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Heidtmann CV, Fejer AR, Stærk K, Pedersen M, Asmussen MG, Hertz FB, Prabhala BK, Frimodt-Møller N, Klitgaard JK, Andersen TE, Nielsen CU, Nielsen P. Hit-to-Lead Identification and Validation of a Triaromatic Pleuromutilin Antibiotic Candidate. J Med Chem 2024; 67:3692-3710. [PMID: 38385364 DOI: 10.1021/acs.jmedchem.3c02153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Herein, we report the hit-to-lead identification of a drug-like pleuromutilin conjugate 16, based on a triaromatic hit reported in 2020. The lead arose as the clear candidate from a hit-optimization campaign in which Gram-positive antibacterial activity, solubility, and P-gp affinity were optimized. Conjugate 16 was extensively evaluated for its in vitro ADMET performance which, apart from solubility, was overall on par with lefamulin. This evaluation included Caco-2 cell permeability, plasma protein binding, hERG inhibition, cytotoxicity, metabolism in microsomes and CYP3A4, resistance induction, and time-kill kinetics. Intravenous pharmacokinetics of 16 proved satisfactory in both mice and pigs; however, oral bioavailability was limited likely due to insufficient solubility. The in vivo efficacy was evaluated in mice, systemically infected with Staphylococcus aureus, where 16 showed rapid reduction in blood bacteriaemia. Through our comprehensive studies, lead 16 has emerged as a highly promising and safe antibiotic candidate for the treatment of Gram-positive bacterial infections.
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Affiliation(s)
- Christoffer V Heidtmann
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Andreas R Fejer
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Kristian Stærk
- Department of Clinical Research, Research Unit of Clinical Microbiology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Maria Pedersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Marco G Asmussen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Frederik B Hertz
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark
| | - Bala K Prabhala
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Niels Frimodt-Møller
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, DK-2100 Copenhagen, Denmark
| | - Janne K Klitgaard
- Department of Clinical Research, Research Unit of Clinical Microbiology, University of Southern Denmark, DK-5230 Odense M, Denmark
- Department of Biochemistry and Molecular Biology, Research Unit of Molecular Microbiology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Thomas E Andersen
- Department of Clinical Research, Research Unit of Clinical Microbiology, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Carsten U Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
| | - Poul Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense M, Denmark
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2
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Marina VI, Bidzhieva M, Tereshchenkov AG, Orekhov D, Sagitova VE, Sumbatyan NV, Tashlitsky VN, Ferberg AS, Maviza TP, Kasatsky P, Tolicheva O, Paleskava A, Polshakov VI, Osterman IA, Dontsova OA, Konevega AL, Sergiev PV. An easy tool to monitor the elemental steps of in vitro translation via gel electrophoresis of fluorescently labeled small peptides. RNA (NEW YORK, N.Y.) 2024; 30:298-307. [PMID: 38164606 PMCID: PMC10870375 DOI: 10.1261/rna.079766.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 11/22/2023] [Indexed: 01/03/2024]
Abstract
Several methods are available to visualize and assess the kinetics and efficiency of elemental steps of protein biosynthesis. However, each of these methods has its own limitations. Here, we present a novel, simple and convenient tool for monitoring stepwise in vitro translation initiated by BODIPY-Met-tRNA. Synthesis and release of very short, 1-7 amino acids, BODIPY-labeled peptides, can be monitored using urea-polyacrylamide gel electrophoresis. Very short BODIPY-labeled oligopeptides might be resolved this way, in contrast to widely used Tris-tricine gel electrophoresis, which is suitable to separate peptides larger than 1 kDa. The method described in this manuscript allows one to monitor the steps of translation initiation, peptide transfer, translocation, and termination as well as their inhibition at an unprecedented single amino acid resolution.
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Affiliation(s)
- Valeriya I Marina
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Skolkovo 121205, Russia
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Medina Bidzhieva
- Molecular and Radiation Biophysics Division, Petersburg Nuclear Physics Institute named by B.P. Konstantinov of NRC "Kurchatov Institute," Gatchina 188300, Russia
- Institute of Biomedical Systems and Biotechnologies, Peter the Great St. Petersburg Polytechnic University, Saint Petersburg 195251, Russia
| | - Andrey G Tereshchenkov
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Dmitry Orekhov
- R&D Department, VIC Animal Health, Severny, Belgorod Region 308519, Russia
| | | | - Nataliya V Sumbatyan
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Vadim N Tashlitsky
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Artem S Ferberg
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Tinashe P Maviza
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Skolkovo 121205, Russia
| | - Pavel Kasatsky
- Molecular and Radiation Biophysics Division, Petersburg Nuclear Physics Institute named by B.P. Konstantinov of NRC "Kurchatov Institute," Gatchina 188300, Russia
| | - Olga Tolicheva
- Molecular and Radiation Biophysics Division, Petersburg Nuclear Physics Institute named by B.P. Konstantinov of NRC "Kurchatov Institute," Gatchina 188300, Russia
| | - Alena Paleskava
- Molecular and Radiation Biophysics Division, Petersburg Nuclear Physics Institute named by B.P. Konstantinov of NRC "Kurchatov Institute," Gatchina 188300, Russia
- Institute of Biomedical Systems and Biotechnologies, Peter the Great St. Petersburg Polytechnic University, Saint Petersburg 195251, Russia
| | - Vladimir I Polshakov
- Faculty of Fundamental Medicine, Lomonosov Moscow State University Moscow, Moscow 119991, Russia
| | - Ilya A Osterman
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Skolkovo 121205, Russia
| | - Olga A Dontsova
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Skolkovo 121205, Russia
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119991, Russia
- Department of Functioning of Living Systems, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia
| | - Andrey L Konevega
- Molecular and Radiation Biophysics Division, Petersburg Nuclear Physics Institute named by B.P. Konstantinov of NRC "Kurchatov Institute," Gatchina 188300, Russia
- Institute of Biomedical Systems and Biotechnologies, Peter the Great St. Petersburg Polytechnic University, Saint Petersburg 195251, Russia
| | - Petr V Sergiev
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Skolkovo 121205, Russia
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119991, Russia
- Institute of Functional Genomics, Lomonosov Moscow State University, Moscow 119991, Russia
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3
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Zhou Y, Yi Y, Yang J, Zhang H, Liu Q, Wang S, Pu W, Shang R. Anti-methicillin-resistant Staphylococcus aureus activity and safety evaluation of 14-O-[(5-ethoxycarbonyl-4,6-dimethylpyrimidine-2-yl) thioacetyl] mutilin (EDT). Sci Rep 2023; 13:15267. [PMID: 37709940 PMCID: PMC10502144 DOI: 10.1038/s41598-023-42621-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 09/12/2023] [Indexed: 09/16/2023] Open
Abstract
Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have threated the public health worldwide, which emphasizes the urgent need for new drugs with novel mechanism of actions. 14-O-[(5-ethoxycarbonyl-4,6-dimethylpyrimidine-2-yl) thioacetyl] mutilin (EDT) is a pleuromutilin compound with high activity against several Gram-positive bacteria in vitro and in vivo. This study aimed to verifying the potential anti-MRSA activity and evaluating the safety of EDT. In in vitro antibacterial activity assays, EDT exhibited potent antibacterial activity against MRSA isolated from clinic (minimum inhibitory concentration = 0.0313-0.125 μg/mL), increased post-antibiotic effect (PAE) values and limited potential for the development of resistance. Docking model and green fluorescent protein (GFP) inhibition assay further elucidated the higher antibacterial activities of EDT via mechanism of action. In safety evaluation, EDT exhibited low cytotoxic effect and acute oral toxicity in mice and avoided to significantly increase the number of revertant colonies of six tested strains in the Ames study. Furthermore, EDT displayed a moderate inhibitory effect on CYP3A4 and moderate stability in mouse and human liver microsomes, providing a promising agent for the development of new antimicrobial candidate.
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Affiliation(s)
- Yuhang Zhou
- Key Laboratory of New Animal Drug Project, Gansu Province/Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs/Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, No. 335, Qilihe District, Lanzhou, 730050, People's Republic of China
| | - Yunpeng Yi
- Shandong Provincial Animal and Poultry Green Health Products Creation Engineering Laboratory, Institute of Poultry Science, Shandong Academy of Agricultural Science, Jinan, 250023, People's Republic of China
| | - Jing Yang
- Gansu Analysis and Research Center, Lanzhou, 730000, People's Republic of China
| | - Hongjuan Zhang
- Key Laboratory of New Animal Drug Project, Gansu Province/Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs/Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, No. 335, Qilihe District, Lanzhou, 730050, People's Republic of China
| | - Qinqin Liu
- Key Laboratory of New Animal Drug Project, Gansu Province/Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs/Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, No. 335, Qilihe District, Lanzhou, 730050, People's Republic of China
| | - Shengyi Wang
- Key Laboratory of New Animal Drug Project, Gansu Province/Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs/Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, No. 335, Qilihe District, Lanzhou, 730050, People's Republic of China
| | - Wanxia Pu
- Key Laboratory of New Animal Drug Project, Gansu Province/Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs/Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, No. 335, Qilihe District, Lanzhou, 730050, People's Republic of China
| | - Ruofeng Shang
- Key Laboratory of New Animal Drug Project, Gansu Province/Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs/Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, No. 335, Qilihe District, Lanzhou, 730050, People's Republic of China.
