Skip to main content
ARS Home » Midwest Area » Peoria, Illinois » National Center for Agricultural Utilization Research » Renewable Product Technology Research » Research » Publications at this Location » Publication #353397
Title: Anti-streptococcal liamocins from Aureobasidium pullulans

Author
item Leathers, Timothy
item MANITCHOTPISIT, PENNAPA - Former ARS Employee
item Price, Neil
item BISCHOFF, KENNETH - Former ARS Employee
item Skory, Christopher
item Rich, Joseph
item Nunnally, Melinda

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/12/2018
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Liamocins are a group of structurally related polyol lipids produced by certain strains of the polymorphic ascomycete Aureobasidium pullulans. Cultures produce a mixture of liamocin species depending on the strain and culture conditions. When grown on sugars, most strains produce liamocins composed of a single mannitol headgroup linked to either three or four 3,5-dihydroxydecanoic ester groups, which may be acetylated. Growth on polyols can produce liamocins with alternative headgroups. Liamocins act as biosurfactants and can inhibit certain cancer cell lines. Recently, it was discovered that liamocins exhibit antibacterial activity with specificity for Streptococcus species. Liamocins are active against all Streptococcus species tested thus far, including pathogenic species that cause mastitis in dairy cattle and swine diseases. Liamocins inhibit both planktonic and biofilm cultures of S. mutans and S. sobrinus, associated with dental caries. A variety of other human infections are caused by Streptococcus spp. Although highest yields have been reported from A. pullulans strains in phylogenetic clade 11, liamocins from this clade can be contaminated with olivaceous melanin. Therefore, a polyketide synthase knock-out derivative of clade 11 strain NRRL 50384 was constructed that produces melanin-free liamocins. Using this strain, an optimized medium was developed for production of liamocins, supporting yields of up to 22 g liamocins/L. Liamocins have potential as a useful new antimicrobial agent against Streptococcus species, particularly in prophylactic applications where a broad-spectrum antibiotic might be undesirable. This presentation is dedicated to the memory of our friend and colleague, Ken Bischoff.