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Barceló IM, Jordana-Lluch E, Escobar-Salom M, Torrens G, Fraile-Ribot PA, Cabot G, Mulet X, Zamorano L, Juan C, Oliver A. Role of Enzymatic Activity in the Biological Cost Associated with the Production of AmpC β-Lactamases in Pseudomonas aeruginosa. Microbiol Spectr 2022; 10:e0270022. [PMID: 36214681 PMCID: PMC9604156 DOI: 10.1128/spectrum.02700-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/22/2022] [Indexed: 01/04/2023] Open
Abstract
In the current scenario of growing antibiotic resistance, understanding the interplay between resistance mechanisms and biological costs is crucial for designing therapeutic strategies. In this regard, intrinsic AmpC β-lactamase hyperproduction is probably the most important resistance mechanism of Pseudomonas aeruginosa, proven to entail important biological burdens that attenuate virulence mostly under peptidoglycan recycling alterations. P. aeruginosa can acquire resistance to new β-lactam-β-lactamase inhibitor combinations (ceftazidime-avibactam and ceftolozane-tazobactam) through mutations affecting ampC and its regulatory genes, but the impact of these mutations on the associated biological cost and the role that β-lactamase activity plays per se in contributing to the above-mentioned virulence attenuation are unknown. The same questions remain unsolved for plasmid-encoded AmpC-type β-lactamases such as FOX enzymes, some of which also provide resistance to new β-lactam-β-lactamase inhibitor combinations. Here, we assessed from different perspectives the effects of changes in the active center and, thus, in the hydrolytic spectrum resistance to inhibitors of AmpC-type β-lactamases on the fitness and virulence of P. aeruginosa, using site-directed mutagenesis; the previously described AmpC variants T96I, G183D, and ΔG229-E247; and, finally, blaFOX-4 versus blaFOX-8. Our results indicate the essential role of AmpC activity per se in causing the reported full virulence attenuation (in terms of growth, motility, cytotoxicity, and Galleria mellonella larvae killing), although the biological cost of the above-mentioned AmpC-type variants was similar to that of the wild-type enzymes. This suggests that there is not an important biological burden that may limit the selection/spread of these variants, which could progressively compromise the future effectiveness of the above-mentioned drug combinations. IMPORTANCE The growing antibiotic resistance of the top nosocomial pathogen Pseudomonas aeruginosa pushes research to explore new therapeutic strategies, for which the resistance-versus-virulence balance is a promising source of targets. While resistance often entails significant biological costs, little is known about the bases of the virulence attenuations associated with a resistance mechanism as extraordinarily relevant as β-lactamase production. We demonstrate that besides potential energy and cell wall alterations, the enzymatic activity of the P. aeruginosa cephalosporinase AmpC is essential for causing the full attenuation associated with its hyperproduction by affecting different features related to pathogenesis, a fact exploitable from the antivirulence perspective. Less encouraging, we also show that the production of different chromosomal/plasmid-encoded AmpC derivatives conferring resistance to some of the newest antibiotic combinations causes no significantly increased biological burdens, which suggests a free way for the selection/spread of these types of variants, potentially compromising the future effectiveness of these antipseudomonal therapies.
