DOCSLIB.ORG

I Adding Insult to Injury

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
I Adding Insult to Injury Adding insult to injury: mechanistic basis for how AmpC mutations allow Pseudomonas aeruginosa to accelerate cephalosporin hydrolysis and evade avibactam by Cole Lee Slater A Thesis submitted to the Faculty of Graduate Studies of The University of Manitoba in partial fulfillment of the requirements for the degree of Master of Science Department of Microbiology University of Manitoba Winnipeg, Manitoba, Canada Copyright © 2020 Cole Lee Slater i Abstract Pseudomonas aeruginosa is a leading cause of nosocomial infections worldwide and notorious for its broad-spectrum resistance to antibiotics. A key mechanism that confers extensive resistance to β-lactam antibiotics is the inducible expression of AmpC, a highly efficient Ambler class C β-lactamase enzyme. Unfortunately, several P. aeruginosa clinical isolates expressing mutated forms of AmpC have been found to be clinically resistant to the novel antipseudomonal β-lactam/β-lactamase inhibitor (BLI) combinations ceftolozane/tazobactam and ceftazidime/avibactam. The objective of this thesis was to investigate the enzymatic activity of four of these reported AmpC mutants, E247K, G183D, T96I, and ∆G229–E247 (alongside wild-type (WT) AmpC from P. aeruginosa PAO1), to gain detailed insights into how these mutations circumvent these clinically vital antibiotic/inhibitor combinations. The effect of these mutations on the catalytic cycle of AmpC was found to be two- fold. First, they reduced the stability of the enzyme, which presumably increased its flexibility. This appeared to accelerate deacylation of the enzyme-bound β-lactam, which resulted in greater catalytic efficiencies towards ceftolozane and ceftazidime. Second, these mutations reduced the affinity of avibactam for AmpC by increasing the apparent activation energy barrier of the enzyme acylation step. The catalytic turnover of ceftolozane and ceftazidime was not influenced by this significantly, as deacylation was found to be the rate-limiting step for the breakdown of these antibiotics. It is remarkable that these mutations enhance the catalytic efficiency of AmpC towards ceftolozane and ceftazidime while simultaneously reducing susceptibility to inhibition by avibactam. It is our hope that the knowledge gained from the molecular analysis of these and other AmpC resistance mutants will aid the design of β-lactams and BLIs with reduced susceptibility to mutational resistance. ii Acknowledgements First and foremost, I would like to thank my supervisor, Dr. Brian Mark, for conceptualizing this intriguing research project and allowing me the opportunity to challenge it. His guidance and unwavering support throughout these past two years aided my academic success and development as a researcher. I would also like to thank the members of my advisory committee, Dr. Ayush Kumar and Dr. Frank Schweizer, for their frequent encouragement and valuable insight, as well as the Canadian Institute for Health Research (CIHR) for providing the financial support that made this research possible. I want to extend my sincerest gratitude towards Dr. Judith Winogrodzki for all the time and energy she spent towards formally training and educating me in molecular biology, enzyme kinetics, and protein crystallography. Her knowledge of and dedication to scientific research helped shape this project into what it is today. I am incredibly grateful for her guidance. I would also like to acknowledge Dr. Mazdak Khajehpour for offering his expertise and extensive knowledge in enzymology, as it helped me tremendously with both the analysis and interpretation of the overwhelming amounts of kinetic data collected for this project. I am also thankful for all the members of the Mark lab, who continue to provide a safe, friendly, and positive work environment. The same can be said for the rest of the students and faculty members within the Department of Microbiology, including the helpful support staff. Last, but certainly not least, I want to thank my family: mom, dad, Brennan, and Emily. Their unconditional love, support, and patience has helped me more than they will ever know. I wholeheartedly dedicate this thesis to them. iii Table of Contents Abstract ........................................................................................................................................ ii Acknowledgements ..................................................................................................................... iii Table of Contents ........................................................................................................................ iv List of Tables .............................................................................................................................. vii List of Figures ............................................................................................................................ viii List of Acronyms .......................................................................................................................... x 1. Introduction ............................................................................................................................. 1 1.1. Antibiotics: discovery and development of resistance ............................................... 1 1.2. Pseudomonas aeruginosa ........................................................................................... 2 1.3. β-lactam antibiotics ..................................................................................................... 2 1.3.1. Mechanism of action of β-lactam antibiotics ............................................... 2 1.3.2. Classification of β-lactam antibiotics .......................................................... 