1
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Chen J, Wang W, Hu X, Yue Y, Lu X, Wang C, Wei B, Zhang H, Wang H. Medium-sized peptides from microbial sources with potential for antibacterial drug development. Nat Prod Rep 2024; 41:1235-1263. [PMID: 38651516 DOI: 10.1039/d4np00002a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Covering: 1993 to the end of 2022As the rapid development of antibiotic resistance shrinks the number of clinically available antibiotics, there is an urgent need for novel options to fill the existing antibiotic pipeline. In recent years, antimicrobial peptides have attracted increased interest due to their impressive broad-spectrum antimicrobial activity and low probability of antibiotic resistance. However, macromolecular antimicrobial peptides of plant and animal origin face obstacles in antibiotic development because of their extremely short elimination half-life and poor chemical stability. Herein, we focus on medium-sized antibacterial peptides (MAPs) of microbial origin with molecular weights below 2000 Da. The low molecular weight is not sufficient to form complex protein conformations and is also associated to a better chemical stability and easier modifications. Microbially-produced peptides are often composed of a variety of non-protein amino acids and terminal modifications, which contribute to improving the elimination half-life of compounds. Therefore, MAPs have great potential for drug discovery and are likely to become key players in the development of next-generation antibiotics. In this review, we provide a detailed exploration of the modes of action demonstrated by 45 MAPs and offer a concise summary of the structure-activity relationships observed in these MAPs.
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Affiliation(s)
- Jianwei Chen
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Wei Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xubin Hu
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yujie Yue
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xingyue Lu
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Chenjie Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Bin Wei
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Huawei Zhang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
| | - Hong Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, China
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2
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Dutta A, Sharma P, Dass D, Yarlagadda V. Exploring the Darobactin Class of Antibiotics: A Comprehensive Review from Discovery to Recent Advancements. ACS Infect Dis 2024; 10:2584-2599. [PMID: 39028949 DOI: 10.1021/acsinfecdis.4c00412] [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: 07/21/2024]
Abstract
The prevalence of antimicrobial resistance in Gram-negative bacteria poses a greater challenge due to their intrinsic resistance to many antibiotics. Recently, darobactins have emerged as a novel class of antibiotics originating from previously unexplored Gram-negative bacterial species such as Photorhabdus, Vibrio, Pseudoalteromonas and Yersinia. Darobactins belong to the ribosomally synthesized and post-translationally modified peptide (RiPP) class of antibiotics, exhibiting selective activity against Gram-negative bacteria. They target the β-barrel assembly machinery (BAM), which is crucial for the maturation and insertion of outer membrane proteins in Gram-negative bacteria. The dar operon in the producer's genome encodes for the synthesis of darobactins, which are characterized by a fused ring system connected via an alkyl-aryl ether linkage (C-O-C) and a C-C cross-link. The enzyme DarE, using the radical S-adenosyl-l-methionine (rSAM), facilitates the formation of these bonds. Biosynthetic manipulation of the darobactin gene cluster, along with its expression in a surrogate host, has enabled access to diverse darobactin analogues with variable antibiotic activities. Recently, two independent research groups successfully achieved the total synthesis of darobactin, employing Larock heteroannulation to construct the bicyclic structure. This paper presents a comprehensive review of darobactins, encompassing their discovery through to the most recent advancements.
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Affiliation(s)
- Akash Dutta
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Peehu Sharma
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Dharam Dass
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
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3
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Lewis K, Lee RE, Brötz-Oesterhelt H, Hiller S, Rodnina MV, Schneider T, Weingarth M, Wohlgemuth I. Sophisticated natural products as antibiotics. Nature 2024; 632:39-49. [PMID: 39085542 DOI: 10.1038/s41586-024-07530-w] [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: 12/28/2022] [Accepted: 05/07/2024] [Indexed: 08/02/2024]
Abstract
In this Review, we explore natural product antibiotics that do more than simply inhibit an active site of an essential enzyme. We review these compounds to provide inspiration for the design of much-needed new antibacterial agents, and examine the complex mechanisms that have evolved to effectively target bacteria, including covalent binders, inhibitors of resistance, compounds that utilize self-promoted entry, those that evade resistance, prodrugs, target corrupters, inhibitors of 'undruggable' targets, compounds that form supramolecular complexes, and selective membrane-acting agents. These are exemplified by β-lactams that bind covalently to inhibit transpeptidases and β-lactamases, siderophore chimeras that hijack import mechanisms to smuggle antibiotics into the cell, compounds that are activated by bacterial enzymes to produce reactive molecules, and antibiotics such as aminoglycosides that corrupt, rather than merely inhibit, their targets. Some of these mechanisms are highly sophisticated, such as the preformed β-strands of darobactins that target the undruggable β-barrel chaperone BamA, or teixobactin, which binds to a precursor of peptidoglycan and then forms a supramolecular structure that damages the membrane, impeding the emergence of resistance. Many of the compounds exhibit more than one notable feature, such as resistance evasion and target corruption. Understanding the surprising complexity of the best antimicrobial compounds provides a roadmap for developing novel compounds to address the antimicrobial resistance crisis by mining for new natural products and inspiring us to design similarly sophisticated antibiotics.
