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Chunduru J, LaRoe N, Garza J, Hamood AN, Paré PW. Nosocomial Bacteria Inhibition with Polymyxin B: In Silico Gene Mining and In Vitro Analysis. Antibiotics (Basel) 2024; 13:745. [PMID: 39200045 PMCID: PMC11350920 DOI: 10.3390/antibiotics13080745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2024] [Revised: 08/03/2024] [Accepted: 08/06/2024] [Indexed: 09/01/2024] Open
Abstract
Multidrug-resistant bacteria present a significant public health challenge; such pathogens exhibit reduced susceptibility to conventional antibiotics, limiting current treatment options. Cationic non-ribosomal peptides (CNRPs) such as brevicidine and polymyxins have emerged as promising candidates to block Gram-negative bacteria. To investigate the capability of bacteria to biosynthesize CNRPs, and specifically polymyxins, over 11,000 bacterial genomes were mined in silico. Paenibacillus polymyxa was identified as having a robust biosynthetic capacity, based on multiple polymyxin gene clusters. P. polymyxa biosynthetic competence was confirmed by metabolite characterization via HPLC purification and MALDI TOF/TOF analysis. When grown in a selected medium, the metabolite yield was 4 mg/L with a 20-fold specific activity increase. Polymyxin B (PMB) was assayed with select nosocomial pathogens, including Pseudomonas aeruginosa, Klebsiella pneumonia, and Acinetobacter baumaii, which exhibited minimum inhibitory concentrations of 4, 1, and 1 µg/mL, respectively.
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Affiliation(s)
- Jayendra Chunduru
- Chemistry & Biochemistry Department, Texas Tech University, Lubbock, TX 79409, USA
| | - Nicholas LaRoe
- Chemistry & Biochemistry Department, Texas Tech University, Lubbock, TX 79409, USA
| | - Jeremy Garza
- Department of Immunology & Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA (A.N.H.)
| | - Abdul N. Hamood
- Department of Immunology & Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA (A.N.H.)
| | - Paul W. Paré
- Chemistry & Biochemistry Department, Texas Tech University, Lubbock, TX 79409, USA
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Yang S, Wang H, Zhao D, Zhang S, Hu C. Polymyxins: recent advances and challenges. Front Pharmacol 2024; 15:1424765. [PMID: 38974043 PMCID: PMC11224486 DOI: 10.3389/fphar.2024.1424765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2024] [Accepted: 06/04/2024] [Indexed: 07/09/2024] Open
Abstract
Antibiotic resistance is a pressing global health challenge, and polymyxins have emerged as the last line of defense against multidrug-resistant Gram-negative (MDR-GRN) bacterial infections. Despite the longstanding utility of colistin, the complexities surrounding polymyxins in terms of resistance mechanisms and pharmacological properties warrant critical attention. This review consolidates current literature, focusing on polymyxins antibacterial mechanisms, resistance pathways, and innovative strategies to mitigate resistance. We are also investigating the pharmacokinetics of polymyxins to elucidate factors that influence their in vivo behavior. A comprehensive understanding of these aspects is pivotal for developing next-generation antimicrobials and optimizing therapeutic regimens. We underscore the urgent need for advancing research on polymyxins to ensure their continued efficacy against formidable bacterial challenges.
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Affiliation(s)
- Shan Yang
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Hairui Wang
- Institute of Respiratory Health, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Dan Zhao
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Shurong Zhang
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Chenggong Hu
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China
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Armstrong DW, Berthod A. Occurrence of D-amino acids in natural products. NATURAL PRODUCTS AND BIOPROSPECTING 2023; 13:47. [PMID: 37932633 PMCID: PMC10628113 DOI: 10.1007/s13659-023-00412-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/19/2023] [Indexed: 11/08/2023]
Abstract
Since the identified standard genetic code contains 61 triplet codons of three bases for the 20 L-proteinogenic amino acids (AAs), no D-AA should be found in natural products. This is not what is observed in the living world. D-AAs are found in numerous natural compounds produced by bacteria, algae, fungi, or marine animals, and even vertebrates. A review of the literature indicated the existence of at least 132 peptide natural compounds in which D-AAs are an essential part of their structure. All compounds are listed, numbered and described herein. The two biosynthetic routes leading to the presence of D-AA in natural products are: non-ribosomal peptide synthesis (NRPS), and ribosomally synthesized and post-translationally modified peptide (RiPP) synthesis which are described. The methods used to identify the AA chirality within naturally occurring peptides are briefly discussed. The biological activity of an all-L synthetic peptide is most often completely different from that of the D-containing natural compounds. Analyzing the selected natural compounds showed that D-Ala, D-Val, D-Leu and D-Ser are the most commonly encountered D-AAs closely followed by the non-proteinogenic D-allo-Thr. D-Lys and D-Met were the least prevalent D-AAs in naturally occurring compounds.
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Affiliation(s)
- Daniel W Armstrong
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, TX, 76019, USA.
