Genetic and Functional Analyses of the DKxanthene Biosynthetic Gene Cluster from DSM 14675.

DKxanthenes are a class of yellow secondary metabolites produced by myxobacterial genera and . We identified a putative 49.5 kb DKxanthene biosynthetic gene cluster from DSM 14675 by genomic sequence and mutational analysis. The cluster was comprisedof 15 genes (MYSTI_06004-MYSTI_06018) encoding polyketide synthases, non-ribosomal peptide synthases, and proteins with unknown functions. Disruption of the genes by plasmid insertion resulted in defects in the production of yellow pigments. High-performance liquid chromatography and liquid chromatography-tandem mass spectrometry analysis indicated that the yellow pigments produced by DSM 14675 might be noble DKxanthene derivatives. did not require DKxanthenes for the formation of heat-resistant viable spores, unlike . Furthermore, DKxanthenes showed growth inhibitory activity against the fungi , , and .