d'Ingénierie des Protéines-Integrative Biological Sciences, Department of Life Sciences, University of Liège, 4000 Liège, Belgium
| | - Anne-Sophie Duwez
- Molecular Systems, Department of Chemistry, University of Liège, 4000 Liège, Belgium.
| | - Bernard Joris
- Bacterial physiology and genetics - Centre d'Ingénierie des Protéines-Integrative Biological Sciences, Department of Life Sciences, University of Liège, 4000 Liège, Belgium
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12
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Ning J, Ahmed S, Cheng G, Chen T, Wang Y, Peng D, Yuan Z. Analysis of the stability and affinity of BlaR-CTD protein to β-lactam antibiotics based on docking and mutagenesis studies. J Biol Eng 2019; 13:27. [PMID: 30976316 PMCID: PMC6441189 DOI: 10.1186/s13036-019-0157-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 03/14/2019] [Indexed: 12/20/2022] Open
Abstract
Owing to the thermal instability and low affinity of BlaR-CTD to some β-lactams, the receptor assay based on BlaR-CTD is limited in the detection of abundant variety of drugs and the result is often unstable. In this study, the three-dimensional structure of BlaR-CTD from Bacillus licheniformis ATCC14580 was constructed by homologous modeling based on the crystal structure of BlaR-CTD from B. licheniformis 749/I, and the binding sites of this protein to 40 β-lactams were also obtained by molecular docking. To improve the stability and affinity of the protein, 23 mutant proteins were designed based on docking and homologous alignment results as well as by inserting disulfide bond and building the salt bridge. The mutation was rationality evaluated by SIFT and PloyPhen2 software. The heterologous expressed and purified mutant proteins were then subjected to the activity and stability assay. It was shown that among all mutant proteins, I188K/S19C/G24C, A138E/R50C/Q147C and S190Y/E183C/I188K respectively exhibited a higher affinity to 33, 22 and 21 β-lactams than the wild-type protein, while I188K/S19C/G24C exhibited the best stability. This may due to that the conformation of the active site in mutant protein I188K/S19C/G24C changed, and the random coli in the surface of protein activity increased. Our study suggests a possible structure-function relationship on the stability and affinity of BlaR-CTD, which provides new insights into protein rational design study and lays a solid foundation for establishing the receptor-based screening assay for the detection of β-lactam residues.
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Affiliation(s)
- Jianan Ning
- 1National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China
| | - Saeed Ahmed
- 1National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China
| | - Guyue Cheng
- 2MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
| | - Ting Chen
- 1National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China
| | - Yulian Wang
- 1National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China
| | - Dapeng Peng
- 1National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China
| | - Zonghui Yuan
- 1National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan, 430070 China.,2MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, 430070 China
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13
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Lohans CT, Wang DY, Jorgensen C, Cahill ST, Clifton IJ, McDonough MA, Oswin HP, Spencer J, Domene C, Claridge TDW, Brem J, Schofield CJ. 13C-Carbamylation as a mechanistic probe for the inhibition of class D β-lactamases by avibactam and halide ions. Org Biomol Chem 2018; 15:6024-6032. [PMID: 28678295 DOI: 10.1039/c7ob01514c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The class D (OXA) serine β-lactamases are a major cause of resistance to β-lactam antibiotics. The class D enzymes are unique amongst β-lactamases because they have a carbamylated lysine that acts as a general acid/base in catalysis. Previous crystallographic studies led to the proposal that β-lactamase inhibitor avibactam targets OXA enzymes in part by promoting decarbamylation. Similarly, halide ions are proposed to inhibit OXA enzymes via decarbamylation. NMR analyses, in which the carbamylated lysines of OXA-10, -23 and -48 were 13C-labelled, indicate that reaction with avibactam does not ablate lysine carbamylation in solution. While halide ions did not decarbamylate the 13C-labelled OXA enzymes in the absence of substrate or inhibitor, avibactam-treated OXA enzymes were susceptible to decarbamylation mediated by halide ions, suggesting halide ions may inhibit OXA enzymes by promoting decarbamylation of acyl-enzyme complex. Crystal structures of the OXA-10 avibactam complex were obtained with bromide, iodide, and sodium ions bound between Trp-154 and Lys-70. Structures were also obtained wherein bromide and iodide ions occupy the position expected for the 'hydrolytic water' molecule. In contrast with some solution studies, Lys-70 was decarbamylated in these structures. These results reveal clear differences between crystallographic and solution studies on the interaction of class D β-lactamases with avibactam and halides, and demonstrate the utility of 13C-NMR for studying lysine carbamylation in solution.
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Affiliation(s)
| | - David Y Wang
- Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
| | | | - Samuel T Cahill
- Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
| | - Ian J Clifton
- Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
| | | | - Henry P Oswin
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - James Spencer
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Carmen Domene
- Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK. and Department of Chemistry, King's College London, London, SE1 1DB, UK
| | | | - Jürgen Brem
- Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
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14
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Ahmed S, Ning J, Cheng G, Ahmad I, Li J, Mingyue L, Qu W, Iqbal M, Shabbir MAB, Yuan Z. Receptor-based screening assays for the detection of antibiotics residues - A review. Talanta 2017; 166:176-186. [PMID: 28213220 DOI: 10.1016/j.talanta.2017.01.057] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 01/14/2017] [Accepted: 01/20/2017] [Indexed: 12/24/2022]
Abstract
Consumer and regulatory agencies have a high concern to antibiotic residues in food producing animals, so appropriate screening assays of fast, sensitive, low cost, and easy sample preparation for the identification of these residues are essential for the food-safety insurance. Great efforts in the development of a high-throughput antibiotic screening assay have been made in recent years. Concerning the screening of antibiotic residue, this review elaborate an overview on the availability, advancement and applicability of antibiotic receptor based screening assays for the safety assessment of antibiotics usage (i.e. radio receptor assay, enzyme labeling assays, colloidal gold receptor assay, enzyme colorimetry assay and biosensor assay). This manuscript also tries to shed a light on the selection, preparation and future perspective of receptor protein for antibiotic residue detection. These assays have been introduced for the screening of numerous food samples. Receptor based screening technology for antibiotic detection has high accuracy. It has been concluded that at the same time, it can detect a class of drugs for certain receptor, and realize the multi-residue detection. These assays offer fast, easy and precise detection of antibiotics.
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Affiliation(s)
- Saeed Ahmed
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China
| | - Jianan Ning
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China
| | - Guyue Cheng
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China
| | - Ijaz Ahmad
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China; The University of Agriculture Peshawar, Pakistan
| | - Jun Li
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China
| | - Liu Mingyue
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China
| | - Wei Qu
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China
| | - Mujahid Iqbal
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China
| | - M A B Shabbir
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China
| | - Zonghui Yuan
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MOA Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University, Wuhan 430070, China; MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan 430070, China.
