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Bano S, Hassan N, Rafiq M, Hassan F, Rehman M, Iqbal N, Ali H, Hasan F, Kang YQ. Biofilms as Battlefield Armor for Bacteria against Antibiotics: Challenges and Combating Strategies. Microorganisms 2023; 11:2595. [PMID: 37894253 PMCID: PMC10609369 DOI: 10.3390/microorganisms11102595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 08/25/2023] [Accepted: 09/04/2023] [Indexed: 10/29/2023] Open
Abstract
Bacterial biofilms are formed by communities, which are encased in a matrix of extracellular polymeric substances (EPS). Notably, bacteria in biofilms display a set of 'emergent properties' that vary considerably from free-living bacterial cells. Biofilms help bacteria to survive under multiple stressful conditions such as providing immunity against antibiotics. Apart from the provision of multi-layered defense for enabling poor antibiotic absorption and adaptive persistor cells, biofilms utilize their extracellular components, e.g., extracellular DNA (eDNA), chemical-like catalase, various genes and their regulators to combat antibiotics. The response of biofilms depends on the type of antibiotic that comes into contact with biofilms. For example, excessive production of eDNA exerts resistance against cell wall and DNA targeting antibiotics and the release of antagonist chemicals neutralizes cell membrane inhibitors, whereas the induction of protein and folic acid antibiotics inside cells is lowered by mutating genes and their regulators. Here, we review the current state of knowledge of biofilm-based resistance to various antibiotic classes in bacteria and genes responsible for biofilm development, and the key role of quorum sensing in developing biofilms and antibiotic resistance is also discussed. In this review, we also highlight new and modified techniques such as CRISPR/Cas, nanotechnology and bacteriophage therapy. These technologies might be useful to eliminate pathogens residing in biofilms by combating biofilm-induced antibiotic resistance and making this world free of antibiotic resistance.
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Affiliation(s)
- Sara Bano
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Noor Hassan
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering-College, Pakistan Institute of Engineering and Applied Sciences, Islamabad 44000, Pakistan
| | - Muhammad Rafiq
- Department of Microbiology, Balochistan University of Information Technology, Engineering and Management Sciences, Quetta 87300, Pakistan
| | - Farwa Hassan
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering-College, Pakistan Institute of Engineering and Applied Sciences, Islamabad 44000, Pakistan
| | - Maliha Rehman
- Department of Microbiology, Balochistan University of Information Technology, Engineering and Management Sciences, Quetta 87300, Pakistan
| | - Naveed Iqbal
- Department of Biotechnology & Informatics, Balochistan University of Information Technology, Engineering and Management Sciences, Quetta 87300, Pakistan
- The Department of Paediatrics and Child Health, Aga Khan University, Karachi 74800, Pakistan
| | - Hazrat Ali
- Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering-College, Pakistan Institute of Engineering and Applied Sciences, Islamabad 44000, Pakistan
| | - Fariha Hasan
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Ying-Qian Kang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education of Guizhou, Guiyang 550025, China
- Key Laboratory of Medical Microbiology and Parasitology, School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, China
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2
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Crowe-McAuliffe C, Wilson DN. Putting the antibiotics chloramphenicol and linezolid into context. Nat Struct Mol Biol 2022; 29:79-81. [DOI: 10.1038/s41594-022-00725-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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3
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Cools F, Delputte P, Cos P. The search for novel treatment strategies for Streptococcus pneumoniae infections. FEMS Microbiol Rev 2021; 45:6064299. [PMID: 33399826 PMCID: PMC8371276 DOI: 10.1093/femsre/fuaa072] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 01/01/2021] [Indexed: 12/13/2022] Open
Abstract
This review provides an overview of the most important novel treatment strategies against Streptococcus pneumoniae infections published over the past 10 years. The pneumococcus causes the majority of community-acquired bacterial pneumonia cases, and it is one of the prime pathogens in bacterial meningitis. Over the last 10 years, extensive research has been conducted to prevent severe pneumococcal infections, with a major focus on (i) boosting the host immune system and (ii) discovering novel antibacterials. Boosting the immune system can be done in two ways, either by actively modulating host immunity, mostly through administration of selective antibodies, or by interfering with pneumococcal virulence factors, thereby supporting the host immune system to effectively overcome an infection. While several of such experimental therapies are promising, few have evolved to clinical trials. The discovery of novel antibacterials is hampered by the high research and development costs versus the relatively low revenues for the pharmaceutical industry. Nevertheless, novel enzymatic assays and target-based drug design, allow the identification of targets and the development of novel molecules to effectively treat this life-threatening pathogen.
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Affiliation(s)
- F Cools
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - P Delputte
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - P Cos
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
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4
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Richter DC, Brenner T, Brinkmann A, Grabein B, Hochreiter M, Heininger A, Störzinger D, Briegel J, Pletz M, Weigand MA, Lichtenstern C. [New antibiotics for severe infections due to multidrug-resistant pathogens : Definitive treatment and escalation]. Anaesthesist 2020; 68:785-800. [PMID: 31555832 DOI: 10.1007/s00101-019-00646-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Multidrug-resistant pathogens often lead to treatment failure of antimicrobial regimens. After a period of imbalance between the occurrence/spread of resistance mechanisms and the development of new substances, some new substances have meanwhile been approved and many more are currently undergoing clinical testing. They are particularly effective against specific resistance mechanisms/pathogens and should be preserved for definitive treatment of an isolated pathogen. In the absence of alternatives reserve antibiotics, such as aztreonam and colistin have experienced a renaissance. They are again used in special infection scenarios and clinically tested in combination with new substances. Despite the introduction and development of new substances the building of resistance will at some time also render these (at least partially) ineffective. Therefore, their implementation must be carried out according to the antibiotic or infectious diseases stewardship.
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Affiliation(s)
- D C Richter
- Klinik für Anästhesiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland.
| | - T Brenner
- Klinik für Anästhesiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland
| | - A Brinkmann
- Klinik für Anästhesie, operative Intensivmedizin und spezielle Schmerztherapie, Klinikum Heidenheim, Heidenheim, Deutschland
| | - B Grabein
- Stabsstelle "Klinische Mikrobiologie und Krankenhaushygiene", Klinikum der Universität München, München, Deutschland
| | - M Hochreiter
- Klinik für Anästhesiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland
| | - A Heininger
- Zentrum für Infektiologie, Sektion für Krankenhaus- und Umwelthygiene, Universitätsklinikum Heidelberg, Heidelberg, Deutschland
| | - D Störzinger
- Apotheke, Universitätsklinikum Heidelberg, Heidelberg, Deutschland
| | - J Briegel
- Klinik für Anästhesiologie, Ludwig-Maximilians-Universität, München, Deutschland
| | - M Pletz
- Institut für Infektionsmedizin und Krankenhaushygiene, Universitätsklinikum Jena, Jena, Deutschland
| | - M A Weigand
- Klinik für Anästhesiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland
| | - C Lichtenstern
- Klinik für Anästhesiologie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland
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Abstract
Omadacycline is a novel aminomethylcycline antibiotic developed as a once-daily, intravenous and oral treatment for acute bacterial skin and skin structure infection (ABSSSI) and community-acquired bacterial pneumonia (CABP). Omadacycline, a derivative of minocycline, has a chemical structure similar to tigecycline with an alkylaminomethyl group replacing the glycylamido group at the C-9 position of the D-ring of the tetracycline core. Similar to other tetracyclines, omadacycline inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit. Omadacycline possesses broad-spectrum antibacterial activity against Gram-positive and Gram-negative aerobic, anaerobic, and atypical bacteria. Omadacycline remains active against bacterial isolates possessing common tetracycline resistance mechanisms such as efflux pumps (e.g., TetK) and ribosomal protection proteins (e.g., TetM) as well as in the presence of resistance mechanisms to other antibiotic classes. The pharmacokinetics of omadacycline are best described by a linear, three-compartment model following a zero-order intravenous infusion or first-order oral administration with transit compartments to account for delayed absorption. Omadacycline has a volume of distribution (Vd) ranging from 190 to 204 L, a terminal elimination half-life (t½) of 13.5-17.1 h, total clearance (CLT) of 8.8-10.6 L/h, and protein binding of 21.3% in healthy subjects. Oral bioavailability of omadacycline is estimated to be 34.5%. A single oral dose of 300 mg (bioequivalent to 100 mg IV) of omadacycline administered to fasted subjects achieved a maximum plasma concentration (Cmax) of 0.5-0.6 mg/L and an area under the plasma concentration-time curve from 0 to infinity (AUC0-∞) of 9.6-11.9 mg h/L. The free plasma area under concentration-time curve divided by the minimum inhibitory concentration (i.e., fAUC24h/MIC), has been established as the pharmacodynamic parameter predictive of omadacycline antibacterial efficacy. Several animal models including neutropenic murine lung infection, thigh infection, and intraperitoneal challenge model have documented the in vivo antibacterial efficacy of omadacycline. A phase II clinical trial on complicated skin and skin structure infection (cSSSI) and three phase III clinical trials on ABSSSI and CABP demonstrated the safety and efficacy of omadacycline. The phase III trials, OASIS-1 (ABSSSI), OASIS-2 (ABSSSI), and OPTIC (CABP), established non-inferiority of omadacycline to linezolid (OASIS-1, OASIS-2) and moxifloxacin (OPTIC), respectively. Omadacycline is currently approved by the FDA for use in treatment of ABSSSI and CABP. Phase II clinical trials involving patients with acute cystitis and acute pyelonephritis are in progress. Mild, transient gastrointestinal events are the predominant adverse effects associated with use of omadacycline. Based on clinical trial data to date, the adverse effect profile of omadacycline is similar to studied comparators, linezolid and moxifloxacin. Unlike tigecycline and eravacycline, omadacycline has an oral formulation that allows for step-down therapy from the intravenous formulation, potentially facilitating earlier hospital discharge, outpatient therapy, and cost savings. Omadacycline has a potential role as part of an antimicrobial stewardship program in the treatment of patients with infections caused by antibiotic-resistant and multidrug-resistant Gram-positive [including methicillin-resistant Staphylococcus aureus (MRSA)] and Gram-negative pathogens.
