Prodigiosin, Violacein, and Volatile Organic Compounds Produced by Widespread Cutaneous Bacteria of Amphibians Can Inhibit Two Batrachochytrium Fungal Pathogens.

Symbiotic bacteria can produce secondary metabolites and volatile compounds that contribute to amphibian skin defense. Some of these symbionts have been used as probiotics to treat or prevent the emerging disease chytridiomycosis. We examined 20 amphibian cutaneous bacteria for the production of prodigiosin or violacein, brightly colored defense compounds that pigment the bacteria and have characteristic spectroscopic properties making them readily detectable, and evaluated the antifungal activity of these compounds.

The antimicrobial activity of mono-, bis-, tris-, and tetracationic amphiphiles derived from simple polyamine platforms.

A series of 34 amphiphilic compounds varying in both number of quaternary ammonium groups and length of alkyl chains has been assembled. The synthetic preparations for these structures are simple and generally high-yielding, proceeding in 1-2 steps without the need for chromatography. Antibacterial MIC data for these compounds were determined, and over half boast single digit MIC values against a series of gram-positive and gram-negative bacteria.