1
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Zhukrovska K, Binda E, Fedorenko V, Marinelli F, Yushchuk O. The Impact of Heterologous Regulatory Genes from Lipodepsipeptide Biosynthetic Gene Clusters on the Production of Teicoplanin and A40926. Antibiotics (Basel) 2024; 13:115. [PMID: 38391501 PMCID: PMC10886168 DOI: 10.3390/antibiotics13020115] [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: 12/26/2023] [Revised: 01/13/2024] [Accepted: 01/18/2024] [Indexed: 02/24/2024] Open
Abstract
StrR-like pathway-specific transcriptional regulators (PSRs) function as activators in the biosynthesis of various antibiotics, including glycopeptides (GPAs), aminoglycosides, aminocoumarins, and ramoplanin-like lipodepsipeptides (LDPs). In particular, the roles of StrR-like PSRs have been previously investigated in the biosynthesis of streptomycin, novobiocin, GPAs like balhimycin, teicoplanin, and A40926, as well as LDP enduracidin. In the current study, we focused on StrR-like PSRs from the ramoplanin biosynthetic gene cluster (BGC) in Actinoplanes ramoplaninifer ATCC 33076 (Ramo5) and the chersinamycin BGC in Micromonospora chersina DSM 44151 (Chers28). Through the analysis of the amino acid sequences of Ramo5 and Chers28, we discovered that these proteins are phylogenetically distant from other experimentally investigated StrR PSRs, although all StrR-like PSRs found in BGCs for different antibiotics share a conserved secondary structure. To investigate whether Ramo5 and Chers28, given their phylogenetic positions, might influence the biosynthesis of other antibiotic pathways governed by StrR-like PSRs, the corresponding genes (ramo5 and chers28) were heterologously expressed in Actinoplanes teichomyceticus NRRL B-16726 and Nonomuraea gerenzanensis ATCC 39727, which produce the clinically-relevant GPAs teicoplanin and A40926, respectively. Recombinant strains of NRRL B-16726 and ATCC 39727 expressing chers28 exhibited improved antibiotic production, although the expression of ramo5 did not yield the same effect. These results demonstrate that some StrR-like PSRs can "cross-talk" between distant biosynthetic pathways and might be utilized as tools for the activation of silent BGCs regulated by StrR-like PSRs.
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Affiliation(s)
- Kseniia Zhukrovska
- Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, 79005 Lviv, Ukraine
| | - Elisa Binda
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Victor Fedorenko
- Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, 79005 Lviv, Ukraine
| | - Flavia Marinelli
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
| | - Oleksandr Yushchuk
- Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, 79005 Lviv, Ukraine
- Department of Biotechnology and Life Sciences, University of Insubria, 21100 Varese, Italy
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2
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Yushchuk O, Binda E, Rückert-Reed C, Berini F, Fedorenko V, Kalinowski J, Marinelli F. Actinoplanes oblitus sp. nov., producing the glycopeptide antibiotic A477. Int J Syst Evol Microbiol 2024; 74. [PMID: 38190227 DOI: 10.1099/ijsem.0.006225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2024] Open
Abstract
In 1973, Eli Lilly and Company described the filamentous actinomycete producing the glycopeptide antibiotic A477 as an Actinoplanes species on the basis of its morphological and physiological features and deposited it as NRRL 3884T. In this paper, we report that the phylogenetic analysis based on the 16S rRNA gene sequence and the whole genome phylogenomic study indicate that NRRL 3884T forms a distinct monophyletic line within the genus Actinoplanes, being most closely related to Actinoplanes octamycinicus NBRC 14524T [99.6 % 16S rRNA gene similarity, 89.4 % average nucleotide identity (ANI), 46.0 % digital DNA-DNA hybridization (dDDH)] and Actinoplanes ianthinogenes NBRC 13996T (98.8 % 16S rRNA gene similarity, 89.0 % ANI, 47.0 % dDDH). NRRL 3884T forms an extensively branched, non-fragmented vegetative mycelium; either sterile aerial hyphae or regular subglobose sporangia are formed depending on cultivation conditions. The cell wall contains meso-2,6-diaminopimelic acid and 2,6-diamino-3-hydroxypimelic acid and the diagnostic sugars are glucose, mannose and ribose with a minor amount of rhamnose. The predominant menaquinone (MK) is MK-9(H4), with minor amounts of MK-9(H2), MK-9(H6) and MK-9(H8). Mycolic acids are absent. The diagnostic phospholipids are diphosphatidylglycerol and phosphatidylethanolamine. The major cellular fatty acids are anteiso-C17 : 0, iso-C16 : 0 and iso-C15 : 0, with moderate amounts of anteiso-C15 : 0 and iso-C17 : 0. The genomic G+C content is 71.5 mol%. Significant differences in the genomic, morphological, chemotaxonomic and biochemical data between NRRL 3884T and the two most closely related Actinoplanes type strains clearly demonstrate that NRRL 3884T represents a novel species of the genus Actinoplanes, for which the name Actinoplanes oblitus sp. nov. is proposed. The type strain is NRRL 3884T (=DSM 116196T).
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Affiliation(s)
- Oleksandr Yushchuk
- University of Insubria, Department of Biotechnology and Life Sciences, 21100 Varese, Italy
- Ivan Franko National University of Lviv, Department of Genetics and Biotechnology, 79005 Lviv, Ukraine
| | - Elisa Binda
- University of Insubria, Department of Biotechnology and Life Sciences, 21100 Varese, Italy
| | | | - Francesca Berini
- University of Insubria, Department of Biotechnology and Life Sciences, 21100 Varese, Italy
| | - Victor Fedorenko
- Ivan Franko National University of Lviv, Department of Genetics and Biotechnology, 79005 Lviv, Ukraine
| | - Jörn Kalinowski
- Bielefeld University, Technology Platform Genomics, CeBiTec, 33615 Bielefeld, Germany
| | - Flavia Marinelli
- University of Insubria, Department of Biotechnology and Life Sciences, 21100 Varese, Italy
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3
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Gestels Z, De Baetselier I, Abdellati S, Manoharan-Basil SS, Kenyon C. Ramoplanin as a novel therapy for Neisseria gonorrhoeae infection: an in vitro and in vivo study in Galleria mellonella. J Med Microbiol 2024; 73. [PMID: 38214499 DOI: 10.1099/jmm.0.001785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024] Open
Abstract
Neisseria gonorrhoeae is a bacterial pathogen that causes gonorrhoea, a sexually transmitted infection. Increasing antimicrobial resistance in N. gonorrhoeae is providing motivation to develop new treatment options. In this study, we investigated the effectiveness of the antibiotic ramoplanin as a treatment for N. gonorrhoeae infection. We tested the effectiveness of ramoplanin in vitro against 14 World Health Organization (WHO) reference strains of N. gonorrhoeae and found that it was active against all 14 strains tested. Furthermore, in a Galleria mellonella infection model of N. gonorrhoeae WHO P, we demonstrated that ramoplanin was active in vivo without any evidence of toxicity. This suggests that ramoplanin might be a new promising antibiotic treatment for gonorrhoea.
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Affiliation(s)
- Zina Gestels
- STI Unit, Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp 2000, Belgium
| | - Irith De Baetselier
- Clinical and Reference Laboratory, Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium
| | - Said Abdellati
- Clinical and Reference Laboratory, Department of Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium
| | | | - Chris Kenyon
- STI Unit, Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp 2000, Belgium
- Division of Infectious Diseases and HIV Medicine, University of Cape Town, Cape Town 7700, South Africa
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4
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Marschall E, Cass RW, Prasad KM, Swarbrick JD, McKay AI, Payne JAE, Cryle MJ, Tailhades J. Synthetic ramoplanin analogues are accessible by effective incorporation of arylglycines in solid-phase peptide synthesis. Chem Sci 2023; 15:195-203. [PMID: 38131086 PMCID: PMC10732013 DOI: 10.1039/d3sc01944f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 09/09/2023] [Indexed: 12/23/2023] Open
Abstract
The threat of antimicrobial resistance to antibiotics requires a continual effort to develop alternative treatments. Arylglycines (or phenylglycines) are one of the signature amino acids found in many natural peptide antibiotics, but their propensity for epimerization in solid-phase peptide synthesis (SPPS) has prevented their use in long peptide sequences. We have now identified an optimized protocol that allows the synthesis of challenging non-ribosomal peptides including precursors of the glycopeptide antibiotics and an analogue of feglymycin (1 analogue, 20%). We have exploited this protocol to synthesize analogues of the peptide antibiotic ramoplanin using native chemical ligation/desulfurization (1 analogue, 6.5%) and head-to-tail macrocyclization in excellent yield (6 analogues, 3-9%), with these compounds extensively characterized by NMR (U-shaped structure) and antimicrobial activity assays (two clinical isolates). This method significantly reduces synthesis time (6-9 days) when compared with total syntheses (2-3 months) and enables drug discovery programs to include arylglycines in structure-activity relationship studies and drug development.