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7
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Crystal structure of ErmE - 23S rRNA methyltransferase in macrolide resistance. Sci Rep 2019; 9:14607. [PMID: 31601908 PMCID: PMC6787224 DOI: 10.1038/s41598-019-51174-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 09/25/2019] [Indexed: 12/14/2022] Open
Abstract
Pathogens often receive antibiotic resistance genes through horizontal gene transfer from bacteria that produce natural antibiotics. ErmE is a methyltransferase (MTase) from Saccharopolyspora erythraea that dimethylates A2058 in 23S rRNA using S-adenosyl methionine (SAM) as methyl donor, protecting the ribosomes from macrolide binding. To gain insights into the mechanism of macrolide resistance, the crystal structure of ErmE was determined to 1.75 Å resolution. ErmE consists of an N-terminal Rossmann-like α/ß catalytic domain and a C-terminal helical domain. Comparison with ErmC’ that despite only 24% sequence identity has the same function, reveals highly similar catalytic domains. Accordingly, superposition with the catalytic domain of ErmC’ in complex with SAM suggests that the cofactor binding site is conserved. The two structures mainly differ in the C-terminal domain, which in ErmE contains a longer loop harboring an additional 310 helix that interacts with the catalytic domain to stabilize the tertiary structure. Notably, ErmE also differs from ErmC’ by having long disordered extensions at its N- and C-termini. A C-terminal disordered region rich in arginine and glycine is also a present in two other MTases, PikR1 and PikR2, which share about 30% sequence identity with ErmE and methylate the same nucleotide in 23S rRNA.
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8
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Eljaaly K, Alharbi A, Alshehri S, Ortwine JK, Pogue JM. Plazomicin: A Novel Aminoglycoside for the Treatment of Resistant Gram-Negative Bacterial Infections. Drugs 2019; 79:243-269. [PMID: 30723876 DOI: 10.1007/s40265-019-1054-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Plazomicin is a novel semisynthetic parenteral aminoglycoside that inhibits bacterial protein synthesis. It was approved by the United States Food and Drug Administration for use in adults with complicated urinary tract infections (cUTI), including pyelonephritis. Plazomicin displays potent in vitro activity against Enterobacteriaceae, including both extended-spectrum β-lactamase-producing and carbapenem-resistant isolates. Plazomicin's enhanced Enterobacteriaceae activity is due to its stability to commonly encountered aminoglycoside-modifying enzymes that compromise the activity of traditional aminoglycosides. Plazomicin resistance in Enterobacteriaceae is via modification of the ribosomal binding site due to expression of 16S rRNA methyltransferases. Plazomicin does not display improved activity over traditional aminoglycosides against other problematic resistant Gram-negative bacteria, namely Pseudomonas aeruginosa and Acinetobacter baumannii. Plazomicin has been assessed in two phase III randomized controlled trials. The EPIC trial compared plazomicin and meropenem for the management of cUTI. In this trial, plazomicin demonstrated superiority in composite cure (81.7% vs 70.1%; difference 11.6%; 95% confidence interval [CI] 2.7-25.7) at the test-of-cure visit, which was driven by enhanced sustained microbiological eradication. The CARE trial compared plazomicin-based and colistin-based combinations in patients with serious infections due to carbapenem-resistant Enterobacteriaceae (CRE). In this analysis, plazomicin-based combinations were associated with numerically decreased mortality or serious disease-related complications when compared with colistin-based combinations (23.5% vs 50%, respectively; 90% CI -0.7 to 51.2). Furthermore, plazomicin was also associated with a lower incidence of nephrotoxicity than colistin. However, small sample sizes limit the interpretation of the findings in the CARE trial. Plazomicin is a novel aminoglycoside that offers clinicians an additional option for the management of CRE infections, with superior activity compared with traditional aminoglycosides and potentially improved efficacy and decreased toxicity compared with colistin.
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Affiliation(s)
- Khalid Eljaaly
- Department of Clinical Pharmacy, College of Pharmacy, King Abdulaziz University, P.O. Box 80200, Jeddah, 21589, Saudi Arabia.
- Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, AZ, USA.
| | - Aisha Alharbi
- Department of Clinical Pharmacy, College of Pharmacy, King Abdulaziz University, P.O. Box 80200, Jeddah, 21589, Saudi Arabia
| | - Samah Alshehri
- Department of Clinical Pharmacy, College of Pharmacy, King Abdulaziz University, P.O. Box 80200, Jeddah, 21589, Saudi Arabia
- Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, AZ, USA
| | - Jessica K Ortwine
- Department of Pharmacy Services, Parkland Health & Hospital System, Dallas, TX, USA
- University of Texas Southwestern Medical School, Dallas, TX, USA
| | - Jason M Pogue
- Department of Pharmacy Services, Sinai-Grace Hospital, Detroit Medical Center, Wayne State University of School of Medicine, Detroit, MI, USA
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9
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Schuster S, Vavra M, Kern WV. Efflux-Mediated Resistance to New Oxazolidinones and Pleuromutilin Derivatives in Escherichia coli with Class Specificities in the Resistance-Nodulation-Cell Division-Type Drug Transport Pathways. Antimicrob Agents Chemother 2019; 63:e01041-19. [PMID: 31209014 PMCID: PMC6709491 DOI: 10.1128/aac.01041-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 06/13/2019] [Indexed: 02/02/2023] Open
Abstract
A major contribution of the resistance-nodulation-cell division (RND)-transporter AcrB to resistance to oxazolidinones and pleuromutilin derivatives in Escherichia coli was confirmed. However, we discovered significant differences in efflux inhibitor activities, specificities of the homologous pump YhiV (MdtF), and the impact of AcrB pathway mutations. Particularly, entrance channel double-mutation I38F I671T and distal binding pocket mutation F615A revealed class-specific transport routes of oxazolidinones and pleuromutilin derivatives. The findings could contribute to the understanding of the RND-type multidrug transport pathways.
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Affiliation(s)
- Sabine Schuster
- Division of Infectious Diseases, Department of Medicine II, University Hospital and Medical Center, Freiburg, Germany
| | - Martina Vavra
- Division of Infectious Diseases, Department of Medicine II, University Hospital and Medical Center, Freiburg, Germany
| | - Winfried V Kern
- Division of Infectious Diseases, Department of Medicine II, University Hospital and Medical Center, Freiburg, Germany
- Faculty of Medicine, Albert-Ludwigs-University, Freiburg, Germany
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10
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Zhang P, Ma S. Recent development of leucyl-tRNA synthetase inhibitors as antimicrobial agents. MEDCHEMCOMM 2019; 10:1329-1341. [PMID: 31534653 PMCID: PMC6727470 DOI: 10.1039/c9md00139e] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 05/26/2019] [Indexed: 12/14/2022]
Abstract
Aminoacyl-tRNA synthetases (aaRSs) widely exist in organisms and mediate protein synthesis. Inhibiting these synthetases can lead to the termination of protein synthesis and subsequently achieve antibacterial and antiparasitic purposes. Moreover, the structures of aaRSs found in eukaryotes have considerable structural differences compared to those in prokaryotes, based on which it is possible to develop highly selective inhibitors. Leucyl-tRNA synthetase (LeuRS) with unique synthesis and editing sites is one of 20 kinds of aaRSs. Many inhibitors targeting LeuRS have been designed and synthesized, some of which have entered clinical use. For example, the benzoxaborole compound AN2690 has been approved by the FDA for the treatment of onychomycosis. AN3365 is suspended in the phase II clinical trial due to the rapid development of AN3365 resistance, but it may be used in combination with other antibiotics. The aaRSs, especially LeuRS, are being considered as targets of new potential anti-infective drugs for the treatment of not only bacterial or fungal infections but also infections by trypanosomes and malaria parasites. This review mainly describes the development of LeuRS inhibitors, focusing on their mechanisms of action, structure-activity relationships (SARs), and in vitro and in vivo activities.
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Affiliation(s)
- Panpan Zhang
- Department of Medicinal Chemistry , Key Laboratory of Chemical Biology , Ministry of Education , School of Pharmaceutical Sciences , Shandong University , 44, West Culture Road , Jinan 250012 , P. R. China . E mail:
| | - Shutao Ma
- Department of Medicinal Chemistry , Key Laboratory of Chemical Biology , Ministry of Education , School of Pharmaceutical Sciences , Shandong University , 44, West Culture Road , Jinan 250012 , P. R. China . E mail:
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11
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Viswanathan V, Pendsey S, Radhakrishnan C, Rege TD, Ahdal J, Jain R. Methicillin-Resistant Staphylococcus aureus in Diabetic Foot Infection in India: A Growing Menace. INT J LOW EXTR WOUND 2019; 18:236-246. [DOI: 10.1177/1534734619853668] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Diabetic foot infection (DFI) is a serious and common complication of diabetes mellitus. These infections are potentially disastrous and rapidly progress to deeper spaces and tissues. If not treated promptly and appropriately, DFI can be incurable or even lead to septic gangrene, which may require foot amputation. Mostly, these infections are polymicrobial, where Gram-positive pathogens mainly Staphylococcus aureus play a dominant causative role. Methicillin-resistant Staphylococcus aureus (MRSA) is present in 10% to 32% of diabetic infections and is associated with a higher rate of treatment failure, morbidity, and hospitalization cost in patients with DFIs. The increasing resistance of bacteria and the adverse effects pertaining to the safety and tolerability towards currently available anti-MRSA agents have limited the available treatment options for patients with DFI. Infection control, antimicrobial stewardship, and rapid diagnostics based on the microbiological culture and the antimicrobial susceptibility testing results are important components in helping curb this disturbing trend. Emphasis to revisit a vigorous research effort in order to improve the therapeutic options for the increasingly resistant and highly adaptable MRSA is the need of hour. Through this review article, we have made an attempt to explore the ongoing therapeutic trends in the management of DFI and highlighted the challenges in treatment of DFI. We have also given a brief overview of a few novel drugs that are under development to treat MRSA infections.