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4
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Xia J, Xin L, Li J, Tian L, Wu K, Zhang S, Yan W, Li H, Zhao Q, Liang C. Discovery of Quaternized Pyridine-Thiazole-Pleuromutilin Derivatives with Broad-Spectrum Antibacterial and Potent Anti-MRSA Activity. J Med Chem 2023; 66:5061-5078. [PMID: 37051724 DOI: 10.1021/acs.jmedchem.2c02135] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The quaternization of compounds has emerged as a promising molecular design strategy for the development of antibiotics. Herein, we report the design, synthesis, antibacterial activities, and structure-activity relationships of a series of novel pleuromutilin derivatives containing a quaternary amine C-14 side chain. Most of these derivatives exhibited broad-spectrum antibacterial activity against the tested bacteria. 10b was the most effective antibacterial agent that displayed excellent antibacterial activity against five clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates, remarkable antimycoplasma activity, rapid bactericidal effects, and a strong ability to damage bacterial biofilms. Further mechanistic studies indicated that 10b destroyed bacterial cell membranes to exert its antibacterial effects. Moreover, 10b exhibited high survival protection and potent in vivo antibacterial efficacy (ED50 = 4.94 mg/kg) in a mouse model of systemic MRSA infection. These findings suggest that 10b is a promising candidate for the treatment of multi-drug-resistant infectious diseases, especially MRSA infections.
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Affiliation(s)
- Juan Xia
- Laboratory of Hematologic Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang 524001, P. R. China
| | - Liang Xin
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Jingyi Li
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Lei Tian
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Kangxiong Wu
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Shaojun Zhang
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Wenjing Yan
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Han Li
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Qianqian Zhao
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
| | - Chengyuan Liang
- School of Biology and Medicine, Shaanxi University of Science & Technology, Xi’an 710021, P. R. China
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5
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Guo C, Dai H, Zhang M, Liao H, Zhang R, Chen B, Han J, Liu H. Molecular networking assisted discovery and combinatorial biosynthesis of new antimicrobial pleuromutilins. Eur J Med Chem 2022; 243:114713. [DOI: 10.1016/j.ejmech.2022.114713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/22/2022] [Accepted: 08/22/2022] [Indexed: 11/04/2022]
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6
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Rivera-Chávez J, Ceapă CD, Figueroa M. Biological Dark Matter Exploration using Data Mining for the Discovery of Antimicrobial Natural Products. PLANTA MEDICA 2022; 88:702-720. [PMID: 35697058 DOI: 10.1055/a-1795-0562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The discovery of novel antimicrobials has significantly slowed down over the last three decades. At the same time, humans rely increasingly on antimicrobials because of the progressive antimicrobial resistance in medical practices, human communities, and the environment. Data mining is currently considered a promising option in the discovery of new antibiotics. Some of the advantages of data mining are the ability to predict chemical structures from sequence data, anticipation of the presence of novel metabolites, the understanding of gene evolution, and the corroboration of data from multiple omics technologies. This review analyzes the state-of-the-art for data mining in the fields of bacteria, fungi, and plant genomic data, as well as metabologenomics. It also summarizes some of the most recent research accomplishments in the field, all pinpointing to innovation through uncovering and implementing the next generation of antimicrobials.
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Affiliation(s)
- José Rivera-Chávez
- Instituto de Química, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Corina-Diana Ceapă
- Instituto de Química, Universidad Nacional Autónoma de México, Ciudad de México, México
| | - Mario Figueroa
- Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, México
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7
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Wang X, Wang R, Zhang ZS, Zhang GY, Jin Z, Shen R, Du D, Tang YZ. Semisynthetic pleuromutilin antimicrobials with therapeutic potential against methicillin-resistant Staphylococcus aureus by targeting 50S ribosomal subunit. Eur J Med Chem 2022; 237:114341. [PMID: 35430480 DOI: 10.1016/j.ejmech.2022.114341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/17/2022] [Accepted: 03/31/2022] [Indexed: 11/04/2022]
Abstract
A series of pleuromutilin analogs with a substituted 1,2,4-triazole were designed, synthesized and assessed for their in vitro and in vivo antibacterial activity. Initially, the MIC of the synthesized derivatives against five strains of Staphylococcus aureus (MRSA ATCC 43300, S. aureus ATCC 29213, clinical isolation of S. aureus AD3, S. aureus 144 and S. aureus SA17) were tested by the broth dilution method. Compounds 30a, 31b and 32a were the most active antibacterial agents in vitro against MRSA (MIC = 0.0625 μg/mL). The results of the time-kill curves showed that compounds 30a and 32a could reduce the amount of MRSA in vitro quickly (-7.70 log10 CFU/mL and -7.10 log10 CFU/mL reduction). In the experiment to further evaluate the in vivo antibacterial activity of compound 30a against MRSA, compound 30a (-1.71 log10 CFU/g) was effective in reducing MRSA load in thigh infected mice. Compound 30a (survival rate was 50%) displayed superior in vivo efficacy to that of tiamulin (survival rate was 30%) in the mouse systemic model. The results of further pharmacokinetic studies on compound 30a showed that the half-life (t1/2), clearance rate (Cl) and the area under the plasma concentration time curve (AUC0→∞) of compound 30a were 0.37 h, 5.43 L/h/kg and 1.84 μg h/mL, respectively. After affinity measurement by surface plasmon resonance (SPR), compound 30a exhibited high affinity with the 50S ribosome, with KD value of 1.95 × 10-6 M. Furthermore, the results of molecular docking studies revealed that compound 30a was successfully localized inside the binding pocket of 50S ribosomal subunit (ΔGb = -9.40 kcal/mol). Meanwhile, most of these compounds had no significant inhibitory effect on RAW 264.7 cells and 16HBE cells at the concentration of 8 μg/mL. The obtained outcomes showed that compound 30a could be utilized as an encouraging perspective in the development of a new therapeutic candidate for bacterial infection.
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Affiliation(s)
- Xiao Wang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China; Cancer Research Center, Department of Stomatology, School of Medicine, Xiamen University, Xiamen, Fujian, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Rui Wang
- Cancer Research Center, Department of Stomatology, School of Medicine, Xiamen University, Xiamen, Fujian, China; Fujian Provincial Key Laboratory of Reproductive Health Research, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Zhao-Sheng Zhang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Guang-Yu Zhang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Zhen Jin
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Rong Shen
- Cancer Research Center, Department of Stomatology, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Dan Du
- Cancer Research Center, Department of Stomatology, School of Medicine, Xiamen University, Xiamen, Fujian, China; Fujian Provincial Key Laboratory of Reproductive Health Research, School of Medicine, Xiamen University, Xiamen, Fujian, China.
| | - You-Zhi Tang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
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8
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Retapamulin: Current Status and Future Perspectives. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2021. [DOI: 10.5812/archcid.114970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
: Retapamulin is one of the antibiotics recently developed semi-synthetically to inhibit protein synthesis in a specific manner different from other antibiotics. This pleuromutilin derivative shows magnificent anti-bacterial activity in Gram-positive pathogens, especially Staphylococcus aureus and Streptococcus pyogenes, and now it is available in ointment formulations (1%) for clinical use with negligible side effects. Despite the low potential for resistance development, antimicrobial susceptibility rates are significantly high. This is especially important when the prevalence of mupirocin-resistant strains is increasing, and the need for new alternatives is urgent. Unfortunately, due to its oxidation by cytochrome p450, this drug cannot be used systemically. However, another pleuromutilin derivative with systemic use, lefamulin, was approved in August 2019 by the US Food and Drug Administration. In addition to pharmacokinetic features, financial issues are also barriers to consider in the progress of new antimicrobials. In this review, we attempt to take a brief look at the derivatives usable in humans and explore their structures, action mode, metabolism, possible ways of resistance, resistance rates, and their clinical use to explain and highlight the valuable points of these antibiotics.
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9
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Zhang Z, Zhang ZS, Wang X, Xi GL, Jin Z, Tang YZ. A click chemistry approach to pleuromutilin derivatives, evaluation of anti-MRSA activity and elucidation of binding mode by surface plasmon resonance and molecular docking. J Enzyme Inhib Med Chem 2021; 36:2087-2103. [PMID: 34823417 PMCID: PMC8635623 DOI: 10.1080/14756366.2021.1977931] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 08/31/2021] [Accepted: 09/02/2021] [Indexed: 10/29/2022] Open
Abstract
Novel series of pleuromutilin analogs containing substituted 1,2,3-triazole moieties were designed, synthesised and assessed for their in vitro antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA). Initially, the in vitro antibacterial activities of these derivatives against 4 strains of S. aureus (MRSA ATCC 43300, ATCC 29213, AD3, and 144) were tested by the broth dilution method. Most of the synthesised pleuromutilin analogs displayed potent activities. Among them, compounds 50, 62, and 64 (MIC = 0.5∼1 µg/mL) showed the most effective antibacterial activity and their anti-MRSA activity were further studied by the time-killing kinetics approach. Binding mode investigations by surface plasmon resonance (SPR) with 50S ribosome revealed that the selected compounds all showed obvious affinity for 50S ribosome (KD = 2.32 × 10-8∼5.10 × 10-5 M). Subsequently, the binding of compounds 50 and 64 to the 50S ribosome was further investigated by molecular modelling. Compound 50 had a superior docking mode with 50S ribosome, and the binding free energy of compound 50 was calculated to be -12.0 kcal/mol.