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Affiliation(s)
- Kim Lewis
- Antimicrobial Discovery Center, Northeastern University, Boston, MA, USA.
| | - Richard E Lee
- Department of Chemical Biology and Therapeutics, St Jude Children's Research Hospital, Memphis, TN, USA.
| | - Heike Brötz-Oesterhelt
- Interfaculty Institute of Microbiology and Infection Medicine, Tubingen, Germany
- Controlling Microbes to Fight Infection-Cluster of Excellence, Tubingen, Germany
| | | | - Marina V Rodnina
- Max Planck Institute for Multidisciplinary Sciences, Goettingen, Germany
| | - Tanja Schneider
- Institute for Pharmaceutical Microbiology, University of Bonn, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Cologne-Bonn, Bonn, Germany
| | - Markus Weingarth
- Chemistry Department, Utrecht University, Utrecht, the Netherlands
| | - Ingo Wohlgemuth
- Max Planck Institute for Multidisciplinary Sciences, Goettingen, Germany
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4
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Butler MS, Vollmer W, Goodall ECA, Capon RJ, Henderson IR, Blaskovich MAT. A Review of Antibacterial Candidates with New Modes of Action. ACS Infect Dis 2024. [PMID: 39018341 DOI: 10.1021/acsinfecdis.4c00218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/19/2024]
Abstract
There is a lack of new antibiotics to combat drug-resistant bacterial infections that increasingly threaten global health. The current pipeline of clinical-stage antimicrobials is primarily populated by "new and improved" versions of existing antibiotic classes, supplemented by several novel chemical scaffolds that act on traditional targets. The lack of fresh chemotypes acting on previously unexploited targets (the "holy grail" for new antimicrobials due to their scarcity) is particularly unfortunate as these offer the greatest opportunity for innovative breakthroughs to overcome existing resistance. In recognition of their potential, this review focuses on this subset of high value antibiotics, providing chemical structures where available. This review focuses on candidates that have progressed to clinical trials, as well as selected examples of promising pioneering approaches in advanced stages of development, in order to stimulate additional research aimed at combating drug-resistant infections.
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Affiliation(s)
- Mark S Butler
- Centre for Superbug Solutions and ARC Training Centre for Environmental and Agricultural Solutions to Antimicrobial Resistance, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Waldemar Vollmer
- Centre for Superbug Solutions and ARC Training Centre for Environmental and Agricultural Solutions to Antimicrobial Resistance, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Emily C A Goodall
- Centre for Superbug Solutions and ARC Training Centre for Environmental and Agricultural Solutions to Antimicrobial Resistance, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Robert J Capon
- Centre for Superbug Solutions and ARC Training Centre for Environmental and Agricultural Solutions to Antimicrobial Resistance, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Ian R Henderson
- Centre for Superbug Solutions and ARC Training Centre for Environmental and Agricultural Solutions to Antimicrobial Resistance, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Mark A T Blaskovich
- Centre for Superbug Solutions and ARC Training Centre for Environmental and Agricultural Solutions to Antimicrobial Resistance, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
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5
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Pfeiffer IPM, Schröder MP, Mordhorst S. Opportunities and challenges of RiPP-based therapeutics. Nat Prod Rep 2024; 41:990-1019. [PMID: 38411278 DOI: 10.1039/d3np00057e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Covering: up to 2024Ribosomally synthesised and post-translationally modified peptides (RiPPs) comprise a substantial group of peptide natural products exhibiting noteworthy bioactivities ranging from antiinfective to anticancer and analgesic effects. Furthermore, RiPP biosynthetic pathways represent promising production routes for complex peptide drugs, and the RiPP technology is well-suited for peptide engineering to produce derivatives with specific functions. Thus, RiPP natural products possess features that render them potentially ideal candidates for drug discovery and development. Nonetheless, only a small number of RiPP-derived compounds have successfully reached the market thus far. This review initially outlines the therapeutic opportunities that RiPP-based compounds can offer, whilst subsequently discussing the limitations that require resolution in order to fully exploit the potential of RiPPs towards the development of innovative drugs.