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Affiliation(s)
- Isabel M. Barceló
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Elena Jordana-Lluch
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
| | - María Escobar-Salom
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Gabriel Torrens
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
- Department of Molecular Biology, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
- Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden
| | - Pablo A. Fraile-Ribot
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Gabriel Cabot
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Xavier Mulet
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Laura Zamorano
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Carlos Juan
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
| | - Antonio Oliver
- Research Unit, University Hospital Son Espases-Health Research Institute of the Balearic Islands (IdISBa), Palma, Spain
- Microbiology Department, University Hospital Son Espases, Palma, Spain
- Centro de Investigación Biomédica en Red, Enfermedades Infecciosas, Madrid, Spain
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Brem J, Panduwawala T, Hansen JU, Hewitt J, Liepins E, Donets P, Espina L, Farley AJM, Shubin K, Campillos GG, Kiuru P, Shishodia S, Krahn D, Leśniak RK, Schmidt Adrian J, Calvopiña K, Turrientes MC, Kavanagh ME, Lubriks D, Hinchliffe P, Langley GW, Aboklaish AF, Eneroth A, Backlund M, Baran AG, Nielsen EI, Speake M, Kuka J, Robinson J, Grinberga S, Robinson L, McDonough MA, Rydzik AM, Leissing TM, Jimenez-Castellanos JC, Avison MB, Da Silva Pinto S, Pannifer AD, Martjuga M, Widlake E, Priede M, Hopkins Navratilova I, Gniadkowski M, Belfrage AK, Brandt P, Yli-Kauhaluoma J, Bacque E, Page MGP, Björkling F, Tyrrell JM, Spencer J, Lang PA, Baranczewski P, Cantón R, McElroy SP, Jones PS, Baquero F, Suna E, Morrison A, Walsh TR, Schofield CJ. Imitation of β-lactam binding enables broad-spectrum metallo-β-lactamase inhibitors. Nat Chem 2022; 14:15-24. [PMID: 34903857 DOI: 10.1038/s41557-021-00831-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 09/30/2021] [Indexed: 11/08/2022]
Abstract
Carbapenems are vital antibiotics, but their efficacy is increasingly compromised by metallo-β-lactamases (MBLs). Here we report the discovery and optimization of potent broad-spectrum MBL inhibitors. A high-throughput screen for NDM-1 inhibitors identified indole-2-carboxylates (InCs) as potential β-lactamase stable β-lactam mimics. Subsequent structure-activity relationship studies revealed InCs as a new class of potent MBL inhibitor, active against all MBL classes of major clinical relevance. Crystallographic studies revealed a binding mode of the InCs to MBLs that, in some regards, mimics that predicted for intact carbapenems, including with respect to maintenance of the Zn(II)-bound hydroxyl, and in other regards mimics binding observed in MBL-carbapenem product complexes. InCs restore carbapenem activity against multiple drug-resistant Gram-negative bacteria and have a low frequency of resistance. InCs also have a good in vivo safety profile, and when combined with meropenem show a strong in vivo efficacy in peritonitis and thigh mouse infection models.
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Affiliation(s)
- Jürgen Brem
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK.
| | - Tharindi Panduwawala
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | | | - Joanne Hewitt
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
| | | | - Pawel Donets
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | - Laura Espina
- Department of Medical Microbiology, Institute of infection & Immunity, Cardiff University, Cardiff, UK
| | - Alistair J M Farley
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Kirill Shubin
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | - Gonzalo Gomez Campillos
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Paula Kiuru
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Shifali Shishodia
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Daniel Krahn
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Robert K Leśniak
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Juliane Schmidt Adrian
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Karina Calvopiña
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - María-Carmen Turrientes
- Department of Microbiology, Ramón y Cajal University Hospital and Ramón y Cajal Institute for Health Research (IRYCIS), Madrid, Spain
| | - Madeline E Kavanagh
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | | | - Philip Hinchliffe
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Gareth W Langley
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
- Charles River Laboratories, Saffron Walden, UK
| | - Ali F Aboklaish
- Department of Medical Microbiology, Institute of infection & Immunity, Cardiff University, Cardiff, UK
| | - Anders Eneroth
- Department of Pharmacy, Uppsala Drug Optimization and Pharmaceutical Profiling Platform (UDOPP), Uppsala University, Uppsala, Sweden
| | - Maria Backlund
- Department of Pharmacy, Uppsala Drug Optimization and Pharmaceutical Profiling Platform (UDOPP), Uppsala University, Uppsala, Sweden
| | | | | | - Michael Speake
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
- BioAscent Discovery Ltd, Newhouse, UK
| | - Janis Kuka
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | - John Robinson