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Affiliation(s)
- Zhe Zhang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Zhao-Sheng Zhang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Xiao Wang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Gao-Lei Xi
- Technology Center for China Tobacco Henan Industrial Limited Company, Zhengzhou, China
| | - Zhen Jin
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - You-Zhi Tang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
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10
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Shirokikh NE. Translation complex stabilization on messenger RNA and footprint profiling to study the RNA responses and dynamics of protein biosynthesis in the cells. Crit Rev Biochem Mol Biol 2021; 57:261-304. [PMID: 34852690 DOI: 10.1080/10409238.2021.2006599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
During protein biosynthesis, ribosomes bind to messenger (m)RNA, locate its protein-coding information, and translate the nucleotide triplets sequentially as codons into the corresponding sequence of amino acids, forming proteins. Non-coding mRNA features, such as 5' and 3' untranslated regions (UTRs), start sites or stop codons of different efficiency, stretches of slower or faster code and nascent polypeptide interactions can alter the translation rates transcript-wise. Most of the homeostatic and signal response pathways of the cells converge on individual mRNA control, as well as alter the global translation output. Among the multitude of approaches to study translational control, one of the most powerful is to infer the locations of translational complexes on mRNA based on the mRNA fragments protected by these complexes from endonucleolytic hydrolysis, or footprints. Translation complex profiling by high-throughput sequencing of the footprints allows to quantify the transcript-wise, as well as global, alterations of translation, and uncover the underlying control mechanisms by attributing footprint locations and sizes to different configurations of the translational complexes. The accuracy of all footprint profiling approaches critically depends on the fidelity of footprint generation and many methods have emerged to preserve certain or multiple configurations of the translational complexes, often in challenging biological material. In this review, a systematic summary of approaches to stabilize translational complexes on mRNA for footprinting is presented and major findings are discussed. Future directions of translation footprint profiling are outlined, focusing on the fidelity and accuracy of inference of the native in vivo translation complex distribution on mRNA.
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Affiliation(s)
- Nikolay E Shirokikh
- Division of Genome Sciences and Cancer, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
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11
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Bartholomäus A, Kolte B, Mustafayeva A, Goebel I, Fuchs S, Benndorf D, Engelmann S, Ignatova Z. smORFer: a modular algorithm to detect small ORFs in prokaryotes. Nucleic Acids Res 2021; 49:e89. [PMID: 34125903 PMCID: PMC8421149 DOI: 10.1093/nar/gkab477] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 04/29/2021] [Accepted: 05/18/2021] [Indexed: 11/15/2022] Open
Abstract
Emerging evidence places small proteins (≤50 amino acids) more centrally in physiological processes. Yet, their functional identification and the systematic genome annotation of their cognate small open-reading frames (smORFs) remains challenging both experimentally and computationally. Ribosome profiling or Ribo-Seq (that is a deep sequencing of ribosome-protected fragments) enables detecting of actively translated open-reading frames (ORFs) and empirical annotation of coding sequences (CDSs) using the in-register translation pattern that is characteristic for genuinely translating ribosomes. Multiple identifiers of ORFs that use the 3-nt periodicity in Ribo-Seq data sets have been successful in eukaryotic smORF annotation. They have difficulties evaluating prokaryotic genomes due to the unique architecture (e.g. polycistronic messages, overlapping ORFs, leaderless translation, non-canonical initiation etc.). Here, we present a new algorithm, smORFer, which performs with high accuracy in prokaryotic organisms in detecting putative smORFs. The unique feature of smORFer is that it uses an integrated approach and considers structural features of the genetic sequence along with in-frame translation and uses Fourier transform to convert these parameters into a measurable score to faithfully select smORFs. The algorithm is executed in a modular way, and dependent on the data available for a particular organism, different modules can be selected for smORF search.
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Affiliation(s)
- Alexander Bartholomäus
- GFZ German Research Centre for Geosciences, Section Geomicrobiology, 14473 Potsdam, Germany.,Inst. Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Baban Kolte
- Inst. Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | - Ayten Mustafayeva
- Helmholtz Center for Infection Research, Microbial Proteomics, 38124 Braunschweig, Germany.,Inst. Microbiology, TU Braunschweig, Braunschweig, Germany
| | - Ingrid Goebel
- Inst. Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 20146 Hamburg, Germany
| | | | - Dirk Benndorf
- Otto von Guericke University, Bioprocess Engineering, 39106 Magdeburg, Germany.,Max Planck Institute for Dynamics of Complex Technical Systems, Bioprocess Engineering, 39106 Magdeburg, Germany
| | - Susanne Engelmann
- Helmholtz Center for Infection Research, Microbial Proteomics, 38124 Braunschweig, Germany.,Inst. Microbiology, TU Braunschweig, Braunschweig, Germany
| | - Zoya Ignatova
- Inst. Biochemistry and Molecular Biology, Department of Chemistry, University of Hamburg, 20146 Hamburg, Germany
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12
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de Mattos-Shipley KMJ, Foster GD, Bailey AM. Cprp-An Unusual, Repetitive Protein Which Impacts Pleuromutilin Biosynthesis in the Basidiomycete Clitopilus passeckerianus. FRONTIERS IN FUNGAL BIOLOGY 2021; 2:655323. [PMID: 37744150 PMCID: PMC10512284 DOI: 10.3389/ffunb.2021.655323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 03/04/2021] [Indexed: 09/26/2023]
Abstract
Interrogation of an EST database for Clitopilus passeckerianus identified a putative homolog to the unusual stress response gene from yeast; ddr48, as being upregulated under pleuromutilin production conditions. Silencing of this gene, named cprp, produced a population of transformants which demonstrated significantly reduced pleuromutilin production. Attempts to complement a Saccharomyces cerevisiae ddr48 mutant strain (strain Y16748) with cprp were hampered by the lack of a clearly identifiable mutant phenotype, but interestingly, overexpression of either ddr48 or cprp in S. cerevisiae Y16748 led to a conspicuous and comparable reduction in growth rate. This observation, combined with the known role of DDR48 proteins from a range of fungal species in nutrient starvation and stress responses, raises the possibility that this family of proteins plays a role in triggering oligotrophic growth. Localization studies via the production of a Cprp:GFP fusion protein in C. passeckerianus showed clear localization adjacent to the hyphal septa and, to a lesser extent, cell walls, which is consistent with the identification of DDR48 as a cell wall-associated protein in various yeast species. To our knowledge this is the first study demonstrating that a DDR48-like protein plays a role in the regulation of a secondary metabolite, and represents the first DDR48-like protein from a basidiomycete. Potential homologs can be identified across much of the Dikarya, suggesting that this unusual protein may play a central role in regulating both primary and secondary metabolism in fungi.
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Affiliation(s)
| | | | - Andy M. Bailey
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
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13
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LoVecchio F, Schranz J, Alexander E, Mariano D, Meads A, Sandrock C, Moran GJ, Giordano PA. Oral 5-Day Lefamulin for Outpatient Management of Community-Acquired Bacterial Pneumonia: Post-hoc Analysis of the Lefamulin Evaluation Against Pneumonia (LEAP) 2 Trial. J Emerg Med 2021; 60:781-792. [PMID: 33731270 DOI: 10.1016/j.jemermed.2021.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/29/2020] [Accepted: 02/06/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Safe and effective oral antibiotics are needed for outpatient management of moderate to severe community-acquired bacterial pneumonia (CABP). OBJECTIVE We describe a post-hoc analysis of adults with CABP managed as outpatients from the Lefamulin Evaluation Against Pneumonia (LEAP) 2 double-blind, noninferiority, phase 3 clinical trial. METHODS LEAP 2 compared the efficacy and safety of oral lefamulin 600 mg every 12 h (5 days) vs. oral moxifloxacin 400 mg every 24 h (7 days) in adults (inpatients and outpatients) with Pneumonia Outcomes Research Team (PORT) risk classes II‒IV. RESULTS Overall, 41% (151 of 368) of patients receiving lefamulin and 43% (159 of 368) of patients receiving moxifloxacin started treatment as outpatients-44% and 40%, respectively, were PORT risk class III/IV, and 21% in both groups had CURB-65 scores of 2‒3. Early clinical response (at 96 ± 24 h) and investigator assessment of clinical response success rates at test of cure (5‒10 days after last study drug dose) were high and similar in both groups among all (lefamulin, 91% vs. moxifloxacin, 89‒90%), PORT risk class III/IV (89‒91% vs. 88‒91%), and CURB-65 score 2‒3 (87‒90% vs. 82‒88%) outpatients. Few outpatients (lefamulin, 2.6%; moxifloxacin, 2.5%) discontinued the study drug because of treatment-emergent adverse events (TEAEs). No outpatient in the lefamulin group was hospitalized for a TEAE, compared with 5 patients (3%), including two deaths, in the moxifloxacin group. CONCLUSIONS These data suggest that 5 days of oral lefamulin can be given in lieu of fluoroquinolones for outpatient treatment of adults with CABP and PORT risk class III/IV or CURB-65 scores of 2‒3.
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Affiliation(s)
- Frank LoVecchio
- ASU, U of AZ, Creighton, Valleywise Medical Center, University of Arizona, Phoenix, Arizona
| | | | | | - David Mariano
- Nabriva Therapeutics US, Inc., King of Prussia, Pennsylvania
| | - Andrew Meads
- Nabriva Therapeutics US, Inc., King of Prussia, Pennsylvania
| | | | | | - Philip A Giordano
- Department of Emergency Medicine, Orlando Regional Medical Center, Orlando, Florida
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14
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Bhattarai K, Bhattarai K, Kabir ME, Bastola R, Baral B. Fungal natural products galaxy: Biochemistry and molecular genetics toward blockbuster drugs discovery. ADVANCES IN GENETICS 2021; 107:193-284. [PMID: 33641747 DOI: 10.1016/bs.adgen.2020.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Secondary metabolites synthesized by fungi have become a precious source of inspiration for the design of novel drugs. Indeed, fungi are prolific producers of fascinating, diverse, structurally complex, and low-molecular-mass natural products with high therapeutic leads, such as novel antimicrobial compounds, anticancer compounds, immunosuppressive agents, among others. Given that these microorganisms possess the extraordinary capacity to secrete diverse chemical scaffolds, they have been highly exploited by the giant pharma companies to generate small molecules. This has been made possible because the isolation of metabolites from fungal natural sources is feasible and surpasses the organic synthesis of compounds, which otherwise remains a significant bottleneck in the drug discovery process. Here in this comprehensive review, we have discussed recent studies on different fungi (pathogenic, non-pathogenic, commensal, and endophytic/symbiotic) from different habitats (terrestrial and marines), the specialized metabolites they biosynthesize, and the drugs derived from these specialized metabolites. Moreover, we have unveiled the logic behind the biosynthesis of vital chemical scaffolds, such as NRPS, PKS, PKS-NRPS hybrid, RiPPS, terpenoids, indole alkaloids, and their genetic mechanisms. Besides, we have provided a glimpse of the concept behind mycotoxins, virulence factor, and host immune response based on fungal infections.