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Affiliation(s)
- Isabel P-M Pfeiffer
- University of Tübingen, Pharmaceutical Institute, Department of Pharmaceutical Biology, Auf der Morgenstelle 8, 72076 Tübingen, Germany.
| | - Maria-Paula Schröder
- University of Tübingen, Pharmaceutical Institute, Department of Pharmaceutical Biology, Auf der Morgenstelle 8, 72076 Tübingen, Germany.
| | - Silja Mordhorst
- University of Tübingen, Pharmaceutical Institute, Department of Pharmaceutical Biology, Auf der Morgenstelle 8, 72076 Tübingen, Germany.
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6
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Woodard AM, Peccati F, Navo CD, Jiménez-Osés G, Mitchell DA. Darobactin Substrate Engineering and Computation Show Radical Stability Governs Ether versus C-C Bond Formation. J Am Chem Soc 2024; 146:14328-14340. [PMID: 38728535 PMCID: PMC11225102 DOI: 10.1021/jacs.4c03994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
The Gram-negative selective antibiotic darobactin A has attracted interest owing to its intriguing fused bicyclic structure and unique targeting of the outer membrane protein BamA. Darobactin, a ribosomally synthesized and post-translationally modified peptide (RiPP), is produced by a radical S-adenosyl methionine (rSAM)-dependent enzyme (DarE) and contains one ether and one C-C cross-link. Herein, we analyze the substrate tolerance of DarE and describe an underlying catalytic principle of the enzyme. These efforts produced 51 enzymatically modified darobactin variants, revealing that DarE can install the ether and C-C cross-links independently and in different locations on the substrate. Notable variants with fused bicyclic structures were characterized, including darobactin W3Y, with a non-Trp residue at the twice-modified central position, and darobactin K5F, which displays a fused diether ring pattern. While lacking antibiotic activity, quantum mechanical modeling of darobactins W3Y and K5F aided in the elucidation of the requisite features for high-affinity BamA engagement. We also provide experimental evidence for β-oxo modification, which adds support for a proposed DarE mechanism. Based on these results, ether and C-C cross-link formation was investigated computationally, and it was determined that more stable and longer-lived aromatic Cβ radicals correlated with ether formation. Further, molecular docking and transition state structures based on high-level quantum mechanical calculations support the different indole connectivity observed for ether (Trp-C7) and C-C (Trp-C6) cross-links. Finally, mutational analysis and protein structural predictions identified substrate residues that govern engagement to DarE. Our work informs on darobactin scaffold engineering and further unveils the underlying principles of rSAM catalysis.
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Affiliation(s)
- Austin M Woodard
- Department of Chemistry, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
| | - Francesca Peccati
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain
| | - Claudio D Navo
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain
| | - Gonzalo Jiménez-Osés
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Douglas A Mitchell
- Department of Chemistry, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
- Department of Microbiology, University of Illinois at Urbana─Champaign, Urbana, Illinois 61801, United States
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7
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Abstract
Covering: 2016 to 2023Ribosomally synthesized and posttranslationally modified peptides (RiPPs) continue to be a rich source of chemically diverse and bioactive peptide natural products. In recent years, cyclophane-containing RiPP natural products and their biosynthetic pathways have been more frequently encountered. This highlight will focus on bacterial monoaryl cyclophane-containing RiPPs. This class of RiPPs is produced by radical SAM/SPASM enzymes that form a crosslink between the aromatic ring and sidechain of two amino acid residues of the precursor peptide. Selected natural products from these pathways exhibit specific antibacterial activity against gram-negative pathogens. The approaches used to discover these pathways and products will be described and categorized as natural product-first or enzyme-first. The breadth of ring systems formed by the enzymes, enzyme mechanism, and recent reports of synthetic methods for constructing these ring systems will also be presented. Bacterial cyclophane-containing RiPPs and their biosynthetic enzymes represent an untapped source of scaffolds for drug discovery and tools for synthetic biology.