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Affiliation(s)
- Edward Marschall
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Rachel W Cass
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Komal M Prasad
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - James D Swarbrick
- Department of Microbiology, Monash University Clayton VIC 3800 Australia
| | - Alasdair I McKay
- Department of Chemistry, Monash University Clayton VIC 3800 Australia
| | - Jennifer A E Payne
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Max J Cryle
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Julien Tailhades
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
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5
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Parra J, Beaton A, Seipke RF, Wilkinson B, Hutchings MI, Duncan KR. Antibiotics from rare actinomycetes, beyond the genus Streptomyces. Curr Opin Microbiol 2023; 76:102385. [PMID: 37804816 DOI: 10.1016/j.mib.2023.102385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 09/05/2023] [Accepted: 09/06/2023] [Indexed: 10/09/2023]
Abstract
Throughout the golden age of antibiotic discovery, Streptomyces have been unsurpassed for their ability to produce bioactive metabolites. Yet, this success has been hampered by rediscovery. As we enter a new stage of biodiscovery, omics data and existing scientific repositories can enable informed choices on the biodiversity that may yield novel antibiotics. Here, we focus on the chemical potential of rare actinomycetes, defined as bacteria within the order Actinomycetales, but not belonging to the genus Streptomyces. They are named as such due to their less-frequent isolation under standard laboratory practices, yet there is increasing evidence to suggest these biologically diverse genera harbour considerable biosynthetic and chemical diversity. In this review, we focus on examples of successful isolation and genera that have been the focus of more concentrated biodiscovery efforts, we survey the representation of rare actinomycete taxa, compared with Streptomyces, across natural product data repositories in addition to its biosynthetic potential. This is followed by an overview of clinically useful drugs produced by rare actinomycetes and considerations for future biodiscovery efforts. There is much to learn about these underexplored taxa, and mounting evidence suggests that they are a fruitful avenue for the discovery of novel antimicrobials.
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Affiliation(s)
- Jonathan Parra
- Instituto de Investigaciones Farmacéuticas (INIFAR), Facultad de Farmacia, Universidad de Costa Rica, San José 11501-2060, Costa Rica; Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, San José 1174-1200, Costa Rica
| | - Ainsley Beaton
- John Innes Centre, Department of Molecular Microbiology, Norwich Research Park, Norwich NR4 7UH, UK
| | - Ryan F Seipke
- University of Leeds, Faculty of Biological Sciences, Astbury Centre for Structural Molecular Biology, Leeds LS2 9JT, UK
| | - Barrie Wilkinson
- John Innes Centre, Department of Molecular Microbiology, Norwich Research Park, Norwich NR4 7UH, UK
| | - Matthew I Hutchings
- John Innes Centre, Department of Molecular Microbiology, Norwich Research Park, Norwich NR4 7UH, UK
| | - Katherine R Duncan
- University of Strathclyde, Strathclyde Institute of Pharmacy and Biomedical Sciences, 141 Cathedral Street, Glasgow G4 0RE, UK.
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6
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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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7
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Alshrari AS, Hudu SA, Elmigdadi F, Imran M. The Urgent Threat of Clostridioides difficile Infection: A Glimpse of the Drugs of the Future, with Related Patents and Prospects. Biomedicines 2023; 11:biomedicines11020426. [PMID: 36830964 PMCID: PMC9953237 DOI: 10.3390/biomedicines11020426] [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: 01/05/2023] [Revised: 01/25/2023] [Accepted: 01/26/2023] [Indexed: 02/05/2023] Open
Abstract
Clostridioides difficile infection (CDI) is an urgent threat and unmet medical need. The current treatments for CDI are not enough to fight the burden of CDI and recurrent CDI (r-CDI). This review aims to highlight the future drugs for CDI and their related patented applications. The non-patent literature was collected from PubMed and various authentic websites of pharmaceutical industries. The patent literature was collected from free patent databases. Many possible drugs of the future for CDI, with diverse mechanisms of action, are in development in the form of microbiota-modulating agents (e.g., ADS024, CP101, RBX2660, RBX7455, SYN-004, SER-109, VE303, DAV132, MET-2, and BB128), small molecules (e.g., ridinilazole, ibezapolstat, CRS3123, DNV3837, MGB-BP-3, alanyl-L-glutamine, and TNP-2198), antibodies (e.g., IM-01 and LMN-201), and non-toxic strains of CD (e.g., NTCD-M3). The development of some therapeutic agents (e.g., DS-2969b, OPS-2071, cadazolid, misoprostol, ramoplanin, KB109, LFF571, and Ramizol) stopped due to failed clinical trials or unknown reasons. The patent literature reveals some important inventions for the existing treatments of CDI and supports the possibility of developing more and better CDI-treatment-based inventions, including patient-compliant dosage forms, targeted drug delivery, drug combinations of anti-CDI drugs possessing diverse mechanisms of action, probiotic and enzymatic supplements, and vaccines. The current pipeline of anti-CDI medications appears promising. However, it will be fascinating to see how many of the cited are successful in gaining approval from drug regulators such as the US FDA and becoming medicines for CDI and r-CDI.
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Affiliation(s)
- Ahmed S. Alshrari
- Department of Medical Laboratory Technology, College of Applied Medical Sciences, Northern Border University, Arar 91431, Saudi Arabia
| | - Shuaibu Abdullahi Hudu
- Department of Basic Medical and Dental Sciences, Faculty of Dentistry, Zarqa University, Zarqa 13110, Jordan
- Correspondence: (S.A.H.); (M.I.)
| | - Fayig Elmigdadi
- Department of Basic Medical and Dental Sciences, Faculty of Dentistry, Zarqa University, Zarqa 13110, Jordan
| | - Mohd. Imran
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Northern Border University, Rafha 91911, Saudi Arabia
- Correspondence: (S.A.H.); (M.I.)
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8
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Gribble GW. Naturally Occurring Organohalogen Compounds-A Comprehensive Review. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2023; 121:1-546. [PMID: 37488466 DOI: 10.1007/978-3-031-26629-4_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
The present volume is the third in a trilogy that documents naturally occurring organohalogen compounds, bringing the total number-from fewer than 25 in 1968-to approximately 8000 compounds to date. Nearly all of these natural products contain chlorine or bromine, with a few containing iodine and, fewer still, fluorine. Produced by ubiquitous marine (algae, sponges, corals, bryozoa, nudibranchs, fungi, bacteria) and terrestrial organisms (plants, fungi, bacteria, insects, higher animals) and universal abiotic processes (volcanos, forest fires, geothermal events), organohalogens pervade the global ecosystem. Newly identified extraterrestrial sources are also documented. In addition to chemical structures, biological activity, biohalogenation, biodegradation, natural function, and future outlook are presented.
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Affiliation(s)
- Gordon W Gribble
- Department of Chemistry, Dartmouth College, Hanover, NH, 03755, USA.
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9
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Wang X, Wu K, Zhang H, Liu J, Yang Z, Bai J, Liu H, Shao L. Efficient side-chain deacylation of polymyxin B1 in recombinant Streptomyces strains. Biotechnol Lett 2022; 44:1287-1299. [PMID: 36076042 DOI: 10.1007/s10529-022-03290-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 08/04/2022] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Polymyxins are antibacterial polypeptides used as "last resort" therapy option for multidrug-resistant Gram-negative bacteria. The expansion of polymyxin-resistant infections has inspired development of novel polymyxin derivatives, and deacylation is one of the critical steps in generating those antibiotics. Deacylase from Actinoplanes utahensis hydrolyze the acyl moieties of echinocandins, and also efficiently deacylates daptomycin, ramoplanin and other important antibiotics. Here, deacylase was studied considering its potential usefulness in deacylating polymyxin B1. RESULTS All the six recombinant strains containing the deacylase gene catalyzed hydrolysis of polymyxin B1, yielding cyclic heptapeptides. The efficiency of recombinant S. albus (SAL701) was higher than that of the others, and deacylation was the most efficient at 40 °C in 0.2 M Tris buffer (pH 8.0) with 0.2 M Mg2+. The optimal substrate concentration of SAL701 was increased from 2.0 to 6.0 g/L. SAL701 was highly thermostable, showing no loss of activity at 50 °C for 12 h, and the mycelia could be recycled at least three times without loss of catalytic activity. SAL701 could not deacylate β-lactam substrate such as penicillin G and cephalosporin C. Deacylase catalyzes the amide bond 1 closest to the nucleus of polymyxin B1 rather than the other bond, suggesting that it has high catalytic site specificity. Homology modeling and the docking results implied that Thr190 in deacylase could facilitate hydrolysis with high regioselectivity. CONCLUSIONS These results show that SAL701 is effective in increasing the cyclic heptapeptide moiety of polymyxin B1. These properties of the biocatalyst may enable its development in the industrial production of polymyxins antibiotics.
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Affiliation(s)
- Xiaojing Wang
- Affiliated Zhoupu Hospital, Shanghai University of Medicine and Health Sciences, Shanghai, China.,Microbial Pharmacology Laboratory, Shanghai University of Medicine and Health Sciences, Shanghai, China.,School of Pharmacy, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Kai Wu
- Microbial Pharmacology Laboratory, Shanghai University of Medicine and Health Sciences, Shanghai, China.,School of Pharmacy, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Hanzhi Zhang
- Abiochem Biotechnology Co., Ltd, Shanghai, China
| | - Jing Liu
- Microbial Pharmacology Laboratory, Shanghai University of Medicine and Health Sciences, Shanghai, China.,School of Medical Technology, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Zhijun Yang
- Microbial Pharmacology Laboratory, Shanghai University of Medicine and Health Sciences, Shanghai, China.,School of Pharmacy, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Jing Bai
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, China
| | - Hao Liu
- Department of Antibiotics and Microorganisms, Shanghai Institute for Food and Drug Control, Shanghai, China.
| | - Lei Shao
- Microbial Pharmacology Laboratory, Shanghai University of Medicine and Health Sciences, Shanghai, China. .,School of Pharmacy, Shanghai University of Medicine and Health Sciences, Shanghai, China.