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Affiliation(s)
- Keshab Bhattarai
- Pharmaceutical Institute, Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany
| | - Keshab Bhattarai
- Central Department of Chemistry, Tribhuvan University, Kirtipur, Kathmandu, Nepal
| | - Md Ehsanul Kabir
- Animal Health Research Division, Bangladesh Livestock Research Institute, Savar, Dhaka, Bangladesh
| | - Rina Bastola
- Spinal Cord Injury Association-Nepal (SCIAN), Pokhara, Nepal
| | - Bikash Baral
- Department of Biochemistry, University of Turku, Turku, Finland.
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15
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Abstract
Topical antibacterials are commonly used for superficial pyodermas such as impetigo and treatment or prevention of infections following minor cuts, abrasions, burns, and surgical wounds. Several antibiotics and antiseptics are available for use in different indications. One of the major uses of topical antibacterials is acne in which benzoyl peroxide is the drug of the first choice either singly or in combination with antibiotics or retinoids. Mupirocin and fusidic acid are the two most commonly used antibiotics for the treatment of superficial pyodermas and eradication of staphylococcal carrier state. Bacterial resistance to topical antibiotics is a growing concern and topical antiseptics such as gentian violet are getting renewed interest as alternatives. Incidence of contact dermatitis is a limiting factor for the use of several topical antibacterials. Although many botanical products have demonstrated in vitro activities against skin pathogens, their clinical utilities remain to be established by good-quality clinical trials.
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Affiliation(s)
- Debabrata Bandyopadhyay
- Department of Dermatology, Venereology, and Leprosy, Medical College and Hospitals, Kolkata, 88, College Street, Kolkata, West Bengal, India
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16
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Heidtmann CV, Voukia F, Hansen LN, Sørensen SH, Urlund B, Nielsen S, Pedersen M, Kelawi N, Andersen BN, Pedersen M, Reinholdt P, Kongsted J, Nielsen CU, Klitgaard JK, Nielsen P. Discovery of a Potent Adenine-Benzyltriazolo-Pleuromutilin Conjugate with Pronounced Antibacterial Activity against MRSA. J Med Chem 2020; 63:15693-15708. [PMID: 33325700 DOI: 10.1021/acs.jmedchem.0c01328] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Conjugation of pleuromutilin is an attractive strategy for the development of novel antibiotics and the fight against multiresistant bacteria as the class is associated with low rates of resistance and cross-resistance development. Herein, the preparation of 35 novel (+)-pleuromutilin conjugates is reported. Their design was based on a synthetically more efficient benzyl adaption of a potent lead but still relied on the Cu(I)-catalyzed alkyne-azide [3 + 2] cycloaddition for conjugation onto pleuromutilin. Their antibacterial activity was evaluated against the multiresistant Staphylococcus aureus strain USA300 for which they displayed moderate to excellent activity. Compound 35, bearing a para-benzyladenine substituent, proved particularly potent against USA300 and additional strains of MRSA and displayed as importantly no cytotoxicity in four mammalian cell lines. Structure-activity relationship analysis revealed that the purine 6-amino is essential for high potency, likely because of strong hydrogen bonding with the RNA backbone of C2469, as suggested by a molecular model based on the MM-GBSA approach.
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Affiliation(s)
- Christoffer V Heidtmann
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Faidra Voukia
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Louise N Hansen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Stine H Sørensen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Brian Urlund
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Salli Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Mona Pedersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Noor Kelawi
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Brian N Andersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Maria Pedersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Peter Reinholdt
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Jacob Kongsted
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Carsten U Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Janne K Klitgaard
- Department of Biochemistry and Molecular Biology, Research Unit of Molecular Microbiology, University of Southern Denmark, 5230 Odense M, Denmark
- Institute of Clinical Research, Research Unit of Clinical Microbiology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Poul Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
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17
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Fostier CR, Monlezun L, Ousalem F, Singh S, Hunt JF, Boël G. ABC-F translation factors: from antibiotic resistance to immune response. FEBS Lett 2020; 595:675-706. [PMID: 33135152 DOI: 10.1002/1873-3468.13984] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 12/24/2022]
Abstract
Energy-dependent translational throttle A (EttA) from Escherichia coli is a paradigmatic ABC-F protein that controls the first step in polypeptide elongation on the ribosome according to the cellular energy status. Biochemical and structural studies have established that ABC-F proteins generally function as translation factors that modulate the conformation of the peptidyl transferase center upon binding to the ribosomal tRNA exit site. These factors, present in both prokaryotes and eukaryotes but not in archaea, use related molecular mechanisms to modulate protein synthesis for heterogenous purposes, ranging from antibiotic resistance and rescue of stalled ribosomes to modulation of the mammalian immune response. Here, we review the canonical studies characterizing the phylogeny, regulation, ribosome interactions, and mechanisms of action of the bacterial ABC-F proteins, and discuss the implications of these studies for the molecular function of eukaryotic ABC-F proteins, including the three human family members.
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Affiliation(s)
- Corentin R Fostier
- UMR 8261, CNRS, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
| | - Laura Monlezun
- UMR 8261, CNRS, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
| | - Farès Ousalem
- UMR 8261, CNRS, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
| | - Shikha Singh
- Department of Biological Sciences, 702A Sherman Fairchild Center, Columbia University, New York, NY, USA
| | - John F Hunt
- Department of Biological Sciences, 702A Sherman Fairchild Center, Columbia University, New York, NY, USA
| | - Grégory Boël
- UMR 8261, CNRS, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
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18
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Chniba I, Boujemaa S, Mardassi BBA, Ben Abdelmoumen Mardassi B. Clonal dissemination of antibiotic resistance among Tunisian Mycoplasma gallisepticum isolates as revealed by gene-targeted sequencing analysis. Avian Dis 2020; 65:446278. [PMID: 33057595 DOI: 10.1637/aviandiseases-d-20-00080r1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 11/05/2022]
Abstract
SummaryTo date, very little is known about avian mycoplasma infections in Tunisia. Mycoplasma gallisepticum is one of the most economically significant pathogen for poultry in Tunisia and worldwide. Based on the paucity of data regarding the genetic profiles and antibacterial behavior of M. gallisepticum strains in Tunisia, the present study was conducted. Genetic typing and phylogenetic relationships of 40 M. gallisepticum strains (20 Tunisian isolates, 19 international strains collection, and S6 reference strain) were investigated by gene-targeted sequencing (GTS) using 4 loci ( pvpA , mgc2 , vlhA and the InterGenic Spacer Region (IGSR) between the 16S and the 23S rRNA genes). GTS reveals 12 STs that were found to spread over 2 clonal complexes (CC) and 5 singletons.Emergence of enrofloxacin and spiramycin resistance among M. gallisepticum local isolates have been revealed using the broth microdilution method. Causal mutations have been identified by sequencing the quinolone-resistance determining region (QRDR) and domain II and V of 23S rRNA as well as the rplD and rplV genes for enrofloxacine- and macrolide-resistant isolates, respectively. The emersion of antibiotic resistance to enrofloxacin and spiramycin has been identified as being related to a distinctive clonal complex formed by 4 different STs (ST2, ST3, ST4 and ST5) which would suggest that this phenotype was clonally disseminated.
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Affiliation(s)
- Imen Chniba
- Group of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, Université de Tunis El Manar, 13, Place Pasteur, BP 74, 1002, Tunis Belvédère, Tunisia
| | - Safa Boujemaa
- Group of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, Université de Tunis El Manar, 13, Place Pasteur, BP 74, 1002, Tunis Belvédère, Tunisia
| | - Boutheina Ben Abdelmoumen Mardassi
- Group of Mycoplasmas, Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development, Institut Pasteur de Tunis, Université de Tunis El Manar, 13, Place Pasteur, BP 74, 1002, Tunis Belvédère, Tunisia
| | - Boutheina Ben Abdelmoumen Mardassi
- Institut Pasteur de Tunis Head of Mycoplasmas Unit Group of Mycoplasmas. Laboratory of Molecular Microbiology, Vaccinology, and Biotechnology Development 13, Place Pasteur, B.P. 74.1002 Tunis, Belvédère TUNISIA Tunis 1002 00216 71844790
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19
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Efficacy and mechanism of actions of natural antimicrobial drugs. Pharmacol Ther 2020; 216:107671. [PMID: 32916205 DOI: 10.1016/j.pharmthera.2020.107671] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/02/2020] [Accepted: 09/03/2020] [Indexed: 02/07/2023]
Abstract
Microbial infections have significantly increased over the last decades, and the mortality rates remain unacceptably high. The emergence of new resistance patterns and the spread of new viruses challenge the eradication of infectious diseases. The declining efficacy of antimicrobial drugs has become a global public health problem. Natural products derived from natural sources, such as plants, animals, and microorganisms, have significant efficacy for the treatment of infectious diseases accompanied by less adverse effects, synergy, and ability to overcome drug resistance. As the Chinese female scientist Youyou Tu received the Nobel Prize for the antimalarial drug artemisinin, antimicrobial drugs developed from Traditional Chinese Medicine are expected to receive increasing attention again. This review summarizes the antimicrobial agents derived from natural products approved for nearly 20 years and describes their efficacy and mode of action. The aim of this unit is to review the current status of antimicrobial drugs from natural products in order to increase the value of natural products as a source of novel drug candidates for infectious diseases.
