DEVELOPMENT OF A GENE CLONING SYSTEM FOR STREPTOMYCES-HYGROSCOPICUS SUBSP YINGCHENGENSIS, A PRODUCER OF 3 USEFUL ANTIFUNGAL COMPOUNDS, BY ELIMINATION OF 3 BARRIERS TO DNA TRANSFER

Streptomyces hygroscopicus 10-22 could not be transformed with any of the commonly used Streptomyces plasmid vectors and was resistant to pl aque formation by the Streptomyces phages phiC31 and R4. Repeated sele ction resulted in the isolation of derivatives of S. hygroscopicus 10- 22 that could be transformed with pIJ101- and pJV1-derived cloning vec tors and of restriction-deficient derivatives that could accept DNA pr opagated in Streptomyces lividans 66. These new strains, which include three that still produce the original antibiotics, can be used as hos ts for gene cloning. Insertion of nonreplicating vectors hy homologous recombination and transposition of Tn4560 were demonstrated in S. hyg roscopicus 10-22.