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Kubitschke M, Masseck OA. Illuminating the brain-genetically encoded single wavelength fluorescent biosensors to unravel neurotransmitter dynamics. Biol Chem 2024; 405:55-65. [PMID: 37246368 DOI: 10.1515/hsz-2023-0175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/15/2023] [Indexed: 05/30/2023]
Abstract
Understanding how neuronal networks generate complex behavior is one of the major goals of Neuroscience. Neurotransmitter and Neuromodulators are crucial for information flow between neurons and understanding their dynamics is the key to unravel their role in behavior. To understand how the brain transmits information and how brain states arise, it is essential to visualize the dynamics of neurotransmitters, neuromodulators and neurochemicals. In the last five years, an increasing number of single-wavelength biosensors either based on periplasmic binding proteins (PBPs) or on G-protein-coupled receptors (GPCR) have been published that are able to detect neurotransmitter release in vitro and in vivo with high spatial and temporal resolution. Here we review and discuss recent progress in the development of these sensors, their limitations and future directions.
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Conti P, Lazzaro LM, Longo F, Lenzo F, Giardina A, Fortuna SA, Stefani S, Campanile F. Unveiling the Relationship between Ceftobiprole and High-Molecular-Mass (HMM) Penicillin-Binding Proteins ( PBPs) in Enterococcus faecalis. Antibiotics (Basel) 2024; 13:65. [PMID: 38247624 PMCID: PMC10812503 DOI: 10.3390/antibiotics13010065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 12/30/2023] [Accepted: 01/06/2024] [Indexed: 01/23/2024] Open
Abstract
Low-affinity PBP4, historically linked to penicillin resistance in Enterococcus faecalis, may still have affinity for novel cephalosporins. Ceftobiprole (BPR) is a common therapeutic choice, even with PBP4-related overexpression and amino acid substitution due to mutations. Our study aims to explore the interaction between BPR and High-Molecular-Mass (HMM) low-reactive PBPs in Penicillin-Resistant-Ampicillin-Susceptible/Ceftobiprole Non-Susceptible (PRAS/BPR-NS) E. faecalis clinical isolates. We conducted competition assays examining class A and B HMM PBPs from four PRAS/BPR-NS E. faecalis strains using purified membrane proteins and fluorescent penicillin (Bocillin FL), in treated and untreated conditions. Interaction strength was assessed calculating the 50% inhibitory concentration (IC50) values for ceftobiprole, by analyzing fluorescence intensity trends. Due to its low affinity, PBP4 did not display significant acylation among all strains. Moreover, both PBP1a and PBP1b showed a similar insensitivity trend. Conversely, other PBPs showed IC50 values ranging from 1/2-fold to 4-fold MICs. Upon higher BPR concentrations, increased percentages of PBP4 inhibition were observed in all strains. Our results support the hypothesis that PBP4 is necessary but not sufficient for BPR resistance, changing the paradigm for enterococcal cephalosporin resistance. We hypothesize that cooperation between class B PBP4 and at least one bifunctional class A PBP could be required to synthesize peptidoglycan and promote growth.
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Affiliation(s)
- Paola Conti
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy
| | - Lorenzo Mattia Lazzaro
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
| | - Fabio Longo
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
- Department of Public Health and Pediatrics, University of Torino, 10126 Turin, Italy
| | - Federica Lenzo
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
| | - Alessandra Giardina
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
| | - Sebastiano Alberto Fortuna
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
| | - Stefania Stefani
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
| | - Floriana Campanile
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Section of Microbiology, University of Catania, 95123 Catania, Italy; (P.C.); (L.M.L.); (F.L.); (F.L.); (A.G.); (S.A.F.); (S.S.)