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20
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Zuo X, Fang X, Zhang Z, Jin Z, Xi G, Liu Y, Tang Y. Antibacterial Activity and Pharmacokinetic Profile of a Promising Antibacterial Agent: 22-(2-Amino-phenylsulfanyl)-22-Deoxypleuromutilin. Molecules 2020; 25:E878. [PMID: 32079232 PMCID: PMC7071076 DOI: 10.3390/molecules25040878] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/14/2020] [Accepted: 02/14/2020] [Indexed: 02/07/2023] Open
Abstract
A new pleuromutilin derivative, 22-(2-amino-phenylsulfanyl)-22-deoxypleuromutilin (amphenmulin), has been synthesized and proved excellent in vitro and in vivo efficacy than that of tiamulin against methicillin-resistant Staphylococcus aureus (MRSA), suggesting this compound may lead to a promising antibacterial agent to treat MRSA infections. In this study, the effectiveness and safety of amphenmulin were further investigated. Amphenmulin showed excellent antibacterial activity against MRSA (minimal inhibitory concentration = 0.0156~8 µg/mL) and performed time-dependent growth inhibition and a concentration-dependent postantibiotic effect (PAE). Acute oral toxicity test in mice showed that amphenmulin was a practical non-toxic drug and possessed high security as a new drug with the 50% lethal dose (LD50) above 5000 mg/kg. The pharmacokinetic properties of amphenmulin were then measured. After intravenous administration, the elimination half-life (T1/2), total body clearance (Clβ), and area under curve to infinite time (AUC0→∞) were 1.92 ± 0.28 h, 0.82 ± 0.09 L/h/kg, and 12.23 ± 1.35 μg·h/mL, respectively. After intraperitoneal administration, the T1/2, Clβ/F and AUC0→∞ were 2.64 ± 0.72 h, 4.08 ± 1.14 L/h/kg, and 2.52 ± 0.81 μg·h/mL, respectively, while for the oral route were 2.91 ± 0.81 h, 6.31 ± 2.26 L/h/kg, 1.67 ± 0.66 μg·h/mL, respectively. Furthermore, we evaluated the antimicrobial activity of amphenmulin in an experimental model of MRSA wound infection. Amphenmulin enhanced wound closure and promoted the healing of wound, which inhibited MRSA bacterial counts in the wound and decreased serum levels of the pro-inflammatory cytokines TNF-α, IL-6, and MCP-1.
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Affiliation(s)
- Xiangyi Zuo
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (X.Z.); (X.F.); (Z.Z.); (Z.J.); (Y.L.)
| | - Xi Fang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (X.Z.); (X.F.); (Z.Z.); (Z.J.); (Y.L.)
| | - Zhaosheng Zhang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (X.Z.); (X.F.); (Z.Z.); (Z.J.); (Y.L.)
| | - Zhen Jin
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (X.Z.); (X.F.); (Z.Z.); (Z.J.); (Y.L.)
| | - Gaolei Xi
- Technology Center for China Tobacco Henan Industrial Limited Company, No. 8 The Third Street, Economic & Technology Development District, Zhengzhou 450000, China
| | - Yahong Liu
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (X.Z.); (X.F.); (Z.Z.); (Z.J.); (Y.L.)
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Youzhi Tang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (X.Z.); (X.F.); (Z.Z.); (Z.J.); (Y.L.)
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
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21
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Wicha WW, Prince WT, Lell C, Heilmayer W, Gelone SP. Pharmacokinetics and tolerability of lefamulin following intravenous and oral dosing. J Antimicrob Chemother 2019; 74:iii19-iii26. [PMID: 30949704 PMCID: PMC6449572 DOI: 10.1093/jac/dkz087] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVES To explore the pharmacokinetics (PK) of oral and intravenous (iv) lefamulin after single and multiple doses, and the effect of food on bioavailability. METHODS Lefamulin PK was examined in four studies. In Study 1, PK was assessed in patients with acute bacterial skin and skin structure infections who received repeated iv lefamulin q12h (150 mg). In Study 2, a four-period crossover study, healthy subjects received a single dose of oral lefamulin [immediate-release (IR) tablet, 1 × 600 mg] in a fasted and fed state, oral lefamulin (capsule, 3 × 200 mg) in a fasted state, and iv lefamulin in a fasted state. In Study 3, a three-period crossover study, healthy males received a single oral lefamulin dose (IR) in the following states: fasted, fasted followed by a high-calorie meal 1 h post-dose, and fed. Study 4 had two parts; in part A, healthy males received a single lefamulin dose (IR) in a fasted and fed state; in part B, subjects received repeated doses of lefamulin (IR, q12h) or placebo. Adverse events (AEs) were recorded in each study. RESULTS Single and repeated dosing of iv and oral lefamulin resulted in comparable exposure. Intravenous and oral lefamulin (given fasted or with a meal 1 h post-dose) resulted in bioequivalence. Bioequivalence was not established between oral lefamulin in the fed state and iv or oral administration in the fasted state. All AEs were mild or moderate in severity, no serious AEs were reported, and no participant discontinued because of an AE. CONCLUSIONS The PK of lefamulin supports successful switch from iv to oral therapy; lefamulin was generally well tolerated.
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22
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Retapamulin-Assisted Ribosome Profiling Reveals the Alternative Bacterial Proteome. Mol Cell 2019; 74:481-493.e6. [PMID: 30904393 DOI: 10.1016/j.molcel.2019.02.017] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/25/2019] [Accepted: 02/12/2019] [Indexed: 12/21/2022]
Abstract
The use of alternative translation initiation sites enables production of more than one protein from a single gene, thereby expanding the cellular proteome. Although several such examples have been serendipitously found in bacteria, genome-wide mapping of alternative translation start sites has been unattainable. We found that the antibiotic retapamulin specifically arrests initiating ribosomes at start codons of the genes. Retapamulin-enhanced Ribo-seq analysis (Ribo-RET) not only allowed mapping of conventional initiation sites at the beginning of the genes, but strikingly, it also revealed putative internal start sites in a number of Escherichia coli genes. Experiments demonstrated that the internal start codons can be recognized by the ribosomes and direct translation initiation in vitro and in vivo. Proteins, whose synthesis is initiated at internal in-frame and out-of-frame start sites, can be functionally important and contribute to the "alternative" bacterial proteome. The internal start sites may also play regulatory roles in gene expression.
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Lee GR, Maarouf M, Hendricks AK, Lee DE, Shi VY. Current and emerging therapies for hand eczema. Dermatol Ther 2019; 32:e12840. [DOI: 10.1111/dth.12840] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 01/12/2019] [Accepted: 01/24/2019] [Indexed: 12/26/2022]
Affiliation(s)
- Griffin R. Lee
- John A. Burns School of MedicineUniversity of Hawaii Honolulu Hawaii
| | | | - Aleksi K. Hendricks
- Division of Dermatology, Department of MedicineUniversity of Arizona Tucson Arizona
| | - Dylan E. Lee
- Department of MedicineJohn A. Burns School of Medicine, University of Hawaii Honolulu Hawaii
| | - Vivian Y. Shi
- Division of Dermatology, Department of MedicineUniversity of Arizona Tucson Arizona
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Abstract
Genetic coding in bacteria largely operates via the "one gene-one protein" paradigm. However, the peculiarities of the mRNA structure, the versatility of the genetic code, and the dynamic nature of translation sometimes allow organisms to deviate from the standard rules of protein encoding. Bacteria can use several unorthodox modes of translation to express more than one protein from a single mRNA cistron. One such alternative path is the use of additional translation initiation sites within the gene. Proteins whose translation is initiated at different start sites within the same reading frame will differ in their N termini but will have identical C-terminal segments. On the other hand, alternative initiation of translation in a register different from the frame dictated by the primary start codon will yield a protein whose sequence is entirely different from the one encoded in the main frame. The use of internal mRNA codons as translation start sites is controlled by the nucleotide sequence and the mRNA folding. The proteins of the alternative proteome generated via the "genes-within-genes" strategy may carry important functions. In this review, we summarize the currently known examples of bacterial genes encoding more than one protein due to the utilization of additional translation start sites and discuss the known or proposed functions of the alternative polypeptides in relation to the main protein product of the gene. We also discuss recent proteome- and genome-wide approaches that will allow the discovery of novel translation initiation sites in a systematic fashion.
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Abstract
Mycoplasmas are intrinsically resistant to antimicrobials targeting the cell wall (fosfomycin, glycopeptides, or β-lactam antibiotics) and to sulfonamides, first-generation quinolones, trimethoprim, polymixins, and rifampicin. The antibiotics most frequently used to control mycoplasmal infections in animals are macrolides and tetracyclines. Lincosamides, fluoroquinolones, pleuromutilins, phenicols, and aminoglycosides can also be active. Standardization of methods used for determination of susceptibility levels is difficult since no quality control strains are available and because of species-specific growth requirements. Reduced susceptibility levels or resistances to several families of antimicrobials have been reported in field isolates of pathogenic Mycoplasma species of major veterinary interest: M. gallisepticum and M. synoviae in poultry; M. hyopneumoniae, M. hyorhinis, and M. hyosynoviae in swine; M. bovis in cattle; and M. agalactiae in small ruminants. The highest resistances are observed for macrolides, followed by tetracyclines. Most strains remain susceptible to fluoroquinolones. Pleuromutilins are the most effective antibiotics in vitro. Resistance frequencies vary according to the Mycoplasma species but also according to the countries or groups of animals from which the samples were taken. Point mutations in the target genes of different antimicrobials have been identified in resistant field isolates, in vitro-selected mutants, or strains reisolated after an experimental infection followed by one or several treatments: DNA-gyrase and topoisomerase IV for fluoroquinolones; 23S rRNA for macrolides, lincosamides, pleuromutilins, and amphenicols; 16S rRNAs for tetracyclines and aminoglycosides. Further work should be carried out to determine and harmonize specific breakpoints for animal mycoplasmas so that in vitro information can be used to provide advice on selection of in vivo treatments.