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
- BioAscent Discovery Ltd, Newhouse, UK
| | | | - Lindsay Robinson
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
- BioAscent Discovery Ltd, Newhouse, UK
| | - Michael A McDonough
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Anna M Rydzik
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
- Research and Early Development, Respiratory & Immunology, AstraZeneca, Mölndal, Sweden
| | - Thomas M Leissing
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Juan Carlos Jimenez-Castellanos
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
- Chemical Biology of Antibiotics, Centre for Infection & Immunity (CIIL), Pasteur Institute, INSERM U1019 - CNRS UMR 9017, Lille, France
| | - Matthew B Avison
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Solange Da Silva Pinto
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Andrew D Pannifer
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
| | | | - Emma Widlake
- Department of Medical Microbiology, Institute of infection & Immunity, Cardiff University, Cardiff, UK
| | | | | | - Marek Gniadkowski
- Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland
| | - Anna Karin Belfrage
- Department of Medicinal Chemistry, Drug Design and Discovery, Uppsala University, Uppsala, Sweden
| | - Peter Brandt
- Department of Medicinal Chemistry, Drug Design and Discovery, Uppsala University, Uppsala, Sweden
- Beactica Therapeutics AB, Uppsala, Sweden
| | - Jari Yli-Kauhaluoma
- Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Eric Bacque
- Evotec Infectious Diseases Lyon, Marcy l'Etoile, France
| | | | - Fredrik Björkling
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Jonathan M Tyrrell
- Department of Medical Microbiology, Institute of infection & Immunity, Cardiff University, Cardiff, UK
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - James Spencer
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Pauline A Lang
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK
| | - Pawel Baranczewski
- Department of Pharmacy, SciLifeLab Drug Discovery and Development Platform, ADME of Therapeutics Facility, Uppsala University, Uppsala, Sweden
| | - Rafael Cantón
- Department of Microbiology, Ramón y Cajal University Hospital and Ramón y Cajal Institute for Health Research (IRYCIS), Madrid, Spain
| | - Stuart P McElroy
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
- BioAscent Discovery Ltd, Newhouse, UK
| | - Philip S Jones
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
- BioAscent Discovery Ltd, Newhouse, UK
| | - Fernando Baquero
- Department of Microbiology, Ramón y Cajal University Hospital and Ramón y Cajal Institute for Health Research (IRYCIS), Madrid, Spain
| | - Edgars Suna
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | - Angus Morrison
- University of Dundee, European Screening Centre, BioCity Scotland, Newhouse, UK
- BioAscent Discovery Ltd, Newhouse, UK
| | - Timothy R Walsh
- Department of Medical Microbiology, Institute of infection & Immunity, Cardiff University, Cardiff, UK
| | - Christopher J Schofield
- Department of Chemistry, Chemistry Research Laboratory and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, UK.
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Lucic A, Hinchliffe P, Malla TR, Tooke CL, Brem J, Calvopiña K, Lohans CT, Rabe P, McDonough MA, Armistead T, Orville AM, Spencer J, Schofield CJ. Faropenem reacts with serine and metallo-β-lactamases to give multiple products. Eur J Med Chem 2021; 215:113257. [PMID: 33618159 PMCID: PMC7614720 DOI: 10.1016/j.ejmech.2021.113257] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/23/2021] [Accepted: 01/30/2021] [Indexed: 11/30/2022]
Abstract
Penems have demonstrated potential as antibacterials and β-lactamase inhibitors; however, their clinical use has been limited, especially in comparison with the structurally related carbapenems. Faropenem is an orally active antibiotic with a C-2 tetrahydrofuran (THF) ring, which is resistant to hydrolysis by some β-lactamases. We report studies on the reactions of faropenem with carbapenem-hydrolysing β-lactamases, focusing on the class A serine β-lactamase KPC-2 and the metallo β-lactamases (MBLs) VIM-2 (a subclass B1 MBL) and L1 (a B3 MBL). Kinetic studies show that faropenem is a substrate for all three β-lactamases, though it is less efficiently hydrolysed by KPC-2. Crystallographic analyses on faropenem-derived complexes reveal opening of the β-lactam ring with formation of an imine with KPC-2, VIM-2, and L1. In the cases of the KPC-2 and VIM-2 structures, the THF ring is opened to give an alkene, but with L1 the THF ring remains intact. Solution state studies, employing NMR, were performed on L1, KPC-2, VIM-2, VIM-1, NDM-1, OXA-23, OXA-10, and OXA-48. The solution results reveal, in all cases, formation of imine products in which the THF ring is opened; formation of a THF ring-closed imine product was only observed with VIM-1 and VIM-2. An enamine product with a closed THF ring was also observed in all cases, at varying levels. Combined with previous reports, the results exemplify the potential for different outcomes in the reactions of penems with MBLs and SBLs and imply further structure-activity relationship studies are worthwhile to optimise the interactions of penems with β-lactamases. They also exemplify how crystal structures of β-lactamase substrate/inhibitor complexes do not always reflect reaction outcomes in solution.
