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Abstract
The carbapenem family of β-lactam antibiotics displays a remarkably broad spectrum of bactericidal activity, exemplified by meropenem's phase II clinical trial success in patients with pulmonary tuberculosis, a devastating disease for which β-lactam drugs historically have been notoriously ineffective. The discovery and validation of l,d-transpeptidases (Ldts) as critical drug targets of bacterial cell-wall biosynthesis, which are only potently inhibited by the carbapenem and penem structural classes, gave an enzymological basis for the effectiveness of the first antitubercular β-lactams. Decades of study have delineated mechanisms of β-lactam inhibition of their canonical targets, the penicillin-binding proteins; however, open questions remain regarding the mechanisms of Ldt inhibition that underlie programs in drug design, particularly the optimization of kinetic behavior and potency. We have investigated critical features of mycobacterial Ldt inhibition and demonstrate here that the covalent inhibitor meropenem undergoes both reversible reaction and nonhydrolytic off-loading reactions from the cysteine transpeptidase LdtMt2 through a high-energy thioester adduct. Next-generation carbapenem optimization strategies should minimize adduct loss from unproductive mechanisms of Ldt adducts that reduce effective drug concentration.
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Affiliation(s)
- Trevor A Zandi
- T.C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218
| | - Craig A Townsend
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218
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2
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Mehta SC, Furey IM, Pemberton OA, Boragine DM, Chen Y, Palzkill T. KPC-2 β-lactamase enables carbapenem antibiotic resistance through fast deacylation of the covalent intermediate. J Biol Chem 2021; 296:100155. [PMID: 33273017 PMCID: PMC7895804 DOI: 10.1074/jbc.ra120.015050] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 11/24/2020] [Accepted: 12/03/2020] [Indexed: 01/23/2023] Open
Abstract
Serine active-site β-lactamases hydrolyze β-lactam antibiotics through the formation of a covalent acyl-enzyme intermediate followed by deacylation via an activated water molecule. Carbapenem antibiotics are poorly hydrolyzed by most β-lactamases owing to slow hydrolysis of the acyl-enzyme intermediate. However, the emergence of the KPC-2 carbapenemase has resulted in widespread resistance to these drugs, suggesting it operates more efficiently. Here, we investigated the unusual features of KPC-2 that enable this resistance. We show that KPC-2 has a 20,000-fold increased deacylation rate compared with the common TEM-1 β-lactamase. Furthermore, kinetic analysis of active site alanine mutants indicates that carbapenem hydrolysis is a concerted effort involving multiple residues. Substitution of Asn170 greatly decreases the deacylation rate, but this residue is conserved in both KPC-2 and non-carbapenemase β-lactamases, suggesting it promotes carbapenem hydrolysis only in the context of KPC-2. X-ray structure determination of the N170A enzyme in complex with hydrolyzed imipenem suggests Asn170 may prevent the inactivation of the deacylating water by the 6α-hydroxyethyl substituent of carbapenems. In addition, the Thr235 residue, which interacts with the C3 carboxylate of carbapenems, also contributes strongly to the deacylation reaction. In contrast, mutation of the Arg220 and Thr237 residues decreases the acylation rate and, paradoxically, improves binding affinity for carbapenems. Thus, the role of these residues may be ground state destabilization of the enzyme-substrate complex or, alternatively, to ensure proper alignment of the substrate with key catalytic residues to facilitate acylation. These findings suggest modifications of the carbapenem scaffold to avoid hydrolysis by KPC-2 β-lactamase.
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Affiliation(s)
- Shrenik C Mehta
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Ian M Furey
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Orville A Pemberton
- Department of Molecular Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida, USA
| | - David M Boragine
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Yu Chen
- Department of Molecular Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida, USA
| | - Timothy Palzkill
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas, USA.