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Abstract
Each month, subscribers to The Formulary Monograph Service receive five to six well-documented monographs on drugs that are newly released or are in late phase 3 trials. The monographs are targeted to your Pharmacy and Therapeutics Committee. Subscribers also receive monthly one-page summary monographs on the agents that are useful for agendas and pharmacy/nursing in-services. A comprehensive target drug utilization evaluation (DUE) is also provided each month. With a subscription, the monographs are sent to you in print and CD-ROM forms and are available online. Monographs can be customized to meet the needs of your facility. Subscribers to the The Formulary Monograph Service also receive access to a pharmacy bulletin board, The Formulary Information Exchange ( The F.I.X.). All topics pertinent to clinical and hospital pharmacy are discussed on The F.I.X. Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. If you would like information about The Formulary Monograph Service or The F.I.X., call The Formulary at 800-322-4349. The September 2007 monograph topics are rivastigmine transdermal system, ixabepilone, desvenlafaxine succinate extended-release, tedisamil, and sumatriptan succinate and naproxen sodium. The DUE is on formoterol fumarate inhalation solution.
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Affiliation(s)
| | - Terri Levien
- Drug Information Center, Washington State University Spokane, Wash
| | - Danial E. Baker
- Drug Information Center and College of Pharmacy, Washington State University Spokane, PO Box 1495, Spokane, WA 99210-1495
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Gao ML, Zeng J, Fang X, Luo J, Jin Z, Liu YH, Tang YZ. Design, synthesis and antibacterial evaluation of novel pleuromutilin derivatives possessing piperazine linker. Eur J Med Chem 2017; 127:286-295. [PMID: 28068600 DOI: 10.1016/j.ejmech.2017.01.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 12/11/2016] [Accepted: 01/01/2017] [Indexed: 01/23/2023]
Abstract
A series of pleuromutilin derivatives bearing piperazine ring have been reported. The in vitro antibacterial activities of the synthetic derivatives against MRSA (ATCC 43300), Staphylococcus aureus (ATCC 29213), Enterococcus faecalis (ATCC 29212), Enterococcus faecium (ATCC35667) and Escherichia coli (ATCC25922) were evaluated by the broth dilution method. Most of the synthesized derivatives displayed potent activities. Compounds 11c, 12a and 12c were found to be the most active antibacterial derivatives against MRSA (minimum inhibitory concentration = 0.015 μg/mL). The binding of compounds 11c, 12a and 12c to the 50s ribosome were investigated by molecular modeling. Compound 11c possessed lower binding free energy compared with compounds 12a and 12c. Compound 11c was further evaluated in MRSA systemic infection model and displayed superior in vivo efficacy to that of tiamulin.
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Affiliation(s)
- Mei-Ling Gao
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Jie Zeng
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Xi Fang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Jian Luo
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Zhen Jin
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Ya-Hong Liu
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - You-Zhi Tang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.
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Paukner S, Riedl R. Pleuromutilins: Potent Drugs for Resistant Bugs-Mode of Action and Resistance. Cold Spring Harb Perspect Med 2017; 7:a027110. [PMID: 27742734 PMCID: PMC5204327 DOI: 10.1101/cshperspect.a027110] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Pleuromutilins are antibiotics that selectively inhibit bacterial translation and are semisynthetic derivatives of the naturally occurring tricyclic diterpenoid pleuromutilin, which received its name from the pleuromutilin-producing fungus Pleurotus mutilus Tiamulin and valnemulin are two established derivatives in veterinary medicine for oral and intramuscular administration. As these early pleuromutilin drugs were developed at a time when companies focused on major antibacterial classes, such as the β-lactams, and resistance was not regarded as an issue, interest in antibiotic research including pleuromutilins was limited. Over the last decade or so, there has been a resurgence in interest to develop this class for human use. This has resulted in a topical derivative, retapamulin, and additional derivatives in clinical development. The most advanced compound is lefamulin, which is in late-stage development for the intravenous and oral treatment of community-acquired bacterial pneumonia and acute bacterial skin infections. Overall, pleuromutilins and, in particular, lefamulin are characterized by potent activity against Gram-positive and fastidious Gram-negative pathogens as well as against mycoplasmas and intracellular organisms, such as Chlamydia spp. and Legionella pneumophila Pleuromutilins are unaffected by resistance to other major antibiotic classes, such as macrolides, fluoroquinolones, tetracyclines, β-lactam antibiotics, and others. Furthermore, pleuromutilins display very low spontaneous mutation frequencies and slow, stepwise resistance development at sub-MIC in vitro. The potential for resistance development in clinic is predicted to be slow as confirmed by extremely low resistance rates to this class despite the use of pleuromutilins in veterinary medicine for >30 years. Although rare, resistant strains have been identified in human- and livestock-associated environments and as with any antibiotic class, require close monitoring as well as prudent use in veterinary medicine. This review focuses on the structural characteristics, mode of action, antibacterial activity, and resistance development of this potent and novel antibacterial class for systemic use in humans.
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Creech CB, Al-Zubeidi DN, Fritz SA. Prevention of Recurrent Staphylococcal Skin Infections. Infect Dis Clin North Am 2016; 29:429-64. [PMID: 26311356 DOI: 10.1016/j.idc.2015.05.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Staphylococcus aureus infections pose a significant health burden. The emergence of community-associated methicillin-resistant S aureus has resulted in an epidemic of skin and soft tissue infections (SSTI), and many patients experience recurrent SSTI. As S aureus colonization is associated with subsequent infection, decolonization is recommended for patients with recurrent SSTI or in settings of ongoing transmission. S aureus infections often cluster within households, and asymptomatic carriers serve as reservoirs for transmission; therefore, a household approach to decolonization is more effective than measures performed by individuals alone. Novel strategies for the prevention of recurrent SSTI are needed.
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Affiliation(s)
- C Buddy Creech
- Vanderbilt Vaccine Research Program, Division of Pediatric Infectious Diseases, Department of Pediatrics, Vanderbilt University School of Medicine and the Monroe Carell, Jr. Children's Hospital at Vanderbilt, S2323 MCN, 1161 21st Avenue South, Nashville, TN 37232, USA
| | - Duha N Al-Zubeidi
- Department of Pediatrics, Children's Mercy Hospital Infection Prevention and Control, University of Missouri-Kansas City School of Medicine, 2401 Gillham Road, Kansas City, MO 64108, USA
| | - Stephanie A Fritz
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8116, St Louis, MO 63110, USA.
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Bailey AM, Alberti F, Kilaru S, Collins CM, de Mattos-Shipley K, Hartley AJ, Hayes P, Griffin A, Lazarus CM, Cox RJ, Willis CL, O’Dwyer K, Spence DW, Foster GD. Identification and manipulation of the pleuromutilin gene cluster from Clitopilus passeckerianus for increased rapid antibiotic production. Sci Rep 2016; 6:25202. [PMID: 27143514 PMCID: PMC4855138 DOI: 10.1038/srep25202] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 04/11/2016] [Indexed: 12/16/2022] Open
Abstract
Semi-synthetic derivatives of the tricyclic diterpene antibiotic pleuromutilin from the basidiomycete Clitopilus passeckerianus are important in combatting bacterial infections in human and veterinary medicine. These compounds belong to the only new class of antibiotics for human applications, with novel mode of action and lack of cross-resistance, representing a class with great potential. Basidiomycete fungi, being dikaryotic, are not generally amenable to strain improvement. We report identification of the seven-gene pleuromutilin gene cluster and verify that using various targeted approaches aimed at increasing antibiotic production in C. passeckerianus, no improvement in yield was achieved. The seven-gene pleuromutilin cluster was reconstructed within Aspergillus oryzae giving production of pleuromutilin in an ascomycete, with a significant increase (2106%) in production. This is the first gene cluster from a basidiomycete to be successfully expressed in an ascomycete, and paves the way for the exploitation of a metabolically rich but traditionally overlooked group of fungi.
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Affiliation(s)
- Andy M. Bailey
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Fabrizio Alberti
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Sreedhar Kilaru
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Catherine M. Collins
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Kate de Mattos-Shipley
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Amanda J. Hartley
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Patrick Hayes
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Alison Griffin
- GSK, Southdownview Way, Worthing, West Sussex, BN14 8QH, UK
| | - Colin M. Lazarus
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Russell J. Cox
- School of Chemistry, University of Bristol, Cantock’s Close Bristol, BS8 1TS, UK
| | - Christine L. Willis
- School of Chemistry, University of Bristol, Cantock’s Close Bristol, BS8 1TS, UK
| | - Karen O’Dwyer
- GSK, 1250 S. Collegeville Road, Collegeville, Pennsylvania, 19426-0989, United States
| | - David W. Spence
- School of Chemistry, University of Bristol, Cantock’s Close Bristol, BS8 1TS, UK
| | - Gary D. Foster
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
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Xiao H, Zhong JJ. Production of Useful Terpenoids by Higher-Fungus Cell Factory and Synthetic Biology Approaches. Trends Biotechnol 2016; 34:242-255. [DOI: 10.1016/j.tibtech.2015.12.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/01/2015] [Accepted: 12/15/2015] [Indexed: 01/11/2023]
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Abstract
Without a doubt, our current antimicrobials are losing the battle in the fight against newly-emerged multidrug-resistant pathogens. There is a pressing, unmet need for novel antimicrobials and novel approaches to develop them; however, it is becoming increasingly difficult and costly to develop new antimicrobials. One strategy to reduce the time and cost associated with antimicrobial innovation is drug repurposing, which is to find new applications outside the scope of the original medical indication of the drug. Ebselen, an organoselenium clinical molecule, possesses potent antimicrobial activity against clinical multidrug-resistant Gram-positive pathogens, including Staphylococcus, Streptococcus, and Enterococcus, but not against Gram-negative pathogens. Moreover, the activity of ebselen against Gram-positive pathogens exceeded those activities determined for vancomycin and linezolid, drugs of choice for treatment of Enterococcus and Staphylococcus infections. The minimum inhibitory concentrations of ebselen at which 90% of clinical isolates of Enterococcus and Staphylococcus were inhibited (MIC90) were found to be 0.5 and 0.25 mg/L, respectively. Ebselen showed significant clearance of intracellular methicillin-resistant S. aureus (MRSA) in comparison to vancomycin and linezolid. We demonstrated that ebselen inhibits the bacterial translation process without affecting mitochondrial biogenesis. Additionally, ebselen was found to exhibit excellent activity in vivo in a Caenorhabditis elegans MRSA-infected whole animal model. Finally, ebselen showed synergistic activities with conventional antimicrobials against MRSA. Taken together, our results demonstrate that ebselen, with its potent antimicrobial activity and safety profiles, can be potentially used to treat multidrug resistant Gram-positive bacterial infections alone or in combination with other antibiotics and should be further clinically evaluated.