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10
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Nonribosomal Peptide Synthesis Definitely Working Out of the Rules. Microorganisms 2022; 10:microorganisms10030577. [PMID: 35336152 PMCID: PMC8949500 DOI: 10.3390/microorganisms10030577] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/02/2022] [Accepted: 03/03/2022] [Indexed: 12/04/2022] Open
Abstract
Nonribosomal peptides are microbial secondary metabolites exhibiting a tremendous structural diversity and a broad range of biological activities useful in the medical and agro-ecological fields. They are built up by huge multimodular enzymes called nonribosomal peptide synthetases. These synthetases are organized in modules constituted of adenylation, thiolation, and condensation core domains. As such, each module governs, according to the collinearity rule, the incorporation of a monomer within the growing peptide. The release of the peptide from the assembly chain is finally performed by a terminal core thioesterase domain. Secondary domains with modifying catalytic activities such as epimerization or methylation are sometimes included in the assembly lines as supplementary domains. This assembly line structure is analyzed by bioinformatics tools to predict the sequence and structure of the final peptides according to the sequence of the corresponding synthetases. However, a constantly expanding literature unravels new examples of nonribosomal synthetases exhibiting very rare domains and noncanonical organizations of domains and modules, leading to several amazing strategies developed by microorganisms to synthesize nonribosomal peptides. In this review, through several examples, we aim at highlighting these noncanonical pathways in order for the readers to perceive their complexity.
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11
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12
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Gene editing enables rapid engineering of complex antibiotic assembly lines. Nat Commun 2021; 12:6872. [PMID: 34824225 PMCID: PMC8616955 DOI: 10.1038/s41467-021-27139-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/02/2021] [Indexed: 11/08/2022] Open
Abstract
Re-engineering biosynthetic assembly lines, including nonribosomal peptide synthetases (NRPS) and related megasynthase enzymes, is a powerful route to new antibiotics and other bioactive natural products that are too complex for chemical synthesis. However, engineering megasynthases is very challenging using current methods. Here, we describe how CRISPR-Cas9 gene editing can be exploited to rapidly engineer one of the most complex megasynthase assembly lines in nature, the 2.0 MDa NRPS enzymes that deliver the lipopeptide antibiotic enduracidin. Gene editing was used to exchange subdomains within the NRPS, altering substrate selectivity, leading to ten new lipopeptide variants in good yields. In contrast, attempts to engineer the same NRPS using a conventional homologous recombination-mediated gene knockout and complementation approach resulted in only traces of new enduracidin variants. In addition to exchanging subdomains within the enduracidin NRPS, subdomains from a range of NRPS enzymes of diverse bacterial origins were also successfully utilized.
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13
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Kullar R, Tran MCN, Goldstein EJC. Investigational Treatment Agents for Recurrent Clostridioides difficile Infection (rCDI). J Exp Pharmacol 2020; 12:371-384. [PMID: 33116952 PMCID: PMC7553590 DOI: 10.2147/jep.s242959] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 08/13/2020] [Indexed: 11/23/2022] Open
Abstract
Clostridioides difficile infection (CDI) is a major cause of nosocomial diarrhea that is deemed a global health threat. C. difficile strain BI/NAP1/027 has contributed to the increase in the mortality, severity of CDI outbreaks and recurrence rates (rCDI). Updated CDI treatment guidelines suggest vancomycin and fidaxomicin as initial first-line therapies that have initial clinical cure rates of over 80%. Unacceptably high recurrence rates of 15–30% in patients for the first episode and 40% for the second recurrent episode are reported. Alternative treatments for rCDI include fecal microbiota transplant and a human monoclonal antibody, bezlotoxumab, that can be used in patients with high risk of rCDI. Various emerging potential therapies with narrow spectrum of activity and little systemic absorption that are in development include 1) Ibezapolstat (formerly ACX-362E), MGB-BP-3, and DS-2969b-targeting bacterial DNA replication, 2) CRS3213 (REP3123)-inhibiting toxin production and spore formation, 3) ramizol and ramoplanin-affecting bacterial cell wall, 4) LFF-571-blocking protein synthesis, 5) Alanyl-L-Glutamine (alanylglutamine)-inhibiting damage caused by C. difficile by protecting intestinal mucosa, and 6) DNV3837 (MCB3681)-prodrug consisting of an oxazolidinone–quinolone combination that converts to the active form DNV3681 that has activity in vitro against C. difficile. This review article provides an overview of these developing drugs that can have potential role in the treatment of rCDI and in lowering recurrence rates.
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Affiliation(s)
| | - Mai-Chi N Tran
- Pharmacy Department, Keck Medical Center of USC, Los Angeles, CA, USA.,Clinica Juan Pablo Medical Group, Los Angeles, CA, USA
| | - Ellie J C Goldstein
- R.M. Alden Research Laboratory, Santa Monica, CA, USA.,David Geffen School of Medicine, Los Angeles, CA, USA
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14
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Morgan KT, Zheng J, McCafferty DG. Discovery of Six Ramoplanin Family Gene Clusters and the Lipoglycodepsipeptide Chersinamycin*. Chembiochem 2020; 22:176-185. [PMID: 32805078 DOI: 10.1002/cbic.202000555] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Indexed: 11/10/2022]
Abstract
Ramoplanins and enduracidins are peptidoglycan lipid intermediate II-binding lipodepsipeptides with broad-spectrum activity against methicillin- and vancomycin-resistant Gram-positive pathogens. Targeted genome mining using probes from conserved sequences within the ramoplanin/enduracidin biosynthetic gene clusters (BGCs) was used to identify six microorganisms with BGCs predicted to produce unique lipodepsipeptide congeners of ramoplanin and enduracidin. Fermentation of Micromonospora chersina yielded a novel lipoglycodepsipeptide, called chersinamycin, which exhibited good antibiotic activity against Gram-positive bacteria (1-2 μg/mL) similar to the ramoplanins and enduracidins. The covalent structure of chersinamycin was determined by NMR spectroscopy and tandem mass spectrometry in conjunction with chemical degradation studies. These six new BGCs and isolation of a new antimicrobial peptide provide much-needed tools to investigate the fundamental aspects of lipodepsipeptide biosynthesis and to facilitate efforts to produce novel antibiotics capable of combating antibiotic-resistant infections.
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Affiliation(s)
- Kelsey T Morgan
- Department of Chemistry, Duke University, Durham, NC 27708, USA
| | - Jeffrey Zheng
- Department of Chemistry, Duke University, Durham, NC 27708, USA
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15
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Mitachi K, Yun HG, Gillman CD, Skorupinska-Tudek K, Swiezewska E, Clemons WM, Kurosu M. Substrate Tolerance of Bacterial Glycosyltransferase MurG: Novel Fluorescence-Based Assays. ACS Infect Dis 2020; 6:1501-1516. [PMID: 31769280 DOI: 10.1021/acsinfecdis.9b00242] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
MurG (uridine diphosphate-N-acetylglucosamine/N-acetylmuramyl-(pentapeptide) pyrophosphoryl-undecaprenol N-acetylglucosamine transferase) is an essential bacterial glycosyltransferase that catalyzes the N-acetylglucosamine (GlcNAc) transformation of lipid I to lipid II during peptidoglycan biosynthesis. Park's nucleotide has been a convenient biochemical tool to study the function of MraY (phospho-MurNAc-(pentapeptide) translocase) and MurG; however, no fluorescent probe has been developed to differentiate individual processes in the biotransformation of Park's nucleotide to lipid II via lipid I. Herein, we report a robust assay of MurG using either the membrane fraction of a M. smegmatis strain or a thermostable MraY and MurG of Hydrogenivirga sp. as enzyme sources, along with Park's nucleotide or Park's nucleotide-Nε-C6-dansylthiourea and uridine diphosphate (UDP)-GlcN-C6-FITC as acceptor and donor substrates. Identification of both the MraY and MurG products can be performed simultaneously by HPLC in dual UV mode. Conveniently, the generated lipid II fluorescent analogue can also be quantitated via UV-Vis spectrometry without the separation of the unreacted lipid I derivative. The microplate-based assay reported here is amenable to high-throughput MurG screening. A preliminary screening of a collection of small molecules has demonstrated the robustness of the assays and resulted in rediscovery of ristocetin A as a strong antimycobacterial MurG and MraY inhibitor.
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Affiliation(s)
- Katsuhiko Mitachi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, Tennessee 38163, United States
| | - Hyun Gi Yun
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, United States
| | - Cody D. Gillman
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, United States
| | - Karolina Skorupinska-Tudek
- Department of Lipid Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warszawa, Poland
| | - Ewa Swiezewska
- Department of Lipid Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warszawa, Poland
| | - William M. Clemons
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, California 91125, United States
| | - Michio Kurosu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, 881 Madison Avenue, Memphis, Tennessee 38163, United States
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16
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Semi-rational mutagenesis of an industrial Streptomyces fungicidicus strain for improved enduracidin productivity. Appl Microbiol Biotechnol 2020; 104:3459-3471. [DOI: 10.1007/s00253-020-10488-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/14/2020] [Accepted: 02/18/2020] [Indexed: 12/21/2022]
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17
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Yeh HW, Lin KH, Lyu SY, Li YS, Huang CM, Wang YL, Shih HW, Hsu NS, Wu CJ, Li TL. Biochemical and structural explorations of α-hydroxyacid oxidases reveal a four-electron oxidative decarboxylation reaction. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2019; 75:733-742. [PMID: 31373572 PMCID: PMC6677016 DOI: 10.1107/s2059798319009574] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 07/03/2019] [Indexed: 11/05/2022]
Abstract
Structural and enzymological explorations of α-hydroxyacid oxidases uncover new flavin mononucleotide-mediated reactions and intermediates. p-Hydroxymandelate oxidase (Hmo) is a flavin mononucleotide (FMN)-dependent enzyme that oxidizes mandelate to benzoylformate. How the FMN-dependent oxidation is executed by Hmo remains unclear at the molecular level. A continuum of snapshots from crystal structures of Hmo and its mutants in complex with physiological/nonphysiological substrates, products and inhibitors provides a rationale for its substrate enantioselectivity/promiscuity, its active-site geometry/reactivity and its direct hydride-transfer mechanism. A single mutant, Y128F, that extends the two-electron oxidation reaction to a four-electron oxidative decarboxylation reaction was unexpectedly observed. Biochemical and structural approaches, including biochemistry, kinetics, stable isotope labeling and X-ray crystallography, were exploited to reach these conclusions and provide additional insights.