6 1.4. Resistance to β-lactam antibiotics ............................................................................. 10 1.5. β-lactamases .............................................................................................................. 11 1.5.1. Catalytic mechanism of β-lactamases ........................................................ 11 1.5.2. Classification of β-lactamases ................................................................... 14 1.6. AmpC β-lactamases .................................................................................................. 15 1.6.1. Overview .................................................................................................... 15 1.6.2. Regulation of AmpC expression ................................................................ 16 1.7. β-lactamase inhibitors ............................................................................................... 19 1.7.1. Mechanism of action of β-lactamase inhibitors ......................................... 19 iv 1.7.2. Classification of β-lactamase inhibitors ..................................................... 20 1.8. Research Premise ...................................................................................................... 25 1.9. Research Objectives .................................................................................................. 27 2. Materials and Methods .......................................................................................................... 28 2.1. Preparation of WT and mutant AmpC expression constructs ................................... 28 2.2. Expression and purification of WT and mutant AmpC enzymes ............................. 30 2.3. Kinetic characterization of WT and mutant AmpC enzymes ................................... 32 2.3.1. Michaelis–Menten kinetic analysis of WT and mutant AmpC enzymes ... 33 2.3.2. Avibactam inhibition assays ...................................................................... 34 2.3.3. Tazobactam inhibition assays .................................................................... 36 2.4. Melting temperature determination .......................................................................... 36 3. Results ..................................................................................................................................... 37 3.1. Expression and purification of WT and mutant AmpC enzymes ............................. 37 3.1.1. WT and mutant AmpC enzymes are stably expressed as soluble monomers ............................................................................................................. 37 3.2. Hydrolysis of ceftolozane and ceftazidime by WT and mutant AmpC enzymes ..... 40 3.2.1. WT AmpC displays a modest difference in its specificity towards ceftolozane and ceftazidime, with a slight preference for ceftazidime ................ 40 3.2.2. AmpC mutants exhibit increased catalytic efficiency towards ceftolozane and ceftazidime compared to WT AmpC ............................................................ 44 3.3. Hydrolysis of nitrocefin by WT and mutant AmpC enzymes .................................. 48 3.3.1. AmpC mutants exhibit decreased catalytic efficiency towards nitrocefin compared to WT AmpC ....................................................................................... 48 v 3.4. Inhibition of WT and mutant AmpC enzymes by avibactam and tazobactam ......... 51 3.4.1. AmpC mutants demonstrate reduced susceptibility to inhibition by avibactam ............................................................................................................. 51 3.4.2. Tazobactam inhibitory potency does not differ appreciably between the WT and mutant AmpC enzymes ...................................................................
Load more

Recommended publications
  • Process to Increase the Production of Clavam
    Europäisches Patentamt *EP000832247B1* (19) European Patent Office Office européen des brevets (11) EP 0 832 247 B1 (12) EUROPEAN PATENT SPECIFICATION (45) Date of publication and mention (51) Int Cl.7: C12N 15/54, C12P 17/18, of the grant of the patent: C12N 1/20 24.11.2004 Bulletin 2004/48 // (C12N1/20, C12R1:465) (21) Application number: 96921954.2 (86) International application number: PCT/EP1996/002497 (22) Date of filing: 06.06.1996 (87) International publication number: WO 1996/041886 (27.12.1996 Gazette 1996/56) (54) PROCESS TO INCREASE THE PRODUCTION OF CLAVAM ANTIBIOTICS VERFAHREN ZUR ERHÖHUNG DER PRODUKTION VON CLAVAM-ANTIBIOTIKA PROCEDE POUR AUGMENTER LA PRODUCTION D’ANTIBIOTIQUES CLAVAM (84) Designated Contracting States: (56) References cited: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC EP-A- 0 349 121 WO-A-94/18326 NL PT SE Designated Extension States: • FEMS MICROBIOLOGY LETTERS, vol. 110, 1993, SI pages 239-242, XP000601357 J.M.WARD AND J.E.HODGSON: "The biosynthetic genes for (30) Priority: 09.06.1995 GB 9511679 clavulanic acid and cephamycin production occur as a ’super-cluster’ in three (43) Date of publication of application: Streptomyces" cited in the application 01.04.1998 Bulletin 1998/14 • MICROBIOLOGY, vol. 140, no. 12, December 1994, pages 3367-3377, XP000601913 H.YU ET (73) Proprietors: AL.: "Possible involvement of the lat gene in the • SmithKline Beecham plc expression of the genes encoding ACV Brentford, Middlesex TW8 9GS (GB) synthetase (pcbAB) and isopenicillin N synthase • THE GOVERNORS OF THE UNIVERSITY OF (pcbC) in Streptomyces clavuligerus" cited in ALBERTA the application Edmonton, Alberta T6G 2E1 (CA) • MALMBERG ET AL: ’Precursor flux control through targeted chromosomal insertion of the (72) Inventors: lysine epsilon-aminotransferase (LAT) gene in • HOLMS, William, Henry Bioflux Limited Cephamycin C biosynthesis.’ JOURNAL OF 54 Dumbarton Road Glasgow G11 6AQ (GB) BACTERIOLOGY vol.