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Affiliation(s)
| | | | | | | | | | - Rishi Jain
- Wockhardt Ltd, Bandra Kurla Complex, Mumbai, India
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12
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Louzoun Zada S, Green KD, Shrestha SK, Herzog IM, Garneau-Tsodikova S, Fridman M. Derivatives of Ribosome-Inhibiting Antibiotic Chloramphenicol Inhibit the Biosynthesis of Bacterial Cell Wall. ACS Infect Dis 2018; 4:1121-1129. [PMID: 29714997 DOI: 10.1021/acsinfecdis.8b00078] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Here, we describe the preparation and evaluation of α,β-unsaturated carbonyl derivatives of the bacterial translation inhibiting antibiotic chloramphenicol (CAM). Compared to the parent antibiotic, two compounds containing α,β-unsaturated ketones (1 and 4) displayed a broader spectrum of activity against a panel of Gram-positive pathogens with a minimum inhibitory concentration range of 2-32 μg/mL. Interestingly, unlike the parent CAM, these compounds do not inhibit bacterial translation. Microscopic evidence and metabolic labeling of a cell wall peptidoglycan suggested that compounds 1 and 4 caused extensive damage to the envelope of Staphylococcus aureus cells by inhibition of the early stage of cell wall peptidoglycan biosynthesis. Unlike the effect of membrane-disrupting antimicrobial cationic amphiphiles, these compounds did not rapidly permeabilize the bacterial membrane. Like the parent antibiotic CAM, compounds 1 and 4 had a bacteriostatic effect on S. aureus. Both compounds 1 and 4 were cytotoxic to immortalized nucleated mammalian cells; however, neither caused measurable membrane damage to mammalian red blood cells. These data suggest that the reported CAM-derived antimicrobial agents offer a new molecular scaffold for development of novel bacterial cell wall biosynthesis inhibiting antibiotics.
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Affiliation(s)
- Sivan Louzoun Zada
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Keith D. Green
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Sanjib K. Shrestha
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Ido M. Herzog
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Sylvie Garneau-Tsodikova
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40536-0596, United States
| | - Micha Fridman
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, 6997801, Israel
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13
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Donald BJ, Surani S, Deol HS, Mbadugha UJ, Udeani G. Spotlight on solithromycin in the treatment of community-acquired bacterial pneumonia: design, development, and potential place in therapy. Drug Des Devel Ther 2017; 11:3559-3566. [PMID: 29263651 PMCID: PMC5732564 DOI: 10.2147/dddt.s119545] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Community-acquired bacterial pneumonia (CABP) is a leading cause of death worldwide. However, antibacterial agents used to treat common pathogens in CABP are marked by adverse drug events and increasing antimicrobial resistance. Solithromycin is a new ketolide antibiotic, based on the macrolide antibiotic structure, being studied for use in CABP. It has efficacy in vitro against the common causative pathogens in CABP including Streptococcus pneumoniae, Haemophilus influenzae, and atypical pathogens. In Phase II and Phase III clinical trials, it has been demonstrated efficacious as a single agent for treatment of CABP with an apparently milder adverse event profile than alternative agents.
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Affiliation(s)
- Bryan J Donald
- Department of Pharmacy, Corpus Christi Medical Center, Corpus Christi, TX.,Department of Clinical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA
| | - Salim Surani
- Department of Pulmonology/Critical Care, Corpus Christi Medical Center, Corpus Christi, TX.,Department of Medicine, College of Medicine, Texas A&M University Health Science Center, College Station, TX.,Department of Medicine, College of Osteopathic Medicine, University of North Texas Health Science Center, Denton, TX
| | - Harmeet S Deol
- Department of Pharmacy, Corpus Christi Medical Center, Corpus Christi, TX.,Department of Pharmacy Services, Yale New Haven Hospital, New Haven, CT
| | - Uche J Mbadugha
- Department of Pharmacy, Corpus Christi Medical Center, Corpus Christi, TX
| | - George Udeani
- Department of Pharmacy, Corpus Christi Medical Center, Corpus Christi, TX.,Pharmacy Practice, College of Pharmacy, Texas A&M University Health Science Center, Kingsville, TX, USA
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14
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Allred TK, Manoni F, Harran PG. Exploring the Boundaries of “Practical”: De Novo Syntheses of Complex Natural Product-Based Drug Candidates. Chem Rev 2017; 117:11994-12051. [DOI: 10.1021/acs.chemrev.7b00126] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tyler K. Allred
- Department of Chemistry and
Biochemistry, University of California−Los Angeles, 607 Charles
E. Young Drive East, Los Angeles, California 90095-1569, United States
| | - Francesco Manoni
- Department of Chemistry and
Biochemistry, University of California−Los Angeles, 607 Charles
E. Young Drive East, Los Angeles, California 90095-1569, United States
| | - Patrick G. Harran
- Department of Chemistry and
Biochemistry, University of California−Los Angeles, 607 Charles
E. Young Drive East, Los Angeles, California 90095-1569, United States
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15
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Zhanel GG, Hartel E, Adam H, Zelenitsky S, Zhanel MA, Golden A, Schweizer F, Gorityala B, Lagacé-Wiens PRS, Walkty AJ, Gin AS, Hoban DJ, Lynch JP, Karlowsky JA. Solithromycin: A Novel Fluoroketolide for the Treatment of Community-Acquired Bacterial Pneumonia. Drugs 2017; 76:1737-1757. [PMID: 27909995 DOI: 10.1007/s40265-016-0667-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Solithromycin is a novel fluoroketolide developed in both oral and intravenous formulations to address increasing macrolide resistance in pathogens causing community-acquired bacterial pneumonia (CABP). When compared with its macrolide and ketolide predecessors, solithromycin has several structural modifications which increase its ribosomal binding and reduce its propensity to known macrolide resistance mechanisms. Solithromycin, like telithromycin, affects 50S ribosomal subunit formation and function, as well as causing frame-shift errors during translation. However, unlike telithromycin, which binds to two sites on the ribosome, solithromycin has three distinct ribosomal binding sites. Its desosamine sugar interacts at the A2058/A2059 cleft in domain V (as all macrolides do), an extended alkyl-aryl side chain interacts with base pair A752-U2609 in domain II (similar to telithromycin), and a fluorine at C-2 of solithromycin provides additional binding to the ribosome. Studies describing solithromycin activity against Streptococcus pneumoniae have reported that it does not induce erm-mediated resistance because it lacks a cladinose moiety, and that it is less susceptible than other macrolides to mef-mediated efflux due to its increased ribosomal binding and greater intrinsic activity. Solithromycin has demonstrated potent in vitro activity against the most common CABP pathogens, including macrolide-, penicillin-, and fluoroquinolone-resistant isolates of S. pneumoniae, as well as Haemophilus influenzae and atypical bacterial pathogens. Solithromycin displays multi-compartment pharmacokinetics, a large volume of distribution (>500 L), approximately 67% bioavailability when given orally, and serum protein binding of 81%. Its major metabolic pathway appears to follow cytochrome P450 (CYP) 3A4, with metabolites of solithromycin undergoing biliary excretion. Its serum half-life is approximately 6-9 h, which is sufficient for once-daily administration. Pharmacodynamic activity is best described as fAUC0-24/MIC (the ratio of the area under the free drug concentration-time curve from 0 to 24 h to the minimum inhibitory concentration of the isolate). Solithromycin has completed one phase II and two phase III clinical trials in patients with CABP. In the phase II trial, oral solithromycin was compared with oral levofloxacin and demonstrated similar clinical success rates in the intention-to-treat (ITT) population (84.6 vs 86.6%). Clinical success in the clinically evaluable patients group was 83.6% of patients receiving solithromycin compared with 93.1% for patients receiving levofloxacin. In SOLITAIRE-ORAL, a phase III trial which assessed patients receiving oral solithromycin or oral moxifloxacin for CABP, an equivalent (non-inferior) early clinical response in the ITT population was demonstrated for patients receiving either solithromycin (78.2%) or moxifloxacin (77.9%). In a separate phase III trial, SOLITAIRE-IV, patients receiving intravenous-to-oral solithromycin (79.3%) demonstrated non-inferiority as the primary outcome of early clinical response in the ITT population compared with patients receiving intravenous-to-oral moxifloxacin (79.7%). Overall, solithromycin has been well tolerated in clinical trials, with gastrointestinal adverse events being most common, occurring in approximately 10% of patients. Transaminase elevation occurred in 5-10% of patients and generally resolved following cessation of therapy. None of the rare serious adverse events that occurred with telithromycin (i.e., hepatotoxicity) have been noted with solithromycin, possibly due to the fact that solithromycin (unlike telithromycin) does not possess a pyridine moiety in its chemical structure, which has been implicated in inhibiting nicotinic acetylcholine receptors. Because solithromycin is a possible substrate and inhibitor of both CYP3A4 and P-glycoprotein (P-gp), it may display drug interactions similar to macrolides such as clarithromycin. Overall, the in vitro activity, clinical efficacy, tolerability, and safety profile of solithromycin demonstrated to date suggest that it continues to be a promising treatment for CABP.
