151
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Monteferrante CG, Sultan S, Ten Kate MT, Dekker LJM, Sparbier K, Peer M, Kostzrewa M, Luider TM, Goessens WHF, Burgers PC. Evaluation of different pretreatment protocols to detect accurately clinical carbapenemase-producing Enterobacteriaceae by MALDI-TOF. J Antimicrob Chemother 2016; 71:2856-67. [PMID: 27287232 DOI: 10.1093/jac/dkw208] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/04/2016] [Indexed: 01/20/2023] Open
Abstract
OBJECTIVES Carbapenemase-resistant bacteria are increasingly spreading worldwide causing public concern due to their ability to elude antimicrobial treatment. Early identification of these bacteria is therefore of high importance. Here, we describe the development of a simple and robust protocol for the detection of carbapenemase activity in clinical isolates of Enterobacteriaceae, suitable for routine and clinical applications. METHODS The final protocol involves cellular lysis and enzyme extraction from a defined amount of bacterial cells followed by the addition of a benchmark drug (e.g. the carbapenem antibiotic imipenem or ertapenem). Carbapenem inactivation is mediated by enzymatic hydrolysis (cleavage) of the β-lactam common structural motif, which can be detected using MALDI-TOF MS. RESULTS A total of 260 strains were studied (208 carbapenemase producers and 52 non-carbapenemase producers) resulting in 100% sensitivity and 100% specificity for the KPC, NDM and OXA-48-like PCR-confirmed positive isolates using imipenem as benchmark. Differences between the benchmark (indicator) antibiotics imipenem and ertapenem, buffer constituents and sample preparation methods have been investigated. Carbapenemase activity was further characterized by performing specific inhibitor experiments. Intraday and interday reproducibility (coefficient of variation) of the observed hydrolysis results were 15% and 30%, respectively. A comparative study of our extraction method and a recently published method using whole bacterial cells is presented and differences are discussed. CONCLUSIONS Using this method, an existing carbapenemase activity can be directly read from the mass spectrum as a ratio of hydrolysed product and substrate, setting an important step towards routine application in clinical laboratories.
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Affiliation(s)
- Carmine G Monteferrante
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Sadaf Sultan
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Marian T Ten Kate
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Lennard J M Dekker
- Department of Neurology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | | | | | | | - Theo M Luider
- Department of Neurology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Wil H F Goessens
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Peter C Burgers
- Department of Neurology, Erasmus University Medical Center, Rotterdam, The Netherlands TI-COAST, Science Park 904, 1098 XH Amsterdam, The Netherlands
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152
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New Delhi metallo-β-lactamase-1: structure, inhibitors and detection of producers. Future Med Chem 2016; 8:993-1012. [PMID: 27253479 DOI: 10.4155/fmc-2016-0015] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Since its discovery in 2008, New Delhi metallo-β-lactamase-1 (NDM-1)-producing Enterobacteriaceae have disseminated globally, facilitated predominantly by gut colonization and the spread of plasmids carrying the bla NDM-1 gene. With few effective antibiotics against NDM-1 producers, and resistance developing to those which remain, there is an urgent need to develop new treatments. To date, most drug design in this area has been focused on developing an NDM-1 inhibitor and has been aided by the wealth of structural and mechanistic information available from high resolution x-ray crystallography and molecular modeling. This review aims to summarize current knowledge regarding the detection of NDM-1 producers, the mechanism of action of NDM-1 and to highlight recent attempts toward the development of clinically useful inhibitors.
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153
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Lund BA, Christopeit T, Guttormsen Y, Bayer A, Leiros HKS. Screening and Design of Inhibitor Scaffolds for the Antibiotic Resistance Oxacillinase-48 (OXA-48) through Surface Plasmon Resonance Screening. J Med Chem 2016; 59:5542-54. [PMID: 27165692 DOI: 10.1021/acs.jmedchem.6b00660] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The spread of antibiotic resistant bacteria is a global threat that shakes the foundations of modern healthcare. β-Lactamases are enzymes that confer resistance to β-lactam antibiotics in bacteria, and there is a critical need for new inhibitors of these enzymes for combination therapy together with an antibiotic. With this in mind, we have screened a library of 490 fragments to identify starting points for the development of new inhibitors of the class D β-lactamase oxacillinase-48 (OXA-48) through surface plasmon resonance (SPR), dose-rate inhibition assays, and X-ray crystallography. Furthermore, we have uncovered structure-activity relationships and used alternate conformations from a crystallographic structure to grow a fragment into a more potent compound with a KD of 50 μM and an IC50 of 18 μM.
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Affiliation(s)
- Bjarte Aarmo Lund
- The Norwegian Structural Biology Centre (NorStruct), Department of Chemistry, UiT The Arctic University of Norway , 9037 Tromsø, Norway
| | - Tony Christopeit
- The Norwegian Structural Biology Centre (NorStruct), Department of Chemistry, UiT The Arctic University of Norway , 9037 Tromsø, Norway
| | - Yngve Guttormsen
- Department of Chemistry, UiT The Arctic University of Norway , 9037 Tromsø, Norway
| | - Annette Bayer
- Department of Chemistry, UiT The Arctic University of Norway , 9037 Tromsø, Norway
| | - Hanna-Kirsti S Leiros
- The Norwegian Structural Biology Centre (NorStruct), Department of Chemistry, UiT The Arctic University of Norway , 9037 Tromsø, Norway
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154
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Vallejo JA, Martínez-Guitián M, Vázquez-Ucha JC, González-Bello C, Poza M, Buynak JD, Bethel CR, Bonomo RA, Bou G, Beceiro A. LN-1-255, a penicillanic acid sulfone able to inhibit the class D carbapenemase OXA-48. J Antimicrob Chemother 2016; 71:2171-80. [PMID: 27125555 DOI: 10.1093/jac/dkw105] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 03/04/2016] [Indexed: 01/06/2023] Open
Abstract
OBJECTIVES Carbapenemases are the most important mechanism responsible for carbapenem resistance in Enterobacteriaceae. Among carbapenemases, OXA-48 presents unique challenges as it is resistant to β-lactam inhibitors. Here, we test the capacity of the compound LN-1-255, a 6-alkylidene-2'-substituted penicillanic acid sulfone, to inhibit the activity of the carbapenemase OXA-48. METHODS The OXA-48 gene was cloned and expressed in Klebsiella pneumoniae and Escherichia coli in order to obtain MICs in the presence of inhibitors (clavulanic acid, tazobactam and sulbactam) and LN-1-255. OXA-48 was purified and steady-state kinetics was performed with LN-1-255 and tazobactam. The covalent binding mode of LN-1-255 with OXA-48 was studied by docking assays. RESULTS Both OXA-48-producing clinical and transformant strains displayed increased susceptibility to carbapenem antibiotics in the presence of 4 mg/L LN-1-255 (2-32-fold increased susceptibility) and 16 mg/L LN-1-255 (4-64-fold increased susceptibility). Kinetic assays demonstrated that LN-1-255 is able to inhibit OXA-48 with an acylation efficiency (k2/K) of 10 ± 1 × 10(4) M(-1) s(-1) and a slow deacylation rate (koff) of 7 ± 1 × 10(-4) s(-1). IC50 was 3 nM for LN-1-255 and 1.5 μM for tazobactam. Lastly, kcat/kinact was 500-fold lower for LN-1-255 than for tazobactam. CONCLUSIONS In these studies, carbapenem antibiotics used in combination with LN-1-255 are effective against the carbapenemase OXA-48, an important emerging mechanism of antibiotic resistance. This provides an incentive for further investigations to maximize the efficacy of penicillin sulfone inhibition of class D plasmid-carried Enterobacteriaceae carbapenemases.
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Affiliation(s)
- Juan A Vallejo
- Servicio de Microbiología-Instituto de Investigación Biomédica (INIBIC), 15006 A Coruña, Spain
| | - Marta Martínez-Guitián
- Servicio de Microbiología-Instituto de Investigación Biomédica (INIBIC), 15006 A Coruña, Spain
| | - Juan C Vázquez-Ucha
- Servicio de Microbiología-Instituto de Investigación Biomédica (INIBIC), 15006 A Coruña, Spain
| | - Concepción González-Bello
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Margarita Poza
- Servicio de Microbiología-Instituto de Investigación Biomédica (INIBIC), 15006 A Coruña, Spain
| | - John D Buynak
- Department of Chemistry, Southern Methodist University, Dallas, TX 75275, USA
| | - Christopher R Bethel
- Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA
| | - Robert A Bonomo
- Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA Departments of Biochemistry, Molecular Biology and Microbiology, Pharmacology and Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - German Bou
- Servicio de Microbiología-Instituto de Investigación Biomédica (INIBIC), 15006 A Coruña, Spain
| | - Alejandro Beceiro
- Servicio de Microbiología-Instituto de Investigación Biomédica (INIBIC), 15006 A Coruña, Spain
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155
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Shapiro AB. Investigation of β-lactam antibacterial drugs, β-lactamases, and penicillin-binding proteins with fluorescence polarization and anisotropy: a review. Methods Appl Fluoresc 2016; 4:024002. [DOI: 10.1088/2050-6120/4/2/024002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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156
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Perez F, El Chakhtoura NG, Papp-Wallace K, Wilson BM, Bonomo RA. Treatment options for infections caused by carbapenem-resistant Enterobacteriaceae: can we apply "precision medicine" to antimicrobial chemotherapy? Expert Opin Pharmacother 2016; 17:761-81. [PMID: 26799840 PMCID: PMC4970584 DOI: 10.1517/14656566.2016.1145658] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION For the past three decades, carbapenems played a central role in our antibiotic armamentarium, trusted to effectively treat infections caused by drug-resistant bacteria. The utility of this class of antibiotics has been compromised by the emergence of resistance especially among Enterobacteriaceae. AREAS COVERED We review the current mainstays of pharmacotherapy against infections caused by carbapenem-resistant Enterobacteriaceae (CRE) including tigecycline, aminoglycosides, and rediscovered 'old' antibiotics such as fosfomycin and polymyxins, and discuss their efficacy and potential toxicity. We also summarize the contemporary clinical experience treating CRE infections with antibiotic combination therapy. Finally, we discuss ceftazidime/avibactam and imipenem/relebactam, containing a new generation of beta-lactamase inhibitors, which may offer alternatives to treat CRE infections. We critically evaluate the published literature, identify relevant clinical trials and review documents submitted to the United States Food and Drug Administration. EXPERT OPINION Defining the molecular mechanisms of resistance and applying insights about pharmacodynamic and pharmacokinetic properties of antibiotics, in order to maximize the impact of old and new therapeutic approaches should be the new paradigm in treating infections caused by CRE. A concerted effort is needed to carry out high-quality clinical trials that: i) establish the superiority of combination therapy vs. monotherapy; ii) confirm the role of novel beta-lactam/beta-lactamase inhibitor combinations as therapy against KPC- and OXA-48 producing Enterobacteriaceae; and, iii) evaluate new antibiotics active against CRE as they are introduced into the clinic.