    [Show full text]
  • CLAVAMOX DROPS- Amoxicillin and Clavulanate Potassium Suspension Zoetis Inc
    CLAVAMOX DROPS- amoxicillin and clavulanate potassium suspension Zoetis Inc. ---------- CLAVAMOX® Drops CLAVAMOX® (amoxicillin and clavulanate potassium for oral suspension), USP Drops For veterinary oral suspension For use in dogs and cats CAUTION Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. DESCRIPTION Clavamox (amoxicillin trihydrate/clavulanate potassium), USP is an orally administered formulation comprised of the broad-spectrum antibiotic Amoxi® (amoxicillin trihydrate) and the β-lactamase inhibitor, clavulanate potassium (the potassium salt of clavulanic acid). Amoxicillin trihydrate is a semisynthetic antibiotic with a broad spectrum of bactericidal activity against many gram-positive and gram-negative, aerobic and anaerobic microorganisms. It does not resist destruction by β-lactamases; therefore, it is not effective against β-lactamase-producing bacteria. Chemically, it is D(-)-α-amino-p-hydroxybenzyl penicillin trihydrate. Clavulanic acid, an inhibitor of β-lactamase enzymes, is produced by the fermentation of Streptomyces clavuligerus. Clavulanic acid by itself has only weak antibacterial activity. Chemically, clavulanate potassium is potassium z-(3R,5R)-2-β-hydroxyethylidene clavam-3-carboxylate. CLINICAL PHARMACOLOGY Clavamox is stable in the presence of gastric acid and is not significantly influenced by gastric or intestinal contents. The 2 components are rapidly absorbed resulting in amoxicillin and clavulanic acid concentrations in serum, urine, and tissues similar to those produced when each is administered alone. Amoxicillin and clavulanic acid diffuse readily into most body tissues and fluids with the exception of brain and spinal fluid, which amoxicillin penetrates adequately when meninges are inflamed. Most of the amoxicillin is excreted unchanged in the urine.
    [Show full text]
  • Antibiotics/Antibacterial Drug Use, Their Marketing and Promotion During the Post-Antibiotic Golden Age and Their Role in Emergence of Bacterial Resistance
    Vol.6, No.5, 410-425 (2014) Health http://dx.doi.org/10.4236/health.2014.65059 Antibiotics/antibacterial drug use, their marketing and promotion during the post-antibiotic golden age and their role in emergence of bacterial resistance Godfrey S. Bbosa1,2, Norah Mwebaza1, John Odda1, David B. Kyegombe3, Muhammad Ntale1,4 1Department of Pharmacology and Therapeutics, Makerere University College of Health Sciences, Kampala, Uganda; Email: [email protected] 2Department of Primary Care and Population Sciences, University of London, London, UK 3Department of Chemistry, Makerere University, College of Natural Sciences, Kampala, Uganda 4Kampala International University School of Health Sciences, Ishaka Campus, Busyenyi, Uganda Received 20 December 2013; revised 7 January 2014; accepted 4 February 2014 Copyright © 2014 Godfrey S. Bbosa et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In accor- dance of the Creative Commons Attribution License all Copyrights © 2014 are reserved for SCIRP and the owner of the intellectual property Godfrey S. Bbosa et al. All Copyright © 2014 are guarded by law and by SCIRP as a guardian. ABSTRACT rial disease burden and hence a significant glo- bal public health problem. The resistant bacterial During the post-antibiotic golden age, it has diseases lead to the high cost, increased occur- seen a massive antibiotic/antibacterial produc- rence of adverse drug reactions, prolonged hos- tion and an increase in irrational use of these pitalization, the exposure to the second- and few existing drugs in the medical and veterinary third-line drugs like in MDR-TB and XDR-TB that practice, food industries, tissue cultures, agri- leads to toxicity and deaths as well as the in- culture and commercial ethanol production creased poor production in agriculture and ani- globally.