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Giuliano S, Angelini J, D'Elia D, Geminiani M, Barison RD, Giacinta A, Sartor A, Campanile F, Curcio F, Cotta MO, Roberts JA, Baraldo M, Tascini C. Ampicillin and Ceftobiprole Combination for the Treatment of Enterococcus faecalis Invasive Infections: "The Times They Are A-Changin". Antibiotics (Basel) 2023; 12:antibiotics12050879. [PMID: 37237782 DOI: 10.3390/antibiotics12050879] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/23/2023] [Accepted: 05/04/2023] [Indexed: 05/28/2023] Open
Abstract
BACKGROUND Enterococcus faecalis is responsible for a large variety of severe infections. This study is a case series reporting our experience in the treatment of E. faecalis invasive infections with ampicillin in combination with ceftobiprole (ABPR). METHODS We retrospectively analyzed all the medical records of patients admitted to the University Hospital of Udine from January to December 2020 with a diagnosis of infective endocarditis or primary or non-primary complicated or uncomplicated bacteremia caused by E. faecalis. RESULTS Twenty-one patients were included in the final analysis. The clinical success rate was very high, accounting for 81% of patients, and microbiological cure was obtained in 86% of patients. One relapse was recorded in one patient who did not adhere to the partial oral treatment prescribed. Therapeutic drug monitoring (TDM) was always performed for ampicillin and ceftobiprole, and serum concentrations of both drugs were compared to the MICs of the different enterococcal isolates. CONCLUSIONS ABPR is a well-tolerated antimicrobial regimen with anti-E. faecalis activity. TDM can help clinicians optimize medical treatments to achieve the best possible efficacy with fewer side effects. ABPR might be a reasonable option for the treatment of severe invasive infections caused by E. faecalis due to the high level of enterococcal penicillin-binding protein (PBP) saturation.
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Affiliation(s)
- Simone Giuliano
- Infectious Diseases Division, Department of Medicine, University of Udine and Azienda Sanitaria Universitaria Friuli Centrale, 33100 Udine, Italy
| | - Jacopo Angelini
- Clinical Pharmacology and Toxicology Institute, University Hospital Friuli Centrale ASUFC, 33100 Udine, Italy
- Department of Medicine, University of Udine (UNIUD), 33100 Udine, Italy
| | - Denise D'Elia
- Infectious Diseases Division, Department of Medicine, University of Udine and Azienda Sanitaria Universitaria Friuli Centrale, 33100 Udine, Italy
| | - Monica Geminiani
- Infectious Diseases Division, Department of Medicine, University of Udine and Azienda Sanitaria Universitaria Friuli Centrale, 33100 Udine, Italy
| | - Roberto Daniele Barison
- Infectious Diseases Division, Department of Medicine, University of Udine and Azienda Sanitaria Universitaria Friuli Centrale, 33100 Udine, Italy
| | - Alessandro Giacinta
- Infectious Diseases Division, Department of Medicine, University of Udine and Azienda Sanitaria Universitaria Friuli Centrale, 33100 Udine, Italy
| | - Assunta Sartor
- Microbiology Unit, Udine University Hospital, 33100 Udine, Italy
| | - Floriana Campanile
- Department of Biomedical and Biotechnological Sciences, Section of Microbiology, University of Catania, 95123 Catania, Italy
| | - Francesco Curcio
- Department of Medicine, University of Udine (UNIUD), 33100 Udine, Italy
- Institute of Clinical Pathology, Azienda Sanitaria Universitaria Friuli Centrale (ASUFC), 33100 Udine, Italy
| | - Menino Osbert Cotta
- Faculty of Medicine, University of Queensland, Centre for Clinical Research (UQCCR), Brisbane, QLD 4029, Australia
- Herston Infectious Diseases Institute, Herston, QLD 4029, Australia
| | - Jason A Roberts
- Faculty of Medicine, University of Queensland, Centre for Clinical Research (UQCCR), Brisbane, QLD 4029, Australia
- Herston Infectious Diseases Institute, Herston, QLD 4029, Australia
- Departments of Intensive Care Medicine and Pharmacy, Royal Brisbane and Women's Hospital, Brisbane, QLD 4029, Australia
- Division of Anaesthesiology Critical Care Emergency and Pain Medicine, Nîmes University Hospital, University of Montpellier, 34095 Nîmes, France