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Galbadage T, Liu D, Alemany LB, Pal R, Tour JM, Gunasekera RS, Cirillo JD. Molecular Nanomachines Disrupt Bacterial Cell Wall, Increasing Sensitivity of Extensively Drug-Resistant Klebsiella pneumoniae to Meropenem. ACS Nano 2019; 13:14377-14387. [PMID: 31815423 PMCID: PMC6933815 DOI: 10.1021/acsnano.9b07836] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 12/09/2019] [Indexed: 05/22/2023]
Abstract
Multidrug resistance in pathogenic bacteria is an increasing problem in patient care and public health. Molecular nanomachines (MNMs) have the ability to open cell membranes using nanomechanical action. We hypothesized that MNMs could be used as antibacterial agents by drilling into bacterial cell walls and increasing susceptibility of drug-resistant bacteria to recently ineffective antibiotics. We exposed extensively drug-resistant Klebsiella pneumoniae to light-activated MNMs and found that MNMs increase the susceptibility to Meropenem. MNMs with Meropenem can effectively kill K. pneumoniae that are considered Meropenem-resistant. We examined the mechanisms of MNM action using permeability assays and transmission electron microscopy, finding that MNMs disrupt the cell wall of extensively drug-resistant K. pneumoniae, exposing the bacteria to Meropenem. These observations suggest that MNMs could be used to make conventional antibiotics more efficacious against multi-drug-resistant pathogens.
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Affiliation(s)
- Thushara Galbadage
- Department of Microbial
Pathogenesis and Immunology, Texas A&M
Health Science Center, Bryan, Texas 77807, United States
| | - Dongdong Liu
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
| | - Lawrence B. Alemany
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
| | - Robert Pal
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - James M. Tour
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
- E-mail:
| | - Richard S. Gunasekera
- Department of Chemistry, Department of Materials
Science and NanoEngineering, Smalley-Curl Institute, NanoCarbon Center, Department of BioSciences, and Shared Equipment
Authority, Rice University, Houston, Texas 77005, United States
- Department Biological Science, Biola University, La Mirada, California 90639, United States
- E-mail:
| | - Jeffrey D. Cirillo
- Department of Microbial
Pathogenesis and Immunology, Texas A&M
Health Science Center, Bryan, Texas 77807, United States
- E-mail:
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4
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Kidd JM, Abdelraouf K, Nicolau DP. Development of Neutropenic Murine Models of Iron Overload and Depletion To Study the Efficacy of Siderophore-Antibiotic Conjugates. Antimicrob Agents Chemother 2019; 64:e01961-19. [PMID: 31658967 PMCID: PMC7187605 DOI: 10.1128/aac.01961-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 10/20/2019] [Indexed: 02/07/2023] Open
Abstract
Siderophore-antibiotic conjugates have increased in vitro activity in low-iron environments where bacteria express siderophores and associated transporters. The host immune hypoferremic response reduces iron availability to bacteria; however, patients with iron overload or deficiency may have altered ability to restrict iron, which may affect the efficacy of siderophore-antibiotic conjugates. In vivo models of infection with iron overload and deficiency are needed to perform this assessment. The standard neutropenic murine thigh infection model was supplemented with iron-altering treatments: iron dextran at 100 mg/kg of body weight daily for 14 days to load iron or deferoxamine at 100 mg/kg daily plus a low-iron diet for up to 30 days to deplete iron. Human-simulated regimens of cefiderocol and meropenem were administered in both models to assess any impact of iron alteration on plasma pharmacokinetics. Median iron in overloaded mice was significantly higher than that of controls in plasma (1,657 versus 336 μg/dl; P < 0.001), liver (2,133 versus 11 μg/g; P < 0.001), and spleen (473 versus 144 μg/g; P < 0.001). At 30 days, depleted mice had significantly lower iron than controls in liver (2.4 versus 6.5 μg/g; P < 0.001) and spleen (72 versus 133 μg/g; P = 0.029) but not plasma (351 versus 324 μg/dl; P = 0.95). Cefiderocol and meropenem plasma concentrations were similar in iron overloaded and control mice but varied in iron-depleted mice. The iron-overloaded murine thigh infection model was established, and human-simulated regimens of cefiderocol and meropenem were validated therein. While deferoxamine successfully reduced liver and splenic iron, this depleting treatment altered the pharmacokinetics of both antimicrobials.