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Affiliation(s)
- Chin-Soon Phan
- Department of Pharmacy, National University of Singapore, 4 Science Dr 2, Singapore 117544, Singapore.
| | - Brandon I Morinaka
- Department of Pharmacy, National University of Singapore, 4 Science Dr 2, Singapore 117544, Singapore.
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8
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Li H, Ding W, Zhang Q. Discovery and engineering of ribosomally synthesized and post-translationally modified peptide (RiPP) natural products. RSC Chem Biol 2024; 5:90-108. [PMID: 38333193 PMCID: PMC10849128 DOI: 10.1039/d3cb00172e] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 11/17/2023] [Indexed: 02/10/2024] Open
Abstract
Ribosomally synthesized and post-translationally modified peptides (RiPPs) represent a diverse superfamily of natural products with immense potential for drug development. This review provides a concise overview of the recent advances in the discovery of RiPP natural products, focusing on rational strategies such as bioactivity guided screening, enzyme or precursor-based genome mining, and biosynthetic engineering. The challenges associated with activating silent biosynthetic gene clusters and the development of elaborate catalytic systems are also discussed. The logical frameworks emerging from these research studies offer valuable insights into RiPP biosynthesis and engineering, paving the way for broader pharmaceutic applications of these peptide natural products.
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Affiliation(s)
- He Li
- Department of Chemistry, Fudan University Shanghai 200433 China
| | - Wei Ding
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University Shanghai 200240 China
| | - Qi Zhang
- Department of Chemistry, Fudan University Shanghai 200433 China
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9
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George A, Patil AG, Mahalakshmi R. ATP-independent assembly machinery of bacterial outer membranes: BAM complex structure and function set the stage for next-generation therapeutics. Protein Sci 2024; 33:e4896. [PMID: 38284489 PMCID: PMC10804688 DOI: 10.1002/pro.4896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 12/28/2023] [Accepted: 12/31/2023] [Indexed: 01/30/2024]
Abstract
Diderm bacteria employ β-barrel outer membrane proteins (OMPs) as their first line of communication with their environment. These OMPs are assembled efficiently in the asymmetric outer membrane by the β-Barrel Assembly Machinery (BAM). The multi-subunit BAM complex comprises the transmembrane OMP BamA as its functional subunit, with associated lipoproteins (e.g., BamB/C/D/E/F, RmpM) varying across phyla and performing different regulatory roles. The ability of BAM complex to recognize and fold OM β-barrels of diverse sizes, and reproducibly execute their membrane insertion, is independent of electrochemical energy. Recent atomic structures, which captured BAM-substrate complexes, show the assembly function of BamA can be tailored, with different substrate types exhibiting different folding mechanisms. Here, we highlight common and unique features of its interactome. We discuss how this conserved protein complex has evolved the ability to effectively achieve the directed assembly of diverse OMPs of wide-ranging sizes (8-36 β-stranded monomers). Additionally, we discuss how darobactin-the first natural membrane protein inhibitor of Gram-negative bacteria identified in over five decades-selectively targets and specifically inhibits BamA. We conclude by deliberating how a detailed deduction of BAM complex-associated regulation of OMP biogenesis and OM remodeling will open avenues for the identification and development of effective next-generation therapeutics against Gram-negative pathogens.
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Affiliation(s)
- Anjana George
- Molecular Biophysics Laboratory, Department of Biological SciencesIndian Institute of Science Education and ResearchBhopalIndia
| | - Akanksha Gajanan Patil
- Molecular Biophysics Laboratory, Department of Biological SciencesIndian Institute of Science Education and ResearchBhopalIndia
| | - Radhakrishnan Mahalakshmi
- Molecular Biophysics Laboratory, Department of Biological SciencesIndian Institute of Science Education and ResearchBhopalIndia
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10
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Seyfert C, Müller AV, Walsh DJ, Birkelbach J, Kany AM, Porten C, Yuan B, Krug D, Herrmann J, Marlovits TC, Hirsch AKH, Müller R. New Genetically Engineered Derivatives of Antibacterial Darobactins Underpin Their Potential for Antibiotic Development. J Med Chem 2023; 66:16330-16341. [PMID: 38093695 PMCID: PMC10726357 DOI: 10.1021/acs.jmedchem.3c01660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/02/2023] [Accepted: 11/06/2023] [Indexed: 12/18/2023]
Abstract
Biosynthetic engineering of bicyclic darobactins, selectively sealing the lateral gate of the outer membrane protein BamA, leads to active analogues, which are up to 128-fold more potent against Gram-negative pathogens compared to native counterparts. Because of their excellent antibacterial activity, darobactins represent one of the most promising new antibiotic classes of the past decades. Here, we present a series of structure-driven biosynthetic modifications of our current frontrunner, darobactin 22 (D22), to investigate modifications at the understudied positions 2, 4, and 5 for their impact on bioactivity. Novel darobactins were found to be highly active against critical pathogens from the WHO priority list. Antibacterial activity data were corroborated by dissociation constants with BamA. The most active derivatives D22 and D69 were subjected to ADMET profiling, showing promising features. We further evaluated D22 and D69 for bioactivity against multidrug-resistant clinical isolates and found them to have strong activity.