| | - Massimo Baraldo
- Clinical Pharmacology and Toxicology Institute, University Hospital Friuli Centrale ASUFC, 33100 Udine, Italy
- Department of Medicine, University of Udine (UNIUD), 33100 Udine, Italy
| | - Carlo Tascini
- Infectious Diseases Division, Department of Medicine, University of Udine and Azienda Sanitaria Universitaria Friuli Centrale, 33100 Udine, Italy
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Dingle KE, Freeman J, Didelot X, Quan TP, Eyre DW, Swann J, Spittal WD, Clark EV, Jolley KA, Walker AS, Wilcox MH, Crook DW. Penicillin Binding Protein Substitutions Cooccur with Fluoroquinolone Resistance in Epidemic Lineages of Multidrug-Resistant Clostridioides difficile. mBio 2023; 14:e0024323. [PMID: 37017518 PMCID: PMC10128037 DOI: 10.1128/mbio.00243-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2023] Open
Abstract
Clostridioides difficile remains a key cause of healthcare-associated infection, with multidrug-resistant (MDR) lineages causing high-mortality (≥20%) outbreaks. Cephalosporin treatment is a long-established risk factor, and antimicrobial stewardship is a key control. A mechanism underlying raised cephalosporin MICs has not been identified in C. difficile, but among other species, this is often acquired via amino acid substitutions in cell wall transpeptidases (penicillin binding proteins [PBPs]). Here, we investigated five C. difficile transpeptidases (PBP1 to PBP5) for recent substitutions, associated cephalosporin MICs, and co-occurrence with fluoroquinolone resistance. Previously published genome assemblies (n = 7,096) were obtained, representing 16 geographically widespread lineages, including healthcare-associated ST1(027). Recent amino acid substitutions were found within PBP1 (n = 50) and PBP3 (n = 48), ranging from 1 to 10 substitutions per genome. β-Lactam MICs were measured for closely related pairs of wild-type and PBP-substituted isolates separated by 20 to 273 single nucleotide polymorphisms (SNPs). Recombination-corrected phylogenies were constructed to date substitution acquisition. Key substitutions such as PBP3 V497L and PBP1 T674I/N/V emerged independently across multiple lineages. They were associated with extremely high cephalosporin MICs; 1 to 4 doubling dilutions >wild-type, up to 1,506 μg/mL. Substitution patterns varied by lineage and clade, showed geographic structure, and occurred post-1990, coincident with the gyrA and/or gyrB substitutions conferring fluoroquinolone resistance. In conclusion, recent PBP1 and PBP3 substitutions are associated with raised cephalosporin MICs in C. difficile. Their co-occurrence with fluoroquinolone resistance hinders attempts to understand the relative importance of these drugs in the dissemination of epidemic lineages. Further controlled studies of cephalosporin and fluoroquinolone stewardship are needed to determine their relative effectiveness in outbreak control. IMPORTANCE Fluoroquinolone and cephalosporin use in healthcare settings has triggered outbreaks of high-mortality, multidrug-resistant C. difficile infection. Here, we identify a mechanism associated with raised cephalosporin MICs in C. difficile comprising amino acid substitutions in two cell wall transpeptidase enzymes (penicillin binding proteins). The higher the number of substitutions, the greater the impact on phenotype. Dated phylogenies revealed that substitutions associated with raised cephalosporin and fluoroquinolone MICs were co-acquired immediately before clinically important outbreak strains emerged. PBP substitutions were geographically structured within genetic lineages, suggesting adaptation to local antimicrobial prescribing. Antimicrobial stewardship of cephalosporins and fluoroquinolones is an effective means of C. difficile outbreak control. Genetic changes associated with raised MIC may impart a "fitness cost" after antibiotic withdrawal. Our study therefore identifies a mechanism that may explain the contribution of cephalosporin stewardship to resolving outbreak conditions. However, due to the co-occurrence of raised cephalosporin MICs and fluoroquinolone resistance, further work is needed to determine the relative importance of each.