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Affiliation(s)
- George G Zhanel
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada. .,Department of Medicine, Health Sciences Centre, Winnipeg, MB, Canada. .,Department of Clinical Microbiology, Health Sciences Centre, MS673-820 Sherbrook Street, Winnipeg, MB, R3A 1R9, Canada.
| | - Erika Hartel
- College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada
| | - Heather Adam
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.,Department of Clinical Microbiology, Health Sciences Centre, MS673-820 Sherbrook Street, Winnipeg, MB, R3A 1R9, Canada
| | | | - Michael A Zhanel
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada
| | - Alyssa Golden
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada
| | - Frank Schweizer
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.,Department of Chemistry, Faculty of Science, University of Manitoba, Winnipeg, MB, Canada
| | - Bala Gorityala
- Department of Chemistry, Faculty of Science, University of Manitoba, Winnipeg, MB, Canada
| | - Philippe R S Lagacé-Wiens
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.,Department of Clinical Microbiology, Saint Boniface Hospital, Winnipeg, MB, Canada
| | - Andrew J Walkty
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.,Department of Medicine, Health Sciences Centre, Winnipeg, MB, Canada.,Department of Clinical Microbiology, Health Sciences Centre, MS673-820 Sherbrook Street, Winnipeg, MB, R3A 1R9, Canada
| | - Alfred S Gin
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.,College of Pharmacy, University of Manitoba, Winnipeg, MB, Canada.,Department of Pharmacy, Health Sciences Centre, Winnipeg, MB, Canada
| | - Daryl J Hoban
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.,Department of Clinical Microbiology, Health Sciences Centre, MS673-820 Sherbrook Street, Winnipeg, MB, R3A 1R9, Canada
| | - Joseph P Lynch
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Medicine, The David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - James A Karlowsky
- Department of Medical Microbiology, Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.,Department of Clinical Microbiology, Saint Boniface Hospital, Winnipeg, MB, Canada
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16
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Bougas A, Vlachogiannis IA, Gatos D, Arenz S, Dinos GP. Dual effect of chloramphenicol peptides on ribosome inhibition. Amino Acids 2017; 49:995-1004. [PMID: 28283906 DOI: 10.1007/s00726-017-2406-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 02/28/2017] [Indexed: 11/29/2022]
Abstract
Chloramphenicol peptides were recently established as useful tools for probing nascent polypeptide chain interaction with the ribosome, either biochemically, or structurally. Here, we present a new 10mer chloramphenicol peptide, which exerts a dual inhibition effect on the ribosome function affecting two distinct areas of the ribosome, namely the peptidyl transferase center and the polypeptide exit tunnel. According to our data, the chloramphenicol peptide bound on the chloramphenicol binding site inhibits the formation of both acetyl-phenylalanine-puromycin and acetyl-lysine-puromycin, showing, however, a decreased peptidyl transferase inhibition compared to chloramphenicol-mediated inhibition per se. Additionally, we found that the same compound is a strong inhibitor of green fluorescent protein synthesis in a coupled in vitro transcription-translation assay as well as a potent inhibitor of lysine polymerization in a poly(A)-programmed ribosome, showing that an additional inhibitory effect may exist. Since chemical protection data supported the interaction of the antibiotic with bases A2058 and A2059 near the entrance of the tunnel, we concluded that the extra inhibition effect on the synthesis of longer peptides is coming from interactions of the peptide moiety of the drug with residues comprising the ribosomal tunnel, and by filling up the tunnel and blocking nascent chain progression through the restricted tunnel. Therefore, the dual interaction of the chloramphenicol peptide with the ribosome increases its inhibitory effect and opens a new window for improving the antimicrobial potency of classical antibiotics or designing new ones.
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Affiliation(s)
- Anthony Bougas
- Department of Biochemistry, School of Medicine, University of Patras, 26500, Patras, Greece
| | | | - Dimitrios Gatos
- Department of Chemistry, University of Patras, Patras, Greece
| | - Stefan Arenz
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University of Munich, Feodor- Lynen-Strasse 25, 81377, Munich, Germany
| | - George P Dinos
- Department of Biochemistry, School of Medicine, University of Patras, 26500, Patras, Greece.
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17
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Bush K, Page MGP. What we may expect from novel antibacterial agents in the pipeline with respect to resistance and pharmacodynamic principles. J Pharmacokinet Pharmacodyn 2017; 44:113-132. [DOI: 10.1007/s10928-017-9506-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 01/20/2017] [Indexed: 12/25/2022]
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18
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Dunbar AB, Taylor JR. Inhibition of protein synthesis but not β-adrenergic receptors blocks reconsolidation of a cocaine-associated cue memory. ACTA ACUST UNITED AC 2016; 23:391-8. [PMID: 27421890 PMCID: PMC4947232 DOI: 10.1101/lm.042838.116] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 05/18/2016] [Indexed: 11/25/2022]
Abstract
Previously consolidated memories have the potential to enter a state of lability upon memory recall, during which time the memory can be altered before undergoing an additional consolidation-like process and being stored again as a long-term memory. Blocking reconsolidation of aberrant memories has been proposed as a potential treatment for psychiatric disorders including addiction. Here we investigated of the effect of systemically administering the protein synthesis inhibitor cycloheximide or the β-adrenergic antagonist propranolol on reconsolidation. Rats were trained to self-administer cocaine, during which each lever press resulted in the presentation of a cue paired with an intravenous infusion of cocaine. After undergoing lever press extinction to reduce operant responding, the cue memory was reactivated and rats were administered systemic injections of propranolol, cycloheximide, or vehicle. Post-reactivation cycloheximide, but not propranolol, resulted in a reactivation-dependent decrease in cue-induced reinstatement, indicative of reconsolidation blockade by protein synthesis inhibition. The present data indicate that systemically targeting protein synthesis as opposed to the β-adrenergic system may more effectively attenuate the reconsolidation of a drug-related memory and decrease drug-seeking behavior.
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Affiliation(s)
- Amber B Dunbar
- Department of Psychiatry, Division of Molecular Psychiatry, New Haven, Connecticut 06520, USA Department of Psychology, Yale University, New Haven, Connecticut 06520, USA
| | - Jane R Taylor
- Department of Psychiatry, Division of Molecular Psychiatry, New Haven, Connecticut 06520, USA Department of Psychology, Yale University, New Haven, Connecticut 06520, USA Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut 06520, USA
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19
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Cheng G, Dai M, Ahmed S, Hao H, Wang X, Yuan Z. Antimicrobial Drugs in Fighting against Antimicrobial Resistance. Front Microbiol 2016; 7:470. [PMID: 27092125 PMCID: PMC4824775 DOI: 10.3389/fmicb.2016.00470] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/21/2016] [Indexed: 01/18/2023] Open
Abstract
The outbreak of antimicrobial resistance, together with the lack of newly developed antimicrobial drugs, represents an alarming signal for both human and animal healthcare worldwide. Selection of rational dosage regimens for traditional antimicrobial drugs based on pharmacokinetic/pharmacodynamic principles as well as development of novel antimicrobials targeting new bacterial targets or resistance mechanisms are key approaches in tackling AMR. In addition to the cellular level resistance (i.e., mutation and horizontal gene transfer of resistance determinants), the community level resistance (i.e., bilofilms and persisters) is also an issue causing antimicrobial therapy difficulties. Therefore, anti-resistance and antibiofilm strategies have currently become research hotspot to combat antimicrobial resistance. Although metallic nanoparticles can both kill bacteria and inhibit biofilm formation, the toxicity is still a big challenge for their clinical applications. In conclusion, rational use of the existing antimicrobials and combinational use of new strategies fighting against antimicrobial resistance are powerful warranties to preserve potent antimicrobial drugs for both humans and animals.
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Affiliation(s)
- Guyue Cheng
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Menghong Dai
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Saeed Ahmed
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and Ministry of Agriculture Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural University Wuhan, China
| | - Haihong Hao
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Xu Wang
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University Wuhan, China
| | - Zonghui Yuan
- Ministry of Agriculture Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural UniversityWuhan, China; National Reference Laboratory of Veterinary Drug Residues (HZAU) and Ministry of Agriculture Key Laboratory for the Detection of Veterinary Drug Residues in Foods, Huazhong Agricultural UniversityWuhan, China
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20
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Khan SN, Khan AU. Breaking the Spell: Combating Multidrug Resistant 'Superbugs'. Front Microbiol 2016; 7:174. [PMID: 26925046 PMCID: PMC4757689 DOI: 10.3389/fmicb.2016.00174] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 02/01/2016] [Indexed: 12/15/2022] Open
Abstract
Multidrug-resistant (MDR) bacteria have become a severe threat to community wellbeing. Conventional antibiotics are getting progressively more ineffective as a consequence of resistance, making it imperative to realize improved antimicrobial options. In this review we emphasized the microorganisms primarily reported of being resistance, referred as ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacteriaceae) accentuating their capacity to "escape" from routine antimicrobial regimes. The upcoming antimicrobial agents showing great potential and can serve as alternative therapeutic options are discussed. We also provided succinct overview of two evolving technologies; specifically network pharmacology and functional genomics profiling. Furthermore, In vivo imaging techniques can provide novel targets and a real time tool for potential lead molecule assessment. The employment of such approaches at prelude of a drug development process, will enables more informed decisions on candidate drug selection and will maximize or predict therapeutic potential before clinical testing.