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Affiliation(s)
- Carsten
E. Seyfert
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Alison V. Müller
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Danica J. Walsh
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Joy Birkelbach
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Andreas M. Kany
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Christoph Porten
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Biao Yuan
- Institute
of Structural and Systems Biology and Centre for Structural Systems
Biology (CSSB), University Medical Center
Hamburg-Eppendorf (UKE), Hamburg 22607, Germany
- Deutsches
Elektronen-Synchrotron Zentrum (DESY), Hamburg 22607, Germany
- Centre for
Structural Systems Biology (CSSB), Hamburg 22607, Germany
| | - Daniel Krug
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Jennifer Herrmann
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
| | - Thomas C. Marlovits
- Institute
of Structural and Systems Biology and Centre for Structural Systems
Biology (CSSB), University Medical Center
Hamburg-Eppendorf (UKE), Hamburg 22607, Germany
- Deutsches
Elektronen-Synchrotron Zentrum (DESY), Hamburg 22607, Germany
- Centre for
Structural Systems Biology (CSSB), Hamburg 22607, Germany
| | - Anna K. H. Hirsch
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
- Helmholtz
International Lab for Anti-Infectives, Saarbrücken 66123, Germany
| | - Rolf Müller
- Helmholtz
Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre
for Infection Research (HZI) and Saarland University Department of
Pharmacy, Saarbrücken 66123, Germany
- German
Centre for Infection Research (DZIF),
partner site, Hannover, Braunschweig 38124, Germany
- Helmholtz
International Lab for Anti-Infectives, Saarbrücken 66123, Germany
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11
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Theuretzbacher U, Blasco B, Duffey M, Piddock LJV. Unrealized targets in the discovery of antibiotics for Gram-negative bacterial infections. Nat Rev Drug Discov 2023; 22:957-975. [PMID: 37833553 DOI: 10.1038/s41573-023-00791-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2023] [Indexed: 10/15/2023]
Abstract
Advances in areas that include genomics, systems biology, protein structure determination and artificial intelligence provide new opportunities for target-based antibacterial drug discovery. The selection of a 'good' new target for direct-acting antibacterial compounds is the first decision, for which multiple criteria must be explored, integrated and re-evaluated as drug discovery programmes progress. Criteria include essentiality of the target for bacterial survival, its conservation across different strains of the same species, bacterial species and growth conditions (which determines the spectrum of activity of a potential antibiotic) and the level of homology with human genes (which influences the potential for selective inhibition). Additionally, a bacterial target should have the potential to bind to drug-like molecules, and its subcellular location will govern the need for inhibitors to penetrate one or two bacterial membranes, which is a key challenge in targeting Gram-negative bacteria. The risk of the emergence of target-based drug resistance for drugs with single targets also requires consideration. This Review describes promising but as-yet-unrealized targets for antibacterial drugs against Gram-negative bacteria and examples of cognate inhibitors, and highlights lessons learned from past drug discovery programmes.
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Affiliation(s)
| | - Benjamin Blasco
- Global Antibiotic Research and Development Partnership (GARDP), Geneva, Switzerland
| | - Maëlle Duffey
- Global Antibiotic Research and Development Partnership (GARDP), Geneva, Switzerland
| | - Laura J V Piddock
- Global Antibiotic Research and Development Partnership (GARDP), Geneva, Switzerland.