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Affiliation(s)
- Kate E Dingle
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - Jane Freeman
- Department of Microbiology, Leeds Teaching Hospitals Trust, Leeds, United Kingdom
- Healthcare Associated Infections Research Group, The Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom
| | - Xavier Didelot
- School of Life Sciences and Department of Statistics, University of Warwick, Coventry, United Kingdom
| | - T Phuong Quan
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - David W Eyre
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
- Big Data Institute, Nuffield Department of Population Health, Oxford University of Oxford, Oxford, United Kingdom
| | - Jeremy Swann
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - William D Spittal
- Department of Microbiology, Leeds Teaching Hospitals Trust, Leeds, United Kingdom
- Healthcare Associated Infections Research Group, The Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom
| | - Emma V Clark
- Department of Microbiology, Leeds Teaching Hospitals Trust, Leeds, United Kingdom
- Healthcare Associated Infections Research Group, The Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom
| | - Keith A Jolley
- Department of Biology, University of Oxford, Oxford, United Kingdom
| | - A Sarah Walker
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - Mark H Wilcox
- Department of Microbiology, Leeds Teaching Hospitals Trust, Leeds, United Kingdom
- Healthcare Associated Infections Research Group, The Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom
| | - Derrick W Crook
- Nuffield Department of Clinical Medicine, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom
- National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, United Kingdom
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Chen X, Bai K, Lyu Q, Jiang N, Li J, Luo L. Role of Penicillin-Binding Proteins in the Viability, Morphology, Stress Tolerance, and Pathogenicity of Clavibacter michiganensis. Phytopathology 2021; 111:1301-1312. [PMID: 33369478 DOI: 10.1094/phyto-08-20-0326-r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Previous research has shown that penicillin-binding proteins (PBPs), enzymes involved in peptidoglycan (PG) assembly, could play an important role during the induction of the viable but nonculturable (VBNC) state, which allows non-spore-forming bacteria to survive adverse environmental conditions. The current study found that Clavibacter michiganensis has seven PBPs. Mutant analysis indicated that deletion of either of the class B PBPs was lethal and that the class A PBPs had an important role in PG synthesis, with the ΔpbpC mutant having an altered cellular morphology that resulted in longer cells that were swollen at one end and had thinner cell walls. The ΔpbpC mutant was also found to produce mucoid colonies in solid culture and a lower final cell titer in liquid medium, as well as having high sensitivity to osmotic stress and lysozyme treatment and surprisingly high pathogenicity. The double mutant, ΔdacB/ΔpbpE, also had a slightly altered phenotype, resulting in longer cells. Further analysis revealed that both mutants had high sensitivity to copper, which resulted in quicker induction into the VBNC state. However, only the ΔpbpC mutant had significantly reduced survivorship in the VBNC state. The study also confirmed that the VBNC state significantly improved the survivorship of wild-type C. michiganensis cells in response to environmental stresses and systemically demonstrated the protective role of the VBNC state in C. michiganensis, which is an important finding regarding its epidemiology and has serious implications for disease management.