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Affiliation(s)
| | - Asad U. Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim UniversityAligarh, India
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21
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Lin SY, Huang CH, Ko WC, Chen YH, Hsueh PR. Recent developments in antibiotic agents for the treatment of complicated intra-abdominal infections. Expert Opin Pharmacother 2015; 17:339-54. [DOI: 10.1517/14656566.2016.1122756] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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22
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Resistance to ketolide antibiotics by coordinated expression of rRNA methyltransferases in a bacterial producer of natural ketolides. Proc Natl Acad Sci U S A 2015; 112:12956-61. [PMID: 26438831 DOI: 10.1073/pnas.1512090112] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ketolides are promising new antimicrobials effective against a broad range of Gram-positive pathogens, in part because of the low propensity of these drugs to trigger the expression of resistance genes. A natural ketolide pikromycin and a related compound methymycin are produced by Streptomyces venezuelae strain ATCC 15439. The producer avoids the inhibitory effects of its own antibiotics by expressing two paralogous rRNA methylase genes pikR1 and pikR2 with seemingly redundant functions. We show here that the PikR1 and PikR2 enzymes mono- and dimethylate, respectively, the N6 amino group in 23S rRNA nucleotide A2058. PikR1 monomethylase is constitutively expressed; it confers low resistance at low fitness cost and is required for ketolide-induced activation of pikR2 to attain high-level resistance. The regulatory mechanism controlling pikR2 expression has been evolutionary optimized for preferential activation by ketolide antibiotics. The resistance genes and the induction mechanism remain fully functional when transferred to heterologous bacterial hosts. The anticipated wide use of ketolide antibiotics could promote horizontal transfer of these highly efficient resistance genes to pathogens. Taken together, these findings emphasized the need for surveillance of pikR1/pikR2-based bacterial resistance and the preemptive development of drugs that can remain effective against the ketolide-specific resistance mechanism.
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23
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Cellular pharmacokinetics and intracellular activity of the novel peptide deformylase inhibitor GSK1322322 against Staphylococcus aureus laboratory and clinical strains with various resistance phenotypes: studies with human THP-1 monocytes and J774 murine macrophages. Antimicrob Agents Chemother 2015; 59:5747-60. [PMID: 26169402 DOI: 10.1128/aac.00827-15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 07/04/2015] [Indexed: 01/01/2023] Open
Abstract
GSK1322322 is a peptide deformylase inhibitor active against Staphylococcus aureus strains resistant to currently marketed antibiotics. Our aim was to assess the activity of GSK1322322 against intracellular S. aureus using an in vitro pharmacodynamic model and, in parallel, to examine its cellular pharmacokinetics and intracellular disposition. For intracellular activity analysis, we used an established model of human THP-1 monocytes and tested one fully susceptible S. aureus strain (ATCC 25923) and 8 clinical strains with resistance to oxacillin, vancomycin, daptomycin, macrolides, clindamycin, linezolid, or moxifloxacin. Uptake, accumulation, release, and subcellular distribution (cell fractionation) of [(14)C]GSK1322322 were examined in uninfected murine J774 macrophages and uninfected and infected THP-1 monocytes. GSK1322322 demonstrated a uniform activity against the intracellular forms of all S. aureus strains tested, disregarding their resistance phenotypes, with a maximal relative efficacy (E max) of a 0.5 to 1 log10 CFU decrease compared to the original inoculum within 24 h and a static concentration (C s) close to its MIC in broth. Influx and efflux were very fast (<5 min to equilibrium), and accumulation was about 4-fold, with no or a minimal effect of the broad-spectrum eukaryotic efflux transporter inhibitors gemfibrozil and verapamil. GSK1322322 was recovered in the cell-soluble fraction and was dissociated from the main subcellular organelles and from bacteria (in infected cells). The results of this study show that GSK1322322, as a typical novel deformylase inhibitor, may act against intracellular forms of S. aureus. They also suggest that GSK1322322 has the ability to freely diffuse into and out of eukaryotic cells as well as within subcellular compartments.
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24
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Fernandes P. The global challenge of new classes of antibacterial agents: an industry perspective. Curr Opin Pharmacol 2015; 24:7-11. [PMID: 26119487 DOI: 10.1016/j.coph.2015.06.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 06/10/2015] [Indexed: 01/21/2023]
Abstract
With rising antibiotic resistance and the fear of returning to the pre-penicillin era, incentives are being provided for developing novel antibiotics. The hurdles faced by antibiotic developers include the difficulty in discovering novel chemicals that have selectivity and the increased regulatory scrutiny for safety and efficacy. Furthermore, the demonstration of superiority is essential in order to rationalize pricing and to assure a return on investment. Suggestions are provided to overcome each of these hurdles in order to prevent the antibiotic pipeline from running dry.
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Affiliation(s)
- Prabhavathi Fernandes
- Cempra, Inc., Building Two, 6320 Quadrangle Drive, Suite 360, Chapel Hill, NC 27517, USA.
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25
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Naderer O, Jones LS, Zhu J, Coffin MD, Kurtinecz M, Dumont E. The Effect of Food and Formulation on the Pharmacokinetics, Safety, and Tolerability of GSK1322322 in Healthy Volunteers. Clin Pharmacol Drug Dev 2015; 4:49-55. [PMID: 26097792 PMCID: PMC4467258 DOI: 10.1002/cpdd.165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 08/25/2014] [Indexed: 11/25/2022]
Abstract
GSK1322322 is the first in a new class of antibiotics that inhibit peptide deformylase, necessary for bacterial protein maturation. Previously, low absolute bioavailability was observed for the 1500-mg oral tablet formulation, resulting in a less than dose-proportional increase from the 1000-mg dose. Furthermore, high variability of pharmacokinetic (PK) parameters within cohorts was suggested to be associated with differences in body weight. This open-label, randomized, 4-period, crossover, single-dose phase I study in healthy individuals compared the PK, safety, and tolerability of free base oral tablets under fasted or fed conditions with intravenous and oral mesylate salt solution of GSK1322322 under fasted conditions. Absolute bioavailability of GSK1322322 1500-mg free base tablets under fasted conditions, fed conditions, and oral mesylate salt solution was 57%, 77%, and 92%, respectively. Moderate-fat/calorie food intake increased area under the concentration–time curve (AUC0−∞) by 36%, maintained maximum observed concentration (Cmax), and delayed time to Cmax. It appeared that AUC0−∞ decreased with body weight, whereas clearance increased. GSK1322322 administration resulted in only mild-to-moderate adverse events. These results support future clinical investigations of the free base oral tablet formulation of GSK1322322 1500 mg after intake of a moderate-fat/calorie meal, including further investigation of a potential weight-based dosage change.
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Affiliation(s)
| | | | - John Zhu
- GlaxoSmithKline Upper Merion, PA, USA
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26
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Polikanov YS, Starosta AL, Juette MF, Altman RB, Terry DS, Lu W, Burnett BJ, Dinos G, Reynolds KA, Blanchard SC, Steitz TA, Wilson DN. Distinct tRNA Accommodation Intermediates Observed on the Ribosome with the Antibiotics Hygromycin A and A201A. Mol Cell 2015; 58:832-44. [PMID: 26028538 DOI: 10.1016/j.molcel.2015.04.014] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 02/23/2015] [Accepted: 04/07/2015] [Indexed: 01/12/2023]
Abstract
The increase in multi-drug-resistant bacteria is limiting the effectiveness of currently approved antibiotics, leading to a renewed interest in antibiotics with distinct chemical scaffolds. We have solved the structures of the Thermus thermophilus 70S ribosome with A-, P-, and E-site tRNAs bound and in complex with either the aminocyclitol-containing antibiotic hygromycin A (HygA) or the nucleoside antibiotic A201A. Both antibiotics bind at the peptidyl transferase center and sterically occlude the CCA-end of the A-tRNA from entering the A site of the peptidyl transferase center. Single-molecule Förster resonance energy transfer (smFRET) experiments reveal that HygA and A201A specifically interfere with full accommodation of the A-tRNA, leading to the presence of tRNA accommodation intermediates and thereby inhibiting peptide bond formation. Thus, our results provide not only insight into the mechanism of action of HygA and A201A, but also into the fundamental process of tRNA accommodation during protein synthesis.
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Affiliation(s)
- Yury S Polikanov
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Agata L Starosta
- Gene Center and Department for Biochemistry, University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany
| | - Manuel F Juette
- Department of Physiology and Biophysics, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Roger B Altman
- Department of Physiology and Biophysics, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Daniel S Terry
- Department of Physiology and Biophysics, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Wanli Lu
- Department of Chemistry, Portland State University, Portland, OR 97207, USA
| | - Benjamin J Burnett
- Department of Physiology and Biophysics, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - George Dinos
- Department of Biochemistry, School of Medicine, University of Patras, 26500 Patras, Greece
| | - Kevin A Reynolds
- Department of Chemistry, Portland State University, Portland, OR 97207, USA
| | - Scott C Blanchard
- Department of Physiology and Biophysics, Weill Medical College of Cornell University, New York, NY 10065, USA; Tri-Institutional Training Program in Chemical Biology, New York, NY 10065, USA.
| | - Thomas A Steitz
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
| | - Daniel N Wilson
- Gene Center and Department for Biochemistry, University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany; Center for integrated Protein Science Munich (CiPSM), University of Munich, Feodor-Lynenstr. 25, 81377 Munich, Germany.
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27
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Krokidis M, Bougas A, Stavropoulou M, Kalpaxis D, Dinos GP. The slow dissociation rate of K-1602 contributes to the enhanced inhibitory activity of this novel alkyl-aryl-bearing fluoroketolide. J Enzyme Inhib Med Chem 2015; 31:276-82. [PMID: 25807301 DOI: 10.3109/14756366.2015.1018246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ketolides belong to the latest generation of macrolides and are not only effective against macrolide susceptible bacterial strains but also against some macrolide resistant strains. Here we present data providing insights into the mechanism of action of K-1602, a novel alkyl-aryl-bearing fluoroketolide. According to our data, the K-1602 interacts with the ribosome as a one-step slow binding inhibitor, displaying an association rate constant equal to 0.28 × 10(4) M(-1) s(-1) and a dissociation rate constant equal to 0.0025 min(-1). Both constants contribute to produce an overall inhibition constant Ki equal to 1.49 × 10(-8) M, which correlates very well with the superior activity of this compound when compared with many other ketolides or fluoroketolides.