| | - Alain Berthod
- Institut des Sciences Analytiques, CNRS, University of Lyon 1, 69100, Villeurbanne, France
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Wang H, Wang N, Tan Y, Mi Q, Mao Y, Zhao C, Tian X, Liu W, Huang L. Paenibacillus polymyxa YLC1: a promising antagonistic strain for biocontrol of Pseudomonas syringae pv. actinidiae, causing kiwifruit bacterial canker. PEST MANAGEMENT SCIENCE 2023; 79:4357-4366. [PMID: 37417001 DOI: 10.1002/ps.7633] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/23/2023] [Accepted: 07/07/2023] [Indexed: 07/08/2023]
Abstract
BACKGROUND Kiwifruit bacterial canker (KBC) caused by Pseudomonas syringae pv. actinidiae (Psa) is the main limiting factor in the kiwifruit industry. This study aimed to identify bacterial strains with antagonistic activity against Psa, analyze antagonistically active substances and provide a new basis for the biological control of KBC. RESULTS A total of 142 microorganisms were isolated from the rhizosphere soil of asymptomatic kiwifruit. Among them, an antagonistic bacterial strain was identified as Paenibacillus polymyxa YLC1 by 16S rRNA sequencing. KBC control by strain YLC1 (85.4%) was comparable to copper hydroxide treatment (81.8%) under laboratory conditions and field testing. Active substances of strain YLC1 were identified by genetic sequence analysis using antiSMASH. Six biosynthetic active compound gene clusters were identified as encoding ester peptide synthesis, such as polymyxins. An active fraction was purified and identified as polymyxin B1 using chromatography, hydrogen nuclear magnetic resonance (NMR), and liquid chromatography-mass spectrometry. In addition, polymyxin B1 also was found significantly to suppress the expression of T3SS-related genes, but did not affect the growth of Psa at low concentrations. CONCLUSION In this study, a biocontrol strain P. polymyxa YLC1 obtained from kiwifruit rhizosphere soil exhibited excellent control effects on KBC in vitro and in field tests. Its active compound was identified as polymyxin B1, which inhibits a variety of pathogenic bacteria. We conclude that P. polymyxa YLC1 is a biocontrol strain with excellent prospects for development and application. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Hua Wang
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China
| | - Nana Wang
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Life Science, Northwest A&F University, Yangling, People's Republic of China
| | - Yunxiao Tan
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China
| | - Qianqian Mi
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China
| | - Yiru Mao
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China
| | - Chao Zhao
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China
| | - Xiangrong Tian
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Forestry, Northwest A&F University, Yangling, People's Republic of China
| | - Wei Liu
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China
| | - Lili Huang
- National Key Laboratory of Crop Improvement for Stress Tolerance and Production, Northwest A&F University, Yangling, People's Republic of China
- College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China
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Wang Y, Chen J, Du J, Lei L, Zhao B, Bai Y, Chen D, Wang X, Chen C. The Determination of Polymyxin B in Critically Ill Patients by the HPLC-MS/MS Method. Int J Anal Chem 2023; 2023:6674009. [PMID: 37063108 PMCID: PMC10104742 DOI: 10.1155/2023/6674009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 02/20/2023] [Accepted: 03/07/2023] [Indexed: 04/18/2023] Open
Abstract
Polymyxin B (PB) is a dose-dependent drug used to treat multidrug-resistantgram-negative bacteria, for which a suitable method is needed to determine clinical samples. A simple, economical, and efficient high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) method was developed and validated for polymyxin B1 (PB1), polymyxin B1-Ile (PB1-I), polymyxin B2 (PB2), and polymyxin B3 (PB3) in human plasma. Chromatographic column was Waters BEH C18 column (2.1 × 50 mm, 1.7 μm). Phase A was water with 0.2% formic acid (FA), and phase B was acetonitrile containing 0.2% FA. The elution method is gradient elutio. The total analysis time was 5 min. The pretreatment method involved protein precipitation using acetonitrile containing 0.2% trifluoroacetic acid and 0.1% FA as the precipitant. The recovery rate was 92-99%. The total quantity of PB1 and PB1-I was measured in the linear range of 100-8000 ng/mL. Simultaneously, the total amounts of PB2 and PB3 were measured in the linear range of 11.9-948.5 ng/mL. This validated method was successfully applied to the pharmacokinetics of PB in critically ill patients.
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Affiliation(s)
- Yirong Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, Guangdong, China
| | - Jingchun Chen
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, Guangdong, China
| | - Jinpan Du
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, Guangdong, China
| | - Liming Lei
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Boxin Zhao
- Department of Pharmacy, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yunpeng Bai
- Center of Scientific Research, Maoming People's Hospital, Maoming 525000, China
| | - Dong Chen
- School of Medicine, South China University of Technology, Guangzhou 510006, China
| | - Xipei Wang
- Research Center of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
- Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China
| | - Chunbo Chen
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, Guangdong, China
- Department of Intensive Care Unit of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
- Department of Critical Care Medicine, Shenzhen People's Hospital, The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of South University of Science and Technology, Shenzhen 518020, China
- Department of Emergency, Maoming People's Hospital, Maoming 525000, China
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Yuan H, Yu S, Chai G, Liu J, Zhou Q(T. An LC-MS/MS method for simultaneous analysis of the cystic fibrosis therapeutic drugs colistin, ivacaftor and ciprofloxacin. J Pharm Anal 2021; 11:732-738. [PMID: 35028178 PMCID: PMC8740159 DOI: 10.1016/j.jpha.2021.02.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 01/25/2021] [Accepted: 02/22/2021] [Indexed: 11/30/2022] Open
Abstract
Inhaled antibiotics such as colistin and ciprofloxacin are increasingly used to treat bacterial lung infections in cystic fibrosis patients. In this study, we established and validated a new HPLC-MS/MS method that could simultaneously detect drug concentrations of ciprofloxacin, colistin and ivacaftor in rat plasma, human epithelial cell lysate, cell culture medium, and drug transport media. An aliquot of 200 μL drug-containing rat plasma or cell culture medium was treated with 600 μL of extraction solution (acetonitrile containing 0.1% formic acid and 0.2% trifluoroacetic acid (TFA)). The addition of 0.2% TFA helped to break the drug-protein bonds. Moreover, the addition of 0.1% formic acid to the transport medium and cell lysate samples could significantly improve the response and reproducibility. After vortexing and centrifuging, the sample components were analyzed by HPLC-MS/MS. The multiple reaction monitoring mode was used to detect the following transitions: 585.5-101.1 (colistin A), 578.5-101.1 (colistin B), 393.2-337.2 (ivacaftor), 332.2-314.2 (ciprofloxacin), 602.3-101.1 (polymyxin B1 as internal standard (IS)) and 595.4-101.1 (polymyxin B2 as IS). The running time of a single sample was only 6 min, making this a time-efficient method. Linear correlations were found for colistin A at 0.029-5.82 μg/mL, colistin B at 0.016-3.14 μg/mL, ivacaftor at 0.05-10.0 μg/mL, and ciprofloxacin at 0.043-8.58 μg/mL. Accuracy, precision, and stability of the method were within the acceptable range. This method would be highly useful for research on cytotoxicity, animal pharmacokinetics, and in vitro drug delivery.
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Affiliation(s)
- Huiya Yuan
- School of Forensic Medicine, China Medical University, Shenyang, 110122, China
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
| | - Shihui Yu
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
| | - Guihong Chai
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
| | - Junting Liu
- School of Forensic Medicine, China Medical University, Shenyang, 110122, China
- Corresponding author.
| | - Qi (Tony) Zhou
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, IN, 47907, USA
- Corresponding author.;
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Mülner P, Schwarz E, Dietel K, Herfort S, Jähne J, Lasch P, Cernava T, Berg G, Vater J. Fusaricidins, Polymyxins and Volatiles Produced by Paenibacillus polymyxa Strains DSM 32871 and M1. Pathogens 2021; 10:1485. [PMID: 34832640 PMCID: PMC8621861 DOI: 10.3390/pathogens10111485] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/09/2021] [Accepted: 11/09/2021] [Indexed: 01/18/2023] Open
Abstract
Paenibacilli are efficient producers of potent agents against bacterial and fungal pathogens, which are of great interest both for therapeutic applications in medicine as well as in agrobiotechnology. Lipopeptides produced by such organisms play a major role in their potential to inactivate pathogens. In this work we investigated two lipopeptide complexes, the fusaricidins and the polymyxins, produced by Paenibacillus polymyxa strains DSM 32871 and M1 by MALDI-TOF mass spectrometry. The fusaricidins show potent antifungal activities and are distinguished by an unusual variability. For strain DSM 32871 we identified numerous yet unknown variants mass spectrometrically. DSM 32871 produces polymyxins of type E (colistins), while M1 forms polymyxins P. For both strains, novel but not yet completely characterized polymyxin species were detected, which possibly are glycosylated. These compounds may be of interest therapeutically, because polymyxins have gained increasing attention as last-resort antibiotics against multiresistant pathogenic Gram-negative bacteria. In addition, the volatilomes of DSM 32781 and M1 were investigated with a GC-MS approach using different cultivation media. Production of volatile organic compounds (VOCs) was strain and medium dependent. In particular, strain M1 manifested as an efficient VOC-producer that exhibited formation of 25 volatiles in total. A characteristic feature of Paenibacilli is the formation of volatile pyrazine derivatives.