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Affiliation(s)
- Xing Chen
- Department of Plant Pathology, College of Plant Protection, China Agricultural University; Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, P.R. China
| | - Kaihong Bai
- Department of Plant Pathology, College of Plant Protection, China Agricultural University; Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, P.R. China
| | - Qingyang Lyu
- Department of Plant Pathology, College of Plant Protection, China Agricultural University; Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, P.R. China
- Key Laboratory of Environmental and Applied Microbiology, CAS, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, P.R. China
| | - Na Jiang
- Department of Plant Pathology, College of Plant Protection, China Agricultural University; Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, P.R. China
| | - Jianqiang Li
- Department of Plant Pathology, College of Plant Protection, China Agricultural University; Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, P.R. China
| | - Laixin Luo
- Department of Plant Pathology, College of Plant Protection, China Agricultural University; Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, P.R. China
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López-Pérez A, Freischem S, Grimm I, Weiergräber O, Dingley AJ, López-Alberca MP, Waldmann H, Vollmer W, Kumar K, Vuong C. Discovery of Pyrrolidine-2,3-diones as Novel Inhibitors of P. aeruginosa PBP3. Antibiotics (Basel) 2021; 10:529. [PMID: 34064358 DOI: 10.3390/antibiotics10050529] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 04/30/2021] [Accepted: 05/03/2021] [Indexed: 12/01/2022] Open
Abstract
The alarming threat of the spread of multidrug resistant bacteria currently leaves clinicians with very limited options to combat infections, especially those from Gram-negative bacteria. Hence, innovative strategies to deliver the next generation of antibacterials are urgently needed. Penicillin binding proteins (PBPs) are proven targets inhibited by β-lactam antibiotics. To discover novel, non-β-lactam inhibitors against PBP3 of Pseudomonas aeruginosa, we optimised a fluorescence assay based on a well-known thioester artificial substrate and performed a target screening using a focused protease-targeted library of 2455 compounds, which led to the identification of pyrrolidine-2,3-dione as a potential scaffold to inhibit the PBP3 target. Further chemical optimisation using a one-pot three-component reaction protocol delivered compounds with excellent target inhibition, initial antibacterial activities against P. aeruginosa and no apparent cytotoxicity. Our investigation revealed the key structural features; for instance, 3-hydroxyl group (R2) and a heteroaryl group (R1) appended to the N-pyrroldine-2,3-dione via methylene linker required for target inhibition. Overall, the discovery of the pyrrolidine-2,3-dione class of inhibitors of PBP3 brings opportunities to target multidrug-resistant bacterial strains and calls for further optimisation to improve antibacterial activity against P. aeruginosa.
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Abstract
The peptidoglycan sacculus is a net-like polymer that surrounds the cytoplasmic membrane in most bacteria. It is essential to maintain the bacterial cell shape and protect from turgor. The peptidoglycan has a basic composition, common to all bacteria, with species-specific variations that can modify its biophysical properties or the pathogenicity of the bacteria. The synthesis of peptidoglycan starts in the cytoplasm and the precursor lipid II is flipped across the cytoplasmic membrane. The new peptidoglycan strands are synthesised and incorporated into the pre-existing sacculus by the coordinated activities of peptidoglycan synthases and hydrolases. In the model organism Escherichia coli there are two complexes required for the elongation and division. Each of them is regulated by different proteins from both the cytoplasmic and periplasmic sides that ensure the well-coordinated synthesis of new peptidoglycan.
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Ceballos S, Kim C, Ding D, Mobashery S, Chang M, Torres C. Activities of Oxadiazole Antibacterials against Staphylococcus aureus and Other Gram-Positive Bacteria. Antimicrob Agents Chemother 2018; 62:e00453-18. [PMID: 29866865 PMCID: PMC6105842 DOI: 10.1128/aac.00453-18] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/26/2018] [Indexed: 12/13/2022] Open
Abstract
The activities of four oxadiazoles were investigated with 210 methicillin-resistant Staphylococcus aureus (MRSA) strains. MIC50 and MIC90 values of 1 to 2 and 4 μg/ml, respectively, were observed. We also evaluated the activity of oxadiazole ND-421 against other staphylococci and enterococci and in the presence of oxacillin for selected MRSA strains. The MIC for ND-421 is lowered severalfold in combination with oxacillin, as they synergize. The MIC90 of ND-421 against vancomycin-resistant enterococci is ≤1 μg/ml.
