The genomic DNA of Streptoverticillium sp. 3-7, which produces UK-2, was analyzed to identify a region expected to be a UK-2 biosynthetic gene cluster. Moreover, by colony hybridization, DNAs in the region were successfully isolated. Further, the DNAs were used to prepare a strain in which the genes present in the region were disrupted. The strain was found not to produce UK-2. It was verified that the genomic region was the UK-2 biosynthetic gene cluster. Furthermore, Streptoverticillium sp. 3-7 was transformed by introduction of a vector in which the isolated UK-2 biosynthetic gene cluster was inserted. It was also found out that the UK-2 productivity by the transformant was improved about 10 to 60 times or more in comparison with that of the parental strain. Moreover, it was revealed that 2 copies of the UK-2 biosynthetic gene cluster were present per cell in these transformants, respectively.