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Affiliation(s)
- Anka Lucic
- Chemistry Research Laboratory, The Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Philip Hinchliffe
- Cellular and Molecular Medicine, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom
| | - Tika R Malla
- Chemistry Research Laboratory, The Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Catherine L Tooke
- Cellular and Molecular Medicine, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom
| | - Jürgen Brem
- Chemistry Research Laboratory, The Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Karina Calvopiña
- Chemistry Research Laboratory, The Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | | | - Patrick Rabe
- Chemistry Research Laboratory, The Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Michael A McDonough
- Chemistry Research Laboratory, The Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom
| | - Timothy Armistead
- Cellular and Molecular Medicine, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom
| | - Allen M Orville
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, United Kingdom.
| | - James Spencer
- Cellular and Molecular Medicine, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, United Kingdom.
| | - Christopher J Schofield
- Chemistry Research Laboratory, The Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom.
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Pira A, Scorciapino MA, Bodrenko IV, Bosin A, Acosta-Gutiérrez S, Ceccarelli M. Permeation of β-Lactamase Inhibitors through the General Porins of Gram-Negative Bacteria. Molecules 2020; 25:E5747. [PMID: 33291474 PMCID: PMC7730927 DOI: 10.3390/molecules25235747] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/01/2020] [Accepted: 12/03/2020] [Indexed: 11/16/2022] Open
Abstract
Modern medicine relies upon antibiotics, but we have arrived to the point where our inability to come up with new effective molecules against resistant pathogens, together with the declining private investment, is resulting in the number of untreatable infections increasing worldwide at worrying pace. Among other pathogens, widely recognized institutions have indicated Gram-negative bacteria as particularly challenging, due to the presence of the outer membrane. The very first step in the action of every antibiotic or adjuvant is the permeation through this membrane, with small hydrophilic drugs usually crossing through protein channels. Thus, a detailed understanding of their properties at a molecular level is crucial. By making use of Molecular Dynamics simulations, we compared the two main porins of four members of the Enterobacteriaceae family, and, in this paper, we show their shared geometrical and electrostatic characteristics. Then, we used metadynamics simulations to reconstruct the free energy for permeation of selected diazobicyclooctans through OmpF. We demonstrate how porins features are coupled to those of the translocating species, modulating their passive permeation. In particular, we show that the minimal projection area of a molecule is a better descriptor than its molecular mass or the volume. Together with the magnitude and orientation of the electric dipole moment, these are the crucial parameters to gain an efficient compensation between the entropic and enthalpic contributions to the free energy barrier required for permeation. Our results confirm the possibility to predict the permeability of molecules through porins by using a few molecular parameters and bolster the general model according to which the free energy increase is mostly due to the decrease of conformational entropy, and this can be compensated by a favorable alignment of the electric dipole with respect to the channel intrinsic electric field.
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Affiliation(s)
- Alessandro Pira
- Department of Physics, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (A.P.); (A.B.)
| | - Mariano Andrea Scorciapino
- Department of Chemical and Geological Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy;
| | - Igor V. Bodrenko
- CNR/IOM Sezione di Cagliari, Cittadella Universitaria, 09042 Monserrato, Italy;
| | - Andrea Bosin
- Department of Physics, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (A.P.); (A.B.)
| | | | - Matteo Ceccarelli
- Department of Physics, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (A.P.); (A.B.)
- CNR/IOM Sezione di Cagliari, Cittadella Universitaria, 09042 Monserrato, Italy;
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Mondal AH, Yadav D, Ali A, Khan N, Jin JO, Haq QMR. Anti-Bacterial and Anti-Candidal Activity of Silver Nanoparticles Biosynthesized Using Citrobacter spp. MS5 Culture Supernatant. Biomolecules 2020; 10:E944. [PMID: 32580522 PMCID: PMC7355547 DOI: 10.3390/biom10060944] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/19/2020] [Accepted: 06/19/2020] [Indexed: 01/26/2023] Open
Abstract
The present study described the extracellular synthesis of silver nanoparticles (AgNPs) using environmental bacterial isolate Citrobacter spp. MS5 culture supernatant. To our best knowledge, no previous study reported the biosynthesis of AgNPs using this bacterial isolate. The biosynthesized AgNPs were characterized using different techniques like UV-Vis spectroscopy, fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) equipped with energy dispersive X-ray (EDX). The analysis of UV-Vis spectra revealed absorption maxima at 415 nm due to surface plasmon resonance (SPR) indicated the formation of AgNPs and FTIR spectrum confirmed the participation of proteins molecule in AgNPs synthesis. XRD and EDX spectrum confirmed the metallic and crystalline nature of AgNPs. TEM and SEM showed spherical nanoparticles with a size range of 5-15 nm. The biosynthesized AgNPs showed effective independent as well as enhanced combined antibacterial activity against extended spectrum β-lactamase (ESBL) producing multidrug resistant Gram-negative bacteria. Further, effective antifungal activity of AgNPs was observed towards pathogenic Candida spp. The present study provides evidence for eco-friendly biosynthesis of well-characterized AgNPs and their potential antibacterial as well as antifungal activity.