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Affiliation(s)
- Sara Ceballos
- Area of Biochemistry and Molecular Biology, University of La Rioja, Logroño, Spain
| | - Choon Kim
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Derong Ding
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Mayland Chang
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Carmen Torres
- Area of Biochemistry and Molecular Biology, University of La Rioja, Logroño, Spain
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Sutaria DS, Moya B, Green KB, Kim TH, Tao X, Jiao Y, Louie A, Drusano GL, Bulitta JB. First Penicillin-Binding Protein Occupancy Patterns of β-Lactams and β-Lactamase Inhibitors in Klebsiella pneumoniae. Antimicrob Agents Chemother 2018; 62:e00282-18. [PMID: 29712652 PMCID: PMC5971569 DOI: 10.1128/aac.00282-18] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [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: 02/10/2018] [Accepted: 02/28/2018] [Indexed: 01/22/2023] Open
Abstract
Penicillin-binding proteins (PBPs) are the high-affinity target sites of all β-lactam antibiotics in bacteria. It is well known that each β-lactam covalently binds to and thereby inactivates different PBPs with various affinities. Despite β-lactams serving as the cornerstone of our therapeutic armamentarium against Klebsiella pneumoniae, PBP binding data are missing for this pathogen. We aimed to generate the first PBP binding data on 13 chemically diverse and clinically relevant β-lactams and β-lactamase inhibitors in K. pneumoniae PBP binding was determined using isolated membrane fractions from K. pneumoniae strains ATCC 43816 and ATCC 13883. Binding reactions were conducted using β-lactam concentrations from 0.0075 to 256 mg/liter (or 128 mg/liter). After β-lactam exposure, unbound PBPs were labeled by Bocillin FL. Binding affinities (50% inhibitory concentrations [IC50]) were reported as the β-lactam concentrations that half-maximally inhibited Bocillin FL binding. PBP occupancy patterns by β-lactams were consistent across both strains. Carbapenems bound to all PBPs, with PBP2 and PBP4 as the highest-affinity targets (IC50, <0.0075 mg/liter). Preferential PBP2 binding was observed by mecillinam (amdinocillin; IC50, <0.0075 mg/liter) and avibactam (IC50, 2 mg/liter). Aztreonam showed high affinity for PBP3 (IC50, 0.06 to 0.12 mg/liter). Ceftazidime bound PBP3 at low concentrations (IC50, 0.06 to 0.25 mg/liter) and PBP1a/b at higher concentrations (4 mg/liter), whereas cefepime bound PBPs 1 to 4 at more even concentrations (IC50, 0.015 to 2 mg/liter). These PBP binding data on a comprehensive set of 13 clinically relevant β-lactams and β-lactamase inhibitors in K. pneumoniae enable, for the first time, the rational design and optimization of double β-lactam and β-lactam-β-lactamase inhibitor combinations.
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Affiliation(s)
- Dhruvitkumar S Sutaria
- Center for Pharmacometrics and Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, Florida, USA
| | - Bartolome Moya
- Center for Pharmacometrics and Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, Florida, USA
| | - Kari B Green
- Department of Chemistry, University of Florida, Gainesville, Florida, USA
| | - Tae Hwan Kim
- Center for Pharmacometrics and Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, Florida, USA
| | - Xun Tao
- Center for Pharmacometrics and Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, Florida, USA
| | - Yuanyuan Jiao
- Center for Pharmacometrics and Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, Florida, USA
| | - Arnold Louie
- Institute for Therapeutic Innovation, College of Medicine, University of Florida, Orlando, Florida, USA
| | - George L Drusano
- Institute for Therapeutic Innovation, College of Medicine, University of Florida, Orlando, Florida, USA
| | - Jürgen B Bulitta
- Center for Pharmacometrics and Systems Pharmacology, Department of Pharmaceutics, College of Pharmacy, University of Florida, Orlando, Florida, USA