    [Show full text]
  • (12) Patent Application Publication (10) Pub. No.: US 2015/0150995 A1 Taft, III Et Al
    US 2015O150995A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2015/0150995 A1 Taft, III et al. (43) Pub. Date: Jun. 4, 2015 (54) CONJUGATED ANTI-MICROBIAL Publication Classification COMPOUNDS AND CONUGATED ANT-CANCER COMPOUNDS AND USES (51) Int. Cl. THEREOF A647/48 (2006.01) A63/546 (2006.01) (71) Applicant: PONO CORPORATION, Honolulu, HI A633/38 (2006.01) (US) (52) U.S. Cl. CPC ........... A61K47/480.15 (2013.01); A61K33/38 (72) Inventors: Karl Milton Taft, III, Honolulu, HI (2013.01); A61 K3I/546 (2013.01) (US); Jarred Roy Engelking, Honolulu, HI (US) (57) ABSTRACT (73) Assignee: PONO CORPORATION, Honolulu, HI Disclosed herein are synthesis methods for generation of (US) conjugated anti-microbial compounds and conjugated anti cancer compounds. Several embodiments, related to the uses (21) Appl.ppl. NNo.: 14/418,9079 of Such compoundsp in the treatment of infections, in particu lar those caused by drug-resistant bacteria. Some embodi (22) PCT Filed: Aug. 9, 2013 ments relate to targeting cancer based on the metabolic sig (86). PCT No.: PCT/US2O13/O54391 nature of tumor cells. S371 (c)(1), (2) Date: Jan. 30, 2015 NH Related U.S. Application Data O Ag" (60) Provisional application No. 61/742,443, filed on Aug. B-Lactam Silver Ion 9, 2012, provisional application No. 61/742,444, filed on Aug. 9, 2012. O O O O O O HSONaNO -pE (CHO)2SO2 OEt Br2 OEt 2W4 OH NOMe 1 2 3 Q Q H.N.S NH, NHT chicci -VV653C(CH) NaOH Bra-oe 2 2 S1N (C6H5)3C- SNN a NOMe MeO -co.
    [Show full text]
  • Clavamox Chewable
    CLAVAMOX® CHEWABLE The following adverse events reported for dogs and cats are listed in decreasing order of (amoxicillin and clavulanate potassium tablets) reporting frequency for CLAVAMOX: Anorexia, lethargy, vomiting and diarrhea. Chewable Tablets To report suspected adverse reactions, to obtain a Safety Data Sheet, or for technical assistance, call 1-888-963-8471. Antimicrobial For Oral Use In Dogs And Cats For additional information about adverse drug experience reporting for animal drugs, CAUTION: Federal (USA) law restricts this drug to use by or on the order of a licensed contact FDA at 1-888-FDA-VETS or http://www.fda.gov/AnimalVeterinary/SafetyHealth. veterinarian. ACTIONS: The 2 components are rapidly absorbed resulting in amoxicillin and clavulanic DESCRIPTION: CLAVAMOX CHEWABLE Tablet (amoxicillin and clavulanate potassium acid concentrations in serum, urine, and tissues similar to those produced when each is tablets) is an orally administered formulation comprised of the broad-spectrum antibiotic administered alone. Amoxi® (amoxicillin trihydrate) and the -lactamase inhibitor, clavulanate potassium β Amoxicillin and clavulanic acid diffuse readily into most body tissues and fluids with (the potassium salt of clavulanic acid). the exception of brain and spinal fluid, which amoxicillin penetrates adequately when Amoxicillin trihydrate is a semisynthetic antibiotic with a broad spectrum of bactericidal meninges are inflamed. Most of the amoxicillin is excreted unchanged in the urine. activity against many gram-positive and gram-negative, aerobic and anaerobic micro- Clavulanic acid’s penetration into spinal fluid is unknown at this time. Approximately 15% organisms. It does not resist destruction by β-lactamases; therefore, it is not effective of the administered dose of clavulanic acid is excreted in the urine within the first 6 hours.