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Affiliation(s)
- Pascal Mülner
- ABITEP GmbH, Glienicker Weg 185, 12489 Berlin, Germany; (P.M.); (E.S.); (K.D.)
- Institute of Environmental Biotechnology, Graz University of Technology, Petergasse 12, 8010 Graz, Austria; (T.C.); (G.B.)
| | - Elisa Schwarz
- ABITEP GmbH, Glienicker Weg 185, 12489 Berlin, Germany; (P.M.); (E.S.); (K.D.)
| | - Kristin Dietel
- ABITEP GmbH, Glienicker Weg 185, 12489 Berlin, Germany; (P.M.); (E.S.); (K.D.)
| | - Stefanie Herfort
- Robert Koch-Institut, ZBS6, Proteomics and Spectroscopy, Seestr 10, 13353 Berlin, Germany; (S.H.); (J.J.); (P.L.)
| | - Jennifer Jähne
- Robert Koch-Institut, ZBS6, Proteomics and Spectroscopy, Seestr 10, 13353 Berlin, Germany; (S.H.); (J.J.); (P.L.)
| | - Peter Lasch
- Robert Koch-Institut, ZBS6, Proteomics and Spectroscopy, Seestr 10, 13353 Berlin, Germany; (S.H.); (J.J.); (P.L.)
| | - Tomislav Cernava
- Institute of Environmental Biotechnology, Graz University of Technology, Petergasse 12, 8010 Graz, Austria; (T.C.); (G.B.)
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, Petergasse 12, 8010 Graz, Austria; (T.C.); (G.B.)
| | - Joachim Vater
- Robert Koch-Institut, ZBS6, Proteomics and Spectroscopy, Seestr 10, 13353 Berlin, Germany; (S.H.); (J.J.); (P.L.)
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A new PKPD model to characterize the inoculum effect of Acinetobacter baumannii on polymyxin B in vitro. Antimicrob Agents Chemother 2021; 66:e0178921. [PMID: 34780268 DOI: 10.1128/aac.01789-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The inoculum effect (i.e., reduction in antimicrobial activity at large starting inoculum) is a phenomenon described for various pathogens. Since limited data exist regarding inoculum effect of Acinetobacter baumannii, we evaluated killing of A. baumannii by polymyxin B, a last-resort antibiotic, at several starting inocula and developed a PKPD model to capture this phenomenon. In vitro static time-kill experiments were performed using polymyxin B at concentrations ranging from 0.125 to 128 mg/L against a clinical A. baumannii isolate at four starting inocula from 105 to 108 CFU/mL. Samples were collected up to 30 h to quantify the viable bacterial burden and were simultaneously modeled in the NONMEM software program. The expression of polymyxin B resistance genes (lpxACD, pmrCAB and wzc), and genetic modifications were studied by RT-qPCR and DNA sequencing experiments, respectively. The PKPD model included a single homogeneous bacterial population with adaptive resistance. Polymyxin B effect was modelled as a sigmoidal Emax model and the inoculum effect as an increase of polymyxin B EC50 with increasing starting inoculum using a power function. Polymyxin B displayed a reduced activity as the starting inoculum increased: a 20-fold increase of polymyxin B EC50 was observed between the lowest and the highest inoculum. No effects of polymyxin B and inoculum size were observed on the studied genes. The proposed PKPD model successfully described and predicted the pronounced in vitro inoculum effect of A. baumannii on polymyxin B activity. These results should be further validated using other bacteria/antibiotic combinations and in vivo models.
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Abstract
Antibiotic resistance is a major global health challenge and, worryingly, several key Gram negative pathogens can become resistant to most currently available antibiotics. Polymyxins have been revived as a last-line therapeutic option for the treatment of infections caused by multidrug-resistant Gram negative bacteria, in particular Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacterales. Polymyxins were first discovered in the late 1940s but were abandoned soon after their approval in the late 1950s as a result of toxicities (e.g., nephrotoxicity) and the availability of "safer" antibiotics approved at that time. Therefore, knowledge on polymyxins had been scarce until recently, when enormous efforts have been made by several research teams around the world to elucidate the chemical, microbiological, pharmacokinetic/pharmacodynamic, and toxicological properties of polymyxins. One of the major achievements is the development of the first scientifically based dosage regimens for colistin that are crucial to ensure its safe and effective use in patients. Although the guideline has not been developed for polymyxin B, a large clinical trial is currently being conducted to optimize its clinical use. Importantly, several novel, safer polymyxin-like lipopeptides are developed to overcome the nephrotoxicity, poor efficacy against pulmonary infections, and narrow therapeutic windows of the currently used polymyxin B and colistin. This review discusses the latest achievements on polymyxins and highlights the major challenges ahead in optimizing their clinical use and discovering new-generation polymyxins. To save lives from the deadly infections caused by Gram negative "superbugs," every effort must be made to improve the clinical utility of the last-line polymyxins. SIGNIFICANCE STATEMENT: Antimicrobial resistance poses a significant threat to global health. The increasing prevalence of multidrug-resistant (MDR) bacterial infections has been highlighted by leading global health organizations and authorities. Polymyxins are a last-line defense against difficult-to-treat MDR Gram negative pathogens. Unfortunately, the pharmacological information on polymyxins was very limited until recently. This review provides a comprehensive overview on the major achievements and challenges in polymyxin pharmacology and clinical use and how the recent findings have been employed to improve clinical practice worldwide.
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Affiliation(s)
- Sue C Nang
- Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Victoria, Australia (S.C.N., M.A.K.A., J.L.); Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia (T.V.); and Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana (Q.T.Z.)
| | - Mohammad A K Azad
- Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Victoria, Australia (S.C.N., M.A.K.A., J.L.); Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia (T.V.); and Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana (Q.T.Z.)
| | - Tony Velkov
- Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Victoria, Australia (S.C.N., M.A.K.A., J.L.); Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia (T.V.); and Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana (Q.T.Z.)
| | - Qi Tony Zhou
- Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Victoria, Australia (S.C.N., M.A.K.A., J.L.); Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia (T.V.); and Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana (Q.T.Z.)
| | - Jian Li
- Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Victoria, Australia (S.C.N., M.A.K.A., J.L.); Department of Pharmacology and Therapeutics, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia (T.V.); and Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana (Q.T.Z.)