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Affiliation(s)
- James M Kidd
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, Connecticut, USA
| | - Kamilia Abdelraouf
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, Connecticut, USA
| | - David P Nicolau
- Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, Connecticut, USA
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5
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Papp-Wallace KM. The latest advances in β-lactam/β-lactamase inhibitor combinations for the treatment of Gram-negative bacterial infections. Expert Opin Pharmacother 2019; 20:2169-2184. [PMID: 31500471 PMCID: PMC6834881 DOI: 10.1080/14656566.2019.1660772] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/23/2019] [Indexed: 12/21/2022]
Abstract
Introduction: Antimicrobial resistance in Gram-negative pathogens is a significant threat to global health. β-Lactams (BL) are one of the safest and most-prescribed classes of antibiotics on the market today. The acquisition of β-lactamases, especially those which hydrolyze carbapenems, is eroding the efficacy of BLs for the treatment of serious infections. During the past decade, significant advances were made in the development of novel BL-β-lactamase inhibitor (BLI) combinations to target β-lactamase-mediated resistant Gram-negatives.Areas covered: The latest progress in 20 different approved, developing, and preclinical BL-BLI combinations to target serine β-lactamases produced by Gram-negatives are reviewed based on primary literature, conference abstracts (when available), and US clinical trial searches within the last 5 years. The majority of the compounds that are discussed are being evaluated as part of a BL-BLI combination.Expert opinion: The current trajectory in BLI development is promising; however, a significant challenge resides in the selection of an appropriate BL partner as well as the development of resistance linked to the BL partner. In addition, dosing regimens for these BL-BLI combinations need to be critically evaluated. A revolution in bacterial diagnostics is essential to aid clinicians in the appropriate selection of novel BL-BLI combinations for the treatment of serious infections.
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Affiliation(s)
- Krisztina M. Papp-Wallace
- Louis Stokes Cleveland Department of Veterans Affairs, Research Service, Cleveland, OH, USA
- Department of Medicine, Case Western Reserve University, Cleveland, OH, USA
- Department of Biochemistry, Case Western Reserve University, Cleveland, OH, USA
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6
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Stewart NK, Smith CA, Antunes NT, Toth M, Vakulenko SB. Role of the Hydrophobic Bridge in the Carbapenemase Activity of Class D β-Lactamases. Antimicrob Agents Chemother 2019; 63:e02191-18. [PMID: 30530607 PMCID: PMC6355612 DOI: 10.1128/aac.02191-18] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 11/29/2018] [Indexed: 01/25/2023] Open
Abstract
Class D carbapenemases are enzymes of the utmost clinical importance due to their ability to confer resistance to the last-resort carbapenem antibiotics. We investigated the role of the conserved hydrophobic bridge in the carbapenemase activity of OXA-23, the major carbapenemase of the important pathogen Acinetobacter baumannii We show that substitution of the bridge residue Phe110 affects resistance to meropenem and doripenem and has little effect on MICs of imipenem. The opposite effect was observed upon substitution of the other bridge residue Met221. Complete disruption of the bridge by the F110A/M221A substitution resulted in a significant loss of affinity for doripenem and meropenem and to a lesser extent for imipenem, which is reflected in the reduced MICs of these antibiotics. In the wild-type OXA-23, the pyrrolidine ring of the meropenem tail forms a hydrophobic interaction with Phe110 of the bridge. Similar interactions would ensue with ring-containing doripenem but not with imipenem, which lacks this ring. Our structural studies showed that this interaction with the meropenem tail is missing in the F110A/M221A mutant. These data explain why disruption of the interaction between the enzyme and the carbapenem substrate impacts the affinity and MICs of meropenem and doripenem to a larger degree than those of imipenem. Our structures also show that the bridge directs the acylated carbapenem into a specific tautomeric conformation. However, it is not this conformation but rather the stabilizing interaction between the tail of the antibiotic and the hydrophobic bridge that contributes to the carbapenemase activity of class D β-lactamases.