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Affiliation(s)
- Federico Perez
- Medicine, Louis Stokes Cleveland Department of Veterans Affairs Medical Center
- Research Services, Louis Stokes Cleveland Department of Veterans Affairs Medical Center
- Department of Medicine, University Hospitals Case Medical Center
| | | | - Krisztina Papp-Wallace
- Research Services, Louis Stokes Cleveland Department of Veterans Affairs Medical Center
- Department of Medicine, University Hospitals Case Medical Center
- Departments of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | | | - Robert A. Bonomo
- Medicine, Louis Stokes Cleveland Department of Veterans Affairs Medical Center
- Research Services, Louis Stokes Cleveland Department of Veterans Affairs Medical Center
- Department of Medicine, University Hospitals Case Medical Center
- Departments of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, Ohio
- VISN-10 Geriatrics Research, Cleveland, Ohio
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157
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King DT, Sobhanifar S, Strynadka NCJ. One ring to rule them all: Current trends in combating bacterial resistance to the β-lactams. Protein Sci 2016; 25:787-803. [PMID: 26813250 DOI: 10.1002/pro.2889] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 01/20/2016] [Accepted: 01/21/2016] [Indexed: 01/27/2023]
Abstract
From humble beginnings of a contaminated petri dish, β-lactam antibiotics have distinguished themselves among some of the most powerful drugs in human history. The devastating effects of antibiotic resistance have nevertheless led to an "arms race" with disquieting prospects. The emergence of multidrug resistant bacteria threatens an ever-dwindling antibiotic arsenal, calling for new discovery, rediscovery, and innovation in β-lactam research. Here the current state of β-lactam antibiotics from a structural perspective was reviewed.
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Affiliation(s)
- Dustin T King
- Department of Biochemistry and Molecular Biology and Center for Blood Research, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z3
| | - Solmaz Sobhanifar
- Department of Biochemistry and Molecular Biology and Center for Blood Research, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z3
| | - Natalie C J Strynadka
- Department of Biochemistry and Molecular Biology and Center for Blood Research, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z3
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158
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Thomson GK, Snyder JW, McElheny CL, Thomson KS, Doi Y. Coproduction of KPC-18 and VIM-1 Carbapenemases by Enterobacter cloacae: Implications for Newer β-Lactam-β-Lactamase Inhibitor Combinations. J Clin Microbiol 2016; 54:791-4. [PMID: 26719440 PMCID: PMC4767958 DOI: 10.1128/jcm.02739-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 12/22/2015] [Indexed: 01/04/2023] Open
Abstract
Enterobacter cloacae strain G6809 with reduced susceptibility to carbapenems was identified from a patient in a long-term acute care hospital in Kentucky. G6809 belonged to sequence type (ST) 88 and carried two carbapenemase genes, bla(KPC-18) and bla(VIM-1). Whole-genome sequencing localized bla(KPC-18) to the chromosome and bla(VIM-1) to a 58-kb plasmid. The strain was highly resistant to ceftazidime-avibactam. Insidious coproduction of metallo-β-lactamase with KPC-type carbapenemase has implications for the use of next-generation β-lactam-β-lactamase inhibitor combinations.
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Affiliation(s)
- Gina K Thomson
- Department of Microbiology, University of Louisville Hospital, Louisville, Kentucky, USA Department of Pathology and Laboratory Medicine, University of Louisville, Louisville, Kentucky, USA
| | - James W Snyder
- Department of Pathology and Laboratory Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Christi L McElheny
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Kenneth S Thomson
- Department of Pathology and Laboratory Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Yohei Doi
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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159
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Wagner S, Sommer R, Hinsberger S, Lu C, Hartmann RW, Empting M, Titz A. Novel Strategies for the Treatment of Pseudomonas aeruginosa Infections. J Med Chem 2016; 59:5929-69. [DOI: 10.1021/acs.jmedchem.5b01698] [Citation(s) in RCA: 176] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Stefanie Wagner
- Chemical
Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
| | - Roman Sommer
- Chemical
Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
| | - Stefan Hinsberger
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Cenbin Lu
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Rolf W. Hartmann
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Martin Empting
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
- Drug
Design and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
| | - Alexander Titz
- Chemical
Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany
- Deutsches Zentrum für Infektionsforschung (DZIF), 30625 Standort Hannover-Braunschweig, Germany
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160
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Cerceo E, Deitelzweig SB, Sherman BM, Amin AN. Multidrug-Resistant Gram-Negative Bacterial Infections in the Hospital Setting: Overview, Implications for Clinical Practice, and Emerging Treatment Options. Microb Drug Resist 2016; 22:412-31. [PMID: 26866778 DOI: 10.1089/mdr.2015.0220] [Citation(s) in RCA: 160] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The increasing prevalence of infections due to multidrug-resistant (MDR) gram-negative bacteria constitutes a serious threat to global public health due to the limited treatment options available and the historically slow pace of development of new antimicrobial agents. Infections due to MDR strains are associated with increased morbidity and mortality and prolonged hospitalization, which translates to a significant burden on healthcare systems. In particular, MDR strains of Enterobacteriaceae (especially Klebsiella pneumoniae and Escherichia coli), Pseudomonas aeruginosa, and Acinetobacter baumannii have emerged as particularly serious concerns. In the United States, MDR strains of these organisms have been reported from hospitals throughout the country and are not limited to a small subset of hospitals. Factors that have contributed to the persistence and spread of MDR gram-negative bacteria include the following: overuse of existing antimicrobial agents, which has led to the development of adaptive resistance mechanisms by bacteria; a lack of good antimicrobial stewardship such that use of multiple broad-spectrum agents has helped perpetuate the cycle of increasing resistance; and a lack of good infection control practices. The rising prevalence of infections due to MDR gram-negative bacteria presents a significant dilemma in selecting empiric antimicrobial therapy in seriously ill hospitalized patients. A prudent initial strategy is to initiate treatment with a broad-spectrum regimen pending the availability of microbiological results allowing for targeted or narrowing of therapy. Empiric therapy with newer agents that exhibit good activity against MDR gram-negative bacterial strains such as tigecycline, ceftolozane-tazobactam, ceftazidime-avibactam, and others in the development pipeline offer promising alternatives to existing agents.
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Affiliation(s)
- Elizabeth Cerceo
- 1 Division of Hospital Medicine, Cooper Medical School of Rowan University , Camden, New Jersey
| | - Steven B Deitelzweig
- 2 Department of Hospital Medicine, Ochsner Clinical School, Ochsner Health Center , New Orleans, Louisiana
| | | | - Alpesh N Amin
- 4 Department of Medicine, University of California , Irvine, California
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161
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The Chemical Biology of Human Metallo-β-Lactamase Fold Proteins. Trends Biochem Sci 2016; 41:338-355. [PMID: 26805042 PMCID: PMC4819959 DOI: 10.1016/j.tibs.2015.12.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 12/19/2015] [Accepted: 12/22/2015] [Indexed: 01/30/2023]
Abstract
The αββα metallo β-lactamase (MBL) fold (MBLf) was first observed in bacterial enzymes that catalyze the hydrolysis of almost all β-lactam antibiotics, but is now known to be widely distributed. The MBL core protein fold is present in human enzymes with diverse biological roles, including cell detoxification pathways and enabling resistance to clinically important anticancer medicines. Human (h)MBLf enzymes can bind metals, including zinc and iron ions, and catalyze a range of chemically interesting reactions, including both redox (e.g., ETHE1) and hydrolytic processes (e.g., Glyoxalase II, SNM1 nucleases, and CPSF73). With a view to promoting basic research on MBLf enzymes and their medicinal targeting, here we summarize current knowledge of the mechanisms and roles of these important molecules. MBLs are mono- or di-zinc ion-dependent hydrolases that enable bacterial resistance to almost all β-lactam antibiotics. The αββα MBL core fold is widely distributed and supports a range of catalytic activities, including redox reactions. hMBL proteins are a small family of approximately 18 zinc- and iron-dependent proteins with roles in metabolism and/or detoxification and nucleic acid modification. In a notable parallel with the role of bacterial MBLs in antibiotic resistance, some hMBLf enzymes enable resistance to chemotherapy drugs, such as cisplatin and mitomycin C.