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12
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Woodard AM, Peccati F, Navo CD, Jiménez-Osés G, Mitchell DA. Benzylic Radical Stabilization Permits Ether Formation During Darobactin Biosynthesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.29.569256. [PMID: 38076856 PMCID: PMC10705402 DOI: 10.1101/2023.11.29.569256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
The Gram-negative selective antibiotic darobactin A has attracted interest owing to its intriguing fused bicyclic structure and unique mode of action. Biosynthetic studies have revealed that darobactin is a ribosomally synthesized and post-translationally modified peptide (RiPP). During maturation, the darobactin precursor peptide (DarA) is modified by a radical S-adenosyl methionine (rSAM)-dependent enzyme (DarE) to contain ether and C-C crosslinks. In this work, we describe the enzymatic tolerance of DarE using a panel of DarA variants, revealing that DarE can install the ether and C-C crosslinks independently and in different locations on DarA. These efforts produced 57 darobactin variants, 50 of which were enzymatically modified. Several new variants with fused bicyclic structures were characterized, including darobactin W3Y, which replaces tryptophan with tyrosine at the twice-modified central position, and darobactin K5F, which displays a fused diether ring pattern. Three additional darobactin variants contained fused diether macrocycles, leading us to investigate the origin of ether versus C-C crosslink formation. Computational analyses found that more stable and long-lived Cβ radicals found on aromatic amino acids correlated with ether formation. Further, molecular docking and calculated transition state structures provide support for the different indole connectivity observed for ether (Trp-C7) and C-C (Trp-C6) crosslink formation. We also provide experimental evidence for a β-oxotryptophan modification, a proposed intermediate during ether crosslink formation. Finally, mutational analysis of the DarA leader region and protein structural predictions identified which residues were dispensable for processing and others that govern substrate engagement by DarE. Our work informs on darobactin scaffold engineering and sheds additional light on the underlying principles of rSAM catalysis.
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Affiliation(s)
- Austin M. Woodard
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Francesca Peccati
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain
| | - Claudio D. Navo
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain
| | - Gonzalo Jiménez-Osés
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160 Derio, Spain
- Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Douglas A. Mitchell
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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13
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Ma S, Xi W, Wang S, Chen H, Guo S, Mo T, Chen W, Deng Z, Chen F, Ding W, Zhang Q. Substrate-Controlled Catalysis in the Ether Cross-Link-Forming Radical SAM Enzymes. J Am Chem Soc 2023; 145:22945-22953. [PMID: 37769281 DOI: 10.1021/jacs.3c04355] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
Darobactin is a heptapeptide antibiotic featuring an ether cross-link and a C-C cross-link, and both cross-links are installed by a radical S-adenosylmethionine (rSAM) enzyme DarE. How a single DarE enzyme affords the two chemically distinct cross-links remains largely obscure. Herein, by mapping the biosynthetic landscape for darobactin-like RiPP (daropeptide), we identified and characterized two novel daropeptides that lack the C-C cross-link present in darobactin and instead are solely composed of ether cross-links. Phylogenetic and mutagenesis analyses reveal that the daropeptide maturases possess intrinsic multifunctionality, catalyzing not only the formation of ether cross-link but also C-C cross-linking and Ser oxidation. Intriguingly, the different chemical outcomes are controlled by the exact substrate motifs. Our work not only provides a roadmap for the discovery of new daropeptide natural products but also offers insights into the regulatory mechanisms that govern these remarkably versatile ether cross-link-forming rSAM enzymes.
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Affiliation(s)
- Suze Ma
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Wenhui Xi
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Shu Wang
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Heng Chen
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Sijia Guo
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Tianlu Mo
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Wenxue Chen
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Fener Chen
- Department of Chemistry, Fudan University, Shanghai 200433, China
- National Engineering Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, China
| | - Wei Ding
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qi Zhang
- Department of Chemistry, Fudan University, Shanghai 200433, China
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14
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Haysom SF, Machin J, Whitehouse JM, Horne JE, Fenn K, Ma Y, El Mkami H, Böhringer N, Schäberle TF, Ranson NA, Radford SE, Pliotas C. Darobactin B Stabilises a Lateral-Closed Conformation of the BAM Complex in E. coli Cells. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 135:e202218783. [PMID: 38515502 PMCID: PMC10952338 DOI: 10.1002/ange.202218783] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Indexed: 03/23/2024]
Abstract
The β-barrel assembly machinery (BAM complex) is essential for outer membrane protein (OMP) folding in Gram-negative bacteria, and represents a promising antimicrobial target. Several conformational states of BAM have been reported, but all have been obtained under conditions which lack the unique features and complexity of the outer membrane (OM). Here, we use Pulsed Electron-Electron Double Resonance (PELDOR, or DEER) spectroscopy distance measurements to interrogate the conformational ensemble of the BAM complex in E. coli cells. We show that BAM adopts a broad ensemble of conformations in the OM, while in the presence of the antibiotic darobactin B (DAR-B), BAM's conformational equilibrium shifts to a restricted ensemble consistent with the lateral closed state. Our in-cell PELDOR findings are supported by new cryoEM structures of BAM in the presence and absence of DAR-B. This work demonstrates the utility of PELDOR to map conformational changes in BAM within its native cellular environment.