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Affiliation(s)
- Marios Krokidis
- a Department of Pharmacology , Medical School, University of Athens , Athens , Greece
| | - Anthony Bougas
- b Laboratory of Biochemistry , School of Medicine, University of Patras , Patras , Greece , and
| | - Maria Stavropoulou
- c Department of Chemistry , Technical University of Munich , Munich , Germany
| | - Dimitrios Kalpaxis
- b Laboratory of Biochemistry , School of Medicine, University of Patras , Patras , Greece , and
| | - George P Dinos
- b Laboratory of Biochemistry , School of Medicine, University of Patras , Patras , Greece , and
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28
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Sahuquillo-Arce JM, Hernández-Cabezas A, Yarad-Auad F, Ibáñez-Martínez E, Falomir-Salcedo P, Ruiz-Gaitán A. Carbapenemases: A worldwide threat to antimicrobial therapy. World J Pharmacol 2015; 4:75-95. [DOI: 10.5497/wjp.v4.i1.75] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 11/07/2014] [Accepted: 12/01/2014] [Indexed: 02/07/2023] Open
Abstract
Carbapenems are potent β-lactams with activity against extended-spectrum cephalosporinases and β-lactamases. These antibiotics, derived from thienamycn, a carbapenem produced by the environmental bacterium Streptomyces cattleya, were initially used as last-resort treatments for severe Gram-negative bacterial infections presenting resistance to most β-lactams but have become an empirical option in countries with high prevalence of Extended Spectrum β-lactamase-producing bacterial infections. Imipenem, the first commercially available carbapenem, was approved for clinical use in 1985. Since then, a wide variety of carbapenem-resistant bacteria has appeared, primarily Enterobacteriaceae such as Escherichia coli or Klebsiella pneumoniae (K. pneumoniae), Pseudomonas aeruginosa and Acinetobacter baumannii, presenting different resistance mechanisms. The most relevant mechanism is the production of carbapenem-hydrolyzing β-lactamases, also known as carbapenemases. These enzymes also inactivate all known β-lactams, and some of these enzymes can be acquired through horizontal gene transfer. Moreover, plasmids, transposons and integrons harboring these genes typically carry other resistance determinants, rendering the recipient bacteria resistant to almost all currently used antimicrobials, as is the case for K. pneumoniae carbapenemase - or New Delhi metallo-β-lactamases-type enzymes. The recent advent of these enzymes in the health landscape presents a serious challenge. First, the emergence of carbapenemases limits the currently available treatment options; second, these enzymes pose a risk to patients, as some studies have demonstrated high mortality associated with carbapenemase-producing bacterial infections; and third, these circumstances require an extra cost to sanitary systems, which are particularly cumbersome in developing countries. Therefore, emphasis should be placed on the early detection of these enzymes, the prevention of the spread of carbapenemase-producing bacteria and the development of new drugs resistant to carbapenemase hydrolysis.
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Microbiome changes in healthy volunteers treated with GSK1322322, a novel antibiotic targeting bacterial peptide deformylase. Antimicrob Agents Chemother 2014; 59:1182-92. [PMID: 25487798 DOI: 10.1128/aac.04506-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
GSK1322322 is a novel antibacterial agent under development, and it has known antibacterial activities against multidrug-resistant respiratory and skin pathogens through its inhibition of the bacterial peptide deformylase. Here, we used next-generation sequencing (NGS) of the bacterial 16S rRNA genes from stool samples collected from 61 healthy volunteers at the predosing and end-of-study time points to determine the effects of GSK1322322 on the gastrointestinal (GI) microbiota in a phase I, randomized, double-blind, and placebo-controlled study. GSK1322322 was administered either intravenously (i.v.) only or in an oral-i.v. combination in single- and repeat-dose-escalation infusions. Analysis of the 16S rRNA sequence data found no significant changes in the relative abundances of GI operational taxonomic units (OTUs) between the prestudy and end-of-study samples for either the placebo- or i.v.-only-treated subjects. However, oral-i.v. treatment resulted in significant decreases in some bacterial taxa, the Firmicutes and Bacteroidales, and increases in others, the Betaproteobacteria, Gammaproteobacteria, and Bifidobacteriaceae. Microbiome diversity plots clearly differentiated the end-of-study oral-i.v.-dosed samples from all others collected. The changes in genome function as inferred from species composition suggest an increase in bacterial transporter and xenobiotic metabolism pathways in these samples. A phylogenetic analysis of the peptide deformylase protein sequences collected from the published genomes of clinical isolates previously tested for GSK1322322 in vitro susceptibility and GI bacterial reference genomes suggests that antibiotic target homology is one of several factors that influences the response of GI microbiota to this antibiotic. Our study shows that dosing regimen and target class are important factors when considering the impact of antibiotic usage on GI microbiota. (This clinical trial was registered at the GlaxoSmithKline Clinical Study Register under study identifier PDF 113376.).
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Discovery and characterization of a novel class of pyrazolopyrimidinedione tRNA synthesis inhibitors. J Antibiot (Tokyo) 2014; 68:361-7. [DOI: 10.1038/ja.2014.163] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 10/27/2014] [Accepted: 11/02/2014] [Indexed: 01/12/2023]
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Multidrug-resistant Gram-negative bacteria in solid organ transplant recipients with bacteremias. Eur J Clin Microbiol Infect Dis 2014; 34:431-7. [PMID: 25388855 DOI: 10.1007/s10096-014-2271-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 10/28/2014] [Indexed: 12/11/2022]
Abstract
Bloodstream infections (BSIs) remain as life-threatening complications and are associated with significant morbidity and mortality among solid organ transplant (SOT) recipients. Multidrug-resistant (MDR) Gram-negative bacteria can cause serious bacteremias in these recipients. Reviews have aimed to investigate MDR Gram-negative bacteremias; however, they were lacking in SOT recipients in the past. To better understand the characteristics of bacteremias due to MDR Gram-negative bacteria, optimize preventive and therapeutic strategies, and improve the outcomes of SOT recipients, this review summarize the epidemiology, clinical and laboratory characteristics, and explores the mechanisms, prevention, and treatment of MDR Gram-negative bacteria.
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Page MGP, Bush K. Discovery and development of new antibacterial agents targeting Gram-negative bacteria in the era of pandrug resistance: is the future promising? Curr Opin Pharmacol 2014; 18:91-7. [DOI: 10.1016/j.coph.2014.09.008] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 09/11/2014] [Indexed: 11/30/2022]
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Bassetti M, Righi E. Eravacycline for the treatment of intra-abdominal infections. Expert Opin Investig Drugs 2014; 23:1575-84. [DOI: 10.1517/13543784.2014.965253] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Delgado-Valverde M, Sojo-Dorado J, Pascual A, Rodríguez-Baño J. Clinical management of infections caused by multidrug-resistant Enterobacteriaceae. Ther Adv Infect Dis 2014; 1:49-69. [PMID: 25165544 DOI: 10.1177/2049936113476284] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Enterobacteriaceae showing resistance to cephalosporins due to extended-spectrum β-lactamases (ESBLs) or plasmid-mediated AmpC enzymes, and those producing carbapenemases have spread worldwide during the last decades. Many of these isolates are also resistant to other first-line agents such as fluoroquinolones or aminoglycosides, leaving few available options for therapy. Thus, older drugs such as colistin and fosfomycin are being increasingly used. Infections caused by these bacteria are associated with increased morbidity and mortality compared with those caused by their susceptible counterparts. Most of the evidence supporting the present recommendations is from in vitro data, animal studies, and observational studies. While carbapenems are considered the drugs of choice for ESBL and AmpC producers, recent data suggest that certain alternatives may be suitable for some types of infections. Combined therapy seems superior to monotherapy in the treatment of invasive infections caused by carbapenemase-producing Enterobacteriaceae. Optimization of dosage according to pharmacokinetics/pharmacodynamics data is important for the treatment of infections caused by isolates with borderline minimum inhibitory concentration due to low-level resistance mechanisms. The increasing frequency and the rapid spread of multidrug resistance among the Enterobacteriaceae is a true and complex public health problem.
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Affiliation(s)
- Mercedes Delgado-Valverde
- Infectious Diseases and Clinical Microbiology Unit, Hospital Universitario Virgen Macarena, Seville, Spain
| | - Jesús Sojo-Dorado
- Infectious Diseases and Clinical Microbiology Unit, Hospital Universitario Virgen Macarena, Seville, Spain
| | - Alvaro Pascual
- Infectious Diseases and Clinical Microbiology Unit, Hospital Universitario Virgen Macarena, and Department of Microbiology, University of Seville, Seville, Spain
| | - Jesús Rodríguez-Baño
- Infectious Diseases and Clinical Microbiology Unit, Hospital Universitario Virgen Macarena, Avda Dr Fedriani 3, 41009 Seville, Spain
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Fair RJ, Tor Y. Antibiotics and bacterial resistance in the 21st century. PERSPECTIVES IN MEDICINAL CHEMISTRY 2014; 6:25-64. [PMID: 25232278 PMCID: PMC4159373 DOI: 10.4137/pmc.s14459] [Citation(s) in RCA: 841] [Impact Index Per Article: 84.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 06/24/2014] [Accepted: 06/24/2014] [Indexed: 12/11/2022]
Abstract
Dangerous, antibiotic resistant bacteria have been observed with increasing frequency over the past several decades. In this review the factors that have been linked to this phenomenon are addressed. Profiles of bacterial species that are deemed to be particularly concerning at the present time are illustrated. Factors including economic impact, intrinsic and acquired drug resistance, morbidity and mortality rates, and means of infection are taken into account. Synchronously with the waxing of bacterial resistance there has been waning antibiotic development. The approaches that scientists are employing in the pursuit of new antibacterial agents are briefly described. The standings of established antibiotic classes as well as potentially emerging classes are assessed with an emphasis on molecules that have been clinically approved or are in advanced stages of development. Historical perspectives, mechanisms of action and resistance, spectrum of activity, and preeminent members of each class are discussed.