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Liu C, Li C, Chen Y, Hao H, Liang J, Duan R, Guo Z, Zhang J, Zhao Z, Jing H, Wang X, Shao S. Role of Low-Molecular-Mass Penicillin-Binding Proteins, NagZ and AmpR in AmpC β-lactamase Regulation of Yersinia enterocolitica. Front Cell Infect Microbiol 2017; 7:425. [PMID: 29021974 PMCID: PMC5623720 DOI: 10.3389/fcimb.2017.00425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 09/14/2017] [Indexed: 11/23/2022] Open
Abstract
Yersinia enterocolitica encodes a chromosomal AmpC β-lactamase under the regulation of the classical ampR-ampC system. To obtain a further understanding to the role of low-molecular-mass penicillin-binding proteins (LMM PBPs) including PBP4, PBP5, PBP6, and PBP7, as well as NagZ and AmpR in ampC regulation of Y. enterocolitica, series of single/multiple mutant strains were systematically constructed and the ampC expression levels were determined by luxCDABE reporter system, reverse transcription-PCR (RT-PCR) and β-lactamase activity test. Sequential deletion of PBP5 and other LMM PBPs result in a continuously growing of ampC expression level, the β-lactamse activity of quadruple deletion strain YEΔ4Δ5Δ6Δ7 (pbp4, pbp5, pbp6, and pbp7 inactivated) is approached to the YEΔD123 (ampD1, ampD2, and ampD3 inactivated). Deletion of nagZ gene caused two completely different results in YEΔD123 and YEΔ4Δ5Δ6Δ7, NagZ is indispensable for YEΔ4Δ5Δ6Δ7 ampC derepression phenotype but dispensable for YEΔD123. AmpR is essential for ampC hyperproduction in these two types of strains, inactivation of AmpR notable reduced the ampC expression level in both YEΔD123 and YEΔ4Δ5Δ6Δ7.
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Affiliation(s)
- Chang Liu
- Department of Pathogenic Biology, School of Medical Science, Jiangsu University, Zhenjiang, China.,National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Chuchu Li
- Department of Pathogenic Biology, School of Medical Science, Jiangsu University, Zhenjiang, China.,National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Yuhuang Chen
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Huijing Hao
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Junrong Liang
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Ran Duan
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Zhaoke Guo
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Jing Zhang
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Zhongzhi Zhao
- Qinghai Institute for Endemic Diseases Prevention and Control, Xining, China
| | - Huaiqi Jing
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Xin Wang
- National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing, China
| | - Shihe Shao
- Department of Pathogenic Biology, School of Medical Science, Jiangsu University, Zhenjiang, China
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Suzuki T, Kimura K, Suzuki H, Banno H, Jin W, Wachino JI, Yamada K, Arakawa Y. Have group A streptococci with reduced penicillin susceptibility emerged? J Antimicrob Chemother 2014; 70:1258-9. [PMID: 25473026 DOI: 10.1093/jac/dku492] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Takeshi Suzuki
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
| | - Kouji Kimura
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
| | - Hiroshi Suzuki
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
| | - Hirotsugu Banno
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
| | - Wanchun Jin
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
| | - Jun-ichi Wachino
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
| | - Keiko Yamada
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
| | - Yoshichika Arakawa
- Department of Bacteriology, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan
