Carbon monoxide carriers as antimicrobial drugs
Oeiras, 10.12.2015
In small amounts, carbon monoxide carriers can work as antibiotics. This is the main idea behind the latest paper from Lígia Saraiva and Carlos Romão Labs, who analysed the bactericidal activity of seven different carbon monoxide releasing molecules (CORMs) to establish a rationale for developing useful antibiotic drugs. The results are published in Dalton Transactions.
Carbon monoxide (CO) is toxic because it binds the blood haemoglobin, preventing oxygen transport in the body. So, regardless of the beneficial effects of this compound, inhaling gaseous CO is not an option. Fortunately, CORMs can be designed to bypass blood haemoglobin and safely deliver carbon monoxide into biological systems. However, this endeavor requires an extensive knowledge of the chemical traits and mechanisms of action behind CORM’s activity.
In this work, researchers analysed specific CORMs - transition metal carbonyl complexes – for their ability to deliver carbon monoxide and their effect in bacteria and in different types of eukaryotic cells (macrophages, kidney, liver, and epithelial cells). The seven CORMs under study differed in the transition metal, ancillary ligands, and CO release profile. Results suggest that selected CORMs may have relevant therapeutic potential as antimicrobial drugs, since they show opposite toxicity profiles towards bacteria and eukaryotic cells and their toxicity to eukaryotic cells can be made acceptably low. Furthermore, the activity of CORMs can be modulated through manipulation of the ancillary ligands.
By contributing to the understanding of the roots of the bactericidal action of CORMs, researchers hope to help establishing strategies for their development into a new class of antibiotics.
Original Article
Dalton Trans. (2015) DOI: 10.1039/C5DT02238J
Examining the antimicrobial activity and toxicity to animal cells of different types of CO-releasing molecules
Lígia S. Nobre, Hélia Jeremias, Carlos C. Romão, and Lígia M. Saraiva