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Affiliation(s)
- Richard J Fair
- Department for Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, Berlin, Germany
| | - Yitzhak Tor
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
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Karaiskos I, Giamarellou H. Multidrug-resistant and extensively drug-resistant Gram-negative pathogens: current and emerging therapeutic approaches. Expert Opin Pharmacother 2014; 15:1351-70. [PMID: 24766095 PMCID: PMC4819585 DOI: 10.1517/14656566.2014.914172] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
INTRODUCTION In the era of multidrug-resistant, extensively drug-resistant (XDR) and even pandrug-resistant Gram-negative microorganisms, the medical community is facing the threat of untreatable infections particularly those caused by carbapenemase-producing bacteria, that is, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii. Therefore, all the presently available antibiotics, as well as for the near future compounds, are presented and discussed. AREAS COVERED Current knowledge concerning mechanisms of action, in vitro activity and interactions, pharmacokinetic/pharmacodynamics, clinical efficacy and toxicity issues for revived and novel antimicrobial agents overcoming current resistance mechanisms, including colistin, tigecycline, fosfomycin, temocillin, carbapenems, and antibiotics still under development for the near future such as plazomicin, eravacycline and carbapenemase inhibitors is discussed. EXPERT OPINION Colistin is active in vitro and effective in vivo against XDR carbapenemase-producing microorganisms in the critically ill host, whereas tigecycline, with the exception of P. aeruginosa, has a similar spectrum of activity. The efficacy of combination therapy in bacteremias and ventilator-associated pneumonia caused by K. pneumoniae carbapenemase producers seems to be obligatory, whereas in cases of P. aeruginosa and A. baumannii its efficacy is questionable. Fosfomycin, which is active against P. aeruginosa and K. pneumoniae, although promising, shares poor experience in XDR infections. The in vivo validity of the newer potent compounds still necessitates the evaluation of Phase III clinical trials particularly in XDR infections.
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Affiliation(s)
- Ilias Karaiskos
- Hygeia General Hospital, 6th Department of Internal Medicine, Erythrou Stavrou Str & Kifisias Avenue, Marousi, Athens, 15123, Greece
| | - Helen Giamarellou
- Hygeia General Hospital, 6th Department of Internal Medicine, 4, Erythrou Stavrou Str & Kifisias Avenue, Marousi, Athens, 15123, Greece+302 106 867 946; +302 106 867 377;
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Arya H, Coumar MS. Virtual screening of traditional Chinese medicine (TCM) database: identification of fragment-like lead molecules for filariasis target asparaginyl-tRNA synthetase. J Mol Model 2014; 20:2266. [PMID: 24842326 DOI: 10.1007/s00894-014-2266-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 04/23/2014] [Indexed: 12/28/2022]
Abstract
Lymphatic filariasis (LF) is a vector borne infectious disease caused by the nematode Wuchereria bancrofti, Brugia malayi, and Brugia timori. Over 120 million people are affected by LF in the world, of which two-thirds are in Asia. The infection restricts the normal flow of lymph from the infected area resulting in swelling of the extremities and causing permanent disability. As the available drugs for the treatment of LF are becoming ineffective due to the development of resistance, there is an urgent need to find new leads for drug development. In this study, asparaginyl-tRNA synthetase (AsnRS; PDB ID: 2XGT) essential for the protein bio-synthesis in the filarial nematode was used to carry out virtual screening (VS) of plant constituents from traditional Chinese medicine (TCM) database. Docking as well as E-pharmacophore based VS were carried out to identify the hits. The top scoring hits, Agri 1 (1,3,8-trihydroxy-4,5-dimethoxyxanthen-9-one-3-O-beta-D-glucopyranoside) and Agri 2 (5,7-dihydroxy-2-propylchromone 7-O-beta-D-glucopyranoside), constituents of Agrimonia pilosa, were selected for molecular dynamics (MD) simulation study for 10 ns. MD simulation showed that both the glycosides Agri 1 and Agri 2 were forming stable interactions with the target protein. Moreover, docking and MD simulation of the lead A (1,3,8-trihydroxy-4,5-dimethoxyxanthen-9-one; Mol. Wt.: 304.25; CLogP: 3.07) and lead B (5,7-dihydroxy-2-propylchromone; Mol. Wt.: 220.22; CLogP: 3.02), the aglycones of Agri 1 and Agri 2, respectively, were carried out with the target AsnRS. The in silico investigations of the aglycones suggest that the lead B could be a suitable fragment-like lead molecule for anti-filarial drug discovery.
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Affiliation(s)
- Hemant Arya
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Kalapet, Puducherry, 605014, India
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Abstract
The ribosome is one of the main antibiotic targets in the bacterial cell. Crystal structures of naturally produced antibiotics and their semi-synthetic derivatives bound to ribosomal particles have provided unparalleled insight into their mechanisms of action, and they are also facilitating the design of more effective antibiotics for targeting multidrug-resistant bacteria. In this Review, I discuss the recent structural insights into the mechanism of action of ribosome-targeting antibiotics and the molecular mechanisms of bacterial resistance, in addition to the approaches that are being pursued for the production of improved drugs that inhibit bacterial protein synthesis.
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Rodvold KA, McConeghy KW. Methicillin-Resistant Staphylococcus aureus Therapy: Past, Present, and Future. Clin Infect Dis 2013; 58 Suppl 1:S20-7. [DOI: 10.1093/cid/cit614] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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40
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de Souza Mendes CD, de Souza Antunes AM. Pipeline of Known Chemical Classes of Antibiotics. Antibiotics (Basel) 2013; 2:500-34. [PMID: 27029317 PMCID: PMC4790266 DOI: 10.3390/antibiotics2040500] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 11/28/2013] [Accepted: 11/29/2013] [Indexed: 01/18/2023] Open
Abstract
Many approaches are used to discover new antibiotic compounds, one of the most widespread being the chemical modification of known antibiotics. This type of discovery has been so important in the development of new antibiotics that most antibiotics used today belong to the same chemical classes as antibiotics discovered in the 1950s and 1960s. Even though the discovery of new classes of antibiotics is urgently needed, the chemical modification of antibiotics in known classes is still widely used to discover new antibiotics, resulting in a great number of compounds in the discovery and clinical pipeline that belong to existing classes. In this scenario, the present article presents an overview of the R&D pipeline of new antibiotics in known classes of antibiotics, from discovery to clinical trial, in order to map out the technological trends in this type of antibiotic R&D, aiming to identify the chemical classes attracting most interest, their spectrum of activity, and the new subclasses under development. The result of the study shows that the new antibiotics in the pipeline belong to the following chemical classes: quinolones, aminoglycosides, macrolides, oxazolidinones, tetracyclines, pleuromutilins, beta-lactams, lipoglycopeptides, polymyxins and cyclic lipopeptides.
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Affiliation(s)
- Cristina d'Urso de Souza Mendes
- Graduate Program in Technology of Chemical and Biochemical Processes, Technology Center, Federal University of Rio de Janeiro (UFRJ), EQ/UFRJ, Centro de Tecnologia, Bloco E, Ilha do Fundão, Rio de Janeiro-RJ 21949-900, Brazil.
- Brazilian National Institute of Industrial Property, INPI/Rua Mayrink Veiga No. 9/19 andar, CEP 20090-910, Rio de Janeiro-RJ 20090-910, Brazil.
| | - Adelaide Maria de Souza Antunes
- Graduate Program in Technology of Chemical and Biochemical Processes, Technology Center, Federal University of Rio de Janeiro (UFRJ), EQ/UFRJ, Centro de Tecnologia, Bloco E, Ilha do Fundão, Rio de Janeiro-RJ 21949-900, Brazil.
- Brazilian National Institute of Industrial Property, INPI/Rua Mayrink Veiga No. 9/19 andar, CEP 20090-910, Rio de Janeiro-RJ 20090-910, Brazil.
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Patel G, Rana MM, Huprikar S. Multidrug-resistant bacteria in organ transplantation: an emerging threat with limited therapeutic options. Curr Infect Dis Rep 2013; 15:504-13. [PMID: 24101302 DOI: 10.1007/s11908-013-0371-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Multidrug-resistant organisms (MDROs) are an emerging threat in solid organ transplantation (SOT). The changing epidemiology of these MDROs is reviewed along with the growing evidence regarding risk factors and outcomes associated with both colonization and infection in SOT. The management of these infections is complicated by the lack of antimicrobial agents available to treat these infections, and only a handful of new agents, especially for the treatment of MDR GNR infections, are being evaluated in clinical trials. Due to the increased prevalence of MDROs and limited treatment options, as well as organ shortages, transplant candidacy and use of organs from donors with evidence of MDRO colonization and/or infection remain controversial. Increasing collaboration between transplant programs, individual practitioners, infection control programs, and researchers in antimicrobial development will be needed to face this challenge.
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Affiliation(s)
- Gopi Patel
- Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1090, New York, NY, 10029, USA,
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Penetration of GSK1322322 into epithelial lining fluid and alveolar macrophages as determined by bronchoalveolar lavage. Antimicrob Agents Chemother 2013; 58:419-23. [PMID: 24189245 DOI: 10.1128/aac.01836-13] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
GSK1322322 is a potent peptide deformylase inhibitor with in vitro and in vivo activity against multidrug-resistant skin and respiratory pathogens. This report provides plasma and intrapulmonary pharmacokinetics, safety, and tolerability of GSK1322322 after repeat (twice daily intravenous dosing for 4 days) dosing at 1,500 mg. Plasma samples were collected over the last 12-hour dosing interval of repeat dosing following the day 4 morning dose (the last dose). Bronchoalveolar lavage samples were collected once in each subject, either before or at 2 or 6 h after the last intravenous dose. Plasma area under the concentration-time curve (AUC0-τ) was 66.7 μg · h/ml, and maximum concentration of drug in serum (Cmax) was 25.4 μg/ml following repeat doses of intravenous GSK1322322. The time course of epithelial lining fluid (ELF) and alveolar macrophages (AM) mirrored the plasma concentration-time profile. The AUC0-τ for ELF and AM were 78.9 μg · h/ml and 169 μg · h/ml, respectively. The AUC0-τ ratios of ELF and AM to total plasma were 1.2 and 2.5, respectively. These ratios increased to 3.5 and 7.4, respectively, when unbound plasma was considered. These results are supportive of GSK1322322 as a potential antimicrobial agent for the treatment of lower respiratory tract bacterial infections caused by susceptible pathogens. (This study has been registered at ClinicalTrials.gov under registration number NCT01610388.).