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Affiliation(s)
- Aftab Hossain Mondal
- Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India; (A.H.M.); (A.A.); (N.K.)
| | - Dhananjay Yadav
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea;
| | - Asghar Ali
- Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India; (A.H.M.); (A.A.); (N.K.)
| | - Neelofar Khan
- Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India; (A.H.M.); (A.A.); (N.K.)
| | - Jun O Jin
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea;
- Research Institute of Cell Culture, Yeungnam University, Gyeongsan 38541, Korea
| | - Qazi Mohd Rizwanul Haq
- Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India; (A.H.M.); (A.A.); (N.K.)
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Tooke CL, Hinchliffe P, Lang PA, Mulholland AJ, Brem J, Schofield CJ, Spencer J. Molecular Basis of Class A β-Lactamase Inhibition by Relebactam. Antimicrob Agents Chemother 2019; 63:AAC.00564-19. [PMID: 31383664 PMCID: PMC6761529 DOI: 10.1128/aac.00564-19] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 07/04/2019] [Indexed: 12/23/2022] Open
Abstract
β-Lactamase production is the major β-lactam resistance mechanism in Gram-negative bacteria. β-Lactamase inhibitors (BLIs) efficacious against serine β-lactamase (SBL) producers, especially strains carrying the widely disseminated class A enzymes, are required. Relebactam, a diazabicyclooctane (DBO) BLI, is in phase 3 clinical trials in combination with imipenem for the treatment of infections by multidrug-resistant Enterobacteriaceae We show that relebactam inhibits five clinically important class A SBLs (despite their differing spectra of activity), representing both chromosomal and plasmid-borne enzymes, i.e., the extended-spectrum β-lactamases L2 (inhibition constant 3 μM) and CTX-M-15 (21 μM) and the carbapenemases KPC-2, -3, and -4 (1 to 5 μM). Against purified class A SBLs, relebactam is an inferior inhibitor compared with the clinically approved DBO avibactam (9- to 120-fold differences in half maximal inhibitory concentration [IC50]). MIC assays indicate relebactam potentiates β-lactam (imipenem) activity against KPC-producing Klebsiella pneumoniae, with similar potency to avibactam (with ceftazidime). Relebactam is less effective than avibactam in combination with aztreonam against Stenotrophomonas maltophilia K279a. X-ray crystal structures of relebactam bound to CTX-M-15, L2, KPC-2, KPC-3, and KPC-4 reveal its C2-linked piperidine ring can sterically clash with Asn104 (CTX-M-15) or His/Trp105 (L2 and KPCs), rationalizing its poorer inhibition activity than that of avibactam, which has a smaller C2 carboxyamide group. Mass spectrometry and crystallographic data show slow, pH-dependent relebactam desulfation by KPC-2, -3, and -4. This comprehensive comparison of relebactam binding across five clinically important class A SBLs will inform the design of future DBOs, with the aim of improving clinical efficacy of BLI-β-lactam combinations.