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Affiliation(s)
- Shankar Thangamani
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, West Lafayette, IN, United States of America
| | - Waleed Younis
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, West Lafayette, IN, United States of America
| | - Mohamed N. Seleem
- Department of Comparative Pathobiology, Purdue University College of Veterinary Medicine, West Lafayette, IN, United States of America
- * E-mail:
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Bohaty BR, Choi S, Cai C, Hebert AA. Clinical and bacteriological efficacy of twice daily topical retapamulin ointment 1% in the management of impetigo and other uncomplicated superficial skin infections. Int J Womens Dermatol 2015; 1:13-20. [PMID: 28491950 PMCID: PMC5418665 DOI: 10.1016/j.ijwd.2014.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 12/12/2014] [Accepted: 12/13/2014] [Indexed: 10/27/2022] Open
Abstract
BACKGROUND Cutaneous bacterial infections are common in children and adults and frequently are caused by Staphylococcus aureus (S. aureus). Treatment failures with topical agents are not uncommon and have been shown to be secondary to bacterial resistance. OBJECTIVE To determine clinical and bacteriological efficacy of retapamulin ointment 1% in treatment of patients with cutaneous bacterial infections caused by methicillin-resistant S. aureus (MRSA) and other bacteria. METHODS Prospective, nonrandomized, uncontrolled, open label, single center trial conducted between April 2008 and November 2012 that evaluated efficacy of retapamulin ointment 1% in the treatment of impetigo, folliculitis, and other minor soft tissue infections in children and adults. Fifty patients, who presented to a dermatology outpatient clinic and were clinically diagnosed with impetigo, folliculitis, or minor soft tissue infection suitable for treatment with a topical antibiotic, were screened. Thirty-eight patients were enrolled and received treatment: topical retapamulin ointment 1% twice daily for 5 days. Seven patients were MRSA positive and qualified for the primary efficacy population. One patient withdrew due to an adverse event. Clinical and microbiological exams were performed at baseline and follow-up 5 to 7 days later to assess clinical, microbiological, and therapeutic responses. Primary outcome was clinical response at follow-up in primary efficacy population with MRSA isolated as the baseline pathogen. Secondary outcomes included clinical, microbiologic, and therapeutic responses in patients who were culture positive for any species of bacteria. RESULTS Clinical response at follow-up in the primary efficacy population (MRSA-positive patients) was not sufficiently powered to demonstrate significance; however, outcomes were excellent, with 7 of 7 patients demonstrating clinical success (5 of 7) or clinical improvement (2 of 7) at follow-up. Barring lack of significance due to small total sample size for patients who were culture positive for any species of bacteria (n = 35), overall success rates were favorable for clinical, microbiologic, and therapeutic responses with values of 66%, 97%, and 69%, respectively. Adverse events (AEs) were mild or moderate in severity. No serious AEs were reported. CONCLUSION Safety profile appears favorable given the low number of AEs. Study design limits conclusions that can be drawn. Nevertheless, this study supports use of topical retapamulin 1% ointment in treatment of cutaneous bacterial infections, particularly those caused by S. aureus, including MRSA.
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Affiliation(s)
- Benjamin R. Bohaty
- Department of Dermatology, The University of Texas Health Science Center at Houston, Houston, TX
| | - Sangbum Choi
- Division of Clinical and Translational Sciences, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX
| | - Chunyan Cai
- Division of Clinical and Translational Sciences, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX
| | - Adelaide A. Hebert
- Departments of Dermatology and Pediatrics, The University of Texas Health Science Center at Houston, Houston, TX
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Stockdale TP, Williams CM. Pharmaceuticals that contain polycyclic hydrocarbon scaffolds. Chem Soc Rev 2015; 44:7737-63. [DOI: 10.1039/c4cs00477a] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review comprehensively explores approved pharmaceutical compounds that contain polycyclic scaffolds and the properties that these skeletons convey.
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Affiliation(s)
- Tegan P. Stockdale
- School of Chemistry and Molecular Biosciences
- University of Queensland
- St Lucia
- Australia
| | - Craig M. Williams
- School of Chemistry and Molecular Biosciences
- University of Queensland
- St Lucia
- Australia
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Ling C, Fu L, Gao S, Chu W, Wang H, Huang Y, Chen X, Yang Y. Design, synthesis, and structure-activity relationship studies of novel thioether pleuromutilin derivatives as potent antibacterial agents. J Med Chem 2014; 57:4772-95. [PMID: 24874438 DOI: 10.1021/jm500312x] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A series of novel thioether pleuromutilin derivatives incorporating various heteroaromatic substituents into the C14 side chain have been reported. Structure-activity relationship (SAR) studies resulted in compounds 52 and 55 with the most potent in vitro antibacterial activity among the series (MIC = 0.031-0.063 μg/mL). Further optimization to overcome the poor water solubility of compound 55 resulted in compounds 87, 91, 109, and 110 possessing good in vitro antibacterial activity with increased hydrophilicity. Compound 114, the water-soluble phosphate prodrug of compound 52, was also prepared and evaluated. Among the derivatives, compound 110 showed moderate pharmacokinetic profiles and good in vivo efficacy in both MSSA and MRSA systemic infection models. Compound 110 was further evaluated in CYP450 inhibition assay and displayed intermediate in vitro inhibition of CYP3A4.
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Affiliation(s)
- Chenyu Ling
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203, China
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Jacobs MR. Retapamulin: focus on its use in the treatment of uncomplicated superficial skin infections and impetigo. ACTA ACUST UNITED AC 2014. [DOI: 10.1586/edm.10.45] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Copeland RA. The dynamics of drug-target interactions: drug-target residence time and its impact on efficacy and safety. Expert Opin Drug Discov 2012; 5:305-10. [PMID: 22823083 DOI: 10.1517/17460441003677725] [Citation(s) in RCA: 148] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The extent and duration of pharmacological action is determined by the lifetime of drug occupancy on a molecular target. This lifetime is defined by dynamic processes that control the rates of drug association and dissociation from the target. Recently, the term residence time has been coined to describe experimental measurements that can be related to the lifetime of the binary drug-target complex, and this in turn to durable, pharmacodynamic activity. The residence time concept and its impact on drug optimization are reviewed here. Examples are provided that demonstrate how a long residence time can improve drug efficacy in vivo. Additionally, optimization of drug-target residence time can help to mitigate off-target mediated toxicity, hence, improving drug safety and tolerability. Recent applications of the residence time concept to both drug discovery and development are also presented.
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Affiliation(s)
- Robert A Copeland
- Epizyme, Inc., 840 Memorial Drive, Cambridge, MA 02139, USA 617-401-8261 ; 617-349-0707 ;
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Abstract
Impetigo is a common cutaneous infection that is especially prevalent in children. The prevalence of colonization and infection with resistant strains is continually increasing, forcing clinicians to reevaluate treatment strategies. Newer topical agents are effective in treating infections with resistant strains and may help minimize resistance and adverse effects from systemic agents. Use of topical disinfectants to decrease colonization is an important adjunctive measure. Physicians should be aware of local resistance patterns in impetigo to help guide therapy.
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Affiliation(s)
- Scott Bangert
- Dermatology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
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Abstract
In 1951, the first reference to the antibacterial substance pleuromutilin was made in a paper published in the Proceedings of the National Academy of Sciences. Researchers had identified several species of the mold genus Pleurotus that inhibited the growth of Staphylococcus aureus. The elucidation of the structure in 1962 led to the initiation of a development program at Sandoz, which was followed by the approval of tiamulin in 1979 for use in veterinary medicine. Although in 2007 retapamulin became the first pleuromutilin approved for topical use in humans, it was not until 2011, exactly 60 years after the first mention of the class, that a pleuromutilin antibiotic, BC-3781, could be tested successfully in a clinical phase II trial for systemic use in patients. This review will discuss key aspects of this antibacterial class and provide some insight into the question of why it took half a century to develop a systemic pleuromutilin for human use.
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Copeland RA, Basavapathruni A, Moyer M, Scott MP. Impact of enzyme concentration and residence time on apparent activity recovery in jump dilution analysis. Anal Biochem 2011; 416:206-10. [DOI: 10.1016/j.ab.2011.05.029] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 05/10/2011] [Accepted: 05/19/2011] [Indexed: 01/26/2023]
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Liu J, Lotesta SD, Sorensen EJ. A concise synthesis of the molecular framework of pleuromutilin. Chem Commun (Camb) 2011; 47:1500-2. [PMID: 21079876 PMCID: PMC3156455 DOI: 10.1039/c0cc04077k] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Two syntheses of the tricyclic carbon skeleton of pleuromutilin are reported. Diastereoselective 1,4-conjugate additions were used to elaborate bicyclic precursors at an early stage of each route, while ring-forming olefin metatheses were executed to complete the pleuromutilin carbon framework. The congeners prepared are appropriately functionalized to enable access to diverse pleuromutilin analogues.
