Identification of peptaibols as specific inhibitors of the futalosine pathway.

Menaquinone is an indispensable cofactor in the electron-transfer pathway for most Gram-positive bacteria. While most bacteria biosynthesize menaquinone by the well-known canonical pathway, some bacteria including Helicobacter pylori, which is a pathogen causing stomach cancer, use the futalosine pathway. Because beneficial intestinal bacteria such as lactobacilli use the canonical pathway, the futalosine pathway will be a great target for developing antibiotics specific to H. pylori. In this study, we searched for such metabolites from actinomycetes and fungi and identified 4 new peptaibols from culture broth of Verruciconidia sp. FKI-8918 as specific inhibitors of the futalosine pathway.