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Affiliation(s)
- Hsien Wei Yeh
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Kuan Hung Lin
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Syue Yi Lyu
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Yi Shan Li
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Chun Man Huang
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Yung Lin Wang
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Hao Wei Shih
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Ning Shian Hsu
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Chang Jer Wu
- Department of Food Science, National Taiwan Ocean University, Keelung 202, Taiwan
| | - Tsung Lin Li
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
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18
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Wu C, Shang Z, Lemetre C, Ternei MA, Brady SF. Cadasides, Calcium-Dependent Acidic Lipopeptides from the Soil Metagenome That Are Active against Multidrug-Resistant Bacteria. J Am Chem Soc 2019; 141:3910-3919. [PMID: 30735616 PMCID: PMC6592427 DOI: 10.1021/jacs.8b12087] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The growing threat of antibiotic resistance necessitates the discovery of antibiotics that are active against resistant pathogens. Calcium-dependent antibiotics are a small family of structurally diverse acidic lipopeptides assembled by nonribosomal peptide synthetases (NRPSs) that are known to display various modes of action against antibiotic-resistant pathogens. Here we use NRPS adenylation (AD) domain sequencing to guide the identification, recovery, and cloning of the cde biosynthetic gene cluster from a soil metagenome. Heterologous expression of the cde biosynthetic gene cluster led to the production of cadasides A (1) and B (2), a subfamily of acidic lipopeptides that is distinct from previously characterized calcium-dependent antibiotics in terms of both overall structure and acidic residue rich peptide core. The cadasides inhibit the growth of multidrug-resistant Gram-positive pathogens by disrupting cell wall biosynthesis in the presence of high concentrations of calcium. Interestingly, sequencing of AD domains from diverse soils revealed that sequences predicted to arise from cadaside-like gene clusters are predominantly found in soils containing high levels of calcium carbonate.
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Affiliation(s)
| | | | - Christophe Lemetre
- Laboratory of Genetically Encoded Small Molecules, The Rockefeller University, New York, NY 10065
| | - Melinda A. Ternei
- Laboratory of Genetically Encoded Small Molecules, The Rockefeller University, New York, NY 10065
| | - Sean F. Brady
- Laboratory of Genetically Encoded Small Molecules, The Rockefeller University, New York, NY 10065
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19
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Tran MCN, Kullar R, Goldstein EJC. Investigational drug therapies currently in early-stage clinical development for the treatment of clostridioides (clostridium) difficile infection. Expert Opin Investig Drugs 2019; 28:323-335. [DOI: 10.1080/13543784.2019.1581763] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Mai-Chi N. Tran
- Department of Pharmacy, Providence St. John’s Health Center, Santa Monica,
CA, USA
- Department of Pharmacy, Clinica Juan Pablo Medical Group, Los Angeles,
CA, USA
| | | | - Ellie J. C. Goldstein
- R M Alden Research Laboratory, Santa Monica,
CA, USA
- David Geffen School of Medicine, Los Angeles,
CA, USA
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20
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Nagendra Prasad HS, Karthik CS, Manukumar HM, Mallesha L, Mallu P. New approach to address antibiotic resistance: Miss loading of functional membrane microdomains (FMM) of methicillin-resistant Staphylococcus aureus (MRSA). Microb Pathog 2018; 127:106-115. [PMID: 30503959 DOI: 10.1016/j.micpath.2018.11.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/22/2018] [Accepted: 11/26/2018] [Indexed: 12/13/2022]
Abstract
The synthesized potent piperazine analog ChDiPiCa was characterised by various spectroscopic techniques and for the first time evaluated functional membrane microdomain (FMM) disassembly in methicillin-resistant Staphylococcus aureus (MRSA). The ChDiPiCa showed excellent in vitro biocidal activity against MRSA at 26 μg/mL compared to the antibiotic streptomycin and bacitracin 14 μg/mL and 13 μg/mL at 10 μg concentration respectively. The membrane damaging property was confirmed by the SEM analysis. Further, we addressed the new approach for the first time to overcome antibiotic resistance of MRSA through membrane microdomain miss loading to lipids. By which, the ChDiPiCa confirms the significant activity in miss loading of FMM of MRSA which is validated by the fatty acid profile and lipid analysis. The result shows that, altered saturated (Lauric acid and Myristic acid), mono unsaturated (Oleic acid), and poly unsaturated (Linoleic acid and Linolenic acid) fatty acids and hypothesises, altered the membrane functional lipids. For the better understanding of miss loading of FMM by the ChDiPiCa, the in-silico molecular docking studies was analyzed and confirmed the predicted role. This suggests the way to develop ChDiPiCa in medicinal chemistry as anti-MRSA candidates and also this report opens up new window to treat microbial pathogens and infections.
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Affiliation(s)
- H S Nagendra Prasad
- Department of Chemistry, Sri Jayachamarajendra College of Engineering, JSS Science and Technology University, Mysuru, 570 006, Karnataka, India
| | - C S Karthik
- Department of Chemistry, Sri Jayachamarajendra College of Engineering, JSS Science and Technology University, Mysuru, 570 006, Karnataka, India
| | - H M Manukumar
- Department of Chemistry, Sri Jayachamarajendra College of Engineering, JSS Science and Technology University, Mysuru, 570 006, Karnataka, India
| | - L Mallesha
- PG Department of Chemistry, JSS College of Arts, Commerce and Science, Mysuru, 570025, Karnataka, India
| | - P Mallu
- Department of Chemistry, Sri Jayachamarajendra College of Engineering, JSS Science and Technology University, Mysuru, 570 006, Karnataka, India.
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21
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Komor AJ, Jasniewski AJ, Que L, Lipscomb JD. Diiron monooxygenases in natural product biosynthesis. Nat Prod Rep 2018; 35:646-659. [PMID: 29552683 PMCID: PMC6051903 DOI: 10.1039/c7np00061h] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Covering: up to 2017 The participation of non-heme dinuclear iron cluster-containing monooxygenases in natural product biosynthetic pathways has been recognized only recently. At present, two families have been discovered. The archetypal member of the first family, CmlA, catalyzes β-hydroxylation of l-p-aminophenylalanine (l-PAPA) covalently linked to the nonribosomal peptide synthetase (NRPS) CmlP, thereby effecting the first step in the biosynthesis of chloramphenicol by Streptomyces venezuelae. CmlA houses the diiron cluster in a metallo-β-lactamase protein fold instead of the 4-helix bundle fold of nearly every other diiron monooxygenase. CmlA couples O2 activation and substrate hydroxylation via a structural change caused by formation of the l-PAPA-loaded CmlP:CmlA complex. The other new diiron family is typified by two enzymes, AurF and CmlI, which catalyze conversion of aryl-amine substrates to aryl-nitro products with incorporation of oxygen from O2. AurF from Streptomyces thioluteus catalyzes the formation of p-nitrobenzoate from p-aminobenzoate as a precursor to the biostatic compound aureothin, whereas CmlI from S. venezuelae catalyzes the ultimate aryl-amine to aryl-nitro step in chloramphenicol biosynthesis. Both enzymes stabilize a novel type of peroxo-intermediate as the reactive species. The rare 6-electron N-oxygenation reactions of CmlI and AurF involve two progressively oxidized pathway intermediates. The enzymes optimize efficiency by utilizing one of the reaction pathway intermediates as an in situ reductant for the diiron cluster, while simultaneously generating the next pathway intermediate. For CmlI, this reduction allows mid-pathway regeneration of the peroxo intermediate required to complete the biosynthesis. CmlI ensures specificity by carrying out the multistep aryl-amine oxygenation without dissociating intermediate products.
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Affiliation(s)
- Anna J Komor
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
| | - Andrew J Jasniewski
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
| | - Lawrence Que
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
| | - John D Lipscomb
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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22
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Müller A, Klöckner A, Schneider T. Targeting a cell wall biosynthesis hot spot. Nat Prod Rep 2017; 34:909-932. [PMID: 28675405 DOI: 10.1039/c7np00012j] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Covering: up to 2017History points to the bacterial cell wall biosynthetic network as a very effective target for antibiotic intervention, and numerous natural product inhibitors have been discovered. In addition to the inhibition of enzymes involved in the multistep synthesis of the macromolecular layer, in particular, interference with membrane-bound substrates and intermediates essential for the biosynthetic reactions has proven a valuable antibacterial strategy. A prominent target within the peptidoglycan biosynthetic pathway is lipid II, which represents a particular "Achilles' heel" for antibiotic attack, as it is readily accessible on the outside of the cytoplasmic membrane. Lipid II is a unique non-protein target that is one of the structurally most conserved molecules in bacterial cells. Notably, lipid II is more than just a target molecule, since sequestration of the cell wall precursor may be combined with additional antibiotic activities, such as the disruption of membrane integrity or disintegration of membrane-bound multi-enzyme machineries. Within the membrane bilayer lipid II is likely organized in specific anionic phospholipid patches that form a particular "landing platform" for antibiotics. Nature has invented a variety of different "lipid II binders" of at least 5 chemical classes, and their antibiotic activities can vary substantially depending on the compounds' physicochemical properties, such as amphiphilicity and charge, and thus trigger diverse cellular effects that are decisive for antibiotic activity.
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Affiliation(s)
- Anna Müller
- Institute of Pharmaceutical Microbiology, University of Bonn, Bonn, Germany.