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15
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Ngo TD, Ryu BH, Ju H, Jang EJ, Kim KK, Kim TD. Crystallographic analysis and biochemical applications of a novel penicillin-binding protein/β-lactamase homologue from a metagenomic library. ACTA ACUST UNITED AC 2014; 70:2455-66. [PMID: 25195758 DOI: 10.1107/s1399004714015272] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 06/29/2014] [Indexed: 11/10/2022]
Abstract
Interest in penicillin-binding proteins and β-lactamases (the PBP-βL family) is increasing owing to their biological and clinical significance. In this study, the crystal structure of Est-Y29, a metagenomic homologue of the PBP-βL family, was determined at 1.7 Å resolution. In addition, complex structures of Est-Y29 with 4-nitrophenyl phosphate (4NP) and with diethyl phosphonate (DEP) at 2.0 Å resolution were also elucidated. Structural analyses showed that Est-Y29 is composed of two domains: a β-lactamase fold and an insertion domain. A deep hydrophobic patch between these domains defines a wide active site, and a nucleophilic serine (Ser58) residue is located in a groove defined primarily by hydrophobic residues between the two domains. In addition, three hydrophobic motifs, which make up the substrate-binding site, allow this enzyme to hydrolyze a wide variety of hydrophobic compounds, including fish and olive oils. Furthermore, cross-linked Est-Y29 aggregates (CLEA-Est-Y29) significantly increase the stability of the enzyme as well as its potential for extensive reuse in various deactivating conditions. The structural features of Est-Y29, together with biochemical and biophysical studies, could provide a molecular basis for understanding the properties and regulatory mechanisms of the PBP-βL family and their potential for use in industrial biocatalysts.
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Affiliation(s)
- Tri Duc Ngo
- Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon 440-746, Republic of Korea
| | - Bum Han Ryu
- Department of Applied Chemistry and Biological Engineering, College of Engineering, Ajou University, Suwon 443-749, Republic of Korea
| | - Hansol Ju
- Department of Applied Chemistry and Biological Engineering, College of Engineering, Ajou University, Suwon 443-749, Republic of Korea
| | - Eun Jin Jang
- Department of Applied Chemistry and Biological Engineering, College of Engineering, Ajou University, Suwon 443-749, Republic of Korea
| | - Kyeong Kyu Kim
- Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon 440-746, Republic of Korea
| | - T Doohun Kim
- Department of Applied Chemistry and Biological Engineering, College of Engineering, Ajou University, Suwon 443-749, Republic of Korea
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16
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Che T, Bethel CR, Pusztai-Carey M, Bonomo RA, Carey PR. The different inhibition mechanisms of OXA-1 and OXA-24 β-lactamases are determined by the stability of active site carboxylated lysine. J Biol Chem 2014; 289:6152-64. [PMID: 24443569 DOI: 10.1074/jbc.m113.533562] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The catalytic efficiency of class D β-lactamases depends critically on an unusual carboxylated lysine as the general base residue for both the acylation and deacylation steps of the enzyme. Microbiological and biochemical studies on the class D β-lactamases OXA-1 and OXA-24 showed that the two enzymes behave differently when reacting with two 6-methylidene penems (penem 1 and penem 3): the penems are good inhibitors of OXA-1 but act more like substrates for OXA-24. UV difference and Raman spectroscopy revealed that the respective reaction mechanisms are different. The penems form an unusual intermediate, a 1,4-thiazepine derivative in OXA-1, and undergo deacylation followed by the decarboxylation of Lys-70, rendering OXA-1 inactive. This inactivation could not be reversed by the addition of 100 mM NaHCO3. In OXA-24, under mild conditions (enzyme:inhibitor = 1:4), only hydrolyzed products were detected, and the enzyme remained active. However, under harsh conditions (enzyme:inhibitor = 1:2000), OXA-24 was inhibited via decarboxylation of Lys-84; however, the enzyme could be reactivated by the addition of 100 mM NaHCO3. We conclude that OXA-24 not only decarboxylates with difficulty but also recarboxylates with ease; in contrast, OXA-1 decarboxylates easily but recarboxylates with difficulty. Structural analysis of the active site indicates that a crystallographic water molecule may play an important role in carboxylation in OXA-24 (an analogous water molecule is not found in OXA-1), supporting the suggestion that a water molecule in the active site of OXA-24 can lower the energy barrier for carboxylation significantly.
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Affiliation(s)
- Tao Che
- From the Departments of Biochemistry
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17
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Leonard DA, Bonomo RA, Powers RA. Class D β-lactamases: a reappraisal after five decades. Acc Chem Res 2013; 46:2407-15. [PMID: 23902256 DOI: 10.1021/ar300327a] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Despite 70 years of clinical use, β-lactam antibiotics still remain at the forefront of antimicrobial chemotherapy. The major challenge to these life-saving therapeutics is the presence of bacterial enzymes (i.e., β-lactamases) that can hydrolyze the β-lactam bond and inactivate the antibiotic. These enzymes can be grouped into four classes (A-D). Among the most genetically diverse are the class D β-lactamases. In this class are β-lactamases that can inactivate the entire spectrum of β-lactam antibiotics (penicillins, cephalosporins, and carbapenems). Class D β-lactamases are mostly found in Gram-negative bacteria such as Pseudomonas aeruginosa , Escherichia coli , Proteus mirabilis , and Acinetobacter baumannii . The active-sites of class D β-lactamases contain an unusual N-carboxylated lysine post-translational modification. A strongly hydrophobic active-site helps create the conditions that allow the lysine to combine with CO2, and the resulting carbamate is stabilized by a number of hydrogen bonds. The carboxy-lysine plays a symmetric role in the reaction, serving as a general base to activate the serine nucleophile in the acylation reaction, and the deacylating water in the second step. There are more than 250 class D β-lactamases described, and the full set of variants shows remarkable diversity with regard to substrate binding and turnover. Narrow-spectrum variants are most effective against the earliest generation penicillins and cephalosporins such as ampicillin and cephalothin. Extended-spectrum variants (also known as extended-spectrum β-lactamases, ESBLs) pose a more dangerous clinical threat as they possess a small number of substitutions that allow them to bind and hydrolyze later generation cephalosporins that contain bulkier side-chain constituents (e.g., cefotaxime, ceftazidime, and cefepime). Mutations that permit this versatility seem to cluster in the area surrounding an active-site tryptophan resulting in a widened active-site to accommodate the oxyimino side-chains of these cephalosporins. More concerning are the class D β-lactamases that hydrolyze clinically important carbapenem β-lactam drugs (e.g., imipenem). Whereas carbapenems irreversibly acylate and inhibit narrow-spectrum β-lactamases, class D carbapenemases are able to recruit and activate a deacylating water. The rotational orientation of the C6 hydroxyethyl group found on all carbapenem antibiotics likely plays a role in whether the deacylating water is effective or not. Inhibition of class D β-lactamases is a current challenge. Commercially available inhibitors that are active against other classes of β-lactamases are ineffective against class D enzymes. On the horizon are several compounds, consisting of both β-lactam derivatives and non-β-lactams, that have the potential of providing novel leads to design new mechanism-based inactivators that are effective against the class D enzymes. Several act synergistically when given in combination with a β-lactam antibiotic, and others show a unique mechanism of inhibition that is distinct from the traditional β-lactamase inhibitors. These studies will bolster structure-based inhibitor design efforts to facilitate the optimization and development of these compounds as class D inactivators.