    [Show full text]
  • Clavulanic Acid Production by Streptomyces Clavuligerus: Biogenesis, Regulation and Strain Improvement
    The Journal of Antibiotics (2013) 66, 411–420 & 2013 Japan Antibiotics Research Association All rights reserved 0021-8820/13 www.nature.com/ja REVIEW ARTICLE Clavulanic acid production by Streptomyces clavuligerus: biogenesis, regulation and strain improvement Ashish Paradkar Clavulanic acid (CA) is a potent b-lactamase inhibitor produced by Streptomyces clavuligerus and has been successfully used in combination with b-lactam antibiotics (for example, Augmentin) to treat infections caused by b-lactamase-producing pathogens. Since the discovery of CA in the late 1970s, significant information has accumulated on its biosynthesis, and regarding molecular mechanisms involved in the regulation of its production. Notably, the genes directing CA biosynthesis are clustered along with the genes responsible for the biosynthesis of the b-lactam antibiotic, cephamycin C, and co-regulated, which makes this organism unique in that the production of an antibiotic and production of a small molecule to protect the antibiotic from its enzymatic degradation are controlled by shared mechanisms. Traditionally, the industrial strain improvement programs have relied significantly on random mutagenesis and selection approach. However, the recent availability of the genome sequence of S. clavuligerus along with the capability to build metabolic models, and ability to engineer the organism by directed approaches, has created exciting opportunities to improve strain productivity more efficiently. This review will include focus mainly on the gene organization of the CA biosynthetic genes, regulatory mechanisms that affect its production, and will include perspectives on improving strain productivity. The Journal of Antibiotics (2013) 66, 411–420; doi:10.1038/ja.2013.26; published online 24 April 2013 Keywords: Actinomycetes; b-lactams; clavulanic acid; secondary metabolism; Streptomyces INTRODUCTION inhibitory property is due to the characteristic 3R, 5R stereochemistry Clavulanic acid (CA) is a potent inhibitor of a wide range of of the strained bicyclic nucleus structure (Figure 1).
    [Show full text]
  • CLAVAM 375/625/1000 Tablets
    For the Use of Registered Medicinal Practitioners or a Hospital or a Laboratory only (Amoxicillin and Potassium Clavulanate Tablets I.P.) CLAVAM 375/625/1000 Tablets 1. Name of the medicinal product Clavam 375 mg Tablets Clavam 625 mg Tablets Clavam 1000 mg Tablets 2. Qualitative and quantitative composition Clavam 375 Each film-coated tablet contains Amoxicillin Trihydrate I.P. equivalent to Amoxicillin…………………250 mg Potassium Clavulanate Diluted I.P. equivalent to Clavulanic Acid……………..125 mg Clavam 625 Each film-coated tablet contains Amoxicillin Trihydrate I.P. equivalent to Amoxicillin …………………500 mg Potassium Clavulanate Diluted I.P. equivalent to Clavulanic Acid ……………..125 mg Clavam 1000 Each film-coated tablet contains Amoxicillin Trihydrate I.P. equivalent to Amoxicillin …………………875 mg Potassium Clavulanate Diluted I.P. equivalent to Clavulanic Acid ……………..125 mg 3. Pharmaceutical form Film-coated tablet. 4. Clinical particulars 4.1 Therapeutic indications CLAVAM should be used in accordance with local official antibiotic-prescribing guidelines and local susceptibility data. CLAVAM is indicated for short term treatment of bacterial infections at the following sites when caused by amoxicillin-clavulanic acid-susceptible organisms: - Upper respiratory tract infections (including ENT) e.g. recurrent tonsillitis, sinusitis, otitis media - Lower respiratory tract infections e.g. acute exacerbations of chronic bronchitis, lobar and bronchopneumonia - Genito-urinary tract infections e.g. cystitis, urethritis, pyelonephritis - Skin and soft tissue infections e.g. boils, abscess, cellulitis, wound infections - Bone and joint infections e.g. osteomyelitis - Other Infections e.g. septic abortion, puerperal sepsis, intra-abdominal sepsis. 4.2 Posology and method of administration Dosage depends on the age, weight and renal function of the patient and the severity of the infection.