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162
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Betts JW, Phee LM, Abdul Momin MHF, Umland KD, Brem J, Schofield CJ, Wareham DW. In vitro and in vivo activity of ML302F: a thioenolate inhibitor of VIM-subfamily metallo β-lactamases. MEDCHEMCOMM 2016. [DOI: 10.1039/c5md00380f] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The thioenol ML302F, recently identified as an inhibitor of class B metallo-β-lactamases (MBLs), restores antibiotic susceptibility to meropenem resistant strains in cells and the Galleria mellonella invertebrate model.
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Affiliation(s)
- Jonathan W. Betts
- Antimicrobial Research Group
- Barts & The London School of Medicine and Dentistry
- Queen Mary University of London
- London
- UK
| | - Lynette M. Phee
- Antimicrobial Research Group
- Barts & The London School of Medicine and Dentistry
- Queen Mary University of London
- London
- UK
| | - Muhd H. F. Abdul Momin
- Antimicrobial Research Group
- Barts & The London School of Medicine and Dentistry
- Queen Mary University of London
- London
- UK
| | | | - Jurgen Brem
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | | | - David W. Wareham
- Antimicrobial Research Group
- Barts & The London School of Medicine and Dentistry
- Queen Mary University of London
- London
- UK
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163
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Abstract
The practice of medicine was profoundly transformed by the introduction of the antibiotics (compounds isolated from Nature) and the antibacterials (compounds prepared by synthesis) for the control of bacterial infection. As a result of the extraordinary success of these compounds over decades of time, a timeless biological activity for these compounds has been presumed. This presumption is no longer. The inexorable acquisition of resistance mechanisms by bacteria is retransforming medical practice. Credible answers to this dilemma are far better recognized than they are being implemented. In this perspective we examine (and in key respects, reiterate) the chemical and biological strategies being used to address the challenge of bacterial resistance.
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Affiliation(s)
- Jed F. Fisher
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame IN 46556–5670, USA
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame IN 46556–5670, USA
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164
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Rajamäki SHM, De Luca L, Capitta F, Porcheddu A. A telescopic one-pot synthesis of β-lactam rings using amines as a convenient source of imines. RSC Adv 2016. [DOI: 10.1039/c6ra02744j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A facile synthetic approach to substituted β-lactams was designed, using secondary benzylic amines and acid chlorides as starting materials. The reactions proceeded smoothly and all the products were obtained in good yields.
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Affiliation(s)
- Suvi H. M. Rajamäki
- Università degli Studi di Sassari
- Dipartimento di Chimica e Farmacia
- Sassari
- Italy
| | - Lidia De Luca
- Università degli Studi di Sassari
- Dipartimento di Chimica e Farmacia
- Sassari
- Italy
| | - Francesca Capitta
- Università degli Studi di Sassari
- Dipartimento di Chimica e Farmacia
- Sassari
- Italy
| | - Andrea Porcheddu
- Università degli Studi di Cagliari
- Dipartimento di Scienze Chimiche e Geologiche
- Cittadella Universitaria
- 09042 Monserrato
- Italy
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165
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Chiem K, Jani S, Fuentes B, Lin DL, Rasche ME, Tolmasky ME. Identification of an Inhibitor of the Aminoglycoside 6'- N-Acetyltransferase type Ib [AAC(6')-Ib] by Glide Molecular Docking. MEDCHEMCOMM 2016; 7:184-189. [PMID: 26973774 PMCID: PMC4784703 DOI: 10.1039/c5md00316d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The aminoglycoside 6'-N-acetyltransferase type Ib, AAC(6')-Ib, confers resistance to clinically relevant aminoglycosides and is the most widely distributed enzyme among AAC(6')-I-producing Gram-negative pathogens. An alternative to counter the action of this enzyme is the development of inhibitors. Glide is a computational strategy for rapidly docking ligands to protein sites and estimating their binding affinities. We docked a collection of 280,000 compounds from 7 sub-libraries of the Chembridge library as ligands to the aminoglycoside binding site of AAC(6')-Ib. We identified a compound, 1-[3-(2-aminoethyl)benzyl]-3-(piperidin-1-ylmethyl)pyrrolidin-3-ol (compound 1), that inhibited the acetylation of aminoglycosides in vitro with IC50 values of 39.7 and 34.9 µM when the aminoglycoside substrates assayed were kanamycin A or amikacin, respectively. The growth of an amikacin-resistant Acinetobacter baumannii clinical strain was inhibited in the presence of a combination of amikacin and compound 1.
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Affiliation(s)
- Kevin Chiem
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92834-6850, United States
| | - Saumya Jani
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92834-6850, United States
| | - Brooke Fuentes
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92834-6850, United States
| | - David L. Lin
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92834-6850, United States
| | - Madeline E. Rasche
- Center for Applied Biotechnology Studies, Department of Chemistry and Biochemistry, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92834-6850, United States
| | - Marcelo E. Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92834-6850, United States
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166
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Koteva K, King AM, Capretta A, Wright GD. Total Synthesis and Activity of the Metallo-β-lactamase Inhibitor Aspergillomarasmine A. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201510057] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Kalinka Koteva
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
| | - Andrew M. King
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
| | - Alfredo Capretta
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
- Department of Chemistry and Chemical Biology; McMaster University; 1280 Main Street West Hamilton ON Canada
| | - Gerard D. Wright
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
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167
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Koteva K, King AM, Capretta A, Wright GD. Total Synthesis and Activity of the Metallo-β-lactamase Inhibitor Aspergillomarasmine A. Angew Chem Int Ed Engl 2015; 55:2210-2. [PMID: 26709849 DOI: 10.1002/anie.201510057] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Indexed: 01/03/2023]
Affiliation(s)
- Kalinka Koteva
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
| | - Andrew M. King
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
| | - Alfredo Capretta
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
- Department of Chemistry and Chemical Biology; McMaster University; 1280 Main Street West Hamilton ON Canada
| | - Gerard D. Wright
- Michael G. DeGroote Institute for Infectious Disease Research; McMaster University; 1280 Main Street West Hamilton ON Canada
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168
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Mendes RE, Castanheira M, Gasink L, Stone GG, Nichols WW, Flamm RK, Jones RN. β-Lactamase Characterization of Gram-Negative Pathogens Recovered from Patients Enrolled in the Phase 2 Trials for Ceftazidime-Avibactam: Clinical Efficacies Analyzed against Subsets of Molecularly Characterized Isolates. Antimicrob Agents Chemother 2015; 60:1328-35. [PMID: 26666936 PMCID: PMC4775982 DOI: 10.1128/aac.01173-15] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 12/05/2015] [Indexed: 11/30/2022] Open
Abstract
The correlation of the clinical efficacies of ceftazidime-avibactam and comparators (carbapenems) was evaluated against baseline Gram-negative isolates having characterized β-lactam resistance mechanisms from complicated urinary tract infection (cUTI) and complicated intra-abdominal infection (cIAI) phase 2 trials. Enterobacteriaceae displaying ceftriaxone and/or ceftazidime MICs of ≥ 2 μg/ml (69 isolates) and nonfermentative Gram-negative bacilli (NF-GNB [three isolates]) with ceftazidime MICs of ≥ 16 μg/ml were characterized for their narrow- and extended-spectrum β-lactamase (ESBL) content. Enterobacteriaceae (one isolate) and NF-GNB (three isolates) with imipenem/meropenem MICs of ≥ 2 and ≥ 16 μg/ml, respectively, were tested for carbapenemases. All cUTI E. coli had the lineage background investigated (ST131-like versus non-ST131-like). The primary efficacy endpoint was microbiological response (eradication) at test of cure (TOC) for cUTI and clinical response (inferred microbiological eradication) at TOC for cIAI. A total of 34.1% of baseline cUTI (36.4%) and cIAI (33.1%) pathogens met the MIC-based screening criteria (screen positive). All screen-positive cUTI pathogens were CTX-M-producing E. coli, except for one E. cloacae isolate with AmpC overexpression. The majority (66.7%) of screen-positive cIAI isolates produced CTX-M-type coupled with a diverse array of other β-lactamases. Similar favorable responses were observed with ceftazidime-avibactam (93.3%) and carbapenems (90.9%), when a non-ESBL Enterobacteriaceae isolate was recovered at the baseline visit. When an ESBL Enterobacteriaceae isolate was present, the favorable responses were 85.7% and 80.0% with ceftazidime-avibactam and carbapenems, respectively. Higher favorable responses were observed with ceftazidime-avibactam (75.0%) than with carbapenems (66.7%) when an ST131-like E. coli isolate was recovered at baseline, as when a non-ST131-like isolate was present (93.8% versus 86.7%, respectively). The efficacy of ceftazidime-avibactam was similar to that of carbapenems for treatment of cUTI and cIAI caused by ESBL organisms.