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Affiliation(s)
- David A. Leonard
- Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401, United States
| | - Robert A. Bonomo
- Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, and Department of Pharmacology, Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, United States
| | - Rachel A. Powers
- Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401, United States
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18
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Peng J, Cheng G, Huang L, Wang Y, Hao H, Peng D, Liu Z, Yuan Z. Development of a direct ELISA based on carboxy-terminal of penicillin-binding protein BlaR for the detection of β-lactam antibiotics in foods. Anal Bioanal Chem 2013; 405:8925-33. [DOI: 10.1007/s00216-013-7311-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Revised: 08/01/2013] [Accepted: 08/15/2013] [Indexed: 11/28/2022]
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19
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2-Nitrobenzyl Esters of Penam and Cephem Derivatives as Inhibitors of Penicillin-Binding Proteins. ASIAN J ORG CHEM 2013. [DOI: 10.1002/ajoc.201300108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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20
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López-Pelegrín M, Cerdà-Costa N, Martínez-Jiménez F, Cintas-Pedrola A, Canals A, Peinado JR, Marti-Renom MA, López-Otín C, Arolas JL, Gomis-Rüth FX. A novel family of soluble minimal scaffolds provides structural insight into the catalytic domains of integral membrane metallopeptidases. J Biol Chem 2013; 288:21279-21294. [PMID: 23733187 PMCID: PMC3774397 DOI: 10.1074/jbc.m113.476580] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 05/13/2013] [Indexed: 11/06/2022] Open
Abstract
In the search for structural models of integral-membrane metallopeptidases (MPs), we discovered three related proteins from thermophilic prokaryotes, which we grouped into a novel family called "minigluzincins." We determined the crystal structures of the zymogens of two of these (Pyrococcus abyssi proabylysin and Methanocaldococcus jannaschii projannalysin), which are soluble and, with ∼100 residues, constitute the shortest structurally characterized MPs to date. Despite relevant sequence and structural similarity, the structures revealed two unique mechanisms of latency maintenance through the C-terminal segments previously unseen in MPs as follows: intramolecular, through an extended tail, in proabylysin, and crosswise intermolecular, through a helix swap, in projannalysin. In addition, structural and sequence comparisons revealed large similarity with MPs of the gluzincin tribe such as thermolysin, leukotriene A4 hydrolase relatives, and cowrins. Noteworthy, gluzincins mostly contain a glutamate as third characteristic zinc ligand, whereas minigluzincins have a histidine. Sequence and structural similarity further allowed us to ascertain that minigluzincins are very similar to the catalytic domains of integral membrane MPs of the MEROPS database families M48 and M56, such as FACE1, HtpX, Oma1, and BlaR1/MecR1, which are provided with trans-membrane helices flanking or inserted into a minigluzincin-like catalytic domain. In a time where structural biochemistry of integral-membrane proteins in general still faces formidable challenges, the minigluzincin soluble minimal scaffold may contribute to our understanding of the working mechanisms of these membrane MPs and to the design of novel inhibitors through structure-aided rational drug design approaches.
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Affiliation(s)
- Mar López-Pelegrín
- From the Proteolysis Laboratory, Department of Structural Biology, Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas, c/Baldiri Reixac, 15-21, 08028 Barcelona
| | - Núria Cerdà-Costa
- From the Proteolysis Laboratory, Department of Structural Biology, Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas, c/Baldiri Reixac, 15-21, 08028 Barcelona
| | - Francisco Martínez-Jiménez
- the Genome Biology Group, Centre Nacional d'Anàlisi Genòmic, c/Baldiri Reixac, 4, 08028 Barcelona,; the Gene Regulation, Stem Cells and Cancer Program, Center for Genomic Regulation, c/Dr. Aiguader, 88, 08003 Barcelona
| | - Anna Cintas-Pedrola
- From the Proteolysis Laboratory, Department of Structural Biology, Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas, c/Baldiri Reixac, 15-21, 08028 Barcelona
| | - Albert Canals
- the Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas and Institute for Research in Biomedicine, c/Baldiri Reixac, 10-12, 08028 Barcelona, and
| | - Juan R Peinado
- From the Proteolysis Laboratory, Department of Structural Biology, Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas, c/Baldiri Reixac, 15-21, 08028 Barcelona
| | - Marc A Marti-Renom
- the Genome Biology Group, Centre Nacional d'Anàlisi Genòmic, c/Baldiri Reixac, 4, 08028 Barcelona,; the Gene Regulation, Stem Cells and Cancer Program, Center for Genomic Regulation, c/Dr. Aiguader, 88, 08003 Barcelona
| | - Carlos López-Otín
- the Departamento de Bioquímica y Biología Molecular and Instituto Universitario de Oncología, Universidad de Oviedo, 33006 Oviedo, Spain
| | - Joan L Arolas
- From the Proteolysis Laboratory, Department of Structural Biology, Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas, c/Baldiri Reixac, 15-21, 08028 Barcelona,.
| | - F Xavier Gomis-Rüth
- From the Proteolysis Laboratory, Department of Structural Biology, Molecular Biology Institute of Barcelona, Consejo Superior de Investigaciones Científicas, c/Baldiri Reixac, 15-21, 08028 Barcelona,.
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21
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Arêde P, Botelho T, Guevara T, Usón I, Oliveira DC, Gomis-Rüth FX. Structure-function studies of the staphylococcal methicillin resistance antirepressor MecR2. J Biol Chem 2013; 288:21267-21278. [PMID: 23733184 DOI: 10.1074/jbc.m112.448134] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Methicillin resistance in Staphylococcus aureus is elicited by the MecI-MecR1-MecA axis encoded by the mec locus. Recently, MecR2 was also identified as a regulator of mec through binding of the methicillin repressor, MecI. Here we show that plasmid-encoded full-length MecR2 restores resistance in a sensitive S. aureus mecR2 deletion mutant of the resistant strain N315. The crystal structure of MecR2 reveals an N-terminal DNA-binding domain, an intermediate scaffold domain, and a C-terminal dimerization domain that contributes to oligomerization. The protein shows structural similarity to ROK (repressors, open reading frames, and kinases) family proteins, which bind DNA and/or sugar molecules. We found that functional cell-based assays of three point mutants affecting residues participating in sugar binding in ROK proteins had no effect on the resistance phenotype. By contrast, MecR2 bound short double-stranded DNA oligonucleotides nonspecifically, and a deletion mutant affecting the N-terminal DNA-binding domain showed a certain effect on activity, thus contributing to resistance less than the wild-type protein. Similarly, a deletion mutant, in which a flexible segment of intermediate scaffold domain had been replaced by four glycines, significantly reduced MecR2 function, thus indicating that this domain may likewise be required for activity. Taken together, these results provide the structural basis for the activity of a methicillin antirepressor, MecR2, which would sequester MecI away from its cognate promoter region and facilitate its degradation.