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23
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Min KR, Galvis A, Williams B, Rayala R, Cudic P, Ajdic D. Antibacterial and Antibiofilm Activities of a Novel Synthetic Cyclic Lipopeptide against Cariogenic Streptococcus mutans UA159. Antimicrob Agents Chemother 2017; 61:e00776-17. [PMID: 28533236 PMCID: PMC5527655 DOI: 10.1128/aac.00776-17] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 05/13/2017] [Indexed: 02/02/2023] Open
Abstract
Despite continuous efforts to control cariogenic dental biofilms, very few effective antimicrobial treatments exist. In this study, we characterized the activity of the novel synthetic cyclic lipopeptide 4 (CLP-4), derived from fusaricidin, against the cariogenic pathogen Streptococcus mutans UA159. We determined CLP-4's MIC, minimum bactericidal concentration (MBC), and spontaneous resistance frequency, and we performed time-kill assays. Additionally, we assessed CLP-4's potential to inhibit biofilm formation and eradicate preformed biofilms. Our results demonstrate that CLP-4 has strong antibacterial activity in vitro and is a potent bactericidal agent with low spontaneous resistance frequency. At a low concentration of 5 μg/ml, CLP-4 completely inhibited S. mutans UA159 biofilm formation, and at 50 μg/ml, it reduced the viability of established biofilms by >99.99%. We also assessed CLP-4's cytotoxicity and stability against proteolytic digestion. CLP-4 withstood trypsin or chymotrypsin digestion even after treatment for 24 h, and our toxicity studies showed that CLP-4 effective concentrations had negligible effects on hemolysis and the viability of human oral fibroblasts. In summary, our findings showed that CLP-4 is a potent antibacterial and antibiofilm agent with remarkable stability and low nonspecific cytotoxicity. Hence, CLP-4 is a promising novel antimicrobial peptide with potential for clinical application in the prevention and treatment of dental caries.
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Affiliation(s)
- Kyung R Min
- Department of Dermatology and Cutaneous Surgery, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Adriana Galvis
- Department of Dermatology and Cutaneous Surgery, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Brandon Williams
- Department of Chemistry and Biochemistry, Center for Molecular Biology and Biotechnology, Florida Atlantic University, Jupiter, Florida, USA
| | - Ramanjaneyulu Rayala
- Department of Chemistry and Biochemistry, Center for Molecular Biology and Biotechnology, Florida Atlantic University, Jupiter, Florida, USA
| | - Predrag Cudic
- Department of Chemistry and Biochemistry, Center for Molecular Biology and Biotechnology, Florida Atlantic University, Jupiter, Florida, USA
| | - Dragana Ajdic
- Department of Dermatology and Cutaneous Surgery, Miller School of Medicine, University of Miami, Miami, Florida, USA
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24
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Agarwal V, Miles ZD, Winter JM, Eustáquio AS, El Gamal AA, Moore BS. Enzymatic Halogenation and Dehalogenation Reactions: Pervasive and Mechanistically Diverse. Chem Rev 2017; 117:5619-5674. [PMID: 28106994 PMCID: PMC5575885 DOI: 10.1021/acs.chemrev.6b00571] [Citation(s) in RCA: 246] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Naturally produced halogenated compounds are ubiquitous across all domains of life where they perform a multitude of biological functions and adopt a diversity of chemical structures. Accordingly, a diverse collection of enzyme catalysts to install and remove halogens from organic scaffolds has evolved in nature. Accounting for the different chemical properties of the four halogen atoms (fluorine, chlorine, bromine, and iodine) and the diversity and chemical reactivity of their organic substrates, enzymes performing biosynthetic and degradative halogenation chemistry utilize numerous mechanistic strategies involving oxidation, reduction, and substitution. Biosynthetic halogenation reactions range from simple aromatic substitutions to stereoselective C-H functionalizations on remote carbon centers and can initiate the formation of simple to complex ring structures. Dehalogenating enzymes, on the other hand, are best known for removing halogen atoms from man-made organohalogens, yet also function naturally, albeit rarely, in metabolic pathways. This review details the scope and mechanism of nature's halogenation and dehalogenation enzymatic strategies, highlights gaps in our understanding, and posits where new advances in the field might arise in the near future.
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Affiliation(s)
- Vinayak Agarwal
- Center for Oceans and Human Health, Scripps Institution of Oceanography, University of California, San Diego
| | - Zachary D. Miles
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego
| | | | - Alessandra S. Eustáquio
- College of Pharmacy, Department of Medicinal Chemistry & Pharmacognosy and Center for Biomolecular Sciences, University of Illinois at Chicago
| | - Abrahim A. El Gamal
- Center for Oceans and Human Health, Scripps Institution of Oceanography, University of California, San Diego
| | - Bradley S. Moore
- Center for Oceans and Human Health, Scripps Institution of Oceanography, University of California, San Diego
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego
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25
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Jadhav KB, Stein C, Makarewicz O, Pradel G, Lichtenecker RJ, Sack H, Heinemann SH, Arndt HD. Bioactivity of topologically confined gramicidin A dimers. Bioorg Med Chem 2016; 25:261-268. [PMID: 27865644 DOI: 10.1016/j.bmc.2016.10.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 10/21/2016] [Accepted: 10/27/2016] [Indexed: 10/20/2022]
Abstract
The d-/l-peptide gramicidin A (gA) is well known as a pivotal ion channel model and shows a broad spectrum of bioactivities such as antibiosis, antimalarial activity, as well as hemolysis. We applied inter-chain disulfide bonds to constrain the conformational freedom of gA into parallel and antiparallel dimeric topologies. Albeit the constructs were not found to be monoconformational, CD- and IR-spectroscopic studies suggested that this strategy indeed restricted the conformational space of the d-/l-peptide construct, and that β-helical secondary structures prevail. Correlative testing of gA dimers in antimicrobial, antimalarial, and ion conduction assays suggested that the tail-to-tail antiparallel single stranded β6.3 helix dominantly mediates the bioactivity of gA. Other conformers are unlikely to contribute to these activities. From these investigations, only weakly ion conducting gA dimers were identified that retained nM antimalarial activity.
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Affiliation(s)
- Kirtikumar B Jadhav
- Friedrich Schiller University Jena, Institute of Organic Chemistry and Macromolecular Chemistry, Humboldtstr. 10, D-07743 Jena, Germany
| | - Claudia Stein
- Center for Infectious Diseases and Infection Control, Jena University Hospital, Erlanger Allee 101, D-07747 Jena, Germany
| | - Oliwia Makarewicz
- Center for Infectious Diseases and Infection Control, Jena University Hospital, Erlanger Allee 101, D-07747 Jena, Germany
| | - Gabriele Pradel
- RWTH Aachen University, Division of Cellular and Applied Infection Biology, Worringerweg 1, D-52074 Aachen, Germany
| | - Roman J Lichtenecker
- Friedrich Schiller University Jena, Institute of Organic Chemistry and Macromolecular Chemistry, Humboldtstr. 10, D-07743 Jena, Germany
| | - Holger Sack
- Center for Molecular Biomedicine, Department of Biophysics, Friedrich Schiller University Jena and Jena University Hospital, Hans-Knöll-Str. 2, D-07745 Jena, Germany
| | - Stefan H Heinemann
- Center for Molecular Biomedicine, Department of Biophysics, Friedrich Schiller University Jena and Jena University Hospital, Hans-Knöll-Str. 2, D-07745 Jena, Germany
| | - Hans-Dieter Arndt
- Friedrich Schiller University Jena, Institute of Organic Chemistry and Macromolecular Chemistry, Humboldtstr. 10, D-07743 Jena, Germany.
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26
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Erkan D, Kayali HA. Replacement of Soybean Meal with Animal Origin Protein Meals Improved Ramoplanin A2 Production by Actinoplanes sp. ATCC 33076. Appl Biochem Biotechnol 2016; 180:306-21. [PMID: 27142271 DOI: 10.1007/s12010-016-2100-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 04/21/2016] [Indexed: 11/29/2022]
Abstract
Ramoplanin A2 is the last resort antibiotic for treatment of many high morbidity- and mortality-rated hospital infections, and it is expected to be marketed in the forthcoming years. Therefore, high-yield production of ramoplanin A2 gains importance. In this study, meat-bone meal, poultry meal, and fish meal were used instead of soybean meal for ramoplanin A2 production by Actinoplanes sp. ATCC 33076. All animal origin nitrogen sources stimulated specific productivity. Ramoplanin A2 levels were determined as 406.805 mg L(-1) in fish meal medium and 374.218 mg L(-1) in poultry meal medium. These levels were 4.25- and 4.09-fold of basal medium, respectively. However, the total yield of poultry meal was higher than that of fish meal, which is also low-priced. In addition, the variations in pH levels, protein levels, reducing sugar levels, extracellular protease, amylase and lipase activities, and intracellular free amino acid levels were monitored during the incubation period. The correlations between ramoplanin production and these variables with respect to the incubation period were determined. The intracellular levels of L-Phe, D-Orn, and L-Leu were found critical for ramoplanin A2 production. The strategy of using animal origin nitrogen sources can be applied for large-scale ramoplanin A2 production.
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Affiliation(s)
- Deniz Erkan
- Department of Biotechnology, The Graduate School of Natural and Applied Sciences, Dokuz Eylül University, 35160, Buca-Izmir, Turkey
| | - Hulya Ayar Kayali
- Department of Chemistry, Division of Biochemistry, Science Faculty, Dokuz Eylül University, 35160, Buca-Izmir, Turkey.
- Izmir Biomedicine and Genome Center, Health Campus, Dokuz Eylül University, 35340, Balcova-Izmir, Turkey.