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Affiliation(s)
| | | | - Leanne Gasink
- AstraZeneca Pharmaceuticals LP, Waltham, Massachusetts, USA
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169
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References. Antibiotics (Basel) 2015. [DOI: 10.1128/9781555819316.refs] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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170
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Pagès JM, Peslier S, Keating TA, Lavigne JP, Nichols WW. Role of the Outer Membrane and Porins in Susceptibility of β-Lactamase-Producing Enterobacteriaceae to Ceftazidime-Avibactam. Antimicrob Agents Chemother 2015; 60:1349-59. [PMID: 26666933 PMCID: PMC4775948 DOI: 10.1128/aac.01585-15] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 12/05/2015] [Indexed: 01/21/2023] Open
Abstract
This study examined the activity of the novel antimicrobial combination ceftazidime-avibactam against Enterobacteriaceae exhibiting different outer membrane permeability profiles, specifically with or without porins and with or without expression of the main efflux pump (AcrAB-TolC). The addition of the outer membrane permeabilizer polymyxin B nonapeptide increased the antibacterial activities of avibactam alone, ceftazidime alone, and ceftazidime-avibactam against the characterized clinical isolates of Escherichia coli, Enterobacter aerogenes, and Klebsiella pneumoniae. This enhancement of activities was mainly due to increased passive penetration of compounds since inhibition of efflux by the addition of phenylalanine-arginine β-naphthylamide affected the MICs minimally. OmpF (OmpK35) or OmpC (OmpK36) pores were not the major route by which avibactam crossed the outer membranes of E. coli and K. pneumoniae. In contrast, Omp35 and Omp36 allowed diffusion of avibactam across the outer membrane of E. aerogenes, although other diffusion channels for avibactam were also present in that species. It was clear that outer membrane permeability and outer membrane pore-forming proteins play a key role in the activity of ceftazidime-avibactam. Nevertheless, the MICs of ceftazidime-avibactam (with 4 mg/liter avibactam) against the ceftazidime-resistant clinical isolates of the three species of Enterobacteriaceae studied were ≤ 8 mg/liter, regardless of outer membrane permeability changes resulting from an absence of defined porin proteins or upregulation of efflux.
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Affiliation(s)
- Jean-Marie Pagès
- UMR_MD-1, Aix-Marseille Université, IRBA, Transporteurs Membranaires, Chimiorésistance et Drug Design, Marseille, France
| | - Sabine Peslier
- UMR_MD-1, Aix-Marseille Université, IRBA, Transporteurs Membranaires, Chimiorésistance et Drug Design, Marseille, France
| | - Thomas A Keating
- AstraZeneca Infection Innovative Medicines, Waltham, Massachusetts, USA
| | - Jean-Philippe Lavigne
- Institut National de la Santé et de la Recherche Médicale, U1047, Université Montpellier 1, Nîmes, France Department of Microbiology, University Hospital Caremeau, Nîmes, France
| | - Wright W Nichols
- AstraZeneca Infection Innovative Medicines, Waltham, Massachusetts, USA
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171
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Falconer SB, Reid-Yu SA, King AM, Gehrke SS, Wang W, Britten JF, Coombes BK, Wright GD, Brown ED. Zinc Chelation by a Small-Molecule Adjuvant Potentiates Meropenem Activity in Vivo against NDM-1-Producing Klebsiella pneumoniae. ACS Infect Dis 2015; 1:533-43. [PMID: 27623408 DOI: 10.1021/acsinfecdis.5b00033] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The widespread emergence of antibiotic drug resistance has resulted in a worldwide healthcare crisis. In particular, the extensive use of β-lactams, a highly effective class of antibiotics, has been a driver for pervasive β-lactam resistance. Among the most important resistance determinants are the metallo-β-lactamases (MBL), which are zinc-requiring enzymes that inactivate nearly all classes of β-lactams, including the last-resort carbapenem antibiotics. The urgent need for new compounds targeting MBL resistance mechanisms has been widely acknowledged; however, the development of certain types of compounds-namely metal chelators-is actively avoided due to host toxicity concerns. The work herein reports the identification of a series of zinc-selective spiro-indoline-thiadiazole analogues that, in vitro, potentiate β-lactam antibiotics against an MBL-carrying pathogen by withholding zinc availability. This study demonstrates the ability of one such analogue to inhibit NDM-1 in vitro and, using a mouse model of infection, shows that combination treatment of the respective analogue with meropenem results in a significant decrease in bacterial burden in contrast to animals that received antibiotic treatment alone. These results support the therapeutic potential of these chelators in overcoming antibiotic resistance.
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Affiliation(s)
- Shannon B. Falconer
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | - Sarah A. Reid-Yu
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | - Andrew M. King
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | - Sebastian S. Gehrke
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | - Wenliang Wang
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | - James F. Britten
- Department
of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Brian K. Coombes
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | - Gerard D. Wright
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | - Eric D. Brown
- M.
G. DeGroote Institute for Infectious Disease Research and Department
of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
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172
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Bush K. A resurgence of β-lactamase inhibitor combinations effective against multidrug-resistant Gram-negative pathogens. Int J Antimicrob Agents 2015; 46:483-93. [DOI: 10.1016/j.ijantimicag.2015.08.011] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 08/20/2015] [Indexed: 10/23/2022]
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173
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Bollenbach T. Antimicrobial interactions: mechanisms and implications for drug discovery and resistance evolution. Curr Opin Microbiol 2015; 27:1-9. [DOI: 10.1016/j.mib.2015.05.008] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/06/2015] [Accepted: 05/08/2015] [Indexed: 01/06/2023]
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174
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Mawal Y, Critchley IA, Riccobene TA, Talley AK. Ceftazidime-avibactam for the treatment of complicated urinary tract infections and complicated intra-abdominal infections. Expert Rev Clin Pharmacol 2015; 8:691-707. [PMID: 26420166 DOI: 10.1586/17512433.2015.1090874] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Treatment of complicated urinary tract infections and complicated intra-abdominal infections is increasingly difficult due to the rising prevalence of multidrug-resistant Gram-negative bacteria. Ceftazidime-avibactam is a combination of the established third-generation cephalosporin ceftazidime with avibactam, a novel non-β-lactam β-lactamase inhibitor, which restores the activity of ceftazidime against many β-lactamase-producing Gram-negative bacteria, including extended-spectrum β-lactamases and Klebsiella pneumoniae carbapenemases. Clinical and nonclinical studies supporting the safety and efficacy of ceftazidime-avibactam include microbiological surveillance studies of clinically relevant pathogens, in vivo animal models of infection, pharmacokinetic/pharmacodynamic target attainment analyses, Phase I clinical pharmacology studies, and Phase II/III studies in the treatment of complicated intra-abdominal infections and complicated urinary tract infections, including patients with ceftazidime-nonsusceptible Gram-negative infections.
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Affiliation(s)
- Yogesh Mawal
- a 1 Forest Laboratories, Inc., a subsidiary of Allergan plc (formerly Actavis plc) , New Jersey, USA
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175
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In Vitro Activities of Ceftazidime-Avibactam, Aztreonam-Avibactam, and a Panel of Older and Contemporary Antimicrobial Agents against Carbapenemase-Producing Gram-Negative Bacilli. Antimicrob Agents Chemother 2015; 59:7842-6. [PMID: 26392487 DOI: 10.1128/aac.02019-15] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 09/12/2015] [Indexed: 12/16/2022] Open
Abstract
Among 177 carbapenemase-producing Gram-negative bacilli (108 KPC, 32 NDM, 11 IMP, 8 OXA-48, 4 OXA-181, 2 OXA-232, 5 IMI, 4 VIM, and 3 SME producers), aztreonam-avibactam was active against all isolates except two NDM producers with elevated MICs of 8/4 and 16/4 mg/liter; ceftazidime-avibactam was active against all KPC-, IMI-, SME-, and most OXA-48 group-producing isolates (93%) but not metallo-β-lactamase producers. Among older and contemporary antimicrobials, the most active were colistin, tigecycline, and fosfomycin, with overall susceptibilities of 88%, 79%, and 78%, respectively.
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176
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Meropenem-RPX7009 Concentrations in Plasma, Epithelial Lining Fluid, and Alveolar Macrophages of Healthy Adult Subjects. Antimicrob Agents Chemother 2015; 59:7232-9. [PMID: 26349830 DOI: 10.1128/aac.01713-15] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 09/03/2015] [Indexed: 11/20/2022] Open
Abstract
The steady-state concentrations of meropenem and the β-lactamase inhibitor RPX7009 in plasma, epithelial lining fluid (ELF), and alveolar macrophage (AM) concentrations were obtained in 25 healthy, nonsmoking adult subjects. Subjects received a fixed combination of meropenem (2 g) and RPX7009 (2 g) administered every 8 h, as a 3-h intravenous infusion, for a total of three doses. A bronchoscopy and bronchoalveolar lavage were performed once in each subject at 1.5, 3.25, 4, 6, or 8 h after the start of the last infusion. Meropenem and RPX7009 achieved a similar time course and magnitude of concentrations in plasma and ELF. The mean pharmacokinetic parameters ± the standard deviations of meropenem and RPX7009 determined from serial plasma concentrations were as follows: Cmax = 58.2 ± 10.8 and 59.0 ± 8.4 μg/ml, Vss = 16.3 ± 2.6 and 17.6 ± 2.6 liters; CL = 11.1 ± 2.1 and 10.1 ± 1.9 liters/h, and t1/2 = 1.03 ± 0.15 and 1.27 ± 0.21 h, respectively. The intrapulmonary penetrations of meropenem and RPX7009 were ca. 63 and 53%, respectively, based on the area under the concentration-time curve from 0 to 8 h (AUC0-8) values of ELF and total plasma concentrations. When unbound plasma concentrations were considered, ELF penetrations were 65 and 79% for meropenem and RPX7009, respectively. Meropenem concentrations in AMs were below the quantitative limit of detection, whereas median concentrations of RPX7009 in AMs ranged from 2.35 to 6.94 μg/ml. The results from the present study lend support to exploring a fixed combination of meropenem (2 g) and RPX7009 (2 g) for the treatment of lower respiratory tract infections caused by meropenem-resistant Gram-negative pathogens susceptible to the combination of meropenem-RPX7009.
