{"title":"Synthesis and antibacterial properties under blue LED light of conjugates between the siderophore desferrioxamine B (DFOB) and an Iridium(III) complex","authors":"","doi":"10.1016/j.bmc.2024.117842","DOIUrl":null,"url":null,"abstract":"<div><p>The decline of antibiotics efficacy worldwide has recently reached a critical point urging for the development of new strategies to regain upper hand on multidrug resistant bacterial strains. In this context, the raise of photodynamic therapy (PDT), initially based on organic photosensitizers (PS) and more recently on organometallic PS, offers promising perspectives. Many PS exert their biological effects through the generation of reactive oxygen species (ROS) able to freely diffuse into and to kill surrounding bacteria. Hijacking of the bacterial iron-uptake systems with siderophore-PS conjugates would specifically target pathogens. Here, we report the synthesis of unprecedented conjugates between the siderophore desferrioxamine B (DFOB) and an antibacterial iridium(III) PS. Redox properties of the new conjugates have been determined at excited states and compared to that of an antibacterial iridium PS previously reported by our groups. Tested on nosocomial pathogen <em>Pseudomonas aeruginosa</em> and other bacteria, these conjugates demonstrated significant inhibitory activity when activated with blue LED light. Ir(III) conjugate and iridium free DFOB-2,2′-dipyridylamine ligands were crystallized in complex with FoxA, the outer membrane transporter involved in DFOB uptake in <em>P. aeruginosa</em> and revealed details of the binding mode of these unprecedented conjugates.</p></div>","PeriodicalId":255,"journal":{"name":"Bioorganic & Medicinal Chemistry","volume":null,"pages":null},"PeriodicalIF":3.3000,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0968089624002566/pdfft?md5=1e00832bf69aa3f3a83d7fe3f662ab0e&pid=1-s2.0-S0968089624002566-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Bioorganic & Medicinal Chemistry","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0968089624002566","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The decline of antibiotics efficacy worldwide has recently reached a critical point urging for the development of new strategies to regain upper hand on multidrug resistant bacterial strains. In this context, the raise of photodynamic therapy (PDT), initially based on organic photosensitizers (PS) and more recently on organometallic PS, offers promising perspectives. Many PS exert their biological effects through the generation of reactive oxygen species (ROS) able to freely diffuse into and to kill surrounding bacteria. Hijacking of the bacterial iron-uptake systems with siderophore-PS conjugates would specifically target pathogens. Here, we report the synthesis of unprecedented conjugates between the siderophore desferrioxamine B (DFOB) and an antibacterial iridium(III) PS. Redox properties of the new conjugates have been determined at excited states and compared to that of an antibacterial iridium PS previously reported by our groups. Tested on nosocomial pathogen Pseudomonas aeruginosa and other bacteria, these conjugates demonstrated significant inhibitory activity when activated with blue LED light. Ir(III) conjugate and iridium free DFOB-2,2′-dipyridylamine ligands were crystallized in complex with FoxA, the outer membrane transporter involved in DFOB uptake in P. aeruginosa and revealed details of the binding mode of these unprecedented conjugates.
期刊介绍:
Bioorganic & Medicinal Chemistry provides an international forum for the publication of full original research papers and critical reviews on molecular interactions in key biological targets such as receptors, channels, enzymes, nucleotides, lipids and saccharides.
The aim of the journal is to promote a better understanding at the molecular level of life processes, and living organisms, as well as the interaction of these with chemical agents. A special feature will be that colour illustrations will be reproduced at no charge to the author, provided that the Editor agrees that colour is essential to the information content of the illustration in question.