• Microbiology and Biotechnology Letters
• /
• v.44 no.3
• /
• pp.391-399
• /
• 2016

Melithiazols are antifungal substances produced by the myxobacteria Melitangium lichenicola, Archangium gephyra, and Myxococcus stipitatus. Melithiazol biosynthetic genes have been identified in M. lichenicola, but not in A. gephyra and M. stipitatus until now. We identified a 37.3-kb melithiazol biosynthetic gene cluster from M. stipitatus DSM 14675 using genome sequence analysis and mutational analysis. The cluster is comprised of 9 genes (MYSTI_04973 to MYSTI_04965) that encode 4 polyketide synthase modules, 3 non-ribosomal peptide synthase modules, a putative fumarylacetoacetate hydrolase, a putative S-adenosylmethionine-dependent methyltransferase, and a putative nitrilase. Disruption of the MYSTI_04972 or MYSTI_04973 gene by plasmid insertion resulted in defective melithiazol production. The organization of the melithiazol biosynthetic modules encoded by 8 genes from MYSTI_04972 to MYSTI_04965 was similar to that in M. lichenicola Me l46. However, the loading module encoded by the first gene (MYSTI_04973) was different from that of M. lichenicola Me l46, explaining the difference in the production of melithiazol derivatives between the M. lichenicola Me l46 and M. stipitatus strains.

• Microbiology and Biotechnology Letters
• /
• v.42 no.4
• /
• pp.331-338
• /
• 2014

Myxococcus stipitatus KYC4013 extract exhibited the most potent antifungal activity among the extracts of 207 Myxococcus strains isolated in Korea. High-resolution LC-MS analysis revealed that M. stipitatus KYC4013 produces five antifungal substances and three other secondary metabolites that were predicted to be melithiazol and phenalamide derivatives, respectively. The putative melithiazol derivatives were best produced in CYS medium and the putative phenalamide derivatives were best produced in VY3 medium.