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Rao X, Jiang H, Li L, Xiang F, Liu Z. A cost-effective and rapid quantitative test of polymyxin B sulphate with a simple and portable pressure meter readout. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:3484-3489. [PMID: 32672257 DOI: 10.1039/d0ay00935k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Any signals, if their intensities have a simple functional relationship with analyte concentration, can be applied for analytical purposes. Among them, pressure measurement as a signalling technique has been extensively utilized to develop portable and quantitative bioanalysis, with the advantages of highly sensitive detection of a variety of biomedical targets. In this contribution, it was found that polymyxin B sulphate (PMB) could significantly inhibit the catalytic ability of platinum nanoparticles (PtNPs) prepared in different protocols in the H2O2 breakdown reaction. By employing sodium citrate as the reducing agent to prepare the platinum nanoparticles (C-PtNPs) as an example and monitoring the pressure signal changes of the C-PtNP catalyzed H2O2 breakdown against the reaction time, a sensitive, cost-effective, rapid and reliable analysis method for PMB is established on the basis of the pressure signal readout. The proposed method has a detection limit of 28.6 nM and can selectively detect PMB in both POLY-MxB powder injection and human urine samples, demonstrating its potential in bioanalysis, which would be significant to address biological, clinical and medicinal requirements.
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Affiliation(s)
- Xinyue Rao
- Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
| | - Huan Jiang
- Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
| | - Ling Li
- Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
| | - Feng Xiang
- Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
| | - Zhongde Liu
- Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
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History, Chemistry and Antibacterial Spectrum. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1145:15-36. [DOI: 10.1007/978-3-030-16373-0_3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Galea CA, Han M, Zhu Y, Roberts K, Wang J, Thompson PE, L J, Velkov T. Characterization of the Polymyxin D Synthetase Biosynthetic Cluster and Product Profile of Paenibacillus polymyxa ATCC 10401. JOURNAL OF NATURAL PRODUCTS 2017; 80:1264-1274. [PMID: 28463513 DOI: 10.1021/acs.jnatprod.6b00807] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The increasing prevalence of polymyxin-resistant bacteria has stimulated the search for improved polymyxin lipopeptides. Here we describe the sequence and product profile for polymyxin D nonribosomal peptide synthetase from Paenibacillus polymyxa ATCC 10401. The polymyxin D synthase gene cluster comprised five genes that encoded ABC transporters (pmxC and pmxD) and enzymes responsible for the biosynthesis of polymyxin D (pmxA, pmxB, and pmxE). Unlike polymyxins B and E, polymyxin D contains d-Ser at position 3 as opposed to l-α,γ-diaminobutyric acid and has an l-Thr at position 7 rather than l-Leu. Module 3 of pmxE harbored an auxiliary epimerization domain that catalyzes the conversion of l-Ser to the d-form. Structural modeling suggested that the adenylation domains of module 3 in PmxE and modules 6 and 7 in PmxA could bind amino acids with larger side chains than their preferred substrate. Feeding individual amino acids into the culture media not only affected production of polymyxins D1 and D2 but also led to the incorporation of different amino acids at positions 3, 6, and 7 of polymyxin D. Interestingly, the unnatural polymyxin analogues did not show antibiotic activity against a panel of Gram-negative clinical isolates, while the natural polymyxins D1 and D2 exhibited excellent in vitro antibacterial activity and were efficacious against Klebsiella pneumoniae and Acinetobacter baumannii in a mouse blood infection model. The results demonstrate the excellent antibacterial activity of these unusual d-Ser3 polymxyins and underscore the possibility of incorporating alternate amino acids at positions 3, 6, and 7 of polymyxin D via manipulation of the polymyxin nonribosomal biosynthetic machinery.
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Affiliation(s)
| | - Meiling Han
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University , Clayton, Victoria 3800, Australia
| | - Yan Zhu
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University , Clayton, Victoria 3800, Australia
| | | | - Jiping Wang
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University , Clayton, Victoria 3800, Australia
| | | | - Jian L
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University , Clayton, Victoria 3800, Australia
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13
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Roberts KD, Azad MAK, Wang J, Horne AS, Thompson PE, Nation RL, Velkov T, Li J. Antimicrobial Activity and Toxicity of the Major Lipopeptide Components of Polymyxin B and Colistin: Last-line Antibiotics against Multidrug-Resistant Gram-negative Bacteria. ACS Infect Dis 2015; 1:568-575. [PMID: 27525307 DOI: 10.1021/acsinfecdis.5b00085] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Polymyxin B and colistin are currently used as a 'last-line' treatment for multidrug-resistant Gram-negative bacteria. However very little is known about the pharmacological differences between polymyxin B1, polymyxin B2, colistin A, colistin B, the major cyclic lipopeptides components present in polymyxin B and colistin products. Here, we report on the in vitro and in vivo antimicrobial activity and toxicity of these major lipopeptide components. All four lipopeptides had comparable MICs (<0.125-4 mg/L) against a panel of clinical Gram-negative isolates. They also had comparable in vivo antimicrobial activity (Δlog10 CFU/mL >-3) and nephrotoxicity (mild to moderate histological damage) in mouse models. However, polymyxin B1 and colistin A showed significantly higher (> 3-fold) in vitro apoptotic effect on human kidney proximal tubular HK-2 cells than polymyxin B2 and colistin B, respectively. Compared to the commercial polymyxin and colistin products, the individual lipopeptide components had slightly more in vivo antimicrobial activity. Our results highlight the need to re-assess pharmacopoeial standards for polymyxins B and colistin and to standardize the composition of the different commercial products of polymyxin antibiotics.
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Affiliation(s)
- Kade D. Roberts
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
| | - Mohammad A. K. Azad
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
| | - Jiping Wang
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
| | - Andrew S. Horne
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
| | - Philip E. Thompson
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
| | - Roger L. Nation
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
| | - Tony Velkov
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
| | - Jian Li
- Drug
Delivery, Disposition and Dynamics, and ‡Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal
Parade, Parkville 3052, Victoria, Australia
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14
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Tambadou F, Caradec T, Gagez AL, Bonnet A, Sopéna V, Bridiau N, Thiéry V, Didelot S, Barthélémy C, Chevrot R. Characterization of the colistin (polymyxin E1 and E2) biosynthetic gene cluster. Arch Microbiol 2015; 197:521-32. [PMID: 25609230 DOI: 10.1007/s00203-015-1084-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 01/08/2015] [Accepted: 01/13/2015] [Indexed: 10/24/2022]
Abstract
Colistin is a mixture of polymyxin E1 and E2, bactericidal pentacationic lipopeptides used to treat infections caused by Gram-negative pathogens such as Pseudomonas aeruginosa and Klebsiella pneumoniae. Industrial production of colistin is obtained by a fermentation process of the natural producer Paenibacillus polymyxa var colistinus. NonRibosomal peptide synthetases (NRPS) coding the biosynthesis of polymyxins A, B and P have been recently described, rendering thereof the improvement of their production possible. However, the colistin biosynthesis pathway was not published so far. In this study, a Paenibacillus alvei has been identified by biochemical (Api 50 CH system) and molecular (16S rDNA sequencing) methods. Its culture supernatant displayed inhibitory activity against Gram-negative bacteria (P. aeruginosa, K. pneumoniae, Salmonella spp.). Two polymyxins, E1 and E2, were recovered from the supernatant and were characterized by high resolution LC-MS. A genomic library (960 clones) was constructed to identify the gene cluster responsible for biosynthesis of polymyxins. Selection of the clones harbouring the sequences of interest was obtained by a simple PCR-based screening. We used primers targeting NRPS sequences leading to the incorporation of amino acids present in polymyxins E. The sequences from three clones of interest were assembled on 50.4 kb. Thus, five open reading frames corresponding to a new NRPS gene cluster of 41 kb were identified. In silico, analyses revealed the presence of three NRPS implicated in the biosynthesis of polymyxins E. This work provides insightful information on colistin biosynthesis and might contribute to future drug developments in this group of antibiotics.