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Affiliation(s)
- Pedro Arêde
- the Center for Microbiological Resources, Department of Life Sciences, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, P-2829-516 Caparica, Portugal, and
| | - Tiago Botelho
- From the Proteolysis Lab, Department of Structural Biology, Molecular Biology Institute of Barcelona, CSIC, E-08028 Barcelona, Catalonia, Spain
| | - Tibisay Guevara
- From the Proteolysis Lab, Department of Structural Biology, Molecular Biology Institute of Barcelona, CSIC, E-08028 Barcelona, Catalonia, Spain
| | - Isabel Usón
- the Institució Catalana de Recerca i Estudis Avançats, Molecular Biology Institute of Barcelona, CSIC, Barcelona Science Park, E-08028 Barcelona, Catalonia, Spain
| | - Duarte C Oliveira
- the Center for Microbiological Resources, Department of Life Sciences, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, P-2829-516 Caparica, Portugal, and
| | - F Xavier Gomis-Rüth
- From the Proteolysis Lab, Department of Structural Biology, Molecular Biology Institute of Barcelona, CSIC, E-08028 Barcelona, Catalonia, Spain,.
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22
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Favre A, Grugier J, Brans A, Joris B, Marchand-Brynaert J. 6-Aminopenicillanic acid (6-APA) derivatives equipped with anchoring arms. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.10.100] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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23
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Berzigotti S, Benlafya K, Sépulchre J, Amoroso A, Joris B. Bacillus licheniformis BlaR1 L3 loop is a zinc metalloprotease activated by self-proteolysis. PLoS One 2012; 7:e36400. [PMID: 22623956 PMCID: PMC3356374 DOI: 10.1371/journal.pone.0036400] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 04/04/2012] [Indexed: 11/26/2022] Open
Abstract
In Bacillus licheniformis 749/I, BlaP β-lactamase is induced by the presence of a β-lactam antibiotic outside the cell. The first step in the induction mechanism is the detection of the antibiotic by the membrane-bound penicillin receptor BlaR1 that is composed of two functional domains: a carboxy-terminal domain exposed outside the cell, which acts as a penicillin sensor, and an amino-terminal domain anchored to the cytoplasmic membrane, which works as a transducer-transmitter. The acylation of BlaR1 sensor domain by the antibiotic generates an intramolecular signal that leads to the activation of the L3 cytoplasmic loop of the transmitter by a single-point cleavage. The exact mechanism of L3 activation and the nature of the secondary cytoplasmic signal launched by the activated transmitter remain unknown. However, these two events seem to be linked to the presence of a HEXXH zinc binding motif of neutral zinc metallopeptidases. By different experimental approaches, we demonstrated that the L3 loop binds zinc ion, belongs to Gluzincin metallopeptidase superfamily and is activated by self-proteolysis.
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Affiliation(s)
- Stéphanie Berzigotti
- Centre for Protein Engineering, Department of Life Sciences, University of Liège, Liège, Belgium
| | - Kamal Benlafya
- Centre for Protein Engineering, Department of Life Sciences, University of Liège, Liège, Belgium
| | - Jérémy Sépulchre
- Centre for Protein Engineering, Department of Life Sciences, University of Liège, Liège, Belgium
| | - Ana Amoroso
- Centre for Protein Engineering, Department of Life Sciences, University of Liège, Liège, Belgium
| | - Bernard Joris
- Centre for Protein Engineering, Department of Life Sciences, University of Liège, Liège, Belgium
- * E-mail:
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24
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Buchman JS, Schneider KD, Lloyd AR, Pavlish SL, Leonard DA. Site-saturation mutagenesis of position V117 in OXA-1 β-lactamase: effect of side chain polarity on enzyme carboxylation and substrate turnover. Biochemistry 2012; 51:3143-50. [PMID: 22429123 DOI: 10.1021/bi201896k] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Class D β-lactamases pose an emerging threat to the efficacy of β-lactam therapy for bacterial infections. Class D enzymes differ mechanistically from other β-lactamases by the presence of an active-site N-carboxylated lysine that serves as a general base to activate the serine nucleophile for attack. We have used site-saturation mutagenesis at position V117 in the class D β-lactamase OXA-1 to investigate how alterations in the environment around N-carboxylated K70 affect the ability of that modified residue to carry out its normal function. Minimum inhibitory concentration analysis of the 20 position 117 variants demonstrates a clear pattern of charge and polarity effects on the level of ampicillin resistance imparted on Escherichia coli (E. coli). Substitutions that introduce a negative charge (D, E) at position 117 reduce resistance to near background levels, while the positively charged K and R residues maintain the highest resistance levels of all mutants. Treatment of the acidic variants with the fluorescent penicillin BOCILLIN FL followed by SDS-PAGE shows that they are active for acylation by substrate but deacylation-deficient. We used a novel fluorescence anisotropy assay to show that the specific charge and hydrogen-bonding potential of the residue at position 117 affect CO(2) binding to K70, which in turn correlates to deacylation activity. These conclusions are discussed in light of the mechanisms proposed for both class D β-lactamases and BlaR β-lactam sensor proteins and suggest a reason for the preponderance of asparagine at the V117-homologous position in the sensors.
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Affiliation(s)
- Jennifer S Buchman
- Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401, USA
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25
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Borbulevych O, Kumarasiri M, Wilson B, Llarrull LI, Lee M, Hesek D, Shi Q, Peng J, Baker BM, Mobashery S. Lysine Nzeta-decarboxylation switch and activation of the beta-lactam sensor domain of BlaR1 protein of methicillin-resistant Staphylococcus aureus. J Biol Chem 2011; 286:31466-72. [PMID: 21775440 DOI: 10.1074/jbc.m111.252189] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The integral membrane protein BlaR1 of methicillin-resistant Staphylococcus aureus senses the presence of β-lactam antibiotics in the milieu and transduces the information to the cytoplasm, where the biochemical events that unleash induction of antibiotic resistance mechanisms take place. We report herein by two-dimensional and three-dimensional NMR experiments of the sensor domain of BlaR1 in solution and by determination of an x-ray structure for the apo protein that Lys-392 of the antibiotic-binding site is posttranslationally modified by N(ζ)-carboxylation. Additional crystallographic and NMR data reveal that on acylation of Ser-389 by antibiotics, Lys-392 experiences N(ζ)-decarboxylation. This unique process, termed the lysine N(ζ)-decarboxylation switch, arrests the sensor domain in the activated ("on") state, necessary for signal transduction and all the subsequent biochemical processes. We present structural information on how this receptor activation process takes place, imparting longevity to the antibiotic-receptor complex that is needed for the induction of the antibiotic-resistant phenotype in methicillin-resistant S. aureus.