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Affiliation(s)
- Nichole K Stewart
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Clyde A Smith
- Stanford Synchrotron Radiation Lightsource, Stanford University, Menlo Park, California, USA
| | - Nuno T Antunes
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Marta Toth
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Sergei B Vakulenko
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
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Salimraj R, Hinchliffe P, Kosmopoulou M, Tyrrell JM, Brem J, van Berkel SS, Verma A, Owens RJ, McDonough MA, Walsh TR, Schofield CJ, Spencer J. Crystal structures of VIM-1 complexes explain active site heterogeneity in VIM-class metallo-β-lactamases. FEBS J 2019; 286:169-183. [PMID: 30430727 PMCID: PMC6326847 DOI: 10.1111/febs.14695] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 10/06/2018] [Accepted: 11/02/2018] [Indexed: 12/12/2022]
Abstract
Metallo-β-Lactamases (MBLs) protect bacteria from almost all β-lactam antibiotics. Verona integron-encoded MBL (VIM) enzymes are among the most clinically important MBLs, with VIM-1 increasing in carbapenem-resistant Enterobacteriaceae (Escherichia coli, Klebsiella pneumoniae) that are among the hardest bacterial pathogens to treat. VIM enzymes display sequence variation at residues (224 and 228) that in related MBLs are conserved and participate in substrate binding. How they accommodate this variability, while retaining catalytic efficiency against a broad substrate range, has remained unclear. Here, we present crystal structures of VIM-1 and its complexes with a substrate-mimicking thioenolate inhibitor, ML302F, that restores meropenem activity against a range of VIM-1 producing clinical strains, and the hydrolysed product of the carbapenem meropenem. Comparison of these two structures identifies a water-mediated hydrogen bond, between the carboxylate group of substrate/inhibitor and the backbone carbonyl of the active site zinc ligand Cys221, that is common to both complexes. Structural comparisons show that the responsible Cys221-bound water is observed in all known VIM structures, participates in carboxylate binding with other inhibitor classes, and thus effectively replicates the role of the conserved Lys224 in analogous complexes with other MBLs. These results provide a mechanism for substrate binding that permits the variation at positions 224 and 228 that is a hallmark of VIM MBLs. ENZYMES: EC 3.5.2.6 DATABASES: Co-ordinates and structure factors for protein structures described in this manuscript have been deposited in the Protein Data Bank (www.rcsb.org/pdb) with accession codes 5N5G (VIM-1), 5N5H (VIM-1:ML302F complex) and 5N5I (VIM-1-hydrolysed meropenem complex).