    [Show full text]
  • Clavulanic Acid Production by Streptomyces Clavuligerus: Insights from Systems Biology, Strain Engineering, and Downstream Processing
    antibiotics Review Clavulanic Acid Production by Streptomyces clavuligerus: Insights from Systems Biology, Strain Engineering, and Downstream Processing Víctor A. López-Agudelo 1 , David Gómez-Ríos 2 and Howard Ramirez-Malule 1,* 1 Escuela de Ingeniería Química, Universidad del Valle, A.A., Cali 25360, Colombia; [email protected] 2 Grupo de Investigación en Simulación, Diseño, Control y Optimización de Procesos (SIDCOP), Departamento de Ingeniería Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia; [email protected] * Correspondence: [email protected]; Tel.: +57-2-3212100 (ext. 7367) Abstract: Clavulanic acid (CA) is an irreversible β-lactamase enzyme inhibitor with a weak antibac- terial activity produced by Streptomyces clavuligerus (S. clavuligerus). CA is typically co-formulated with broad-spectrum β-lactam antibiotics such as amoxicillin, conferring them high potential to treat diseases caused by bacteria that possess β-lactam resistance. The clinical importance of CA and the complexity of the production process motivate improvements from an interdisciplinary standpoint by integrating metabolic engineering strategies and knowledge on metabolic and regulatory events through systems biology and multi-omics approaches. In the large-scale bioprocessing, optimization of culture conditions, bioreactor design, agitation regime, as well as advances in CA separation and purification are required to improve the cost structure associated to CA production. This review presents the recent insights in CA production by S. clavuligerus, emphasizing on systems biology approaches, strain engineering, and downstream processing. Citation: López-Agudelo, V.A.; Gómez-Ríos, D.; Ramirez-Malule, H. Keywords: clavulanic acid; Streptomyces clavuligerus; systems biology; strain engineering; Clavulanic Acid Production by downstream processing Streptomyces clavuligerus: Insights from Systems Biology, Strain Engineering, and Downstream Processing.
    [Show full text]
  • Mechanism of L,D-Transpeptidase Inhibition by Β-Lactams and Diazabicyclooctanes Zainab Edoo
    Mechanism of L,D-transpeptidase inhibition by β-lactams and diazabicyclooctanes Zainab Edoo To cite this version: Zainab Edoo. Mechanism of L,D-transpeptidase inhibition by β-lactams and diazabicyclooctanes. Microbiology and Parasitology. Sorbonne Université, 2019. English. NNT : 2019SORUS565. tel- 03173551 HAL Id: tel-03173551 https://tel.archives-ouvertes.fr/tel-03173551 Submitted on 18 Mar 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Sorbonne Université Ecole doctorale 515 « Complexité du Vivant » Laboratoire de Structures Bactériennes Impliquées dans la Modulation de la Résistance aux Antibiotiques Centre de Recherche des Cordeliers, UMRS 1138, Equipe 12 Mechanism of L,D-transpeptidase inhibition by β-lactams and diazabicyclooctanes. Mécanisme d’inhibition des L,D-transpeptidases par les β-lactamines et les diazabicyclooctanes. Par Zainab Edoo Thèse de doctorat de Biochimie Dirigée par Jean-Emmanuel Hugonnet Présentée et soutenue publiquement le 22 novembre 2019 Devant un jury composé de : Pr. Sandrine Betuing, Sorbonne Université Présidente
    [Show full text]
  • Antibiotic Resistance: Past, Present and Future
    Antibiotic Resistance: Past, Present and Future Karen Bush, PhD Professor of Practice in Biotechnology Indiana University Bloomington Great Plains Emerging Infectious Diseases Conference University of Iowa April 7, 2017 1 Conflicts of Interest (2016-2017) Retiree Compensation: 35 Years in Antibacterial R&D (1973–2009): Bristol-Myers Squibb, Johnson & Johnson, Pfizer (Wyeth) Consultant or Scientific Advisory Board: Achaogen, Allecra, Fedora, Gladius, Melinta, Merck, Roche, WarpDrive Research Support: Achaogen, Allergan/Actavis, Merck, Tetraphase Shareholder: Fedora, Johnson & Johnson 2 Outline of Presentation • Antibiotic resistance – Historical perspectives – Current situation – Future trends 3 FAQs Related to Antibiotic Resistance • What is an antibiotic/antimicrobial agent? – An antibiotic is generally defined as a drug that kills bacteria, or prevents them from growing – An antimicrobial agent is a drug that fight infections caused by bacteria, viruses or fungi/yeast • What is antimicrobial resistance? – The ability of a microbe (bacteria, virus, fungus) to evade the action of an antibiotic or antimicrobial agent – Resistance occurs when microbes have genetic mutations that allow them to grow in the presence of a previously effective drug https://www.cdc.gov/drugresistance/about.html ; http://www.clipartkid.com/tell-us-cliparts/ Antibiotic Resistance is a Fact of Life. 5 The CDC and WHO on Antibiotic Resistance • “Antibiotic resistance has been called one of the world's most pressing public health problems.” (http://www.cdc.gov/getsmart/antibiotic-