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Affiliation(s)
- Oleg Borbulevych
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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26
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Three factors that modulate the activity of class D β-lactamases and interfere with the post-translational carboxylation of Lys70. Biochem J 2011; 432:495-504. [PMID: 21108605 DOI: 10.1042/bj20101122] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The activity of class D β-lactamases is dependent on Lys70 carboxylation in the active site. Structural, kinetic and affinity studies show that this post-translational modification can be affected by the presence of a poor substrate such as moxalactam but also by the V117T substitution. Val117 is a strictly conserved hydrophobic residue located in the active site. In addition, inhibition of class D β-lactamases by chloride ions is due to a competition between the side chain carboxylate of the modified Lys70 and chloride ions. Determination of the individual kinetic constants shows that the deacylation of the acyl-enzyme is the rate-limiting step for the wild-type OXA-10 β-lactamase.
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27
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Bou G, Santillana E, Sheri A, Beceiro A, Sampson J, Kalp M, Bethel CR, Distler AM, Drawz SM, Pagadala SRR, van den Akker F, Bonomo RA, Romero A, Buynak JD. Design, synthesis, and crystal structures of 6-alkylidene-2'-substituted penicillanic acid sulfones as potent inhibitors of Acinetobacter baumannii OXA-24 carbapenemase. J Am Chem Soc 2010; 132:13320-31. [PMID: 20822105 PMCID: PMC3393087 DOI: 10.1021/ja104092z] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Class D β-lactamases represent a growing and diverse class of penicillin-inactivating enzymes that are usually resistant to commercial β-lactamase inhibitors. As many such enzymes are found in multi-drug resistant (MDR) Acinetobacter baumannii and Pseudomonas aeruginosa, novel β-lactamase inhibitors are urgently needed. Five unique 6-alkylidene-2'-substituted penicillanic acid sulfones (1-5) were synthesized and tested against OXA-24, a clinically important β-lactamase that inactivates carbapenems and is found in A. baumannii. Based upon the roles Tyr112 and Met223 play in the OXA-24 β-lactamase, we also engineered two variants (Tyr112Ala and Tyr112Ala,Met223Ala) to test the hypothesis that the hydrophobic tunnel formed by these residues influences inhibitor recognition. IC(50) values against OXA-24 and two OXA-24 β-lactamase variants ranged from 10 ± 1 (4 vs WT) to 338 ± 20 nM (5 vs Tyr112Ala, Met223Ala). Compound 4 possessed the lowest K(i) (500 ± 80 nM vs WT), and 1 possessed the highest inactivation efficiency (k(inact)/K(i) = 0.21 ± 0.02 μM(-1) s(-1)). Electrospray ionization mass spectrometry revealed a single covalent adduct, suggesting the formation of an acyl-enzyme intermediate. X-ray structures of OXA-24 complexed to four inhibitors (2.0-2.6 Å) reveal the formation of stable bicyclic aromatic intermediates with their carbonyl oxygen in the oxyanion hole. These data provide the first structural evidence that 6-alkylidene-2'-substituted penicillin sulfones are effective mechanism-based inactivators of class D β-lactamases. Their unique chemistry makes them developmental candidates. Mechanisms for class D hydrolysis and inhibition are discussed, and a pathway for the evolution of the BlaR1 sensor of Staphylococcus aureus to the class D β-lactamases is proposed.
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Affiliation(s)
| | | | | | | | - Jared Sampson
- Departments of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, OH
| | - Matthew Kalp
- Departments of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, OH
| | | | - Anne M. Distler
- Department of Pharmacology, Case Western Reserve University School of Medicine
| | - Sarah M. Drawz
- Department of Pathology, Case Western Reserve University School of Medicine
| | | | - Focco van den Akker
- Departments of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, OH
| | - Robert A. Bonomo
- Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH
- Department of Pharmacology, Case Western Reserve University School of Medicine
- Department of Molecular Biology and Microbiology, Case Western Reserve University
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28
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Affiliation(s)
- Jed F Fisher
- Department of Chemistry and Biochemistry, 423 Nieuwland Science Hall, Notre Dame, Indiana 46556-5670, USA
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29
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Schneider KD, Bethel CR, Distler AM, Hujer AM, Bonomo RA, Leonard DA. Mutation of the active site carboxy-lysine (K70) of OXA-1 beta-lactamase results in a deacylation-deficient enzyme. Biochemistry 2009; 48:6136-45. [PMID: 19485421 DOI: 10.1021/bi900448u] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Class D beta-lactamases hydrolyze beta-lactam antibiotics by using an active site serine nucleophile to form a covalent acyl-enzyme intermediate and subsequently employ water to deacylate the beta-lactam and release product. Class D beta-lactamases are carboxylated on the epsilon-amino group of an active site lysine, with the resulting carbamate functional group serving as a general base. We discovered that substitutions of the active site serine and lysine in OXA-1 beta-lactamase, a monomeric class D enzyme, significantly disrupt catalytic turnover. Substitution of glycine for the nucleophilic serine (S67G) results in an enzyme that can still bind substrate but is unable to form a covalent acyl-enzyme intermediate. Substitution of the carboxylated lysine (K70), on the other hand, results in enzyme that can be acylated by substrate but is impaired with respect to deacylation. We employed the fluorescent penicillin BOCILLIN FL to show that three different substitutions for K70 (alanine, aspartate, and glutamate) lead to the accumulation of significant acyl-enzyme intermediate. Interestingly, BOCILLIN FL deacylation rates (t(1/2)) vary depending on the identity of the substituting residue, from approximately 60 min for K70A to undetectable deacylation for K70D. Tryptophan fluorescence spectroscopy was used to confirm that these results are applicable to natural (i.e., nonfluorescent) substrates. Deacylation by K70A, but not K70D or K70E, can be partially restored by the addition of short-chain carboxylic acid mimetics of the lysine carbamate. In conclusion, we establish the functional role of the carboxylated lysine in OXA-1 and highlight its specific role in acylation and deacylation.