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Affiliation(s)
- Samuel F. Haysom
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Jonathan Machin
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - James M. Whitehouse
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Jim E. Horne
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Katherine Fenn
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Yue Ma
- Astbury Centre for Structural Molecular BiologySchool of Biomedical SciencesUniversity of LeedsLeedsLS2 9JTUK
- School of Biological Sciences, Faculty of Biology, Medicine and HealthManchester Academic and Health Science CentreThe University of ManchesterManchesterM13 9PTUK
- Manchester Institute of BiotechnologyThe University of ManchesterManchesterM1 7DNUK
| | - Hassane El Mkami
- School of Physics and AstronomyUniversity of St. AndrewsSt. AndrewsKY16 9SSUK
| | - Nils Böhringer
- Institute for Insect BiotechnologyNatural Product ResearchJustus-Liebig-University GiessenOhlebergsweg 1235392GiessenGermany
- German Center for Infection Research (DZIF)Partner Site Giessen-Marburg-LangenOhlebergsweg 1235392GiessenGermany
| | - Till F. Schäberle
- Institute for Insect BiotechnologyNatural Product ResearchJustus-Liebig-University GiessenOhlebergsweg 1235392GiessenGermany
- German Center for Infection Research (DZIF)Partner Site Giessen-Marburg-LangenOhlebergsweg 1235392GiessenGermany
- Natural Product DepartmentFraunhofer-Institute for Molecular Biology and Applied Ecology (IME)Ohlebergsweg 1235392GiessenGermany
| | - Neil A. Ranson
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Sheena E. Radford
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Christos Pliotas
- Astbury Centre for Structural Molecular BiologySchool of Biomedical SciencesUniversity of LeedsLeedsLS2 9JTUK
- School of Biological Sciences, Faculty of Biology, Medicine and HealthManchester Academic and Health Science CentreThe University of ManchesterManchesterM13 9PTUK
- Manchester Institute of BiotechnologyThe University of ManchesterManchesterM1 7DNUK
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15
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Haysom SF, Machin J, Whitehouse JM, Horne JE, Fenn K, Ma Y, El Mkami H, Böhringer N, Schäberle TF, Ranson NA, Radford SE, Pliotas C. Darobactin B Stabilises a Lateral-Closed Conformation of the BAM Complex in E. coli Cells. Angew Chem Int Ed Engl 2023; 62:e202218783. [PMID: 37162386 PMCID: PMC10952311 DOI: 10.1002/anie.202218783] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 04/26/2023] [Accepted: 05/09/2023] [Indexed: 05/11/2023]
Abstract
The β-barrel assembly machinery (BAM complex) is essential for outer membrane protein (OMP) folding in Gram-negative bacteria, and represents a promising antimicrobial target. Several conformational states of BAM have been reported, but all have been obtained under conditions which lack the unique features and complexity of the outer membrane (OM). Here, we use Pulsed Electron-Electron Double Resonance (PELDOR, or DEER) spectroscopy distance measurements to interrogate the conformational ensemble of the BAM complex in E. coli cells. We show that BAM adopts a broad ensemble of conformations in the OM, while in the presence of the antibiotic darobactin B (DAR-B), BAM's conformational equilibrium shifts to a restricted ensemble consistent with the lateral closed state. Our in-cell PELDOR findings are supported by new cryoEM structures of BAM in the presence and absence of DAR-B. This work demonstrates the utility of PELDOR to map conformational changes in BAM within its native cellular environment.