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Affiliation(s)
- Fatoumata Tambadou
- Laboratoire Littoral Environnement et Sociétés, LIENSs - UMR 7266 - CNRS, Université de La Rochelle, Avenue Michel Crépeau, 17042, La Rochelle Cedex 1, France
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15
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New LS, Lim TP, Oh JW, Cheah GJS, Kwa AL, Chan ECY. Optimizing hollow-fiber-based pharmacokinetic assay via chemical stability study to account for inaccurate simulated drug clearance of rifampicin. Anal Bioanal Chem 2012. [DOI: 10.1007/s00216-012-6549-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Shaheen M, Li J, Ross AC, Vederas JC, Jensen SE. Paenibacillus polymyxa PKB1 produces variants of polymyxin B-type antibiotics. ACTA ACUST UNITED AC 2012; 18:1640-8. [PMID: 22195566 DOI: 10.1016/j.chembiol.2011.09.017] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 09/15/2011] [Accepted: 09/26/2011] [Indexed: 11/17/2022]
Abstract
Polymyxins are cationic lipopeptide antibiotics active against many species of Gram-negative bacteria. We sequenced the gene cluster for polymyxin biosynthesis from Paenibacillus polymyxa PKB1. The 40.8 kb gene cluster comprises three nonribosomal peptide synthetase-encoding genes and two ABC transporter-like genes. Disruption of a peptide synthetase gene abolished all antibiotic production, whereas deletion of one or both transporter genes only reduced antibiotic production. Computational analysis of the peptide synthetase modules suggested that the enzyme system produces variant forms of polymyxin B (1 and 2), with D-2,4-diaminobutyrate instead of L-2,4-diaminobutyrate in amino acid position 3. Two antibacterial metabolites were resolved by HPLC and identified by high-resolution mass spectrometry and MS/MS sequencing as the expected variants 3 and 4 of polymyxin B(1) (1) and B(2) (2). Stereochemical analysis confirmed the presence of both D-2,4-diaminobutyrate and L-2,4-diaminobutyrate residues.
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Affiliation(s)
- Mohamed Shaheen
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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17
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Colistin A and colistin B among inhibitory substances of Paenibacillus polymyxa JB05-01-1. Arch Microbiol 2011; 194:363-70. [DOI: 10.1007/s00203-011-0764-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2011] [Revised: 09/25/2011] [Accepted: 10/03/2011] [Indexed: 10/15/2022]
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18
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Deng Y, Lu Z, Bi H, Lu F, Zhang C, Bie X. Isolation and characterization of peptide antibiotics LI-F04 and polymyxin B6 produced by Paenibacillus polymyxa strain JSa-9. Peptides 2011; 32:1917-23. [PMID: 21864605 DOI: 10.1016/j.peptides.2011.08.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Revised: 08/02/2011] [Accepted: 08/02/2011] [Indexed: 10/17/2022]
Abstract
Paenibacillus polymyxa JSa-9 had been found to produce five cyclic LI-F type antibiotics which were released into culture medium in accordance with our previous report. In this study, another three kinds of antagonistic compounds were extracted from P. polymyxa JSa-9 cell pellets and (or) spores by methanol. Using high performance liquid chromatography (HPLC) method, two antagonistic fractions were separated and collected from the methanol extract. One showed inhibition against Escherichia coli and Staphylococcus aureus, while the other was active against Aspergillus niger and S. aureus. By means of electrospray ionization mass spectroscopy (ESI-MS), infrared spectroscopy (IR), and amino acid analysis, two kinds of compounds from fraction B with molecular masses of 901 and 915Da were characterized as the linear lipopeptide analogs of antibiotics LI-F04a and LI-F04b, respectively. Another antimicrobial substance from fraction A could be attributed to polymyxin B(6).
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Affiliation(s)
- Yang Deng
- College of Food Science and Technology, Nanjing Agricultural University, Key Laboratory of Food Processing and Quality Control, Ministry of Agriculture of China, 1 Weigang, Nanjing 210095, China
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19
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Van den Bossche L, Van Schepdael A, Chopra S, Hoogmartens J, Adams E. Identification of impurities in polymyxin B and colistin bulk sample using liquid chromatography coupled to mass spectrometry. Talanta 2010; 83:1521-9. [PMID: 21238747 DOI: 10.1016/j.talanta.2010.11.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 11/09/2010] [Accepted: 11/21/2010] [Indexed: 11/17/2022]
Abstract
The European Pharmacopoeia (Ph. Eur.) describes liquid chromatography-ultraviolet (LC-UV) methods using C(18) stationary phases for the analysis of polymyxin B and colistin. Several unknown impurities were detected in commercial samples of those polypeptide complexes. However, the Ph. Eur. does not specify any related substances for polymyxin B and colistin. Since both methods use non-volatile buffers, the mobile phases were incompatible with mass spectrometry (MS). For the identification of related substances in bulk samples by LC/MS, volatile mobile phase systems were developed. However, the LC/MS methods (with volatile additives) showed inferior chromatographic separation compared to the LC-UV method (with non-volatile additives). Moreover, previously identified impurities by LC/MS could not be assigned in LC-UV methods as the separation in both systems was different. In this study, known impurities were traced in the LC-UV methods and new impurities present in polymyxin B and colistin bulk samples were characterized. To achieve this, each peak from the non-volatile system was collected separately and reinjected into an LC system with a volatile mobile phase coupled to MS. This way, collected impurity peaks were rechromatographed on a reversed phase column in order to separate the analyte from the buffer salts. Using this method, out of 39 peaks, five novel related substances were characterized in a polymyxin B bulk sample. Fourteen impurities, which were already reported in the literature were traced as good as possible in the LC-UV method. In the case of colistin, a total of 36 peaks were investigated, among which four new compounds. Additionally, 30 known impurities were traced in the LC-UV method.