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Affiliation(s)
- Catherine L Tooke
- School of Cellular and Molecular Medicine, Biomedical Sciences Building, University of Bristol, Bristol, United Kingdom
| | - Philip Hinchliffe
- School of Cellular and Molecular Medicine, Biomedical Sciences Building, University of Bristol, Bristol, United Kingdom
| | - Pauline A Lang
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | - Adrian J Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol, United Kingdom
| | - Jürgen Brem
- Department of Chemistry, University of Oxford, Oxford, United Kingdom
| | | | - James Spencer
- School of Cellular and Molecular Medicine, Biomedical Sciences Building, University of Bristol, Bristol, United Kingdom
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7
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Rodrigues KCS, Costa CLL, Badino AC, Pedrolli DB, Pereira JFB, Cerri MO. Application of Acid and Cold Stresses to Enhance the Production of Clavulanic Acid by Streptomyces clavuligerus. Appl Biochem Biotechnol 2019; 188:706-719. [PMID: 30680701 DOI: 10.1007/s12010-019-02953-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 01/11/2019] [Indexed: 11/26/2022]
Abstract
Clavulanic acid (CA) is frequently prescribed for treatment of bacterial infections. Despite the large number of studies concerning CA production, there is still a need to search for more effective and productive processes because it is mainly produced by biochemical route and is chemically unstable. This paper evaluates the influence of acid and cold stresses on CA production by Streptomyces clavuligerus in bench scale stirred tank bioreactor. Four batch cultures were conducted at constant pH (6.8 or 6.3) and temperature (30, 25, or 20 °C) and five batch cultures were performed with application of acid stress (pH reduction from 6.8 to 6.3), cold stress (reduction from 30 to 20 °C), or both. The highest maximum CA concentration (684.4 mg L-1) was obtained in the culture conducted at constant temperature of 20 °C. However, the culture under acid stress, in which the pH was reduced from 6.8 to 6.3 at a rate of 0.1 pH unit every 6 h, provided the most promising result, exhibiting a global yield coefficient of CA relative to cell formation (YCA/X) of 851.1 mgCA gX-1. High YCA/X values indicate that a small number of cells are able to produce a large amount of antibiotic with formation of smaller amounts of side byproducts. This could be especially attractive for decreasing the complexity and cost of the downstream processing, enhancing CA production.
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Affiliation(s)
- K C S Rodrigues
- Graduate Program of Chemical Engineering, Federal University of São Carlos, C.P. 676, São Carlos, SP, CEP 13565-905, Brazil
| | - C L L Costa
- Graduate Program of Chemical Engineering, Federal University of São Carlos, C.P. 676, São Carlos, SP, CEP 13565-905, Brazil
| | - A C Badino
- Graduate Program of Chemical Engineering, Federal University of São Carlos, C.P. 676, São Carlos, SP, CEP 13565-905, Brazil
| | - D B Pedrolli
- Department of Bioprocesses and Biotechnology, School of Pharmaceutical Sciences, São Paulo State University - UNESP, Araraquara, SP, CEP 14801-902, Brazil
| | - J F B Pereira
- Department of Bioprocesses and Biotechnology, School of Pharmaceutical Sciences, São Paulo State University - UNESP, Araraquara, SP, CEP 14801-902, Brazil
| | - M O Cerri
- Department of Bioprocesses and Biotechnology, School of Pharmaceutical Sciences, São Paulo State University - UNESP, Araraquara, SP, CEP 14801-902, Brazil.
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8
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Cheng Z, Thomas PW, Ju L, Bergstrom A, Mason K, Clayton D, Miller C, Bethel CR, VanPelt J, Tierney DL, Page RC, Bonomo RA, Fast W, Crowder MW. Evolution of New Delhi metallo-β-lactamase (NDM) in the clinic: Effects of NDM mutations on stability, zinc affinity, and mono-zinc activity. J Biol Chem 2018; 293:12606-12618. [PMID: 29909397 PMCID: PMC6093243 DOI: 10.1074/jbc.ra118.003835] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/07/2018] [Indexed: 11/06/2022] Open
Abstract
Infections by carbapenem-resistant Enterobacteriaceae are difficult to manage owing to broad antibiotic resistance profiles and because of the inability of clinically used β-lactamase inhibitors to counter the activity of metallo-β-lactamases often harbored by these pathogens. Of particular importance is New Delhi metallo-β-lactamase (NDM), which requires a di-nuclear zinc ion cluster for catalytic activity. Here, we compare the structures and functions of clinical NDM variants 1-17. The impact of NDM variants on structure is probed by comparing melting temperature and refolding efficiency and also by spectroscopy (UV-visible, 1H NMR, and EPR) of di-cobalt metalloforms. The impact of NDM variants on function is probed by determining the minimum inhibitory concentrations of various antibiotics, pre-steady-state and steady-state kinetics, inhibitor binding, and zinc dependence of resistance and activity. We observed only minor differences among the fully loaded di-zinc enzymes, but most NDM variants had more distinguishable selective advantages in experiments that mimicked zinc scarcity imposed by typical host defenses. Most NDM variants exhibited improved thermostability (up to ∼10 °C increased Tm ) and improved zinc affinity (up to ∼10-fold decreased Kd, Zn2). We also provide first evidence that some NDM variants have evolved the ability to function as mono-zinc enzymes with high catalytic efficiency (NDM-15, ampicillin: kcat/Km = 5 × 106 m-1 s-1). These findings reveal the molecular mechanisms that NDM variants have evolved to overcome the combined selective pressures of β-lactam antibiotics and zinc deprivation.