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177
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Zowawi HM, Harris PNA, Roberts MJ, Tambyah PA, Schembri MA, Pezzani MD, Williamson DA, Paterson DL. The emerging threat of multidrug-resistant Gram-negative bacteria in urology. Nat Rev Urol 2015; 12:570-84. [PMID: 26334085 DOI: 10.1038/nrurol.2015.199] [Citation(s) in RCA: 239] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Antibiotic resistance in Gram-negative uropathogens is a major global concern. Worldwide, the prevalence of Enterobacteriaceae that produce extended-spectrum β-lactamase or carbapenemase enzymes continues to increase at alarming rates. Likewise, resistance to other antimicrobial agents including aminoglycosides, sulphonamides and fluoroquinolones is also escalating rapidly. Bacterial resistance has major implications for urological practice, particularly in relation to catheter-associated urinary tract infections (UTIs) and infectious complications following transrectal-ultrasonography-guided biopsy of the prostate or urological surgery. Although some new drugs with activity against Gram-negative bacteria with highly resistant phenotypes will become available in the near future, the existence of a single agent with activity against the great diversity of resistance is unlikely. Responding to the challenges of Gram-negative resistance will require a multifaceted approach including considered use of current antimicrobial agents, improved diagnostics (including the rapid detection of resistance) and surveillance, better adherence to basic measures of infection prevention, development of new antibiotics and research into non-antibiotic treatment and preventive strategies.
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Affiliation(s)
- Hosam M Zowawi
- The University of Queensland, UQ Centre for Clinical Research, Building 71/918 Royal Brisbane Hospital, Herston, QLD 4006, Australia
| | - Patrick N A Harris
- The University of Queensland, UQ Centre for Clinical Research, Building 71/918 Royal Brisbane Hospital, Herston, QLD 4006, Australia
| | - Matthew J Roberts
- The University of Queensland, UQ Centre for Clinical Research, Building 71/918 Royal Brisbane Hospital, Herston, QLD 4006, Australia
| | - Paul A Tambyah
- Division of Infectious Diseases, National University Health System, 1E Kent Ridge Road, 119228, Singapore
| | - Mark A Schembri
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - M Diletta Pezzani
- Department of Biomedical and Clinical Sciences L. Sacco, University of Milan, G. B. Grassi 74, 20157 Milan, Italy
| | - Deborah A Williamson
- Department of Pathology, University of Otago, 23A Mein Street, Newtown, Wellington 6242, New Zealand
| | - David L Paterson
- The University of Queensland, UQ Centre for Clinical Research, Building 71/918 Royal Brisbane Hospital, Herston, QLD 4006, Australia
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178
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Zmarlicka MT, Nailor MD, Nicolau DP. Impact of the New Delhi metallo-beta-lactamase on beta-lactam antibiotics. Infect Drug Resist 2015; 8:297-309. [PMID: 26345624 PMCID: PMC4554481 DOI: 10.2147/idr.s39186] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Since the first New Delhi metallo-beta-lactamase (NDM) report in 2009, NDM has spread globally causing various types of infections. NDM-positive organisms produce in vitro resistance phenotypes to carbapenems and many other antimicrobials. It is thus surprising that the literature examining clinical experiences with NDM does not report corresponding poor clinical outcomes. There are many instances where good clinical outcomes are described, despite a mismatch between administered antimicrobials and resistant in vitro susceptibilities. Available in vitro data for either monotherapy or combination therapy does not provide an explanation for these observations. However, animal studies do begin to shed more light on this phenomenon. They imply that the in vivo expression of NDM may not confer clinical resistance to all cephalosporin and carbapenem antibiotics as predicted by in vitro testing but other resistance mechanisms need to be present to generate a resistant phenotype. As such, previously abandoned therapies, particularly carbapenems and beta-lactamase inhibitor combinations, may retain utility against infections caused by NDM producers.
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Affiliation(s)
| | - Michael D Nailor
- School of Pharmacy, Department of Pharmacy Practice, University of Connecticut, Storrs, CT, USA
| | - David P Nicolau
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT, USA
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179
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Ruppé É, Woerther PL, Barbier F. Mechanisms of antimicrobial resistance in Gram-negative bacilli. Ann Intensive Care 2015; 5:61. [PMID: 26261001 PMCID: PMC4531117 DOI: 10.1186/s13613-015-0061-0] [Citation(s) in RCA: 251] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 07/23/2015] [Indexed: 02/07/2023] Open
Abstract
The burden of multidrug resistance in Gram-negative bacilli (GNB) now represents a daily issue for the management of antimicrobial therapy in intensive care unit (ICU) patients. In Enterobacteriaceae, the dramatic increase in the rates of resistance to third-generation cephalosporins mainly results from the spread of plasmid-borne extended-spectrum beta-lactamase (ESBL), especially those belonging to the CTX-M family. The efficacy of beta-lactam/beta-lactamase inhibitor associations for severe infections due to ESBL-producing Enterobacteriaceae has not been adequately evaluated in critically ill patients, and carbapenems still stands as the first-line choice in this situation. However, carbapenemase-producing strains have emerged worldwide over the past decade. VIM- and NDM-type metallo-beta-lactamases, OXA-48 and KPC appear as the most successful enzymes and may threaten the efficacy of carbapenems in the near future. ESBL- and carbapenemase-encoding plasmids frequently bear resistance determinants for other antimicrobial classes, including aminoglycosides (aminoglycoside-modifying enzymes or 16S rRNA methylases) and fluoroquinolones (Qnr, AAC(6′)-Ib-cr or efflux pumps), a key feature that fosters the spread of multidrug resistance in Enterobacteriaceae. In non-fermenting GNB such as Pseudomonas aeruginosa, Acinetobacter baumannii and Stenotrophomonas maltophilia, multidrug resistance may emerge following the sole occurrence of sequential chromosomal mutations, which may lead to the overproduction of intrinsic beta-lactamases, hyper-expression of efflux pumps, target modifications and permeability alterations. P. aeruginosa and A. baumannii also have the ability to acquire mobile genetic elements encoding resistance determinants, including carbapenemases. Available options for the treatment of ICU-acquired infections due to carbapenem-resistant GNB are currently scarce, and recent reports emphasizing the spread of colistin resistance in environments with high volume of polymyxins use elicit major concern.
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Affiliation(s)
- Étienne Ruppé
- Department of Infectious Diseases, Genomic Research Laboratory, Geneva University Hospitals, Geneva, Switzerland,
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180
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Caselli E, Romagnoli C, Vahabi R, Taracila MA, Bonomo RA, Prati F. Click Chemistry in Lead Optimization of Boronic Acids as β-Lactamase Inhibitors. J Med Chem 2015; 58:5445-58. [PMID: 26102369 DOI: 10.1021/acs.jmedchem.5b00341] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Boronic acid transition-state inhibitors (BATSIs) represent one of the most promising classes of β-lactamase inhibitors. Here we describe a new class of BATSIs, namely, 1-amido-2-triazolylethaneboronic acids, which were synthesized by combining the asymmetric homologation of boronates with copper-catalyzed azide-alkyne cycloaddition for the stereoselective insertion of the amido group and the regioselective formation of the 1,4-disubstituted triazole, respectively. This synthetic pathway, which avoids intermediate purifications, proved to be flexible and efficient, affording in good yields a panel of 14 BATSIs bearing three different R1 amide side chains (acetamido, benzylamido, and 2-thienylacetamido) and several R substituents on the triazole. This small library was tested against two clinically relevant class C β-lactamases from Enterobacter spp. and Pseudomonas aeruginosa. The K(i) value of the best compound (13a) was as low as 4 nM with significant reduction of bacterial resistance to the combination of cefotaxime/13a.
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Affiliation(s)
- Emilia Caselli
- †Department of Life Science, University of Modena and Reggio Emilia, via Campi 103, 41125 Modena, Italy
| | - Chiara Romagnoli
- †Department of Life Science, University of Modena and Reggio Emilia, via Campi 103, 41125 Modena, Italy
| | - Roza Vahabi
- †Department of Life Science, University of Modena and Reggio Emilia, via Campi 103, 41125 Modena, Italy
| | - Magdalena A Taracila
- §Departments of Medicine, Pharmacology, Biochemistry, and Molecular Biology and Microbiology, Case Western Reserve University, , Cleveland, Ohio 44106, United States
| | - Robert A Bonomo
- ‡Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, Ohio 44106, United States.,§Departments of Medicine, Pharmacology, Biochemistry, and Molecular Biology and Microbiology, Case Western Reserve University, , Cleveland, Ohio 44106, United States
| | - Fabio Prati
- †Department of Life Science, University of Modena and Reggio Emilia, via Campi 103, 41125 Modena, Italy
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181
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Perez F, Adachi J, Bonomo RA. Antibiotic-resistant gram-negative bacterial infections in patients with cancer. Clin Infect Dis 2015; 59 Suppl 5:S335-9. [PMID: 25352627 DOI: 10.1093/cid/ciu612] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Patients with cancer are at high risk for infections caused by antibiotic resistant gram-negative bacteria. In this review, we summarize trends among the major pathogens and clinical syndromes associated with antibiotic resistant gram-negative bacterial infection in patients with malignancy, with special attention to carbapenem and expanded-spectrum β-lactam resistance in Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia--all major threats to our cancer patients. Optimal therapy for these antibiotic-resistant pathogens still remains to be determined.