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20
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Angel Bello López M, Callejón Mochón M, Fernández-Torres R, Villar Navarro M, Antonio Ocaña González J. Rapid Flow-Injection Method for the Determination of Colistin by Sensitized Chemiluminescence Using the Acidic Permanganate–Sulfite System. ANAL LETT 2009. [DOI: 10.1080/00032710902954417] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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21
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Determination of colistin in human plasma, urine and other biological samples using LC–MS/MS. J Chromatogr B Analyt Technol Biomed Life Sci 2008; 862:205-12. [DOI: 10.1016/j.jchromb.2007.12.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 11/29/2007] [Accepted: 12/11/2007] [Indexed: 11/22/2022]
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22
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Okimura K, Ohki K, Sato Y, Ohnishi K, Uchida Y, Sakura N. Chemical Conversion of Natural Polymyxin B and Colistin to TheirN-Terminal Derivatives. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2007. [DOI: 10.1246/bcsj.80.543] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Mayumi T, Kato H, Kawasaki Y, Harada KI. Formation of diagnostic product ions from cyanobacterial cyclic peptides by the two-bond fission mechanism using ion trap liquid chromatography/multi-stage mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:1025-33. [PMID: 17318805 DOI: 10.1002/rcm.2920] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Product ions obtained by tandem mass spectrometry (MS/MS) are quite effective for the amino acid sequencing of linear peptides. However, in the case of cyclic peptides, the fragmentation pattern is complicated because the cleavages occur randomly and product ions are generated as a(n), b(n), c(n), x(n), y(n) and z(n) series ions; therefore, the authors have never obtained sufficient sequence information. In order to overcome this problem, we applied ion trap liquid chromatography/multi-stage mass spectrometry (LC/MS(n)) and characterized the product ions obtained from anabaenopeptins and aeruginopeptins as the cyclic peptides. For the anabaenopeptins, MS(2) analysis did not provide sufficient sequence information on the cyclic structure, and MS(3) analysis was applied to sequence the constituent amino acids. Diagnostic product ions were obtained by the MS(3) analysis and were quite effective for obtaining the sequence information of the constituent amino acids. MS(2) analysis was, however, sufficient to obtain the sequence information of the aeruginopeptins. In both cases, the resulting product ions obtained from the cyclic structures were formed by the two-bond fission mechanism of the precursor ion, in which an initial fission of the cyclic structure to a linear one and subsequent fission(s) at the peptide bonds are included. The fragmentations were similar for the structurally related compounds, indicating that the cleavages occurred at definite peptide bonds. In addition, the resulting product ions are generated as b(n) series ions and the mass difference facilitates the amino acid sequencing. Thus, ion trap LC/MS(n) provides sequence information, and the resulting product ions are reproducible among the structurally related compounds and reliable for the sequencing of the constituent amino acids of the cyclic structure.
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Affiliation(s)
- Tsuyoshi Mayumi
- Graduate School of Environmental and Human Science, Meijo University, Tempaku, Nagoya 468-8503, Japan.
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24
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He Z, Kisla D, Zhang L, Yuan C, Green-Church KB, Yousef AE. Isolation and identification of a Paenibacillus polymyxa strain that coproduces a novel lantibiotic and polymyxin. Appl Environ Microbiol 2006; 73:168-78. [PMID: 17071789 PMCID: PMC1797129 DOI: 10.1128/aem.02023-06] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A new bacterial strain, displaying potent antimicrobial properties against gram-negative and gram-positive pathogenic bacteria, was isolated from food. Based on its phenotypical and biochemical properties as well as its 16S rRNA gene sequence, the bacterium was identified as Paenibacillus polymyxa and it was designated as strain OSY-DF. The antimicrobials produced by this strain were isolated from the fermentation broth and subsequently analyzed by liquid chromatography-mass spectrometry. Two antimicrobials were found: a known antibiotic, polymyxin E1, which is active against gram-negative bacteria, and an unknown 2,983-Da compound showing activity against gram-positive bacteria. The latter was purified to homogeneity, and its antimicrobial potency and proteinaceous nature were confirmed. The antimicrobial peptide, designated paenibacillin, is active against a broad range of food-borne pathogenic and spoilage bacteria, including Bacillus spp., Clostridium sporogenes, Lactobacillus spp., Lactococcus lactis, Leuconostoc mesenteroides, Listeria spp., Pediococcus cerevisiae, Staphylococcus aureus, and Streptococcus agalactiae. Furthermore, it possesses the physico-chemical properties of an ideal antimicrobial agent in terms of water solubility, thermal resistance, and stability against acid/alkali (pH 2.0 to 9.0) treatment. Edman degradation, mass spectroscopy, and nuclear magnetic resonance were used to sequence native and chemically modified paenibacillin. While details of the tentative sequence need to be elucidated in future work, the peptide was unequivocally characterized as a novel lantibiotic, with a high degree of posttranslational modifications. The coproduction of polymyxin E1 and a lantibiotic is a finding that has not been reported earlier. The new strain and associated peptide are potentially useful in food and medical applications.
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Affiliation(s)
- Zengguo He
- Parker Food Science Building, The Ohio State University, 2015 Fyffe Road, Columbus, OH 43210, USA
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25
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Pittenauer E, Zehl M, Belgacem O, Raptakis E, Mistrik R, Allmaier G. Comparison of CID spectra of singly charged polypeptide antibiotic precursor ions obtained by positive-ion vacuum MALDI IT/RTOF and TOF/RTOF, AP-MALDI-IT and ESI-IT mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2006; 41:421-47. [PMID: 16604520 DOI: 10.1002/jms.1032] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Various classes of polypeptide antibiotics, including blocked linear peptides (gramicidin D), side-chain-cyclized peptides (bacitracin, viomycin, capreomycin), side-chain-cyclized depsipeptides (virginiamycin S), real cyclic peptides (tyrocidin, gramcidin S) and side-chain-cyclized lipopeptides (polymyxin B and E, amfomycin), were investigated by low-energy collision induced dissociation (LE-CID) as well as high-energy CID (HE-CID). Ion trap (IT) based instruments with different desorption/ionization techniques such as electrospray ionization (ESI), atmospheric pressure matrix-assisted laser desorption/ionization (AP-MALDI) and vacuum MALDI (vMALDI) as well as a vMALDI-time-of-flight (TOF)/curved field-reflectron instrument fitted with a gas collision cell were used. For optimum comparability of data from different IT instruments, the CID conditions were standardized and only singly charged precursor ions were considered. Additionally, HE-CID data obtained from the TOF-based instrument were acquired and compared with LE-CID data from ITs. Major differences between trap-based and TOF-based CID data are that the latter data set lacks abundant additional loss of small neutrals (e.g. ammonia, water) but contains product ions down to the immonium-ion-type region, thereby allowing the detection of even single amino-acid (even unusual amino acids) substitutions. For several polypeptide antibiotics, mass spectrometric as well as tandem mass spectrometric data are shown and discussed for the first time, and some yet undescribed minor components are also reported. De novo sequencing of unusually linked minor components of (e.g. cyclic) polypeptides is practically impossible without knowledge of the exact structure and fragmentation behavior of the major components. Finally, the described standardized CID condition constitutes a basic prerequisite for creating a searchable, annotated MS(n)-database of bioactive compounds. The applied desorption/ionization techniques showed no significant influence on the type of product ions (neglecting relative abundances of product ions formed) observed, and therefore the type of analyzer connected with the CID process mainly determines the type of fragment ions.