    [Show full text]
  • Lactamase Inhibitors by Streptomyces Species
    antibiotics Review Production of β-Lactamase Inhibitors by Streptomyces Species Daniela de Araújo Viana Marques 1,*, Suellen Emilliany Feitosa Machado 2, Valéria Carvalho Santos Ebinuma 3 ID , Carolina de Albuquerque Lima Duarte 4, Attilio Converti 5 and Ana Lúcia Figueiredo Porto 6 1 Campus Serra Talhada, University of Pernambuco, Avenida Custódio Conrado, 600, AABB, Serra Talhada, Pernambuco 56912-550, Brazil 2 Department of Antibiotics, Federal University of Pernambuco, Avenida da Engenharia, 2◦ andar, Cidade Universitária, Recife, Pernambuco 50740-600, Brazil; [email protected] 3 Department of Bioprocesses and Biotechnology, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Rodovia Araraquara-Jaú/Km 01, Araraquara 14800-903, Brazil; [email protected] 4 Campus Garanhuns, University of Pernambuco, Rua Capitão Pedro Rodrigues, 105, São José, Garanhuns, Pernambuco 55295-110, Brazil; [email protected] 5 Department of Civil, Chemical and Environmental Engineering, Chemical Pole, University of Genoa, Via Opera Pia 15, 16145 Genoa, Italy; [email protected] 6 Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco, Av. Dom Manoel de Medeiros, Recife, Pernambuco 52171-900, Brazil; [email protected] * Correspondence: [email protected]; Tel.: +55-81-995047420 Received: 30 May 2018; Accepted: 12 July 2018; Published: 17 July 2018 Abstract: β-Lactamase inhibitors have emerged as an effective alternative to reduce the effects of resistance against β-lactam antibiotics. The Streptomyces genus is known for being an exceptional natural source of antimicrobials and β-lactamase inhibitors such as clavulanic acid, which is largely applied in clinical practice. To protect against the increasing prevalence of multidrug-resistant bacterial strains, new antibiotics and β-lactamase inhibitors need to be discovered and developed.
    [Show full text]
  • B-Lactams and B-Lactamase Inhibitors: an Overview
    Downloaded from http://perspectivesinmedicine.cshlp.org/ on October 4, 2021 - Published by Cold Spring Harbor Laboratory Press b-Lactams and b-Lactamase Inhibitors: An Overview Karen Bush1 and Patricia A. Bradford2 1Molecular and Cellular Biochemistry, Indiana University, Bloomington, Indiana 47405 2AstraZeneca Pharmaceuticals, Waltham, Massachusetts 02451 Correspondence: [email protected] b-Lactams are the most widely used class of antibiotics. Since the discovery of benzylpeni- cillin in the 1920s, thousands of new penicillin derivatives and related b-lactam classes of cephalosporins, cephamycins, monobactams, and carbapenems have been discovered. Each new class of b-lactam has been developed either to increase the spectrum of activity to include additional bacterial species or to address specific resistance mechanisms that have arisen in the targeted bacterial population. Resistance to b-lactams is primarily because of bacterially produced b-lactamase enzymes that hydrolyze the b-lactam ring, thereby inactivating the drug. The newest effort to circumvent resistance is the development of novel broad-spectrum b-lactamase inhibitors that work against many problematic b-lac- tamases, including cephalosporinases and serine-based carbapenemases, which severely limit therapeutic options. This work provides a comprehensive overview of b-lactam anti- biotics that are currently in use, as well as a look ahead to several new compounds that are in the development pipeline. hen Alexander Fleming was searching for a consortium of scientists from England and the Wan antistaphylococcal bacteriophage in United States were able to optimize the isolation his laboratory in the 1920s, he deliberately left and identification of benzylpenicillin to assist in plates out on the bench to capture airborne the treatment of Allied soldiers in World War II agents that might also serve to kill staphylococci (Macfarlane 1979).
    [Show full text]