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Affiliation(s)
- Junjia Liu
- Department of Chemistry, Princeton University, Princeton, NJ 08540, USA; Fax: +1-608-258-1980; Tel: +1-609-258-8135, Frick Chemical Laboratory
| | - Stephen D. Lotesta
- Department of Chemistry, Princeton University, Princeton, NJ 08540, USA; Fax: +1-608-258-1980; Tel: +1-609-258-8135, Frick Chemical Laboratory
| | - Erik J. Sorensen
- Department of Chemistry, Princeton University, Princeton, NJ 08540, USA; Fax: +1-608-258-1980; Tel: +1-609-258-8135, Frick Chemical Laboratory
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Scimeca CL, Bharara M, Fisher TK, Kimbriel H, Mills JL, Armstrong DG. An update on pharmacological interventions for diabetic foot ulcers. Foot Ankle Spec 2010; 3:285-302. [PMID: 20685955 DOI: 10.1177/1938640010376994] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Diabetic foot ulcers are the most common lower extremity complications of diabetes. Peripheral neuropathy and peripheral vascular disease are the underlying risk factors for diabetic foot ulcers, subsequently leading to infections and requiring antimicrobial therapy for the management of the disease. Each risk factor is a target for clinical intervention, with the intent to delay or prevent disease progression to amputation. The effective therapy includes interdisciplinary care, which involves optimized pharmacological interventions in concert with other treatments such as debridement strategies and specialized wound dressings. The pharmacological therapy alone cannot lead to successful therapy, and therefore, these supplementary techniques/modalities should not be overlooked. It is therefore the aim of this report to review various pharmacological interventions, specific to the diabetic foot and wound healing, along with incorporation of advanced therapies required to achieve a multifaceted treatment of diabetic foot ulcers and provide basis for superior drugs as well as drug delivery systems.
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Affiliation(s)
- Christy L Scimeca
- Southern Arizona Limb Salvage Alliance, Department of Surgery, University of Arizona College of Medicine, Tucson, Arizona, USA
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44
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Paradigm shift in discovering next-generation anti-infective agents: targeting quorum sensing, c-di-GMP signaling and biofilm formation in bacteria with small molecules. Future Med Chem 2010; 2:1005-35. [DOI: 10.4155/fmc.10.185] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Small molecules that can attenuate bacterial toxin production or biofilm formation have the potential to solve the bacteria resistance problem. Although several molecules, which inhibit bacterial cell-to-cell communication (quorum sensing), biofilm formation and toxin production, have been discovered, there is a paucity of US FDA-approved drugs that target these processes. Here, we review the current understanding of quorum sensing in important pathogens such as Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus and provide examples of experimental molecules that can inhibit both known and unknown targets in bacterial virulence factor production and biofilm formation. Structural data for protein targets that are involved in both quorum sensing and cyclic diguanylic acid signaling are needed to aid the development of molecules with drug-like properties in order to target bacterial virulence factors production and biofilm formation.
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45
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Li BB, Shen JZ, Cao XY, Wang Y, Dai L, Huang SY, Wu CM. Mutations in 23S rRNA gene associated with decreased susceptibility to tiamulin and valnemulin in Mycoplasma gallisepticum. FEMS Microbiol Lett 2010; 308:144-9. [DOI: 10.1111/j.1574-6968.2010.02003.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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46
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Abstract
Bacterial ribosomal RNA is the target of clinically important antibiotics, while biologically important RNAs in viral and eukaryotic genomes present a range of potential drug targets. The physicochemical properties of RNA present difficulties for medicinal chemistry, particularly when oral availability is needed. Peptidic ligands and analysis of their RNA-binding properties are providing insight into RNA recognition. RNA-binding ligands include far more chemical classes than just aminoglycosides. Chemical functionalities from known RNA-binding small molecules are being exploited in fragment- and ligand-based projects. While targeting of RNA for drug design is very challenging, continuing advances in our understanding of the principles of RNA–ligand interaction will be necessary to realize the full potential of this class of targets.
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47
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Van Bambeke F, Glupczynski Y, Mingeot-Leclercq MP, Tulkens PM. Mechanisms of action. Infect Dis (Lond) 2010. [DOI: 10.1016/b978-0-323-04579-7.00130-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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48
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Locke JB, Hilgers M, Shaw KJ. Novel ribosomal mutations in Staphylococcus aureus strains identified through selection with the oxazolidinones linezolid and torezolid (TR-700). Antimicrob Agents Chemother 2009; 53:5265-74. [PMID: 19752277 PMCID: PMC2786364 DOI: 10.1128/aac.00871-09] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 07/31/2009] [Accepted: 09/03/2009] [Indexed: 11/20/2022] Open
Abstract
TR-700 (torezolid), the active moiety of the novel oxazolidinone phosphate prodrug TR-701, is highly potent against gram-positive pathogens, including strains resistant to linezolid (LZD). Here we investigated the potential of Staphylococcus aureus strains ATCC 29213 (methicillin-susceptible S. aureus [MSSA]) and ATCC 33591 (methicillin-resistant S. aureus [MRSA]) to develop resistance to TR-700. The spontaneous frequencies of mutation of MSSA 29213 and MRSA 33591 resulting in reduced susceptibility to TR-700 at 2 x the MIC were 1.1 x 10(-10) and 1.9 x 10(-10), respectively. These values are approximately 16-fold lower than the corresponding LZD spontaneous mutation frequencies of both strains. Following 30 serial passages in the presence of TR-700, the MIC for MSSA 29213 remained constant (0.5 microg/ml) while increasing eightfold (0.25 to 2.0 microg/ml) for MRSA 33591. Serial passage of MSSA 29213 and MRSA 33591 in LZD resulted in 64- and 32-fold increases in LZD resistance (2 to 128 microg/ml and 1 to 32 microg/ml, respectively). Domain V 23S rRNA gene mutations (Escherichia coli numbering) found in TR-700-selected mutants included T2500A and a novel coupled T2571C/G2576T mutation, while LZD-selected mutants included G2447T, T2500A, and G2576T. We also identified mutations correlating with decreased susceptibility to TR-700 and LZD in the rplC and rplD genes, encoding the 50S ribosomal proteins L3 and L4, respectively. L3 mutations included Gly152Asp, Gly155Arg, Gly155Arg/Met169Leu, and DeltaPhe127-His146. The only L4 mutation detected was Lys68Gln. TR-700 maintained a fourfold or greater potency advantage over LZD against all strains with ribosomal mutations. These data bring to light a variety of novel and less-characterized mutations associated with S. aureus resistance to oxazolidinones and demonstrate the low resistance potential of torezolid.
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Affiliation(s)
- Jeffrey B. Locke
- Trius Therapeutics, Inc., 6310 Nancy Ridge Drive, Suite 105, San Diego, California 92121
| | - Mark Hilgers
- Trius Therapeutics, Inc., 6310 Nancy Ridge Drive, Suite 105, San Diego, California 92121
| | - Karen Joy Shaw
- Trius Therapeutics, Inc., 6310 Nancy Ridge Drive, Suite 105, San Diego, California 92121
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49
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Scangarella-Oman NE, Shawar RM, Bouchillon S, Hoban D. Microbiological profile of a new topical antibacterial: retapamulin ointment 1%. Expert Rev Anti Infect Ther 2009; 7:269-79. [PMID: 19344241 DOI: 10.1586/eri.09.7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Retapamulin is a new topical pleuromutilin antibiotic for the treatment of skin and skin-structure infections, including impetigo. In vitro studies indicate that retapamulin has a unique mode of action that minimizes the potential for target-specific cross-resistance with other antibacterials and a limited potential for resistance development. Its spectrum of activity includes the most likely causative pathogens Staphylococcus aureus and Streptococcus pyogenes. In the Global Surveillance Program, retapamulin was highly active in vitro, including against strains of S. aureus resistant to methicillin, mupirocin or fusidic acid. In clinical studies, retapamulin was noninferior to fusidic acid and oral cefalexin, achieving per-pathogen success rates of 86-99%. Topical retapamulin has a good safety profile and is associated with high patient compliance.
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50
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Long KS, Poehlsgaard J, Hansen LH, Hobbie SN, Böttger EC, Vester B. Single 23S rRNA mutations at the ribosomal peptidyl transferase centre confer resistance to valnemulin and other antibiotics in Mycobacterium smegmatis by perturbation of the drug binding pocket. Mol Microbiol 2009; 71:1218-27. [PMID: 19154331 DOI: 10.1111/j.1365-2958.2009.06596.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tiamulin and valnemulin target the peptidyl transferase centre (PTC) on the bacterial ribosome. They are used in veterinary medicine to treat infections caused by a variety of bacterial pathogens, including the intestinal spirochetes Brachyspira spp. Mutations in ribosomal protein L3 and 23S rRNA have previously been associated with tiamulin resistance in Brachyspira spp. isolates, but as multiple mutations were isolated together, the roles of the individual mutations are unclear. In this work, individual 23S rRNA mutations associated with pleuromutilin resistance at positions 2055, 2447, 2504 and 2572 (Escherichia coli numbering) are introduced into a Mycobacterium smegmatis strain with a single rRNA operon. The single mutations each confer a significant and similar degree of valnemulin resistance and those at 2447 and 2504 also confer cross-resistance to other antibiotics that bind to the PTC in M. smegmatis. Antibiotic footprinting experiments on mutant ribosomes show that the introduced mutations cause structural perturbations at the PTC and reduced binding of pleuromutilin antibiotics. This work underscores the fact that mutations at nucleotides distant from the pleuromutilin binding site can confer the same level of valnemulin resistance as those at nucleotides abutting the bound drug, and suggests that the former function indirectly by altering local structure and flexibility at the drug binding pocket.
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Affiliation(s)
- Katherine S Long
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark.
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