Antibacterial liamocins with alternative carbohydrate headgroups

Authors: Leathers, Timothy; Price, Neil; Skory, Christopher - Chris

Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 8/20/2017
Publication Date: 8/20/2017
Citation: Leathers, T.D., Price, N.P., Skory, C.D. 2017. Antibacterial liamocins with alternative carbohydrate headgroups [abstract]. American Chemical Society National Meeting, August 20-24, 2017, Washington, D.C. No. 2736606.

Interpretive Summary:

Technical Abstract: Liamocins are unique polyol lipids with biosurfactant, anticancer, and antibacterial properties, produced by certain strains of the fungus Aureobasidium pullulans. Liamocins have potential agricultural and pharmaceutical applications as antibacterials with specificity against Streptococcus sp. There are four principle types of liamocins, consisting of a single polyol headgroup partially O-acylated with polyester tails containing three or four 3,5-dihydroxydecanoic ester groups, some of which are acetylated. Highest yields have been obtained from strains in phylogenetic clade 11, such as NRRL 50384. Naturally occurring strains produce liamocins with mannitol headgroups, regardless of the carbohydrate growth substrates. A. pullulans strain NRRL 50384 was genetically modified by deletion of both the mannitol 1-phosphate dehydrogenase and mannitol dehydrogenase genes. This modified strain was unable to synthesize mannitol de novo, and produced liamocins with a variety of alternative carbohydrate headgroups, depending on the carbohydrate growth substrate. The new liamocins were characterized by MALDI-MS, GC-MS, and NMR. Structural variety can thus be introduced and controlled in liamocin carbohydrate headgroups, creating new types of antimicrobials with potentially modified activities and applications.