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Affiliation(s)
- Kyle D Schneider
- Department of Chemistry, Grand Valley State University, Allendale, Michigan 49401, USA
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30
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Devouge S, Conti J, Goldsztein A, Gosselin E, Brans A, Voué M, De Coninck J, Homblé F, Goormaghtigh E, Marchand-Brynaert J. Surface functionalization of germanium ATR devices for use in FTIR-biosensors. J Colloid Interface Sci 2008; 332:408-15. [PMID: 19150721 DOI: 10.1016/j.jcis.2008.12.045] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Revised: 12/01/2008] [Accepted: 12/17/2008] [Indexed: 11/25/2022]
Abstract
Biosensors based on intrinsic detection methods have attracted growing interest. The use of Fourier transform infra-red (FTIR) spectroscopy with the attenuated internal total reflection (ATR) mode, in the biodetection context, requires appropriate surface functionalization of the ATR optical element. Here, we report the direct grafting of a thin organic layer (about 20 A depth) on the surface of a germanium crystal. This covering, constructed with novel amphiphilic molecules 2b (namely, 2,5,8,11,14,17,20-heptaoxadocosan-22-yl-3-(triethoxysilyl) propylcarbamate), is stable for several hours under phosphate buffered saline (PBS) flux and features protein-repulsive properties. Photografting of molecule 5 (namely, O-succinimidyl 4-(p-azidophenyl)butanoate) affords the activated ATR element, ready for the covalent fixation of receptors, penicillin recognizing proteins BlaR-CTD for instance. The different steps of the previous construction have been monitored by water contact angle (theta(w)) measurements, spectroscopic ellipsometry (covering depth), X-ray photoelectron spectroscopy (XPS) by using a fluorinated tag for the control of surface reactivity, and FTIR-ATR spectroscopy for the structural analysis of grafted molecules. Indeed, contrarily to silicon device, germanium device offers a broad spectral window (1000-4000 cm(-1)) and thus amide I and II absorption bands can be recorded. This work lays the foundations for the construction of novel FTIR biosensors.
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Affiliation(s)
- Sabrina Devouge
- Unité de Chimie Organique et Médicinale, Université Catholique de Louvain, Bâtiment Lavoisier, Place Louis Pasteur 1, B-1348 Louvain-la-Neuve, Belgium
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31
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The role of OXA-1 beta-lactamase Asp(66) in the stabilization of the active-site carbamate group and in substrate turnover. Biochem J 2008; 410:455-62. [PMID: 18031291 DOI: 10.1042/bj20070573] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The OXA-1 beta-lactamase is one of the few class D enzymes that has an aspartate residue at position 66, a position that is proximal to the active-site residue Ser(67). In class A beta-lactamases, such as TEM-1 and SHV-1, residues adjacent to the active-site serine residue play a crucial role in inhibitor resistance and substrate selectivity. To probe the role of Asp(66) in substrate affinity and catalysis, we performed site-saturation mutagenesis at this position. Ampicillin MIC (minimum inhibitory concentration) values for the full set of Asp(66) mutants expressed in Escherichia coli DH10B ranged from < or =8 microg/ml for cysteine, proline and the basic amino acids to > or =256 microg/ml for asparagine, leucine and the wild-type aspartate. Replacement of aspartic acid by asparagine at position 66 also led to a moderate enhancement of extended-spectrum cephalosporin resistance. OXA-1 shares with other class D enzymes a carboxylated residue, Lys(70), that acts as a general base in the catalytic mechanism. The addition of 25 mM bicarbonate to Luria-Bertani-broth agar resulted in a > or =16-fold increase in MICs for most OXA-1 variants with amino acid replacements at position 66 when expressed in E. coli. Because Asp(66) forms hydrogen bonds with several other residues in the OXA-1 active site, we propose that this residue plays a role in stabilizing the CO2 bound to Lys(70) and thereby profoundly affects substrate turnover.
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32
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Jordan S, Hutchings MI, Mascher T. Cell envelope stress response in Gram-positive bacteria. FEMS Microbiol Rev 2008; 32:107-46. [PMID: 18173394 DOI: 10.1111/j.1574-6976.2007.00091.x] [Citation(s) in RCA: 268] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Sina Jordan
- Department of General Microbiology, Georg-August-University, Grisebachstrasse 8, Göttingen, Germany
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33
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Marrero A, Mallorquí-Fernández G, Guevara T, García-Castellanos R, Gomis-Rüth FX. Unbound and acylated structures of the MecR1 extracellular antibiotic-sensor domain provide insights into the signal-transduction system that triggers methicillin resistance. J Mol Biol 2006; 361:506-21. [PMID: 16846613 DOI: 10.1016/j.jmb.2006.06.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2006] [Revised: 06/15/2006] [Accepted: 06/16/2006] [Indexed: 11/25/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) strains are responsible for most hospital-onset bacterial infections. Lately, they have become a major threat to the community through infections of skin, soft tissue and respiratory tract, and subsequent septicaemia or septic shock. MRSA strains are resistant to most beta-lactam antibiotics (BLAs) as a result of the biosynthesis of a penicillin-binding protein with low affinity for BLAs, called PBP2a, PBP2' or MecA. This response is regulated by the chromosomal mec-divergon, which encodes a signal-transduction system including a transcriptional repressor, MecI, and a sensor/transducer, MecR1, as well as the structural mecA gene. This system is similar to those encoded by bla divergons in S. aureus and Bacillus licheniformis. MecR1 comprises an integral-membrane latent metalloprotease domain facing the cytosol and an extracellular sensor domain. The latter binds BLAs and transmits a signal through the membrane that eventually triggers activation of the metalloprotease moiety, which in turn switches off MecI-induced repression of mecA transcription. The MecR1 sensor domain, MecR1-PBD, reveals a two-domain structure of alpha/beta-type fold reminiscent of penicillin-binding proteins and beta-lactamases, and a catalytic serine residue as the ultimate cause for BLA-binding. Covalent complexes with benzylpenicillin and oxacillin provide evidence that serine acylation does not entail significant structural changes, thus supporting the hypothesis that additional extracellular segments of MecR1 are involved in signal transmission. The chemical nature of the residues shaping the active-site cleft favours stabilisation of the acyl enzyme complexes in MecR1-PBD, in contrast to the closely related OXA beta-lactamases, where the cleft is more likely to promote subsequent hydrolysis. The present structural data provide insights into the mec-encoded BLA-response mechanism and an explanation for kinetic differences in signal transmission with the related bla-encoded systems.