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27
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Han J, Chen J, Shao L, Zhang J, Dong X, Liu P, Chen D. Production of the Ramoplanin Activity Analogue by Double Gene Inactivation. PLoS One 2016; 11:e0154121. [PMID: 27149627 PMCID: PMC4858212 DOI: 10.1371/journal.pone.0154121] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Accepted: 04/09/2016] [Indexed: 11/19/2022] Open
Abstract
Glycopeptides such as vancomycin and telavancin are essential for treating infections caused by Gram-positive bacteria. But the dwindling availability of new antibiotics and the emergence of resistant bacteria are making effective antibiotic treatment increasingly difficult. Ramoplanin, an inhibitor of bacterial cell wall biosynthesis, is a highly effective antibiotic against a wide range of Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus, vancomycin-intermediate resistant Clostridium difficile and vancomycin-resistant Enterococcus sp. Here, two tailoring enzyme genes in the biosynthesis of ramoplanin were deleted by double in-frame gene knockouts to produce new ramoplanin derivatives. The deschlororamoplanin A2 aglycone was purified and its structure was identified with LC-MS/MS. Deschlororamoplanin A2 aglycone and ramoplanin aglycone showed similar activity to ramoplanin A2. The results showed that α-1,2-dimannosyl disaccharide at Hpg11 and chlorination at Chp17 in the ramoplanin structure are not essential for its antimicrobial activity. This work provides new precursor compounds for the semisynthetic modification of ramoplanin.
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Affiliation(s)
- Jungang Han
- State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd., Shanghai 200040, China
| | - Junsheng Chen
- State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd., Shanghai 200040, China
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Rd., Minhang District, Shanghai 200240, China
| | - Lei Shao
- State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd., Shanghai 200040, China
- * E-mail: (DC); (LS)
| | - Junliang Zhang
- State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd., Shanghai 200040, China
| | - Xiaojing Dong
- State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd., Shanghai 200040, China
| | - Pengyu Liu
- State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd., Shanghai 200040, China
| | - Daijie Chen
- State Key Laboratory of New Drug and Pharmaceutical Process, Shanghai Institute of Pharmaceutical Industry, 1320 West Beijing Rd., Shanghai 200040, China
- * E-mail: (DC); (LS)
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References. Antibiotics (Basel) 2015. [DOI: 10.1128/9781555819316.refs] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Subramanian D, Natarajan J. Network analysis of S. aureus response to ramoplanin reveals modules for virulence factors and resistance mechanisms and characteristic novel genes. Gene 2015; 574:149-62. [DOI: 10.1016/j.gene.2015.08.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 07/30/2015] [Accepted: 08/03/2015] [Indexed: 12/27/2022]
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30
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Investigation of halogenation during the biosynthesis of ramoplanin in Actinoplanes sp. ATCC33076. Appl Microbiol Biotechnol 2015; 100:289-98. [DOI: 10.1007/s00253-015-7014-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 08/17/2015] [Accepted: 09/15/2015] [Indexed: 10/23/2022]
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Fletcher S, Yu W, Huang J, Kwasny SM, Chauhan J, Opperman TJ, MacKerell AD, de Leeuw EPH. Structure-activity exploration of a small-molecule Lipid II inhibitor. Drug Des Devel Ther 2015; 9:2383-94. [PMID: 25987836 PMCID: PMC4422293 DOI: 10.2147/dddt.s79504] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We have recently identified low-molecular weight compounds that act as inhibitors of Lipid II, an essential precursor of bacterial cell wall biosynthesis. Lipid II comprises specialized lipid (bactoprenol) linked to a hydrophilic head group consisting of a peptidoglycan subunit (N-acetyl glucosamine [GlcNAc]–N-acetyl muramic acid [MurNAc] disaccharide coupled to a short pentapeptide moiety) via a pyrophosphate. One of our lead compounds, a diphenyl-trimethyl indolene pyrylium, termed BAS00127538, interacts with the MurNAc moiety and the isoprenyl tail of Lipid II. Here, we report on the structure–activity relationship of BAS00127538 derivatives obtained by in silico analyses and de novo chemical synthesis. Our results indicate that Lipid II binding and bacterial killing are related to three features: the diphenyl moiety, the indolene moiety, and the positive charge of the pyrylium. Replacement of the pyrylium moiety with an N-methyl pyridinium, which may have importance in stability of the molecule, did not alter Lipid II binding or antibacterial potency.
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Affiliation(s)
- Steven Fletcher
- Department of Pharmaceutical Sciences, University of Maryland, School of Pharmacy, Baltimore, MD, USA
| | - Wenbo Yu
- Department of Pharmaceutical Sciences, University of Maryland, School of Pharmacy, Baltimore, MD, USA ; Computer-Aided Drug Design Center, University of Maryland, School of Pharmacy, Baltimore, MD, USA
| | - Jing Huang
- Department of Pharmaceutical Sciences, University of Maryland, School of Pharmacy, Baltimore, MD, USA ; Computer-Aided Drug Design Center, University of Maryland, School of Pharmacy, Baltimore, MD, USA
| | | | - Jay Chauhan
- Department of Pharmaceutical Sciences, University of Maryland, School of Pharmacy, Baltimore, MD, USA
| | | | - Alexander D MacKerell
- Department of Pharmaceutical Sciences, University of Maryland, School of Pharmacy, Baltimore, MD, USA ; Computer-Aided Drug Design Center, University of Maryland, School of Pharmacy, Baltimore, MD, USA
| | - Erik P H de Leeuw
- Institute of Human Virology and Department of Biochemistry and Molecular Biology, University of Maryland, School of Medicine, Baltimore, MD, USA
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32
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Wu MC, Styles MQ, Law BJC, Struck AW, Nunns L, Micklefield J. Engineered biosynthesis of enduracidin lipoglycopeptide antibiotics using the ramoplanin mannosyltransferase Ram29. MICROBIOLOGY-SGM 2015; 161:1338-47. [PMID: 25878261 PMCID: PMC4635501 DOI: 10.1099/mic.0.000095] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The lipopeptides ramoplanin from Actinoplanes sp. ATCC 33076 and enduracidin produced by Streptomyces fungicidicus are effective antibiotics against a number of drug-resistant Gram-positive pathogens. While these two antibiotics share a similar cyclic peptide structure, comprising 17 amino acids with an N-terminal fatty acid side chain, ramoplanin has a di-mannose moiety that enduracidin lacks. The mannosyl substituents of ramoplanin enhance aqueous solubility, which was important in the development of ramoplanin as a potential treatment for Clostridium difficile infections. In this study we have determined the function of the putative mannosyltransferase encoded by ram29 from the ramoplanin biosynthetic gene cluster. Bioinformatics revealed that Ram29 is an integral membrane protein with a putative DxD motif that is suggested to bind to, and activate, a polyprenyl phosphomannose donor and an extracytoplasmic C-terminal domain that is predicted to bind the ramoplanin aglycone acceptor. The ram29 gene was cloned into the tetracycline inducible plasmid pMS17 and integrated into the genome of the enduracidin producer S. fungicidicus. Induction of ram29 expression in S. fungicidicus resulted in the production of monomannosylated enduracidin derivatives, which are not present in the WT strain. Tandem MS analysis showed that mannosylation occurs on the Hpg11 residue of enduracidin. In addition to confirming the function of Ram29, these findings demonstrate how the less common, membrane-associated, polyprenyl phosphosugar-dependent glycosyltransferases can be used in natural product glycodiversification. Such a strategy may be valuable in future biosynthetic engineering approaches aimed at improving the physico-chemical and biological properties of bioactive secondary metabolites including antibiotics.
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Affiliation(s)
- Ming-Cheng Wu
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Matthew Q Styles
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Brian J C Law
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Anna-Winona Struck
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Laura Nunns
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Jason Micklefield
- School of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
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Al Toma RS, Brieke C, Cryle MJ, Süssmuth RD. Structural aspects of phenylglycines, their biosynthesis and occurrence in peptide natural products. Nat Prod Rep 2015; 32:1207-35. [DOI: 10.1039/c5np00025d] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Phenylglycine-type amino acids occur in a wide variety of peptide natural products. Herein structures and properties of these peptides as well as the biosynthetic origin and incorporation of phenylglycines are discussed.
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Affiliation(s)
| | - Clara Brieke
- Max Planck Institute for Medical Research
- Department of Biomolecular Mechanisms
- 69120 Heidelberg
- Germany
| | - Max J. Cryle
- Max Planck Institute for Medical Research
- Department of Biomolecular Mechanisms
- 69120 Heidelberg
- Germany
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34
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Cheng M, Huang JX, Ramu S, Butler MS, Cooper MA. Ramoplanin at bactericidal concentrations induces bacterial membrane depolarization in Staphylococcus aureus. Antimicrob Agents Chemother 2014; 58:6819-27. [PMID: 25182650 PMCID: PMC4249368 DOI: 10.1128/aac.00061-14] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 08/26/2014] [Indexed: 12/22/2022] Open
Abstract
Ramoplanin is an actinomycetes-derived antibiotic with broad-spectrum activity against Gram-positive bacteria that has been evaluated in clinical trials for the treatment of gastrointestinal vancomycin-resistant enterococci (VRE) and Clostridium difficile infections. Recent studies have proposed that ramoplanin binds to bacterial membranes as a C2 symmetrical dimer that can sequester Lipid II, which causes inhibition of cell wall peptidoglycan biosynthesis and cell death. In this study, ramoplanin was shown to bind to anionic and zwitterionic membrane mimetics with a higher affinity for anionic membranes and to induce membrane depolarization of methicillin-susceptible Staphylococcus aureus (MSSA) ATCC 25923 at concentrations at or above the minimal bactericidal concentration (MBC). The ultrastructural effects of ramoplanin on S. aureus were also examined by transmission electron microscopy (TEM), and this showed dramatic changes to bacterial cell morphology. The correlation observed between membrane depolarization and bacterial cell viability suggests that this mechanism may contribute to the bactericidal activity of ramoplanin.