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Affiliation(s)
- Samuel F. Haysom
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Jonathan Machin
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - James M. Whitehouse
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Jim E. Horne
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Katherine Fenn
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Yue Ma
- Astbury Centre for Structural Molecular BiologySchool of Biomedical SciencesUniversity of LeedsLeedsLS2 9JTUK
- School of Biological Sciences, Faculty of Biology, Medicine and HealthManchester Academic and Health Science CentreThe University of ManchesterManchesterM13 9PTUK
- Manchester Institute of BiotechnologyThe University of ManchesterManchesterM1 7DNUK
| | - Hassane El Mkami
- School of Physics and AstronomyUniversity of St. AndrewsSt. AndrewsKY16 9SSUK
| | - Nils Böhringer
- Institute for Insect BiotechnologyNatural Product ResearchJustus-Liebig-University GiessenOhlebergsweg 1235392GiessenGermany
- German Center for Infection Research (DZIF)Partner Site Giessen-Marburg-LangenOhlebergsweg 1235392GiessenGermany
| | - Till F. Schäberle
- Institute for Insect BiotechnologyNatural Product ResearchJustus-Liebig-University GiessenOhlebergsweg 1235392GiessenGermany
- German Center for Infection Research (DZIF)Partner Site Giessen-Marburg-LangenOhlebergsweg 1235392GiessenGermany
- Natural Product DepartmentFraunhofer-Institute for Molecular Biology and Applied Ecology (IME)Ohlebergsweg 1235392GiessenGermany
| | - Neil A. Ranson
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Sheena E. Radford
- Astbury Centre for Structural Molecular BiologySchool of Molecular and Cellular BiologyUniversity of LeedsLeedsLS2 9JTUK
| | - Christos Pliotas
- Astbury Centre for Structural Molecular BiologySchool of Biomedical SciencesUniversity of LeedsLeedsLS2 9JTUK
- School of Biological Sciences, Faculty of Biology, Medicine and HealthManchester Academic and Health Science CentreThe University of ManchesterManchesterM13 9PTUK
- Manchester Institute of BiotechnologyThe University of ManchesterManchesterM1 7DNUK
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16
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Zhong G, Wang ZJ, Yan F, Zhang Y, Huo L. Recent Advances in Discovery, Bioengineering, and Bioactivity-Evaluation of Ribosomally Synthesized and Post-translationally Modified Peptides. ACS BIO & MED CHEM AU 2023; 3:1-31. [PMID: 37101606 PMCID: PMC10125368 DOI: 10.1021/acsbiomedchemau.2c00062] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 04/28/2023]
Abstract
Ribosomally synthesized and post-translationally modified peptides (RiPPs) are of increasing interest in natural products as well as drug discovery. This empowers not only the unique chemical structures and topologies in natural products but also the excellent bioactivities such as antibacteria, antifungi, antiviruses, and so on. Advances in genomics, bioinformatics, and chemical analytics have promoted the exponential increase of RiPPs as well as the evaluation of biological activities thereof. Furthermore, benefiting from their relatively simple and conserved biosynthetic logic, RiPPs are prone to be engineered to obtain diverse analogues that exhibit distinct physiological activities and are difficult to synthesize. This Review aims to systematically address the variety of biological activities and/or the mode of mechanisms of novel RiPPs discovered in the past decade, albeit the characteristics of selective structures and biosynthetic mechanisms are briefly covered as well. Almost one-half of the cases are involved in anti-Gram-positive bacteria. Meanwhile, an increasing number of RiPPs related to anti-Gram-negative bacteria, antitumor, antivirus, etc., are also discussed in detail. Last but not least, we sum up some disciplines of the RiPPs' biological activities to guide genome mining as well as drug discovery and optimization in the future.
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Affiliation(s)
- Guannan Zhong
- Helmholtz
International Laboratory for Anti-Infectives, State Key Laboratory
of Microbial Technology, Shandong University, Qingdao 266237, China
- Suzhou
Research Institute, Shandong University, Suzhou, Jiangsu 215123, P. R. China
| | - Zong-Jie Wang
- Helmholtz
International Laboratory for Anti-Infectives, State Key Laboratory
of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Fu Yan
- Helmholtz
International Laboratory for Anti-Infectives, State Key Laboratory
of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Youming Zhang
- Helmholtz
International Laboratory for Anti-Infectives, State Key Laboratory
of Microbial Technology, Shandong University, Qingdao 266237, China
- CAS
Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute
of Synthetic Biology, Shenzhen Institute
of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- Faculty
of Synthetic Biology, Shenzhen Institute
of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Liujie Huo
- Helmholtz
International Laboratory for Anti-Infectives, State Key Laboratory
of Microbial Technology, Shandong University, Qingdao 266237, China
- Suzhou
Research Institute, Shandong University, Suzhou, Jiangsu 215123, P. R. China
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