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Affiliation(s)
- Ernst Pittenauer
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Vienna, Austria
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26
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Morales-Muñoz S, de Castro MDL. Dynamic ultrasound-assisted extraction of colistin from feeds with on-line pre-column derivatization and liquid chromatography-fluorimetric detection. J Chromatogr A 2005; 1066:1-7. [PMID: 15794548 DOI: 10.1016/j.chroma.2005.01.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A dynamic ultrasound-assisted extraction (UAE) method with on-line pre-column derivatization/high performance liquid chromatography (HPLC) and fluorimetric detection is proposed for the analysis of colistin in feed. A flow injection manifold is used for the development of the extraction and derivatization steps and for interfacing them with the separation/detection step, thus providing an on-line approach with the advantage of minimum sample handling. The derivatization was performed with ortho-phthaldialdehyde and 2-mercaptoethanol. The optimum conditions for colistin extraction and formation of the fluorescent derivative have been obtained by experimental design methodology. The use of a high-intensity probe sonication makes UAE an expeditious (7 min versus > 1 h) and efficient (93.1-98.2% versus 87.5-94% of recovery) alternative as compared with extraction using an ultrasonic bath. The within-laboratory reproducibility and repeatability, expressed as percentage of relative standard deviation, were 5.2 and 5.8, respectively.
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Affiliation(s)
- S Morales-Muñoz
- Department of Analytical Chemistry, University of Córdoba, Marie Curie Building Annex, Campus of Rabanales, E-14071 Córdoba, Spain.
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27
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Eichhorn P, Pérez S, Bechtholt A, Aga DS. Fragmentation studies on the antibiotic avilamycin A using ion trap mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2004; 39:1541-1553. [PMID: 15578738 DOI: 10.1002/jms.760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A comprehensive study on the fragmentation pattern of the antimicrobial growth promoter avilamycin A was conducted in a quadrupole ion trap mass spectrometer equipped with an electrospray ionization (ESI) source. Performing multiple-stage experiments on the deprotonated molecule (m/z 1401) and its principal product ions showed that a sequential shortening of the oligosaccharide backbone took place, which can be attributed to the localization of the negative charge in the terminal dichloroisoeverninic acid. Under (+)-ESI conditions, avilamycin A readily formed an intense sodium-cationized molecule, [M + Na](+) (m/z 1425). Structural elucidation of the second-, third- and fourth-generation fragment ions revealed that all of the structures shared a common molecular portion comprising a central monosaccharide. This observation allowed us to assign confidently the complexation site of the alkali metal cation. In addition to the monosodiated molecule, the full-scan mass spectral acquisition also yielded a less abundant disodiated molecule, [M - H + 2Na](+) (m/z 1447). Multiple-stage experiments on this ion indicated that the second sodium ion compensates for the negative charge located at either of two positions within the molecule. While deprotonation of the phenolic hydroxyl group in the dichloroisoeverninic acid moiety was suggested to be driven by charge stabilization in the aromatic ring (in analogy with the deprotonated molecule in the (-)-ESI mode), the deprotonation at an alpha-carbon of an ester side-chain substituent in the oligosaccharide part was believed to provide a stable chelation-like coordination site for the cation.
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Affiliation(s)
- Peter Eichhorn
- Chemistry Department, State University of New York at Buffalo, 611 Natural Science Complex, Buffalo, New York 14260, USA
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28
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de Visser PC, Govaerts C, van Hooft PAV, Overkleeft HS, Van Schepdael A, Hoogmartens J. Liquid chromatography–mass spectrometry study towards the pH and temperature-induced N-acyl migration in polymyxin B. J Chromatogr A 2004; 1058:183-9. [PMID: 15595666 DOI: 10.1016/j.chroma.2004.05.104] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In the course of the synthesis and purification of new polymyxins and analogues, formation of a by-product with identical mass was observed and it was believed that this might be the result of acyl migration from the Nalpha- to the Ngamma-position of residue alpha,-gamma-diaminobutyric acid 1 (Dab1) under acidic conditions. Therefore, a LC-MS/MS study was initiated to establish the stability of polymyxin B3 in aqueous solution at room temperature and 60 degrees C, as well as different pH values (i.e. 1.4, 4.4 and 7.4). It was shown that the by-product, which is actually formed in the course of the purification of polymyxin B3 after evaporation in acidic medium, has a retention time similar to Ngamma-polymyxin B3. Acyl-migration occurred most rapidly at 60 degrees C and pH 7.4. Furthermore, it was established that migration of the acyl from the Nalpha- to the Ngamma-position of residue Dab1 is reversible and that the equilibrium seems to be in favor of the Nalpha-acylated compound.
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Affiliation(s)
- Peter C de Visser
- Leiden Institute of Chemistry, Leiden University, 2300 RA Leiden, The Netherlands
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Tozzi C, Anfossi L, Giraudi G. Affinity chromatography techniques based on the immobilisation of peptides exhibiting specific binding activity. J Chromatogr B Analyt Technol Biomed Life Sci 2004; 797:289-304. [PMID: 14630156 DOI: 10.1016/s1570-0232(03)00481-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Affinity chromatography is one of the powerful techniques in selective purification and isolation of a great number of compounds. New challenges in scientific research, such as high-throughput systems, isolation procedures that allow to obtain a single substance from a complex matrix in high degree of purity, low costs and wide availability, have led to the discovery of new tailor-made synthetic recognition systems. In this review the design, synthesis, purification and characterisation of peptides with recognition properties are discussed. Applications of peptide ligands are described and analytical tools mentioned.
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Affiliation(s)
- Cinzia Tozzi
- Department of Analytical Chemistry, University of Turin, Via P. Giuria 5, 10125 Turin, Italy.
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Stefanowicz P. Electrospray mass spectrometry and tandem mass spectrometry of the natural mixture of cyclic peptides from linseed. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2004; 10:665-671. [PMID: 15531800 DOI: 10.1255/ejms.657] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The cyclic peptides from linseed are composed exclusively of the hydrophobic amino acids: Phe, Leu, Ile, Val, Met, Pro, and Trp. Because these compounds does not contain functional groups which undergo easily protonation or deprotonation. their ionization in solvents used usually for peptide analysis is not efficient. A rapid and sensitive procedure for detection and structure elucidation of the cyclic peptides based on ionization with Na+ and NH4+ ions. A cationisation of methionine containing peptides with methyl iodide has been also described. The extract of seeds of Linum utitatissimum was analyzed directly by ESI-MS and neutral loss ESI-MS/MS technique. The analysis confirms the presence of cyclolinopeptides reported previously: CLA (c(Pro-Pro-Phe-Phe-Leu-Ile-Ile-Leu-Val), and CLB (c(Pro-Pro-Phe-Phe-Val-Ile-Met-Ile-Leu)). Cyclolinopeptides CLC, CLD, CLE, and CLG, which contain methionine oxide, were detected in relatively small quantities. These peptides results likely from the oxidation of their not reported precursors: CLD' (c (Pro- Phe-Phe-Trp-Ile-Met-Leu-Leu)), CLE'(c (Pro-Leu-Phe-Ile-Met-Leu-Val-Phe)), CLF (c (Pro-Phe-Phe-Trp- Val-Met-Leu-Met), and CLG (c (Pro-Phe-Phe-Trp-Ile-Met-Leu-Met), present at higher concentrations in the extract protected from atmospheric oxygen. The sequences of the unreported cyclic peptides were proposed on the basis of CID experiments and homology with peptides described by Morita,1,2 and supported by the fragmentation of synthetic analogues of CLA of a known structure.