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Affiliation(s)
- Ramya Salimraj
- School of Cellular and Molecular MedicineUniversity of BristolUK
| | | | | | | | - Jürgen Brem
- Department of ChemistryUniversity of OxfordUK
| | | | - Anil Verma
- Oxford Protein Production Facility UKRutherford Appleton LaboratoryOxfordshireUK
| | - Raymond J. Owens
- Oxford Protein Production Facility UKRutherford Appleton LaboratoryOxfordshireUK
| | | | | | | | - James Spencer
- School of Cellular and Molecular MedicineUniversity of BristolUK
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8
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Božić B, Korać J, Stanković DM, Stanić M, Romanović M, Pristov JB, Spasić S, Popović-Bijelić A, Spasojević I, Bajčetić M. Coordination and redox interactions of β-lactam antibiotics with Cu 2+ in physiological settings and the impact on antibacterial activity. Free Radic Biol Med 2018; 129:279-285. [PMID: 30267756 DOI: 10.1016/j.freeradbiomed.2018.09.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 09/17/2018] [Accepted: 09/23/2018] [Indexed: 11/22/2022]
Abstract
An increase in the copper pool in body fluids has been related to a number of pathological conditions, including infections. Copper ions may affect antibiotics via the formation of coordination bonds and/or redox reactions. Herein, we analyzed the interactions of Cu2+ with eight β-lactam antibiotics using UV-Vis spectrophotometry, EPR spectroscopy, and electrochemical methods. Penicillin G did not show any detectable interactions with Cu2+. Ampicillin, amoxicillin and cephalexin formed stable colored complexes with octahedral coordination environment of Cu2+ with tetragonal distortion, and primary amine group as the site of coordinate bond formation. These β-lactams increased the solubility of Cu2+ in the phosphate buffer. Ceftazidime and Cu2+ formed a complex with a similar geometry and gave rise to an organic radical. Ceftriaxone-Cu2+ complex appears to exhibit different geometry. All complexes showed 1:1 stoichiometry. Cefaclor reduced Cu2+ to Cu1+ that further reacted with molecular oxygen to produce hydrogen peroxide. Finally, meropenem underwent degradation in the presence of copper. The analysis of activity against Escherichia coli and Staphylococcus aureus showed that the effects of meropenem, amoxicillin, ampicillin, and ceftriaxone were significantly hindered in the presence of copper ions. The interactions with copper ions should be taken into account regarding the problem of antibiotic resistance and in the selection of the most efficient antimicrobial therapy for patients with altered copper homeostasis.
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Affiliation(s)
- Bojana Božić
- Department of Pharmacology, Clinical Pharmacology and Toxicology, School of Medicine, University of Belgrade, P.O. Box 38, 11000 Belgrade, Serbia
| | - Jelena Korać
- Life Sciences Department, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11000 Belgrade, Serbia
| | - Dalibor M Stanković
- The Vinča Institute of Nuclear Sciences, University of Belgrade, POB 522, 11001 Belgrade, Serbia; Innovation Center of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade 11000, Serbia
| | - Marina Stanić
- Life Sciences Department, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11000 Belgrade, Serbia
| | - Mima Romanović
- Life Sciences Department, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11000 Belgrade, Serbia
| | - Jelena Bogdanović Pristov
- Life Sciences Department, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11000 Belgrade, Serbia
| | - Snežana Spasić
- Innovation Center of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade 11000, Serbia
| | - Ana Popović-Bijelić
- EPR Laboratory, Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11158 Belgrade, Serbia
| | - Ivan Spasojević
- Life Sciences Department, Institute for Multidisciplinary Research, University of Belgrade, Kneza Višeslava 1, 11000 Belgrade, Serbia.
| | - Milica Bajčetić
- Department of Pharmacology, Clinical Pharmacology and Toxicology, School of Medicine, University of Belgrade, P.O. Box 38, 11000 Belgrade, Serbia; Clinical Pharmacology Unit, University Children's Hospital, 11000 Belgrade, Serbia
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Kilińska K, Cielecka-Piontek J, Skibiński R, Szymanowska D, Miklaszewski A, Bednarski W, Tykarska E, Stasiłowicz A, Zalewski P. The Radiostability of Meropenem Trihydrate in Solid State. Molecules 2018; 23:molecules23112738. [PMID: 30360551 PMCID: PMC6278425 DOI: 10.3390/molecules23112738] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/18/2018] [Accepted: 10/22/2018] [Indexed: 11/16/2022] Open
Abstract
The influence of ionising radiation on the physicochemical properties of meropenem trihydrate in solid state was studied for doses of e-beam radiation: 25 kGy and 400 kGy. In the first part of our studies, we evaluated the possibility of applying radiosterilization to obtain sterile meropenem. No changes for meropenem irradiated with a dose of 25 kGy, the dose required to attain sterility, was confirmed in the results of spectroscopic (FT-IR), thermal (DSC, TGA) and X-ray powder diffraction (XRPD) studies. The radiation dose of 25 kGy produces no more than about 1500 ppm of radical defects. The chromatographic studies of irradiated meropenem in solutions did not show any chemical degradation. Moreover, the antimicrobial activity of meropenem irradiated with the dose of 25 kGy was unchanged. Based on the received results, we can conclude that radiostelization is a promising, alternative method for obtaining sterile meropenem. In the second part of the research, meropenem was exposed to e-beam radiation at the 400 kGy dose rate. It was confirmed, that reducing of antimicrobial activity could be connected with the degradation of β-lactam ring and changes in the trans-hydroxyethyl group. Apart from chemical changes, changes in the physical stability of irradiated meropenem (400 kGy) was also observed.