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Affiliation(s)
- Aniebrys Marrero
- Institut de Biologia Molecular de Barcelona, C.I.D.-C.S.I.C. C/Jordi Girona, 18-26 08034 Barcelona, Spain
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34
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Thumanu K, Cha J, Fisher JF, Perrins R, Mobashery S, Wharton C. Discrete steps in sensing of beta-lactam antibiotics by the BlaR1 protein of the methicillin-resistant Staphylococcus aureus bacterium. Proc Natl Acad Sci U S A 2006; 103:10630-5. [PMID: 16815972 PMCID: PMC1502283 DOI: 10.1073/pnas.0601971103] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Chemical sensing by cell-surface receptors to effect signal transduction is a ubiquitous biological event. Despite extensive structural biochemical study, detailed knowledge of how signal transduction occurs is largely lacking. We report herein a kinetic and structural study, obtained by stopped-flow IR spectroscopy, of the activation of the BlaR1 receptor of the Staphylococcus aureus bacterium by beta-lactam antibiotics. The cell-surface BlaR1 receptor alerts the bacterium to the presence of beta-lactam antibiotics, resulting in expression of the gene for a beta-lactamase enzyme. This enzyme hydrolytically destroys the remaining beta-lactam antibiotics. IR spectroscopic interrogation of the beta-lactam-BlaR1 receptor reaction has allowed the simultaneous measurement of the chemical events of receptor recognition of the beta-lactam and the characterization of the conformational changes in the BlaR1 receptor that result. The key chemical events in beta-lactam recognition are serine acylation and subsequent irreversible decarboxylation of the BlaR1 active site lysine carbamate. Both events are observed by stopped-flow IR kinetics and (13)C isotope-edited IR spectroscopy. The secondary structural changes in the BlaR1 receptor conformation that occur as a consequence of this acylation/decarboxylation are predicted to correlate to the signal transduction event accomplished by this receptor.
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Affiliation(s)
- Kanjana Thumanu
- *School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom; and
| | - Jooyoung Cha
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556
| | - Jed F. Fisher
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556
| | - Richard Perrins
- *School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom; and
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556
- To whom correspondence may be addressed. E-mail:
or
| | - Christopher Wharton
- *School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom; and
- To whom correspondence may be addressed. E-mail:
or
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35
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Minetti CASA, Remeta DP. Energetics of membrane protein folding and stability. Arch Biochem Biophys 2006; 453:32-53. [PMID: 16712771 DOI: 10.1016/j.abb.2006.03.023] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Accepted: 03/23/2006] [Indexed: 11/24/2022]
Abstract
The critical role of membrane proteins in a myriad of biological and physiological functions has spawned numerous investigations over the past several decades with the long-term goal of identifying the molecular origins and energetic forces that stabilize these proteins within the membrane. Parallel structural and thermodynamics studies on several systems have provided significant insight regarding the driving forces governing folding, assembly, insertion, and translocation of membrane proteins. The present review surveys families of membrane-associated proteins including alpha-helical and beta-barrel structures, viral surface receptors, and pore-forming toxins, citing representative proteins within each of these classes for further scrutiny in terms of structure-function relationships and global conformational stability. This overview presents seminal findings from pioneering studies on the energetics of membrane protein folding and stability to modern techniques that are exploiting the use of molecular genetics and single molecule studies. An overall consensus regarding the molecular origins of membrane protein stability is that a number of intrinsic properties resemble features of soluble proteins, yet there are distinct energetic differences arising from specific intra- and intermolecular interactions within the membrane. The combined efforts from structural, energetics, and dynamics approaches offer unique insights and improve our fundamental understanding of the driving forces dictating membrane protein folding and stability.
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Affiliation(s)
- Conceição A S A Minetti
- Rutgers-The State University of New Jersey, Department of Chemistry and Chemical Biology, Piscataway, NJ 08854, USA.
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36
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Safo MK, Ko TP, Musayev FN, Zhao Q, Wang AHJ, Archer GL. Structure of the MecI repressor from Staphylococcus aureus in complex with the cognate DNA operator of mec. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:320-4. [PMID: 16582476 PMCID: PMC2222568 DOI: 10.1107/s1744309106009742] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Accepted: 03/15/2006] [Indexed: 11/10/2022]
Abstract
The dimeric repressor MecI regulates the mecA gene that encodes the penicillin-binding protein PBP-2a in methicillin-resistant Staphylococcus aureus (MRSA). MecI is similar to BlaI, the repressor for the blaZ gene of beta-lactamase. MecI and BlaI can bind to both operator DNA sequences. The crystal structure of MecI in complex with the 32 base-pair cognate DNA of mec was determined to 3.8 A resolution. MecI is a homodimer and each monomer consists of a compact N-terminal winged-helix domain, which binds to DNA, and a loosely packed C-terminal helical domain, which intertwines with its counter-monomer. The crystal contains horizontal layers of virtual DNA double helices extending in three directions, which are separated by perpendicular DNA segments. Each DNA segment is bound to two MecI dimers. Similar to the BlaI-mec complex, but unlike the MecI-bla complex, the MecI repressors bind to both sides of the mec DNA dyad that contains four conserved sequences of TACA/TGTA. The results confirm the up-and-down binding to the mec operator, which may account for cooperative effect of the repressor.
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Affiliation(s)
- Martin K Safo
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, Virginia 23298, USA.
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37
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Wilke MS, Lovering AL, Strynadka NCJ. Beta-lactam antibiotic resistance: a current structural perspective. Curr Opin Microbiol 2006; 8:525-33. [PMID: 16129657 DOI: 10.1016/j.mib.2005.08.016] [Citation(s) in RCA: 230] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2005] [Accepted: 08/17/2005] [Indexed: 10/25/2022]
Abstract
Bacterial resistance to beta-lactam antibiotics can be achieved by any of three strategies: the production of beta-lactam-hydrolyzing beta-lactamase enzymes, the utilization of beta-lactam-insensitive cell wall transpeptidases, and the active expulsion of beta-lactam molecules from Gram-negative cells by way of efflux pumps. In recent years, structural biology has contributed significantly to the understanding of these processes and should prove invaluable in the design of drugs to combat beta-lactam resistance in the future.
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Affiliation(s)
- Mark S Wilke
- Department of Biochemistry and Molecular Biology, and the Center for Blood Research, University of British Columbia, 2146 Health Sciences Mall, Vancouver, BC, Canada V6T 1Z3
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38
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Fisher JF, Meroueh SO, Mobashery S. Bacterial resistance to beta-lactam antibiotics: compelling opportunism, compelling opportunity. Chem Rev 2005; 105:395-424. [PMID: 15700950 DOI: 10.1021/cr030102i] [Citation(s) in RCA: 684] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Jed F Fisher
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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39
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Wilke MS, Hills TL, Zhang HZ, Chambers HF, Strynadka NCJ. Crystal Structures of the Apo and Penicillin-acylated Forms of the BlaR1 β-Lactam Sensor of Staphylococcus aureus. J Biol Chem 2004; 279:47278-87. [PMID: 15322076 DOI: 10.1074/jbc.m407054200] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Staphylococcus aureus is among the most prevalent and antibiotic-resistant of pathogenic bacteria. The resistance of S. aureus to prototypal beta-lactam antibiotics is conferred by two mechanisms: (i) secretion of hydrolytic beta-lactamase enzymes and (ii) production of beta-lactam-insensitive penicillin-binding proteins (PBP2a). Despite their distinct modes of resistance, expression of these proteins is controlled by similar regulation systems, including a repressor (BlaI/MecI) and a multidomain transmembrane receptor (BlaR1/MecR1). Resistance is triggered in response to a covalent binding event between a beta-lactam antibiotic and the extracellular sensor domain of BlaR1/MecR1 by transduction of the binding signal to an intracellular protease domain capable of repressor inactivation. This study describes the first crystal structures of the sensor domain of BlaR1 (BlaRS) from S. aureus in both the apo and penicillin-acylated forms. The structures show that the sensor domain resembles the beta-lactam-hydrolyzing class D beta-lactamases, but is rendered a penicillin-binding protein due to the formation of a very stable acyl-enzyme. Surprisingly, conformational changes upon penicillin binding were not observed in our structures, supporting the hypothesis that transduction of the antibiotic-binding signal into the cytosol is mediated by additional intramolecular interactions of the sensor domain with an adjacent extracellular loop in BlaR1.