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Affiliation(s)
- Zishuo Cheng
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056
| | - Pei W Thomas
- the Division of Chemical Biology and Medicinal Chemistry, College of Pharmacy, and the LaMontagne Center of Infectious Disease, University of Texas, Austin, Texas 78712
| | - Lincheng Ju
- the Department of Urology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, China
| | - Alexander Bergstrom
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056
| | - Kelly Mason
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056
| | - Delaney Clayton
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056
| | - Callie Miller
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056
| | - Christopher R Bethel
- the Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, and
| | - Jamie VanPelt
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056
| | - David L Tierney
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056,
| | - Richard C Page
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056,
| | - Robert A Bonomo
- the Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, and
- the Departments of Medicine, Pharmacology, Molecular Biology and Microbiology, Biochemistry, Proteomics, and Bioinformatics, Case Western Reserve University (CWRU)-Cleveland Veterans Administration Medical Center (VAMC) Center of Antimicrobial Resistance and Epidemiology (CARES), Cleveland, Ohio 44106
| | - Walter Fast
- the Division of Chemical Biology and Medicinal Chemistry, College of Pharmacy, and the LaMontagne Center of Infectious Disease, University of Texas, Austin, Texas 78712,
| | - Michael W Crowder
- From the Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056,
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9
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Che T, Rodkey E, Bethel CR, Shanmugam S, Ding Z, Pusztai-Carey M, Nottingham M, Chai W, Buynak JD, Bonomo RA, van den Akker F, Carey PR. Detecting a quasi-stable imine species on the reaction pathway of SHV-1 β-lactamase and 6β-(hydroxymethyl)penicillanic acid sulfone. Biochemistry 2015; 54:734-43. [PMID: 25536850 PMCID: PMC4310624 DOI: 10.1021/bi501197t] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 12/22/2014] [Indexed: 11/30/2022]
Abstract
For the class A β-lactamase SHV-1, the kinetic and mechanistic properties of the clinically used inhibitor sulbactam are compared with the sulbactam analog substituted in its 6β position by a CH2OH group (6β-(hydroxymethyl)penicillanic acid). The 6β substitution improves both in vitro and microbiological inhibitory properties of sulbactam. Base hydrolysis of both compounds was studied by Raman and NMR spectroscopies and showed that lactam ring opening is followed by fragmentation of the dioxothiazolidine ring leading to formation of the iminium ion within 3 min. The iminium ion slowly loses a proton and converts to cis-enamine (which is a β-aminoacrylate) in 1 h for sulbactam and in 4 h for 6β-(hydroxymethyl) sulbactam. Rapid mix-rapid freeze Raman spectroscopy was used to follow the reactions between the two sulfones and SHV-1. Within 23 ms, a 10-fold excess of sulbactam was entirely hydrolyzed to give a cis-enamine product. In contrast, the 6β-(hydroxymethyl) sulbactam formed longer-lived acyl-enzyme intermediates that are a mixture of imine and enamines. Single crystal Raman studies, soaking in and washing out unreacted substrates, revealed stable populations of imine and trans-enamine acyl enzymes. The corresponding X-ray crystallographic data are consonant with the Raman data and also reveal the role played by the 6β-hydroxymethyl group in retarding hydrolysis of the acyl enzymes. The 6β-hydroxymethyl group sterically hinders approach of the water molecule as well as restraining the side chain of E166 that facilitates hydrolysis.