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Affiliation(s)
- Piotr Stefanowicz
- Faculty of Chemistry, University of Wrocław, Joliot Curie 14, PL 50383 Wrocław, Poland.
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Liu Y, Liang F, Cui L, Xia M, Zhao L, Yang Y, Shi J, Abliz Z. Multi-stage mass spectrometry of furostanol saponins combined with electrospray ionization in positive and negative ion modes. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2004; 18:235-238. [PMID: 14745777 DOI: 10.1002/rcm.1310] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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Inai Y, Ousaka N, Okabe T. Mechanism for the noncovalent chiral domino effect: new paradigm for the chiral role of the N-terminal segment in a 3(10)-helix. J Am Chem Soc 2003; 125:8151-62. [PMID: 12837085 DOI: 10.1021/ja035040s] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Recently, novel chiral interactions on 3(10)-helical peptides, of which the helicity is controlled by external chiral stimulus operating on the N-terminus, were proposed as a "noncovalent chiral domino effect (NCDE)" (Inai, Y.; et al. J. Am. Chem. Soc. 2000, 122, 11731. Inai, Y.; et al. J. Am. Chem. Soc. 2002, 124, 2466). The present study clarifies the mechanism for generating the NCDE. For this purpose, achiral nonapeptide (1), H-beta-Ala-(Delta(Z)Phe-Aib)(4)-OMe [Delta(Z)Phe = (Z)-didehydrophenylalanine, Aib = alpha-aminoisobutyric acid], was synthesized. Peptide 1 alone adopts a 3(10)-helical conformation in chloroform. On the basis of the induced CD signals of peptide 1 with chiral additives, chiral acid enabling the predominant formation of a one-handed helix was shown to need at least both carboxyl and urethane groups; that is, Boc-l-amino acid (Boc = tert-butoxycarbonyl) strongly induces a right-handed helix. NMR studies (NH resonance variations, low-temperature measurement, and NOESY) were performed for a CDCl(3) solution of peptide 1 and chiral additive, supporting the view that the N-terminal H-beta-Ala-Delta(Z)Phe-Aib, including the two free amide NH's, captures effectively a Boc-amino acid molecule through three-point interactions. The H-beta-Ala's amino group binds to the carboxyl group to form a salt bridge, while the Aib(3) NH is hydrogen-bonded to either oxygen of the carboxylate group. Subsequently, the free Delta(Z)Phe(2) NH forms a hydrogen bond to the urethane carbonyl oxygen. A semiempirical molecular orbital computation explicitly demonstrated that the dynamic looping complexation is energetically permitted and that the N-terminal segment of a right-handed 3(10)-helix binds more favorably to a Boc-l-amino acid than to the corresponding d-species. In conclusion, the N-terminal segment of a 3(10)-helix, ubiquitous in natural proteins and peptides, possesses the potency of chiral recognition in the backbone itself, furthermore enabling the conversion of the terminally acquired chiral sign and power into a dynamic control of the original helicity and helical stability.
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Affiliation(s)
- Yoshihito Inai
- Department of Environmental Technology and Urban Planning, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan.
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de Visser PC, Kriek NMAJ, van Hooft PAV, Van Schepdael A, Filippov DV, van der Marel GA, Overkleeft HS, van Boom JH, Noort D. Solid-phase synthesis of polymyxin B1 and analogues via a safety-catch approach. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 2003; 61:298-306. [PMID: 12753377 DOI: 10.1034/j.1399-3011.2003.00061.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
As part of a program towards the development of novel antibiotics, a convenient method for solid-phase synthesis of the cyclic cationic peptide polymyxin B1 and analogues thereof is described. The methodology, based on cleavage-by-cyclization using Kenner's safety-catch linker, yields crude products with purities ranging from 37-67%. Antibacterial assays revealed that analogues 23-26, in which the (S)-6-methyloctanoic acid moiety is replaced with shorter acyl chains, exhibit distinct antimicrobial activity. The results suggest that the length of the acyl chain is rather critical for antimicrobial activity. On the other hand, substitution of the hydrophobic ring-segment D-Phe-6/Leu-7 in polymyxin B1 with dipeptide mimics (i.e. analogues 27-33) resulted in almost complete loss of antimicrobial activity.
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Affiliation(s)
- P C de Visser
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, PO Box 9402, 2300 RA Leiden, The Netherlands
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Govaerts C, Li C, Orwa J, Van Schepdael A, Adams E, Roets E, Hoogmartens J. Sequencing of bacitracin A and related minor components by liquid chromatography/electrospray ionization ion trap tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2003; 17:1366-1379. [PMID: 12811761 DOI: 10.1002/rcm.1058] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A selective reversed-phase liquid chromatography/mass spectrometry (LC/MS(n)) method is described for the characterization of related compounds in commercial bacitracin samples. Mass spectral data for these polypeptide antibiotics were acquired on a LCQ ion trap mass spectrometer equipped with an electrospray ionization probe operated in the positive and negative ion mode. The LCQ ion trap is ideally suited for the sequencing of those linear side-chain cyclized peptides because it provides on-line LC/MS(n) capability. Using this method bacitracin A, 1-epibacitracin A, bacitracins B(1), B(2), B(3) and bacitracin F were sequenced and previous sequencing was confirmed. Bacitracins C(1), C(2), C(3), D, H(2) and H(3) were resolved chromatographically and their ring portion was sequenced for the first time. Four components not described in the literature (1-epibacitracin B(1), 1-epibacitracin B(2), 1-epibacitracin C(1) and H(4)) were sequenced completely for the first time. The main advantage of this hyphenated LC/MS(n) technique is the characterization of the related substances without time-consuming isolation and purification procedures.
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Affiliation(s)
- Cindy Govaerts
- Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium
| | - Chunlan Li
- Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium
| | - Jennifer Orwa
- Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium
| | - Ann Van Schepdael
- Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium
| | - Erwin Adams
- Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium
| | - Eugène Roets
- Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium
| | - Jos Hoogmartens
- Katholieke Universiteit Leuven, Faculteit Farmaceutische Wetenschappen, Laboratorium voor Farmaceutische Chemie en Analyse van Geneesmiddelen, E. Van Evenstraat 4, B-3000 Leuven, Belgium
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2002; 37:652-661. [PMID: 12112749 DOI: 10.1002/jms.253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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