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Affiliation(s)
- Federico Perez
- Medical and Research Services, Louis Stokes Cleveland Veterans Affairs Medical Center Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Javier Adachi
- Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, Houston
| | - Robert A Bonomo
- Medical and Research Services, Louis Stokes Cleveland Veterans Affairs Medical Center Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio
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182
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Courtney CM, Chatterjee A. Sequence-Specific Peptide Nucleic Acid-Based Antisense Inhibitors of TEM-1 β-Lactamase and Mechanism of Adaptive Resistance. ACS Infect Dis 2015; 1:253-63. [PMID: 27622741 DOI: 10.1021/acsinfecdis.5b00042] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The recent surge of drug-resistant superbugs and shrinking antibiotic pipeline are serious challenges to global health. In particular, the emergence of β-lactamases has caused extensive resistance against the most frequently prescribed class of β-lactam antibiotics. Here, we develop novel synthetic peptide nucleic acid-based antisense inhibitors that target the start codon and ribosomal binding site of the TEM-1 β-lactamase transcript and act via translation inhibition mechanism. We show that these antisense inhibitors are capable of resensitizing drug-resistant Escherichia coli to β-lactam antibiotics exhibiting 10-fold reduction in the minimum inhibitory concentration (MIC). To study the mechanism of resistance, we adapted E. coli at MIC levels of the β-lactam/antisense inhibitor combination and observed a nonmutational, bet-hedging based adaptive antibiotic resistance response as evidenced by phenotypic heterogeneity as well as heterogeneous expression of key stress response genes. Our data show that both the development of new antimicrobials and an understanding of cellular response during the development of tolerance could aid in mitigating the impending antibiotic crisis.
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Affiliation(s)
- Colleen M. Courtney
- Department of Chemical and Biological Engineering and ‡BioFrontiers
Institute, 596 UCB, University of Colorado, Boulder, Colorado 80303, United States
| | - Anushree Chatterjee
- Department of Chemical and Biological Engineering and ‡BioFrontiers
Institute, 596 UCB, University of Colorado, Boulder, Colorado 80303, United States
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183
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Singh R, Kim A, Tanudra MA, Harris JJ, McLaughlin RE, Patey S, O'Donnell JP, Bradford PA, Eakin AE. Pharmacokinetics/pharmacodynamics of a β-lactam and β-lactamase inhibitor combination: a novel approach for aztreonam/avibactam. J Antimicrob Chemother 2015; 70:2618-26. [PMID: 26024868 DOI: 10.1093/jac/dkv132] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 04/22/2015] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES The combination of aztreonam/avibactam has promising activity against MDR Gram-negative pathogens producing metallo-β-lactamases (MBLs), such as New Delhi MBL-1. Pharmacokinetic (PK)/pharmacodynamic (PD) understanding of this combination is critical for optimal clinical dose selection. This study focuses on the determination of an integrated PK/PD approach for aztreonam/avibactam across multiple clinical Enterobacteriaceae strains. METHODS Six clinical Enterobacteriaceae isolates expressing MBLs and ESBLs were studied in an in vitro hollow-fibre infection model (HFIM) using various dosing regimens simulating human-like PK for aztreonam/avibactam. The neutropenic murine thigh infection model was used for in vivo validation against two bacterial strains. RESULTS MIC values of aztreonam/avibactam for the isolates ranged from 0.125 to 8 mg/L. Using a constant infusion of avibactam at 4 mg/L, the aztreonam PK/PD index was observed as % fT >MIC. Studies performed in the presence of a fixed dose of aztreonam revealed that the efficacy of avibactam correlates best with percentage of time above a critical threshold concentration of 2-2.5 mg/L. These conclusions translated well to the efficacy observed in the murine thigh model, demonstrating in vivo validation of the in vitro PK/PD target. CONCLUSIONS PK/PD evaluations for aztreonam/avibactam in HFIM yielded a single target across strains with a wide MIC range. This integrated approach could be easily applied for forecasting clinically efficacious doses for β-lactam/β-lactamase inhibitor combinations.
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Affiliation(s)
- Renu Singh
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - Aryun Kim
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - M Angela Tanudra
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - Jennifer J Harris
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - Robert E McLaughlin
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - Sara Patey
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - John P O'Donnell
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - Patricia A Bradford
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
| | - Ann E Eakin
- AstraZeneca Infection Innovative Medicines, 35 Gatehouse Drive, Waltham, MA 02451, USA
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184
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Activity of Imipenem with Relebactam against Gram-Negative Pathogens from New York City. Antimicrob Agents Chemother 2015; 59:5029-31. [PMID: 26014931 DOI: 10.1128/aac.00830-15] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 05/17/2015] [Indexed: 11/20/2022] Open
Abstract
Imipenem with relebactam was active against Escherichia coli, Klebsiella pneumoniae, and Enterobacter spp., including K. pneumoniae carbapenemase (KPC)-producing isolates. Loss of OmpK36 in KPC-producing K. pneumoniae isolates affected the susceptibility of this combination. Enhanced activity was evident against Pseudomonas aeruginosa, including isolates with depressed oprD and increased ampC expression. However, the addition of relebactam to imipenem did not provide added benefit against Acinetobacter baumannii. The combination of imipenem with relebactam demonstrated activity against KPC-producing Enterobacteriaceae and multidrug-resistant P. aeruginosa.
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185
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Papp-Wallace KM, Bajaksouzian S, Abdelhamed AM, Foster AN, Winkler ML, Gatta JA, Nichols WW, Testa R, Bonomo RA, Jacobs MR. Activities of ceftazidime, ceftaroline, and aztreonam alone and combined with avibactam against isogenic Escherichia coli strains expressing selected single β-lactamases. Diagn Microbiol Infect Dis 2015; 82:65-9. [PMID: 25737290 PMCID: PMC4415506 DOI: 10.1016/j.diagmicrobio.2015.02.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/03/2015] [Accepted: 02/08/2015] [Indexed: 11/18/2022]
Abstract
Avibactam is a novel β-lactamase inhibitor that restores the activity of otherwise hydrolyzed β-lactams against Gram-negative bacteria expressing different classes of serine β-lactamases. In the last decade, β-lactam-avibactam combinations were tested against a variety of clinical isolates expressing multiple commonly encountered β-lactamases. Here, we analyzed isogenic Escherichia coli strains expressing selected single β-lactamase genes that were not previously tested or were not characterized in an isogenic background. The activities of ceftazidime, ceftaroline, and aztreonam alone and in combination with 4 mg/L of avibactam, as well as comparator agents, were assessed against a unique collection of isogenic strains of E. coli carrying selected extended-spectrum, inhibitor-resistant, and/or carbapenem-hydrolyzing bla genes. When combined with avibactam, ceftazidime, ceftaroline, or aztreonam MICs were reduced for 91.4%, 80.0%, and 80.0% of isolates, respectively. The data presented add to our understanding of the microbiologic spectrum of these β-lactams with avibactam and serve as a reference for further studies.
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Affiliation(s)
- Krisztina M Papp-Wallace
- Department of Medicine, Case Western Reserve University, Cleveland, OH; Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH
| | - Saralee Bajaksouzian
- Department of Medicine, Case Western Reserve University, Cleveland, OH; Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH
| | - Ayman M Abdelhamed
- Department of Medicine, Case Western Reserve University, Cleveland, OH; Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH
| | - Altreisha N Foster
- Department of Medicine, Case Western Reserve University, Cleveland, OH; Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH
| | - Marisa L Winkler
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH; Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH
| | - Julian A Gatta
- Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH
| | - Wright W Nichols
- AstraZeneca Pharmaceuticals, Infection Innovative Medicines, Waltham, MA
| | - Raymond Testa
- AstraZeneca Pharmaceuticals, Infection Innovative Medicines, Waltham, MA
| | - Robert A Bonomo
- Department of Medicine, Case Western Reserve University, Cleveland, OH; Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH; Department of Pharmacology, Case Western Reserve University, Cleveland, OH; Department of Biochemistry, Case Western Reserve University, Cleveland, OH; Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH.
| | - Michael R Jacobs
- Department of Medicine, Case Western Reserve University, Cleveland, OH; Department of Pathology, University Hospitals Case Medical Center, Cleveland, OH.
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186
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Olsen I. New promising β-lactamase inhibitors for clinical use. Eur J Clin Microbiol Infect Dis 2015; 34:1303-8. [DOI: 10.1007/s10096-015-2375-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 03/23/2015] [Indexed: 01/15/2023]
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187
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Murphy-Benenato KE, Bhagunde PR, Chen A, Davis HE, Durand-Réville TF, Ehmann DE, Galullo V, Harris JJ, Hatoum-Mokdad H, Jahić H, Kim A, Manjunatha MR, Manyak EL, Mueller J, Patey S, Quiroga O, Rooney M, Sha L, Shapiro AB, Sylvester M, Tan B, Tsai AS, Uria-Nickelsen M, Wu Y, Zambrowski M, Zhao SX. Discovery of Efficacious Pseudomonas aeruginosa-Targeted Siderophore-Conjugated Monocarbams by Application of a Semi-mechanistic Pharmacokinetic/Pharmacodynamic Model. J Med Chem 2015; 58:2195-205. [DOI: 10.1021/jm501506f] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - M. R. Manjunatha
- Infection
Innovative Medicines, AstraZeneca India Pvt. Ltd., Bellary Road, Bangalore 560024, India
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188
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β-lactam and β-lactamase inhibitor combinations in the treatment of extended-spectrum β-lactamase producing Enterobacteriaceae: time for a reappraisal in the era of few antibiotic options? THE LANCET. INFECTIOUS DISEASES 2015; 15:475-85. [PMID: 25716293 DOI: 10.1016/s1473-3099(14)70950-8] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The spread of extended-spectrum β-lactamase (ESBL) genes in Enterobacteriaceae such as Escherichia coli or Klebsiella spp is a major challenge to modern medical practice. Carbapenems are the treatment of choice for serious infections caused by ESBL producers; however, carbapenem resistance has increased globally. ESBL producers might be susceptible to β-lactam-β-lactamase inhibitor (BLBLI) combination antibiotics such piperacillin-tazobactam or amoxicillin-clavulanate. These drugs are frequently avoided in serious infections caused by ESBL producers because of the inoculum effect in-vitro (especially for piperacillin-tazobactam), animal data suggesting inferior efficacy when compared with carbapenems, concerns about pharmacokinetic-pharmacodynamic drug target attainment with standard doses, and poor outcomes shown in some observational studies. Prospective cohort data and a meta-analysis suggest that BLBLIs are non-inferior to carbapenems in the treatment of bloodstream infections caused by ESBL producers. We examine why BLBLIs are perceived as inferior in the treatment of infection with ESBL producers, and discuss data that suggest these concerns might not be strongly supported by clinical evidence.