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Affiliation(s)
- Mu Cheng
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Johnny X Huang
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Soumya Ramu
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Mark S Butler
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Matthew A Cooper
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
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35
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Schneider T, Müller A, Miess H, Gross H. Cyclic lipopeptides as antibacterial agents – Potent antibiotic activity mediated by intriguing mode of actions. Int J Med Microbiol 2014; 304:37-43. [DOI: 10.1016/j.ijmm.2013.08.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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36
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Varney KM, Bonvin AMJJ, Pazgier M, Malin J, Yu W, Ateh E, Oashi T, Lu W, Huang J, Diepeveen-de Buin M, Bryant J, Breukink E, MacKerell AD, de Leeuw EPH. Turning defense into offense: defensin mimetics as novel antibiotics targeting lipid II. PLoS Pathog 2013; 9:e1003732. [PMID: 24244161 PMCID: PMC3820767 DOI: 10.1371/journal.ppat.1003732] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 09/12/2013] [Indexed: 01/09/2023] Open
Abstract
We have previously reported on the functional interaction of Lipid II with human alpha-defensins, a class of antimicrobial peptides. Lipid II is an essential precursor for bacterial cell wall biosynthesis and an ideal and validated target for natural antibiotic compounds. Using a combination of structural, functional and in silico analyses, we present here the molecular basis for defensin-Lipid II binding. Based on the complex of Lipid II with Human Neutrophil peptide-1, we could identify and characterize chemically diverse low-molecular weight compounds that mimic the interactions between HNP-1 and Lipid II. Lead compound BAS00127538 was further characterized structurally and functionally; it specifically interacts with the N-acetyl muramic acid moiety and isoprenyl tail of Lipid II, targets cell wall synthesis and was protective in an in vivo model for sepsis. For the first time, we have identified and characterized low molecular weight synthetic compounds that target Lipid II with high specificity and affinity. Optimization of these compounds may allow for their development as novel, next generation therapeutic agents for the treatment of Gram-positive pathogenic infections. Every year, an increasing number of people are at risk for bacterial infections that cannot be effectively treated. This is because many bacteria are becoming more resistant to antibiotics. Of particular concern is the rise in hospital-acquired infections. Infection caused by the methicillin-resistant Staphylococcus aureus bacterium or MRSA is the cause of many fatalities and puts a burden on health care systems in many countries. The antibiotic of choice for treatment of S. aureus infections is vancomycin, an antimicrobial peptide that kills bacteria by binding to the bacterial cell wall component Lipid II. Here, we have identified for the first time, small synthetic compounds that also bind Lipid II with the aim to develop new antibiotic drugs to fight against bacterial infections.
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Affiliation(s)
- Kristen M. Varney
- NMR Facility, University of Maryland Baltimore School of Medicine, Baltimore, Maryland, United States of America
| | - Alexandre M. J. J. Bonvin
- Utrecht University, Bijvoet Center for Biomolecular Research, Faculty of Science-Chemistry, Utrecht, The Netherlands
| | - Marzena Pazgier
- Institute of Human Virology & Department of Biochemistry and Molecular Biology of the University of Maryland Baltimore School of Medicine, Baltimore, Maryland, United States of America
| | - Jakob Malin
- Maastricht University Medical Center, Maastricht, The Netherlands
| | - Wenbo Yu
- Department of Pharmaceutical Sciences and Computer-Aided Drug Design Center, University of Maryland, School of Pharmacy, Baltimore, Maryland, United States of America
| | - Eugene Ateh
- Institute of Human Virology & Department of Biochemistry and Molecular Biology of the University of Maryland Baltimore School of Medicine, Baltimore, Maryland, United States of America
| | - Taiji Oashi
- Department of Pharmaceutical Sciences and Computer-Aided Drug Design Center, University of Maryland, School of Pharmacy, Baltimore, Maryland, United States of America
| | - Wuyuan Lu
- Institute of Human Virology & Department of Biochemistry and Molecular Biology of the University of Maryland Baltimore School of Medicine, Baltimore, Maryland, United States of America
| | - Jing Huang
- Department of Pharmaceutical Sciences and Computer-Aided Drug Design Center, University of Maryland, School of Pharmacy, Baltimore, Maryland, United States of America
| | - Marlies Diepeveen-de Buin
- Utrecht University, Bijvoet Center for Biomolecular Research, Faculty of Science-Chemistry, Utrecht, The Netherlands
| | - Joseph Bryant
- Institute of Human Virology & Department of Biochemistry and Molecular Biology of the University of Maryland Baltimore School of Medicine, Baltimore, Maryland, United States of America
| | - Eefjan Breukink
- Utrecht University, Bijvoet Center for Biomolecular Research, Faculty of Science-Chemistry, Utrecht, The Netherlands
| | - Alexander D. MacKerell
- Department of Pharmaceutical Sciences and Computer-Aided Drug Design Center, University of Maryland, School of Pharmacy, Baltimore, Maryland, United States of America
| | - Erik P. H. de Leeuw
- Institute of Human Virology & Department of Biochemistry and Molecular Biology of the University of Maryland Baltimore School of Medicine, Baltimore, Maryland, United States of America
- * E-mail:
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37
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Chen JS, Wang YX, Shao L, Pan HX, Li JA, Lin HM, Dong XJ, Chen DJ. Functional identification of the gene encoding the enzyme involved in mannosylation in ramoplanin biosynthesis in Actinoplanes sp. Biotechnol Lett 2013; 35:1501-8. [DOI: 10.1007/s10529-013-1233-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 05/03/2013] [Indexed: 10/26/2022]
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38
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Bionda N, Pitteloud JP, Cudic P. Cyclic lipodepsipeptides: a new class of antibacterial agents in the battle against resistant bacteria. Future Med Chem 2013; 5:1311-30. [PMID: 23859209 PMCID: PMC3845972 DOI: 10.4155/fmc.13.86] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In order to provide effective treatment options for infections caused by multidrug-resistant bacteria, innovative antibiotics are necessary, preferably with novel modes of action and/or belonging to novel classes of drugs. Naturally occurring cyclic lipodepsipeptides, which contain one or more ester bonds along with the amide bonds, have emerged as promising candidates for the development of new antibiotics. Some of these natural products are either already marketed or in advanced stages of clinical development. However, despite the progress in the development of new antibacterial agents, it is inevitable that resistant strains of bacteria will emerge in response to the widespread use of a particular antibiotic and limit its lifetime. Therefore, development of new antibiotics remains our most efficient way to counteract bacterial resistance.
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Affiliation(s)
- Nina Bionda
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Post St Lucie, FL 34987, USA
| | - Jean-Philippe Pitteloud
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Post St Lucie, FL 34987, USA
| | - Predrag Cudic
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Post St Lucie, FL 34987, USA
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39
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Production of ramoplanin analogues by genetic engineering of Actinoplanes sp. Biotechnol Lett 2013; 35:1685-92. [DOI: 10.1007/s10529-013-1261-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 05/31/2013] [Indexed: 10/26/2022]
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40
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Analysis of anti-Clostridium difficile activity of thuricin CD, vancomycin, metronidazole, ramoplanin, and actagardine, both singly and in paired combinations. Antimicrob Agents Chemother 2013; 57:2882-6. [PMID: 23571539 DOI: 10.1128/aac.00261-13] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Due to the ongoing problem of recurrence of Clostridium difficile-associated diarrhea following antibiotic treatment, there is an urgent need for alternative treatment options. We assessed the MICs of five antimicrobials singly and in combinations against a range of C. difficile clinical isolates. Ramoplanin-actagardine combinations were particularly effective, with partial synergistic/additive effects observed against 61.5% of C. difficile strains tested.
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41
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Hänchen A, Rausch S, Landmann B, Toti L, Nusser A, Süssmuth RD. Alanine scan of the peptide antibiotic feglymycin: assessment of amino acid side chains contributing to antimicrobial activity. Chembiochem 2013; 14:625-32. [PMID: 23447362 DOI: 10.1002/cbic.201300032] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Indexed: 01/08/2023]
Abstract
The antibiotic feglymycin is a linear 13-mer peptide synthesized by the bacterium Streptomyces sp. DSM 11171. It mainly consists of the nonproteinogenic amino acids 4-hydroxyphenylglycine and 3,5-dihydroxyphenylglycine. An alanine scan of feglymycin was performed by solution-phase peptide synthesis in order to assess the significance of individual amino acid side chains for biological activity. Hence, 13 peptides were synthesized from di- and tripeptide building blocks, and subsequently tested for antibacterial activity against Staphylococcus aureus strains. Furthermore we tested the inhibition of peptidoglycan biosynthesis enzymes MurA and MurC, which are inhibited by feglymycin. Whereas the antibacterial activity is significantly based on the three amino acids D-Hpg1, L-Hpg5, and L-Phe12, the inhibitory activity against MurA and MurC depends mainly on L-Asp13. The difference in the position dependence for antibacterial activity and enzyme inhibition suggests multiple molecular targets in the modes of action of feglymycin.