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Lloyd AJ, Potter NJ, Fishwick CWG, Roper DI, Dowson CG. Adenosine tetraphosphoadenosine drives a continuous ATP-release assay for aminoacyl-tRNA synthetases and other adenylate-forming enzymes. ACS Chem Biol 2013; 8:2157-63. [PMID: 23898887 DOI: 10.1021/cb400248f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aminoacyl-tRNA synthetases are essential for the correct linkage of amino acids to cognate tRNAs to maintain the fidelity of protein synthesis. Tractable, continuous assays are valuable for characterizing the functions of synthetases and for their exploitation as drug targets. We have exploited the unexplored ability of these enzymes to consume adenosine tetraphosphoadenosine (diadenosine 5',5‴ P(1) P(4) tetraphosphate; Ap4A) and produce ATP to develop such an assay. We have used this assay to probe the stereoselectivity of isoleucyl-tRNA(Ile) and Valyl-tRNA(Val) synthetases and the impact of tRNA on editing by isoleucyl-tRNA(Ile) synthetase (IleRS) and to identify analogues of intermediates of these enzymes that might allow targeting of multiple synthetases. We further report the utility of Ap4A-based assays for identification of synthetase inhibitors with nanomolar to millimolar affinities. Finally, we demonstrate the broad application of Ap4A utilization with a continuous Ap4A-driven RNA ligase assay.
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Affiliation(s)
- Adrian J. Lloyd
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry,
West Midlands CV4 7AL, U.K
| | | | | | - David I. Roper
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry,
West Midlands CV4 7AL, U.K
| | - Christopher G. Dowson
- School of Life Sciences, University of Warwick, Gibbet Hill Road, Coventry,
West Midlands CV4 7AL, U.K
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44
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Maffioli SI. A Chemist's Survey of Different Antibiotic Classes. Antibiotics (Basel) 2013. [DOI: 10.1002/9783527659685.ch1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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45
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Clark RB, He M, Deng Y, Sun C, Chen CL, Hunt DK, O’Brien WJ, Fyfe C, Grossman TH, Sutcliffe JA, Achorn C, Hogan PC, Katz CE, Niu J, Zhang WY, Zhu Z, Ronn M, Xiao XY. Synthesis and Biological Evaluation of 8-Aminomethyltetracycline Derivatives as Novel Antibacterial Agents. J Med Chem 2013; 56:8112-38. [DOI: 10.1021/jm401211t] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Roger B. Clark
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Minsheng He
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Yonghong Deng
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Cuixiang Sun
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Chi-Li Chen
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Diana K. Hunt
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - William J. O’Brien
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Corey Fyfe
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Trudy H. Grossman
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Joyce A. Sutcliffe
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Catherine Achorn
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Philip C. Hogan
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Christopher E. Katz
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - John Niu
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Wu-Yan Zhang
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Zhijian Zhu
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Magnus Ronn
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
| | - Xiao-Yi Xiao
- Discovery Chemistry, ‡Microbiology, and §Process Chemistry R&D, Tetraphase Pharmaceuticals, Inc., 480 Arsenal Street, Watertown, Massachusetts 02472, United States
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Abstract
New antimicrobial agents are always needed to counteract the resistant pathogens that continue to be selected by current therapeutic regimens. This review provides a survey of known antimicrobial agents that were currently in clinical development in the fall of 2012 and spring of 2013. Data were collected from published literature primarily from 2010 to 2012, meeting abstracts (2011 to 2012), government websites, and company websites when appropriate. Compared to what was reported in previous surveys, a surprising number of new agents are currently in company pipelines, particularly in phase 3 clinical development. Familiar antibacterial classes of the quinolones, tetracyclines, oxazolidinones, glycopeptides, and cephalosporins are represented by entities with enhanced antimicrobial or pharmacological properties. More importantly, compounds of novel chemical structures targeting bacterial pathways not previously exploited are under development. Some of the most promising compounds include novel β-lactamase inhibitor combinations that target many multidrug-resistant Gram-negative bacteria, a critical medical need. Although new antimicrobial agents will continue to be needed to address increasing antibiotic resistance, there are novel agents in development to tackle at least some of the more worrisome pathogens in the current nosocomial setting.
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Affiliation(s)
| | - Karen Bush
- Indiana University, Bloomington, Indiana, USA
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47
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Butler MS, Blaskovich MA, Cooper MA. Antibiotics in the clinical pipeline in 2013. J Antibiot (Tokyo) 2013; 66:571-91. [PMID: 24002361 DOI: 10.1038/ja.2013.86] [Citation(s) in RCA: 309] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 07/31/2013] [Accepted: 08/02/2013] [Indexed: 12/17/2022]
Abstract
The continued emergence of multi-drug-resistant bacteria is a major public health concern. The identification and development of new antibiotics, especially those with new modes of action, is imperative to help treat these infections. This review lists the 22 new antibiotics launched since 2000 and details the two first-in-class antibiotics, fidaxomicin (1) and bedaquiline (2), launched in 2011 and 2012, respectively. The development status, mode of action, spectra of activity, historical discovery and origin of the drug pharmacophore (natural product, natural product derived, synthetic or protein/mammalian peptide) of the 49 compounds and 6 β-lactamase/β-lactam combinations in active clinical development are discussed, as well as compounds that have been discontinued from clinical development since 2011. New antibacterial pharmacophore templates are also reviewed and analyzed.
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Affiliation(s)
- Mark S Butler
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
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48
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Bassetti M, Merelli M, Temperoni C, Astilean A. New antibiotics for bad bugs: where are we? Ann Clin Microbiol Antimicrob 2013; 12:22. [PMID: 23984642 PMCID: PMC3846448 DOI: 10.1186/1476-0711-12-22] [Citation(s) in RCA: 264] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 08/25/2013] [Indexed: 01/05/2023] Open
Abstract
Bacterial resistance to antibiotics is growing up day by day in both community and hospital setting, with a significant impact on the mortality and morbidity rates and the financial burden that is associated. In the last two decades multi drug resistant microorganisms (both hospital- and community-acquired) challenged the scientific groups into developing new antimicrobial compounds that can provide safety in use according to the new regulation, good efficacy patterns, and low resistance profile. In this review we made an evaluation of present data regarding the new classes and the new molecules from already existing classes of antibiotics and the ongoing trends in antimicrobial development. Infectious Diseases Society of America (IDSA) supported a proGram, called “the ′10 × ´20′ initiative”, to develop ten new systemic antibacterial drugs within 2020. The microorganisms mainly involved in the resistance process, so called the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and enterobacteriaceae) were the main targets. In the era of antimicrobial resistance the new antimicrobial agents like fifth generation cephalosporins, carbapenems, monobactams, β-lactamases inhibitors, aminoglycosides, quinolones, oxazolidones, glycopeptides, and tetracyclines active against Gram-positive pathogens, like vancomycin-resistant S. aureus (VRSA) and MRSA, penicillin-resistant streptococci, and vancomycin resistant Enterococcus (VRE) but also against highly resistant Gram-negative organisms are more than welcome. Of these compounds some are already approved by official agencies, some are still in study, but the need of new antibiotics still does not cover the increasing prevalence of antibiotic-resistant bacterial infections. Therefore the management of antimicrobial resistance should also include fostering coordinated actions by all stakeholders, creating policy guidance, support for surveillance and technical assistance.
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Affiliation(s)
- Matteo Bassetti
- Infectious Diseases Division, Santa Maria Misercordia Hospital, Udine, Italy.
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Naderer OJ, Jones LS, Zhu J, Kurtinecz M, Dumont E. Safety, tolerability, and pharmacokinetics of oral and intravenous administration of GSK1322322, a peptide deformylase inhibitor. J Clin Pharmacol 2013; 53:1168-76. [PMID: 23907665 DOI: 10.1002/jcph.150] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 07/14/2013] [Indexed: 11/09/2022]
Abstract
GSK1322322 is the first in a new class of antibiotics that targets peptide deformylase (PDF), an essential bacterial enzyme required for protein maturation. This randomized, double-blind, placebo-controlled, eight-cohort phase I trial enrolled 62 healthy volunteers to assess safety, tolerability, and pharmacokinetic profiles of GSK1322322. GSK1322322 was administered as a single oral or intravenous (IV) dose, escalating from 500 to 3,000 mg or repeat IV doses escalating from 500 to 1,500 mg twice daily. Upon repeat IV administration, GSK1322322 exhibits linear pharmacokinetics over time upon repeat doses as shown by time-invariant pharmacokinetics. A dose-proportional increase in area under concentration-time curve was observed after single or repeat IV dosing, whereas clearance at steady state remained generally unchanged across doses. There was minimal accumulation of GSK1322322 after repeat IV twice-daily administration. After oral tablet doses of GSK1322322 1,000 and 1,500 mg, absolute bioavailability was 69% and 56%, respectively. GSK1322322 administration at single and repeat IV doses and at supratherapeutic single IV doses of 2,000 and 3,000 mg was associated with mild-to-moderate drug-related adverse events. On the basis of the pharmacokinetics and tolerability demonstrated in this study, GSK1322322 has the potential to become the first-in-class PDF inhibitor for clinical use.
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50
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Skrupky LP, Tellor BR, Mazuski JE. Current strategies for the treatment of complicated intraabdominal infections. Expert Opin Pharmacother 2013; 14:1933-47. [DOI: 10.1517/14656566.2013.821109] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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