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Affiliation(s)
- Mark S Wilke
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
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40
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Birck C, Cha JY, Cross J, Schulze-Briese C, Meroueh SO, Schlegel HB, Mobashery S, Samama JP. X-ray Crystal Structure of the Acylated β-Lactam Sensor Domain of BlaR1 from Staphylococcus aureus and the Mechanism of Receptor Activation for Signal Transduction. J Am Chem Soc 2004; 126:13945-7. [PMID: 15506754 DOI: 10.1021/ja044742u] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Methicillin-resistant strains of Staphylococcus aureus (MRSA) are the major cause of infections worldwide. Transcription of the beta-lactamase and PBP2a resistance genes is mediated by two closely related signal-transducing integral membrane proteins, BlaR1 and MecR1, upon binding of the beta-lactam inducer to the sensor domain. Herein we report the crystal structure at 1.75 A resolution of the sensor domain of BlaR1 in complex with a cephalosporin antibiotic. Activation of the signal transducer involves acylation of serine 389 by the beta-lactam antibiotic, a process promoted by the N-carboxylated side chain of Lys392. We present evidence that, on acylation, the lysine side chain experiences a spontaneous decarboxylation that entraps the sensor in its activated state. Kinetic determinations and quantum mechanical/molecular mechanical calculations and the interaction networks in the crystal structure shed light on how this unprecedented process for activation of a receptor may be achieved and provide insights into the mechanistic features that differentiate the signal-transducing receptor from the structurally related class D beta-lactamases, enzymes of antibiotic resistance.
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Affiliation(s)
- Catherine Birck
- Département de Génomique et Biologie Structurales, IGBMC CNRS/INSERM/ULP, 1 rue Laurent Fries, BP 10142, 67404 - Illkirch CU Strasbourg, France
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41
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MallorquÃ-Fernández G, Marrero A, GarcÃa-Piquè S, GarcÃa-Castellanos R, Gomis-Rüth F. Staphylococcal methicillin resistance: fine focus on folds and functions. FEMS Microbiol Lett 2004. [DOI: 10.1111/j.1574-6968.2004.tb09560.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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42
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Hanique S, Colombo ML, Goormaghtigh E, Soumillion P, Frère JM, Joris B. Evidence of an Intramolecular Interaction between the Two Domains of the BlaR1 Penicillin Receptor during the Signal Transduction. J Biol Chem 2004; 279:14264-72. [PMID: 14736870 DOI: 10.1074/jbc.m313488200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The BlaR1 protein is a penicillin-sensory transducer involved in the induction of the Bacillus licheniformis beta-lactamase. The amino-terminal domain of the protein exhibits four transmembrane segments (TM1-TM4) that form a four-alpha-helix bundle embedded in the plasma bilayer. The carboxyl-terminal domain of 250 amino acids (BlaR-CTD) fused at the carboxyl end of TM4 possesses the amino acid sequence signature of penicillin-binding proteins. This membrane topology suggests that BlaR-CTD and the BlaR-amino-terminal domain are responsible for signal reception and signal transduction, respectively. With the use of phage display experiments, we highlight herein an interaction between BlaR-CTD and the extracellular, 63-amino acid L2 loop connecting TM2 and TM3. This interaction does not occur in the presence of penicillin. This result suggests that binding of the antibiotic to BlaR1 might entail the release of the interaction between L2 and BlaR-CTD, causing a motion of the alpha-helix bundle and transfer of the information to the cytoplasm of the cell. In addition, fluorescence spectroscopy, CD, and Fourier transform IR spectroscopy experiments indicate that in contrast to the behavior of the corresponding Staphylococcus aureus protein, the beta-lactam antibiotic does not induce a drastic conformational change in B. licheniformis BlaR-CTD.
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Affiliation(s)
- Sophie Hanique
- Centre d'Ingénierie des Protéines, Institut de Chimie, Université de Liège, B-4000 Sart-Tilman, Belgium
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Colombo ML, Hanique S, Baurin SL, Bauvois C, De Vriendt K, Van Beeumen JJ, Frère JM, Joris B. The ybxI gene of Bacillus subtilis 168 encodes a class D beta-lactamase of low activity. Antimicrob Agents Chemother 2004; 48:484-90. [PMID: 14742199 PMCID: PMC321513 DOI: 10.1128/aac.48.2.484-490.2004] [Citation(s) in RCA: 12] [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
The ybxI gene of Bacillus subtilis 168 encodes a preprotein of 267 amino acid residues, including a putative signal peptide of 23 residues. The YbxI primary structure exhibits high similarity scores with two members of the superfamily of the serine penicillin-recognizing enzymes: the class D beta-lactamases and the hydrophilic carboxy-terminal domains of the BlaR and MecR penicillin receptors. To determine the function and the activity of this putative penicillin-recognizing enzyme, we have subcloned the ybxI gene in the pET-26b expression vector. Transformation of Escherichia coli BL21(DE3) by the recombinant plasmid pCIP51 resulted in the export of the mature YbxI in the periplasm as a water-soluble protein. The recombinant protein was purified to 95% homogeneity. YbxI interacts with several beta-lactam antibiotics and can hydrolyze some of them. YbxI is not inactivated by clavulanic acid. The YbxI function and its enzymatic activity in B. subtilis remain unknown. The acyl-enzyme obtained after incubation of YbxI with a fluorescent derivative of ampicillin can be detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, confirming that YbxI can be acylated by beta-lactam antibiotics. YbxI does not hydrolyze some of the standard substrates of D-alanyl-D-alanine peptidases, the targets of penicillin. YbxI belongs to the penicillin-recognizing enzyme family but has an activity intermediate between those of a penicillin-binding protein and a beta-lactamase.
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Affiliation(s)
- Maria-Luigi Colombo
- Centre d'Ingénierie des Protéines, Institut de Chimie B6a, Université de Liège, Sart Tilman, B-4000 Liège 1, Belgium
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