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189
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Lahiri SD, Mangani S, Jahić H, Benvenuti M, Durand-Reville TF, De Luca F, Ehmann DE, Rossolini GM, Alm RA, Docquier JD. Molecular basis of selective inhibition and slow reversibility of avibactam against class D carbapenemases: a structure-guided study of OXA-24 and OXA-48. ACS Chem Biol 2015; 10:591-600. [PMID: 25406838 DOI: 10.1021/cb500703p] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The Class D (or OXA-type) β-lactamases have expanded to be the most diverse group of serine β-lactamases with a highly heterogeneous β-lactam hydrolysis profile and are typically resistant to marketed β-lactamase inhibitors. Class D enzymes are increasingly found in multidrug resistant (MDR) Acinetobacter baumannii, Pseudomonas aeruginosa, and various species of the Enterobacteriaceae and are posing a serious threat to the clinical utility of β-lactams including the carbapenems, which are typically reserved as the drugs of last resort. Avibactam, a novel non-β-lactam β-lactamase inhibitor, not only inhibits all class A and class C β-lactamases but also has the promise of inhibition of certain OXA enzymes, thus extending the antibacterial activity of the β-lactam used in combination to the organisms that produce these enzymes. X-ray structures of OXA-24 and OXA-48 in complex with avibactam revealed the binding mode of this inhibitor in this diverse class of enzymes and provides a rationale for selective inhibition of OXA-48 members. Additionally, various subunits of the OXA-48 structure in the asymmetric unit provide snapshots of different states of the inhibited enzyme. Overall, these data provide the first structural evidence of the exceptionally slow reversibility observed with avibactam in class D β-lactamases. Mechanisms for acylation and deacylation of avibactam by class D enzymes are proposed, and the likely extent of inhibition of class D β-lactamases by avibactam is discussed.
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Affiliation(s)
| | | | | | | | | | | | | | - Gian Maria Rossolini
- Department of Experimental and Clinical
Medicine, University of Florence, Florence I-50134, Italy
- Clinical
Microbiology and Virology Unit, Florence Careggi University Hospital, Florence I-50134, Italy
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190
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Sgrignani J, Novati B, Colombo G, Grazioso G. Covalent docking of selected boron-based serine beta-lactamase inhibitors. J Comput Aided Mol Des 2015; 29:441-50. [DOI: 10.1007/s10822-015-9834-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/02/2015] [Indexed: 10/24/2022]
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191
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Leiros HKS, Edvardsen KSW, Bjerga GEK, Samuelsen Ø. Structural and biochemical characterization of VIM-26 shows that Leu224 has implications for the substrate specificity of VIM metallo-β-lactamases. FEBS J 2015; 282:1031-42. [DOI: 10.1111/febs.13200] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 01/13/2015] [Accepted: 01/14/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Hanna-Kirsti S. Leiros
- Norwegian Structural Biology Centre; Department of Chemistry; UiT The Arctic University of Norway; Tromsø Norway
| | - Kine Susann Waade Edvardsen
- Norwegian Structural Biology Centre; Department of Chemistry; UiT The Arctic University of Norway; Tromsø Norway
| | - Gro Elin Kjaereng Bjerga
- Norwegian Structural Biology Centre; Department of Chemistry; UiT The Arctic University of Norway; Tromsø Norway
| | - Ørjan Samuelsen
- Norwegian National Advisory Unit on Detection of Antimicrobial Resistance; Department of Microbiology and Infection Control; University Hospital of North Norway; Tromsø Norway
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192
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Andersen JL, He GX, Kakarla P, K C R, Kumar S, Lakra WS, Mukherjee MM, Ranaweera I, Shrestha U, Tran T, Varela MF. Multidrug efflux pumps from Enterobacteriaceae, Vibrio cholerae and Staphylococcus aureus bacterial food pathogens. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:1487-547. [PMID: 25635914 PMCID: PMC4344678 DOI: 10.3390/ijerph120201487] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/15/2015] [Indexed: 02/07/2023]
Abstract
Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations.
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Affiliation(s)
- Jody L Andersen
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Gui-Xin He
- Department of Clinical Laboratory and Nutritional Sciences, University of Massachusetts Lowell, Lowell, MA 01854, USA.
| | - Prathusha Kakarla
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Ranjana K C
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Sanath Kumar
- QC Laboratory, Harvest and Post-Harvest Technology Division, Central Institute of Fisheries Education (CIFE), Seven Bungalows, Versova, Andheri (W), Mumbai 400061, India.
| | - Wazir Singh Lakra
- QC Laboratory, Harvest and Post-Harvest Technology Division, Central Institute of Fisheries Education (CIFE), Seven Bungalows, Versova, Andheri (W), Mumbai 400061, India.
| | - Mun Mun Mukherjee
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Indrika Ranaweera
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Ugina Shrestha
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Thuy Tran
- Department of Clinical Laboratory and Nutritional Sciences, University of Massachusetts Lowell, Lowell, MA 01854, USA.
| | - Manuel F Varela
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
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193
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Pogue JM, Cohen DA, Marchaim D. Editorial commentary: Polymyxin-resistant Acinetobacter baumannii: urgent action needed. Clin Infect Dis 2015; 60:1304-7. [PMID: 25632011 PMCID: PMC4392843 DOI: 10.1093/cid/civ044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Accepted: 01/02/2015] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jason M Pogue
- Department of Pharmacy Services, Sinai-Grace Hospital, Detroit Medical Center, Wayne State University School of Medicine, Michigan
| | - David A Cohen
- Unit of Infectious Diseases, Assaf Harofeh Medical Center, Zerifin
| | - Dror Marchaim
- Unit of Infectious Diseases, Assaf Harofeh Medical Center, Zerifin Sackler School of Medicine, Tel-Aviv University, Israel
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194
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Harris PNA, Peleg AY, Iredell J, Ingram PR, Miyakis S, Stewardson AJ, Rogers BA, McBryde ES, Roberts JA, Lipman J, Athan E, Paul SK, Baker P, Harris-Brown T, Paterson DL. Meropenem versus piperacillin-tazobactam for definitive treatment of bloodstream infections due to ceftriaxone non-susceptible Escherichia coli and Klebsiella spp (the MERINO trial): study protocol for a randomised controlled trial. Trials 2015; 16:24. [PMID: 25623485 PMCID: PMC4311465 DOI: 10.1186/s13063-014-0541-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 12/22/2014] [Indexed: 12/20/2022] Open
Abstract
Background Gram-negative bacteria such as Escherichia coli or Klebsiella spp. frequently cause bloodstream infections. There has been a worldwide increase in resistance in these species to antibiotics such as third generation cephalosporins, largely driven by the acquisition of extended-spectrum beta-lactamase or plasmid-mediated AmpC enzymes. Carbapenems have been considered the most effective therapy for serious infections caused by such resistant bacteria; however, increased use creates selection pressure for carbapenem resistance, an emerging threat arising predominantly from the dissemination of genes encoding carbapenemases. Recent retrospective data suggest that beta-lactam/beta-lactamase inhibitor combinations, such as piperacillin-tazobactam, may be non-inferior to carbapenems for the treatment of bloodstream infection caused by extended-spectrum beta-lactamase-producers, if susceptible in vitro. This study aims to test this hypothesis in an effort to define carbapenem-sparing alternatives for these infections. Methods/Design The study will use a multicentre randomised controlled open-label non-inferiority trial design comparing two treatments, meropenem (standard arm) and piperacillin-tazobactam (carbapenem-sparing arm) in adult patients with bacteraemia caused by E. coli or Klebsiella spp. demonstrating non-susceptibility to third generation cephalosporins. Recruitment is planned to occur in sites across three countries (Australia, New Zealand and Singapore). A total sample size of 454 patients will be required to achieve 80% power to determine non-inferiority with a margin of 5%. Once randomised, definitive treatment will be for a minimum of 4 days, but up to 14 days with total duration determined by treating clinicians. Data describing demographic information, antibiotic use, co-morbid conditions, illness severity, source of infection and other risk factors will be collected. Vital signs, white cell count, use of vasopressors and days to bacteraemia clearance will be recorded up to day 7. The primary outcome measure will be mortality at 30 days, with secondary outcomes including days to clinical and microbiological resolution, microbiological failure or relapse, isolation of a multi-resistant organism or Clostridium difficile infection. Trial registration The MERINO trial is registered under the Australian New Zealand Clinical Trials Register (ANZCTR), reference number: ACTRN12613000532707 (registered 13 May 2013) and the US National Institute of Health ClinicalTrials.gov register, reference number: NCT02176122 (registered 24 June 2014). Electronic supplementary material The online version of this article (doi:10.1186/s13063-014-0541-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Patrick N A Harris
- University of Queensland Centre for Clinical Research, Building 71/918 Royal Brisbane & Women's Hospital Campus, Herston, 4029, Brisbane, QLD, Australia.
| | - Anton Y Peleg
- Department of Infectious Diseases, The Alfred Hospital, Melbourne, VIC, Australia.
| | - Jon Iredell
- Westmead Millenium Institute for Medical Research, Westmead Hospital, Sydney, NSW, Australia.
