title: Ultrashort antibacterial and antifungal lipopeptides.
abstract: Host-defense cationic antimicrobial peptides ( approximately 12-50 aa long) play an essential protective role in the innate immune system of all organisms. Lipopeptides, however, are produced only in bacteria and fungi during cultivation, and they are composed of specific lipophilic moieties attached to anionic peptides (six to seven amino acids). Here we report the following. (i) The attachment of an aliphatic chain to otherwise inert, cationic D,L tetrapeptides endows them with potent activity against various microorganisms including antibiotic resistance strains. (ii) Cell specificity is determined by the sequence of the short peptidic chain and the length of the aliphatic moiety. (iii) Despite the fact that the peptidic chains are very short, their mode of action involves permeation and disintegration of membranes, similar to that of many long antimicrobial peptides. Besides adding important information on the parameters necessary for host-defense lipopeptides to kill microorganisms, the simple composition of these lipopeptides and their diverse specificities should make them economically available, innate immunity-mimicking antimicrobial and antifungal compounds for various applications.
authors.affiliation: Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Arik
authors.initials: A
authors.lastname: Makovitzki
authors.forename: Dorit
authors.initials: D
authors.lastname: Avrahami
authors.forename: Yechiel
authors.initials: Y
authors.lastname: Shai
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D000935:Antifungal Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects / Q000648:ultrastructure; D002463:Cell Membrane Permeability / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects / Q000648:ultrastructure; D008074:Lipoproteins / Q000737:chemistry* / Q000494:pharmacology*; D046529:Microscopy, Electron, Transmission; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000648:ultrastructure
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D008074:Lipoproteins; D010455:Peptides