Ktedonoketone and 2 '-oxosattabacin, benzenoid metabolites from a thermophilic bacterium Thermosporothrix hazakensis in the phylum Chloroflexi

摘要

A thermophilic bacterium Thermosporothrix hazakensis NBRC 105916 which belongs to the class Ktedonobacteria was investigated to explore its biosynthetic potential of secondary metabolites. UV-guided fractionation led to the identification of a new benzenoid metabolite designated ktedonoketone (6) and an alpha-diketone metabolite 2'-oxosattabacin (7) along with five known compounds. Compound 7 was previously described as a synthetic compound, but this is the first finding as a natural product. Compound 7 induced adipocyte differentiation at 10-20 mu M and autophagy at 1-10 mu M. Compound 6 showed weak inducing activity of adipocyte differentiation. The biosynthetic origin of hazakacin (3), an acyloin-type compound, was elucidated by C-13-labeled precursor-feeding experiments.