| | - Paul R Ingram
- Department of Microbiology and Infectious Diseases, Royal Perth Hospital, Perth, WA, Australia. .,School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, WA, Australia.
| | - Spiros Miyakis
- Department of Infectious Diseases, School of Medicine, University of Wollongong and The Wollongong Hospital, Wollongong, NSW, Australia.
| | - Andrew J Stewardson
- Department of Infectious Diseases, Austin Health, Melbourne, VIC, Australia.
| | | | - Emma S McBryde
- Victorian Infectious Diseases Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia.
| | - Jason A Roberts
- Burns Trauma and Critical Care Research Centre, The University of Queensland, Brisbane, QLD, Australia.
| | - Jeff Lipman
- Burns Trauma and Critical Care Research Centre, The University of Queensland, Brisbane, QLD, Australia.
| | - Eugene Athan
- Department of Infectious Disease, Barwon Health, Deakin University, Geelong, VIC, Australia.
| | - Sanjoy K Paul
- Clinical Trials & Biostatistics Unit, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.
| | - Peter Baker
- Queensland Clinical Trials and Biostatistics Centre, University of Queensland, Brisbane, QLD, Australia.
| | - Tiffany Harris-Brown
- University of Queensland Centre for Clinical Research, Building 71/918 Royal Brisbane & Women's Hospital Campus, Herston, 4029, Brisbane, QLD, Australia.
| | - David L Paterson
- University of Queensland Centre for Clinical Research, Building 71/918 Royal Brisbane & Women's Hospital Campus, Herston, 4029, Brisbane, QLD, Australia.
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195
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Pettinati I, Brem J, McDonough MA, Schofield CJ. Crystal structure of human persulfide dioxygenase: structural basis of ethylmalonic encephalopathy. Hum Mol Genet 2015; 24:2458-69. [PMID: 25596185 PMCID: PMC4383860 DOI: 10.1093/hmg/ddv007] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/13/2015] [Indexed: 01/08/2023] Open
Abstract
The ethylmalonic encephalopathy protein 1 (ETHE1) catalyses the oxygen-dependent oxidation of glutathione persulfide (GSSH) to give persulfite and glutathione. Mutations to the hETHE1 gene compromise sulfide metabolism leading to the genetic disease ethylmalonic encephalopathy. hETHE1 is a mono-iron binding member of the metallo-β-lactamase (MBL) fold superfamily. We report crystallographic analysis of hETHE1 in complex with iron to 2.6 Å resolution. hETHE1 contains an αββα MBL-fold, which supports metal-binding by the side chains of an aspartate and two histidine residues; three water molecules complete octahedral coordination of the iron. The iron binding hETHE1 enzyme is related to the ‘classical’ di-zinc binding MBL hydrolases involved in antibiotic resistance, but has distinctive features. The histidine and aspartate residues involved in iron-binding in ETHE1, occupy similar positions to those observed across both the zinc 1 and zinc 2 binding sites in classical MBLs. The active site of hETHE1 is very similar to an ETHE1-like enzyme from Arabidopsis thaliana (60% sequence identity). A channel leading to the active site is sufficiently large to accommodate a GSSH substrate. Some of the observed hETHE1 clinical mutations cluster in the active site region. The structure will serve as a basis for detailed functional and mechanistic studies on ETHE1 and will be useful in the development of selective MBL inhibitors.
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Affiliation(s)
- Ilaria Pettinati
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, UK
| | - Jürgen Brem
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, UK
| | - Michael A McDonough
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, UK
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196
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Hesterkamp T. Antibiotics Clinical Development and Pipeline. Curr Top Microbiol Immunol 2015; 398:447-474. [DOI: 10.1007/82_2015_451] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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197
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Abstract
Gram-positive organisms, including the pathogens Staphylococcus aureus, Streptococcus pneumoniae, and Enterococcus faecalis, have dynamic cell envelopes that mediate interactions with the environment and serve as the first line of defense against toxic molecules. Major components of the cell envelope include peptidoglycan (PG), which is a well-established target for antibiotics, teichoic acids (TAs), capsular polysaccharides (CPS), surface proteins, and phospholipids. These components can undergo modification to promote pathogenesis, decrease susceptibility to antibiotics and host immune defenses, and enhance survival in hostile environments. This chapter will cover the structure, biosynthesis, and important functions of major cell envelope components in gram-positive bacteria. Possible targets for new antimicrobials will be noted.
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198
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Brooks BD, Brooks AE. Therapeutic strategies to combat antibiotic resistance. Adv Drug Deliv Rev 2014; 78:14-27. [PMID: 25450262 DOI: 10.1016/j.addr.2014.10.027] [Citation(s) in RCA: 207] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 10/20/2014] [Accepted: 10/22/2014] [Indexed: 12/16/2022]
Abstract
With multidrug resistant bacteria on the rise, new antibiotic approaches are required. Although a number of new small molecule antibiotics are currently in the development pipeline with many more in preclinical development, the clinical options and practices for infection control must be expanded. Biologics and non-antibiotic adjuvants offer this opportunity for expansion. Nevertheless, to avoid known mechanisms of resistance, intelligent combination approaches for multiple simultaneous and complimentary therapies must be designed. Combination approaches should extend beyond biologically active molecules to include smart controlled delivery strategies. Infection control must integrate antimicrobial stewardship, new antibiotic molecules, biologics, and delivery strategies into effective combination therapies designed to 1) fight the infection, 2) avoid resistance, and 3) protect the natural microbiome. This review explores these developing strategies in the context of circumventing current mechanisms of resistance.
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Affiliation(s)
| | - Amanda E Brooks
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84112, USA; Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND58108, USA.
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199
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Tang SS, Apisarnthanarak A, Hsu LY. Mechanisms of β-lactam antimicrobial resistance and epidemiology of major community- and healthcare-associated multidrug-resistant bacteria. Adv Drug Deliv Rev 2014; 78:3-13. [PMID: 25134490 DOI: 10.1016/j.addr.2014.08.003] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 05/07/2014] [Accepted: 08/11/2014] [Indexed: 12/14/2022]
Abstract
Alexander Fleming's discovery of penicillin heralded an age of antibiotic development and healthcare advances that are premised on the ability to prevent and treat bacterial infections both safely and effectively. The resultant evolution of antimicrobial resistant mechanisms and spread of bacteria bearing these genetic determinants of resistance are acknowledged to be one of the major public health challenges globally, and threatens to unravel the gains of the past decades. We describe the major mechanisms of resistance to β-lactam antibiotics - the most widely used and effective antibiotics currently - in both Gram-positive and Gram-negative bacteria, and also briefly detail the existing and emergent pharmacological strategies to overcome such resistance. The global epidemiology of the four major types of bacteria that are responsible for the bulk of antimicrobial-resistant infections in the healthcare setting - methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Enterobactericeae, and Acinetobacter baumannii - are also briefly described.
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Affiliation(s)
- Sarah S Tang
- Singapore General Hospital, Outram Road, Singapore 169608, Singapore.
| | | | - Li Yang Hsu
- National University Health System, 1E Kent Ridge Road, NUHS Tower Block Level 10, Singapore 119228, Singapore.
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200
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Powers RA, Swanson HC, Taracila MA, Florek NW, Romagnoli C, Caselli E, Prati F, Bonomo RA, Wallar BJ. Biochemical and structural analysis of inhibitors targeting the ADC-7 cephalosporinase of Acinetobacter baumannii. Biochemistry 2014; 53:7670-9. [PMID: 25380506 PMCID: PMC4263437 DOI: 10.1021/bi500887n] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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β-Lactam
resistance in Acinetobacter baumannii presents one
of the greatest challenges to contemporary antimicrobial chemotherapy.
Much of this resistance to cephalosporins derives from the expression
of the class C β-lactamase enzymes, known as Acinetobacter-derived cephalosporinases (ADCs). Currently, β-lactamase inhibitors
are structurally similar to β-lactam substrates and are not
effective inactivators of this class C cephalosporinase. Herein, two boronic acid transition state inhibitors
(BATSIs S02030 and SM23) that are chemically distinct from β-lactams
were designed and tested for inhibition of ADC enzymes. BATSIs SM23
and S02030 bind with high affinity to ADC-7, a chromosomal cephalosporinase
from Acinetobacter baumannii (Ki = 21.1 ± 1.9 nM and 44.5 ± 2.2 nM, respectively).
The X-ray crystal structures of ADC-7 were determined in both the
apo form (1.73 Å resolution) and in complex with S02030 (2.0
Å resolution). In the complex, S02030 makes several canonical
interactions: the O1 oxygen of S02030 is bound in the oxyanion hole,
and the R1 amide group makes key interactions with conserved residues
Asn152 and Gln120. In addition, the carboxylate group of the inhibitor
is meant to mimic the C3/C4 carboxylate found
in β-lactams. The C3/C4 carboxylate recognition
site in class C enzymes is comprised of Asn346 and Arg349 (AmpC numbering),
and these residues are conserved in ADC-7. Interestingly, in the ADC-7/S02030
complex, the inhibitor carboxylate group is observed to interact with
Arg340, a residue that distinguishes ADC-7 from the related class
C enzyme AmpC. A thermodynamic analysis suggests that ΔH driven compounds may be optimized to generate
new lead agents. The ADC-7/BATSI complex provides insight into recognition
of non-β-lactam inhibitors by ADC enzymes and offers a starting
point for the structure-based optimization of this class of novel
β-lactamase inhibitors against a key resistance target.
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Affiliation(s)
- Rachel A Powers
- Department of Chemistry, Grand Valley State University , 1 Campus Drive, Allendale, Michigan 49401, United States
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