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Chen CC, Yen MY, Wong WW, Li LH, Huang YL, Chen KW, Li SY. Tracing subsequent dissemination of a cluster of gonococcal infections caused by an ST1407-related clone harbouring mosaic penA alleles in Taiwan. J Antimicrob Chemother 2013; 68:1567-71. [PMID: 23508619 DOI: 10.1093/jac/dkt059] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Successful clones of Neisseria gonorrhoeae multiantigen sequence typing sequence type (ST) 1407 and ST1407-related genotypes have been reported to cause cefixime and ceftriaxone treatment failure in many countries. We characterized the 47 isolates of a strain cluster of ST4378, a genotype that differs in the porB sequence by only one nucleotide from ST1407, in Taiwan during April 2006 to June 2012. METHODS We identified 47 ST4378 isolates among our 2357 total isolates from the Gonococci-National Isolate Collection for Epidemiology. The corresponding patients' medical records were collected. The 47 isolates were further typed by multilocus sequence typing. Genes involved in β-lactam (ponA), quinolone (gyrA and parC) and multidrug (mtrR, porB1b and pilQ) resistance were sequenced. Antimicrobial susceptibility was determined by the disc diffusion test and Etest. RESULTS Cefixime MICs for the 47 isolates ranged from 0.016 to 0.19 mg/L and ceftriaxone MICs ranged from 0.012 to 0.094 mg/L. Forty-six of the 47 isolates had a mosaic penA allele type XXXIV and one had a new allele type XL, which appeared to be a recombinant of mosaic penA type XXXIV and non-mosaic penA type II. All of the isolates harboured nearly identical polymorphism in the ponA, gyrA, parC, mtrR, porB1b and pilQ genes. Among the 33 patients with known medical records, 25 (76%) were men who have sex with men (MSM), 3 (9%) were bisexual and 5 (15%) were heterosexual. Fourteen (42%) of the 33 patients had HIV, 8 (24%) had syphilis and 7 (21%) had both infections. CONCLUSIONS This is the first report of a cluster of ST1407-related strains in Taiwan. ST4378 is a genotype that may develop to cause third-generation cephalosporin treatment failures. Our results showed that ST4378 strains primarily transmitted in a high-risk MSM/bisexual network. The potential of these strains to become untreatable and spread to other low-risk sexual networks should be closely monitored.
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Affiliation(s)
- Chun-Chen Chen
- Research and Diagnostic Center, Centers for Disease Control, Taipei, Taiwan
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Kimura K, Wachino JI, Kurokawa H, Matsui M, Suzuki S, Yamane K, Nagano N, Shibayama K, Arakawa Y. High cephalosporin resistance due to amino acid substitutions in PBP1A and PBP2X in a clinical isolate of group B Streptococcus. J Antimicrob Chemother 2013; 68:1533-6. [PMID: 23449828 DOI: 10.1093/jac/dkt060] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Group B Streptococcus (GBS; Streptococcus agalactiae) has been regarded as uniformly susceptible to penicillins. However, we recently reported the existence of GBS with reduced penicillin susceptibility (PRGBS), with amino acid substitutions in penicillin-binding protein (PBP) 2X. Although most PRGBS show high MICs of ceftizoxime (4-64 mg/L) and cefotaxime (0.12-1 mg/L), those for strain B1 are exceptionally high (ceftizoxime MIC ≥256 mg/L and cefotaxime MIC 2 mg/L). We previously found an amino acid substitution (G539S) neighbouring the conserved K540TG motif in PBP1A in addition to the PRGBS-specific amino acid substitution Q557E in PBP2X of B1. The aim of this study was to reveal the effect of the amino acid substitutions in PBP1A and PBP2X of B1 on the high cephalosporin resistance. METHODS A ceftizoxime competition assay was performed to reveal the PBPs that are the main targets of ceftizoxime. We generated two allelic exchange mutants from β-lactam-susceptible GBS BAA-611. BAA-611 (B1PBP2X) contained the PBP2X gene derived from B1 and BAA-611 (B1PBP2X, B1PBP1A) contained both the PBP2X and the PBP1A gene derived from B1. These allelic exchange mutants and strain B1 were subjected to susceptibility testing. RESULTS The ceftizoxime competition assay revealed that PBP1A and PBP2X were the main targets of ceftizoxime. Although the MICs of ceftizoxime and cefotaxime for BAA-611 (B1PBP2X) were 64 and 0.5 mg/L, respectively, BAA-611 (B1PBP2X, B1PBP1A) showed high cephalosporin resistance (ceftizoxime MIC ≥256 mg/L and cefotaxime MIC 2 mg/L) comparable to B1. CONCLUSIONS The high cephalosporin resistance of GBS was caused by amino acid substitutions in PBP1A and PBP2X.
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Affiliation(s)
- Kouji Kimura
- Department of Bacteriology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan.
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