Brevinin-1Ma peptide

Brevinin-1Ma is a novel skin defense peptide from the endangered Sierra Nevada yellow-legged frog, R. sierrae. The expression of the peptide was significantly affected by treatment with probiotics, such that addition of a consortium of four anti-Bd bacteria led to the apparent relative reduction of the peptide. The composition of the peptide profile, but not the quantity of total peptides, was altered by the therapy.Brevinin-1Ma was tested against a range of amphibian skin cultures and found to inhibit growth of fungal pathogens Bd and B. salamandrivorans, but enhanced the growth of probiotic bacteria including Janthinobacterium lividum, Chryseobacterium ureilyticum, Serratia grimesii, and Pseudomonas sp. While commonly thought of as antimicrobial peptides, here brevinin-1Ma showed promicrobial function, facilitating microbial growth. Thus, skin exposure to probiotic bacterial cultures induced a shift in skin defense peptide profiles that appeared to act as an immune response functioning to regulate the microbiome. In addition to direct microbial antagonism, probiotic-host interactions may be a critical mechanism affecting disease resistance.