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Affiliation(s)
- Tao Che
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Elizabeth
A. Rodkey
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Christopher R. Bethel
- Research
Service, Louis Stokes Cleveland Veterans
Affairs Medical Center, Cleveland, Ohio 44106, United States
| | - Sivaprakash Shanmugam
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Zhe Ding
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Marianne Pusztai-Carey
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Michael Nottingham
- Department
of Chemistry, Southern Methodist University, Dallas, Texas 75275, United States
| | - Weirui Chai
- Department
of Chemistry, Southern Methodist University, Dallas, Texas 75275, United States
| | - John D. Buynak
- Department
of Chemistry, Southern Methodist University, Dallas, Texas 75275, United States
| | - Robert A. Bonomo
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
- Research
Service, Louis Stokes Cleveland Veterans
Affairs Medical Center, Cleveland, Ohio 44106, United States
| | - Focco van den Akker
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Paul R. Carey
- Department of Biochemistry, Department of Molecular
Biology and Microbiology, Department of Pharmacology, and Department of
Medicine, Case Western Reserve University, Cleveland, Ohio 44106, United States
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10
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Karsisiotis AI, Damblon C, Roberts GCK. Complete ¹H, ¹⁵N, and ¹³C resonance assignments of Bacillus cereus metallo-β-lactamase and its complex with the inhibitor R-thiomandelic acid. Biomol NMR Assign 2014; 8:313-318. [PMID: 23838816 PMCID: PMC4145196 DOI: 10.1007/s12104-013-9507-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 06/29/2013] [Indexed: 06/02/2023]
Abstract
β-Lactamases inactivate β-lactam antibiotics by hydrolysis of their endocyclic β-lactam bond and are a major cause of antibiotic resistance in pathogenic bacteria. The zinc dependent metallo-β-lactamase enzymes are of particular concern since they are located on highly transmissible plasmids and have a broad spectrum of activity against almost all β-lactam antibiotics. We present here essentially complete (>96%) backbone and sidechain sequence-specific NMR resonance assignments for the Bacillus cereus subclass B1 metallo-β-lactamase, BcII, and for its complex with R-thiomandelic acid, a broad spectrum inhibitor of metallo-β-lactamases. These assignments have been used as the basis for determination of the solution structures of the enzyme and its inhibitor complex and can also be used in a rapid screen for other metallo-β-lactamase inhibitors.
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Affiliation(s)
- Andreas Ioannis Karsisiotis
- The Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Lancaster Road, PO Box 138, Leicester, LE1 9HN UK
- The School of Pharmacy and Pharmaceutical Sciences, Biomedical Sciences Research Institute, University of Ulster, Coleraine, BT52 1SA Northern Ireland UK
| | - Christian Damblon
- The Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Lancaster Road, PO Box 138, Leicester, LE1 9HN UK
- Chimie Biologique Structurale, Institut de Chimie, Sart-Tilman (B6c), Université de Liège, 4000 Liège, Belgium
| | - Gordon C. K. Roberts
- The Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Lancaster Road, PO Box 138, Leicester, LE1 9HN UK
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11
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Nurmohamadi M, Pourghassem H. Clavulanic acid production estimation based on color and structural features of Streptomyces clavuligerus bacteria using self-organizing map and genetic algorithm. Comput Methods Programs Biomed 2014; 114:337-348. [PMID: 24666934 DOI: 10.1016/j.cmpb.2014.02.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 01/03/2014] [Accepted: 02/20/2014] [Indexed: 06/03/2023]
Abstract
The utilization of antibiotics produced by Clavulanic acid (CA) is an increasing need in medicine and industry. Usually, the CA is created from the fermentation of Streptomycen Clavuligerus (SC) bacteria. Analysis of visual and morphological features of SC bacteria is an appropriate measure to estimate the growth of CA. In this paper, an automatic and fast CA production level estimation algorithm based on visual and structural features of SC bacteria instead of statistical methods and experimental evaluation by microbiologist is proposed. In this algorithm, structural features such as the number of newborn branches, thickness of hyphal and bacterial density and also color features such as acceptance color levels are extracted from the SC bacteria. Moreover, PH and biomass of the medium provided by microbiologists are considered as specified features. The level of CA production is estimated by using a new application of Self-Organizing Map (SOM), and a hybrid model of genetic algorithm with back propagation network (GA-BPN). The proposed algorithm is evaluated on four carbonic resources including malt, starch, wheat flour and glycerol that had used as different mediums of bacterial growth. Then, the obtained results are compared and evaluated with observation of specialist. Finally, the Relative Error (RE) for the SOM and GA-BPN are achieved 14.97% and 16.63%, respectively.
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Affiliation(s)
- Maryam Nurmohamadi
- Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Isfahan, Iran
| | - Hossein Pourghassem
- Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Isfahan, Iran.
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12
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Timoşca S, Liscă M. [Betalactamase inhibitors]. Rev Med Chir Soc Med Nat Iasi 1982; 86:35-41. [PMID: 25591246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
- S Timoşca
- Institutul de medicină şi farmacie Iaşi
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