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Affiliation(s)
- Karolina Kilińska
- Department of Pharmacognosy, Poznan University of Medical Sciences, Święcickiego 4, 60-781 Poznań, Poland.
| | - Judyta Cielecka-Piontek
- Department of Pharmacognosy, Poznan University of Medical Sciences, Święcickiego 4, 60-781 Poznań, Poland.
| | - Robert Skibiński
- Department of Medicinal Chemistry, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland.
| | - Daria Szymanowska
- Department of Biotechnology and Food Microbiology, Poznań University of Life Sciences, Wojska Polskiego 48, 60-627 Poznań, Poland.
| | - Andrzej Miklaszewski
- Institute of Material Science and Engineering, Poznan University of Technology, Jana Pawła II 24, 60-965 Poznań, Poland.
| | - Waldemar Bednarski
- Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Poznań, Poland.
| | - Ewa Tykarska
- Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan, Poland.
| | - Anna Stasiłowicz
- Department of Pharmacognosy, Poznan University of Medical Sciences, Święcickiego 4, 60-781 Poznań, Poland.
| | - Przemysław Zalewski
- Department of Pharmacognosy, Poznan University of Medical Sciences, Święcickiego 4, 60-781 Poznań, Poland.
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10
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Abstract
OBJECTIVE To review the pharmacology, spectrum of activity, pharmacokinetics, pharmacodynamics, safety, efficacy, administration, and considerations for clinical use of meropenem/vaborbactam (M/V). DATA SOURCES A literature search using PubMed and clinicaltrials.gov (June 2013 to December 2017) was conducted using the search terms meropenem, vaborbactam, RPX7009, biapenem, RPX2003, and carbavance. References from relevant articles and conference abstracts were also reviewed. STUDY SELECTION AND DATA EXTRACTION Preclinical, phase I studies, and phase III studies written in the English language were evaluated. DATA SYNTHESIS M/V is a novel carbapenem/β-lactamase inhibitor antimicrobial with in vitro activity against nearly 99% of Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae. M/V is approved for the treatment of adults with complicated urinary tract infections (cUTIs), including pyelonephritis. In a phase III cUTI trial (TANGO I), 98.4% of patients treated with M/V experienced overall clinical success compared with 94% of patients treated with piperacillin/tazobactam (95% CI = 0.7 to 9.1). When compared with best available therapy for carbapenem-resistant Enterobacteriaceae (CRE) infections in TANGO II, patients receiving M/V were more likely to achieve clinical cure at both the end of therapy (64.3% vs 33.3%, P = 0.04) as well as at the test of cure (57.1% vs 26.7%, P = 0.04). The most common adverse effects associated with M/V were headache, infusion-site reactions, and diarrhea. CONCLUSION M/V has a valuable role in the treatment of CRE and should be used judiciously to preserve its use for resistant infections.
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Affiliation(s)
| | | | | | - Joe Pardo
- 4 North Florida/South Georgia Veterans Health System, Gainesville, FL, USA
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