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Affiliation(s)
- Anne Hänchen
- Technische Universität Berlin, Fakultät II, Institut für Chemie, Strasse des 17. Juni 124, 10623 Berlin, Germany
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42
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Pan HX, Li JA, Shao L, Zhu CB, Chen JS, Tang GL, Chen DJ. Genetic manipulation revealing an unusual N-terminal region in a stand-alone non-ribosomal peptide synthetase involved in the biosynthesis of ramoplanins. Biotechnol Lett 2012; 35:107-14. [DOI: 10.1007/s10529-012-1056-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 09/10/2012] [Indexed: 01/08/2023]
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Gandolfi R, Marinelli F, Ragg E, Romano D, Molinari F. Chemoenzymatic deacylation of ramoplanin. Bioorg Med Chem Lett 2012; 22:5283-7. [PMID: 22795330 DOI: 10.1016/j.bmcl.2012.06.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Revised: 06/14/2012] [Accepted: 06/14/2012] [Indexed: 10/28/2022]
Abstract
The chemoenzymatic deacylation of ramoplanin A2 is described for the first time: ramoplanin A2 was Boc-protected and hydrogenated to Boc-protected tetrahydroramoplanin, which was subsequently deacylated using an acylase from Actinoplanes utahensis NRRL 12052. The chemoenzymatic process proceeded with 80% overall yield, which favourably compares with the previously described chemical deacylation.
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Affiliation(s)
- Raffaella Gandolfi
- Dipartimento di Scienze Farmaceutiche, Via Venezian 21, 20133 Milano, Italy
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44
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Bionda N, Stawikowski M, Stawikowska R, Cudic M, López-Vallejo F, Treitl D, Medina-Franco J, Cudic P. Effects of cyclic lipodepsipeptide structural modulation on stability, antibacterial activity, and human cell toxicity. ChemMedChem 2012; 7:871-82. [PMID: 22392790 PMCID: PMC3500847 DOI: 10.1002/cmdc.201200016] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 02/09/2012] [Indexed: 11/07/2022]
Abstract
Bacterial infections are becoming increasingly difficult to treat due to the development and spread of antibiotic resistance. Therefore, identifying novel antibacterial targets and new antibacterial agents capable of treating infections by drug-resistant bacteria is of vital importance. The structurally simple yet potent fusaricidin or LI-F class of natural products represents a particularly attractive source of candidates for the development of new antibacterial agents. We synthesized 18 fusaricidin/LI-F analogues and investigated the effects of structure modification on their conformation, serum stability, antibacterial activity, and toxicity toward human cells. Our findings show that substitution of an ester bond in depsipeptides with an amide bond may afford equally potent analogues with improved stability and greatly decreased cytotoxicity. The lower overall hydrophobicity/amphiphilicity of amide analogues in comparison with their parent depsipeptides, as indicated by HPLC retention times, may explain the dissociation of antibacterial activity and human cell cytotoxicity. These results indicate that amide analogues may have significant advantages over fusaricidin/LI-F natural products and their depsipeptide analogues as lead structures for the development of new antibacterial agents.
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Affiliation(s)
- Nina Bionda
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, Florida 34987 (USA), Fax: (+1) 772-345-3649
- Department of Chemistry and BIochemistry, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431 (USA)
| | - Maciej Stawikowski
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, Florida 34987 (USA), Fax: (+1) 772-345-3649
| | - Roma Stawikowska
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, Florida 34987 (USA), Fax: (+1) 772-345-3649
| | - Maré Cudic
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, Florida 34987 (USA), Fax: (+1) 772-345-3649
| | - Fabian López-Vallejo
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, Florida 34987 (USA), Fax: (+1) 772-345-3649
| | - Daniela Treitl
- Department of Chemistry and BIochemistry, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431 (USA)
| | - José Medina-Franco
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, Florida 34987 (USA), Fax: (+1) 772-345-3649
| | - Predrag Cudic
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, Florida 34987 (USA), Fax: (+1) 772-345-3649
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45
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Economou NJ, Nahoum V, Weeks SD, Grasty KC, Zentner IJ, Townsend TM, Bhuiya MW, Cocklin S, Loll PJ. A carrier protein strategy yields the structure of dalbavancin. J Am Chem Soc 2012; 134:4637-45. [PMID: 22352468 DOI: 10.1021/ja208755j] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Many large natural product antibiotics act by specifically binding and sequestering target molecules found on bacterial cells. We have developed a new strategy to expedite the structural analysis of such antibiotic-target complexes, in which we covalently link the target molecules to carrier proteins, and then crystallize the entire carrier-target-antibiotic complex. Using native chemical ligation, we have linked the Lys-D-Ala-D-Ala binding epitope for glycopeptide antibiotics to three different carrier proteins. We show that recognition of this peptide by multiple antibiotics is not compromised by the presence of the carrier protein partner, and use this approach to determine the first-ever crystal structure for the new therapeutic dalbavancin. We also report the first crystal structure of an asymmetric ristocetin antibiotic dimer, as well as the structure of vancomycin bound to a carrier-target fusion. The dalbavancin structure reveals an antibiotic molecule that has closed around its binding partner; it also suggests mechanisms by which the drug can enhance its half-life by binding to serum proteins, and be targeted to bacterial membranes. Notably, the carrier protein approach is not limited to peptide ligands such as Lys-D-Ala-D-Ala, but is applicable to a diverse range of targets. This strategy is likely to yield structural insights that accelerate new therapeutic development.
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Affiliation(s)
- Nicoleta J Economou
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19102, United States
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46
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Hoertz AJ, Hamburger JB, Gooden DM, Bednar MM, McCafferty DG. Studies on the biosynthesis of the lipodepsipeptide antibiotic Ramoplanin A2. Bioorg Med Chem 2012; 20:859-65. [DOI: 10.1016/j.bmc.2011.11.062] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 11/22/2011] [Accepted: 11/28/2011] [Indexed: 11/16/2022]
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47
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Hao H, Cheng G, Dai M, Wu Q, Yuan Z. Inhibitors targeting on cell wall biosynthesis pathway of MRSA. MOLECULAR BIOSYSTEMS 2012; 8:2828-38. [DOI: 10.1039/c2mb25188d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Peptide antibiotic sensing and detoxification modules of Bacillus subtilis. Antimicrob Agents Chemother 2010; 55:515-25. [PMID: 21078927 DOI: 10.1128/aac.00352-10] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Peptide antibiotics are produced by a wide range of microorganisms. Most of them target the cell envelope, often by inhibiting cell wall synthesis. One of the resistance mechanisms against antimicrobial peptides is a detoxification module consisting of a two-component system and an ABC transporter. Upon the detection of such a compound, the two-component system induces the expression of the ABC transporter, which in turn removes the antibiotic from its site of action, mediating the resistance of the cell. Three such peptide antibiotic-sensing and detoxification modules are present in Bacillus subtilis. Here we show that each of these modules responds to a number of peptides and confers resistance against them. BceRS-BceAB (BceRS-AB) responds to bacitracin, plectasin, mersacidin, and actagardine. YxdJK-LM is induced by a cationic antimicrobial peptide, LL-37. The PsdRS-AB (formerly YvcPQ-RS) system responds primarily to lipid II-binding lantibiotics such as nisin and gallidermin. We characterized the psdRS-AB operon and defined the regulatory sequences within the P(psdA) promoter. Mutation analysis demonstrated that P(psdA) expression is fully PsdR dependent. The features of both the P(bceA) and P(psdA) promoters make them promising candidates as novel whole-cell biosensors that can easily be adjusted for high-throughput screening.
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A family of diiron monooxygenases catalyzing amino acid beta-hydroxylation in antibiotic biosynthesis. Proc Natl Acad Sci U S A 2010; 107:15391-6. [PMID: 20713732 DOI: 10.1073/pnas.1007953107] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The biosynthesis of chloramphenicol requires a beta-hydroxylation tailoring reaction of the precursor L-p-aminophenylalanine (L-PAPA). Here, it is shown that this reaction is catalyzed by the enzyme CmlA from an operon containing the genes for biosynthesis of L-PAPA and the nonribosomal peptide synthetase CmlP. EPR, Mössbauer, and optical spectroscopies reveal that CmlA contains an oxo-bridged dinuclear iron cluster, a metal center not previously associated with nonribosomal peptide synthetase chemistry. Single-turnover kinetic studies indicate that CmlA is functional in the diferrous state and that its substrate is L-PAPA covalently bound to CmlP. Analytical studies show that the product is hydroxylated L-PAPA and that O(2) is the oxygen source, demonstrating a monooxygenase reaction. The gene sequence of CmlA shows that it utilizes a lactamase fold, suggesting that the diiron cluster is in a protein environment not previously known to effect monooxygenase reactions. Notably, CmlA homologs are widely distributed in natural product biosynthetic pathways, including a variety of pharmaceutically important beta-hydroxylated antibiotics and cytostatics.
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Schmidt JW, Greenough A, Burns M, Luteran AE, McCafferty DG. Generation of ramoplanin-resistant Staphylococcus aureus. FEMS Microbiol Lett 2010; 310:104-11. [PMID: 20659164 DOI: 10.1111/j.1574-6968.2010.02051.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Ramoplanin is a lipoglycodepsipeptide antimicrobial active against clinically important Gram-positive bacteria including methicillin-resistant Staphylococcus aureus. To proactively examine ramoplanin resistance, we subjected S. aureus NCTC 8325-4 to serial passage in the presence of increasing concentrations of ramoplanin, generating the markedly resistant strain RRSA16. Susceptibility testing of RRSA16 revealed the unanticipated acquisition of cross-resistance to vancomycin and nisin. RRSA16 displayed phenotypes, including a thickened cell wall and reduced susceptibility to Triton X-100-induced autolysis, which are associated with vancomycin intermediate-resistant S. aureus strains. Passage of RRSA16 for 18 days in a drug-free medium yielded strain R16-18d with restored antibiotic susceptibility. The RRSA16 isolate may be used to identify the genetic and biochemical basis for ramoplanin resistance and to further our understanding of the evolution of antibiotic cross-resistance mechanisms in S. aureus.
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Affiliation(s)
- John W Schmidt
- Department of Chemistry, Duke University, Durham, NC, USA
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