The Linkage Map of Streptomyces rimosus

Abstract

SUMMARY: Haploid recombinant selection has been used to map the loci of 24 auxotrophic mutations on a circular linkage group in an industrial strain of Streptomyces rimosus. The features of crosses are similar to those in S. coelicolor a 3 (2), except for the recovery of variable numbers of heterokaryons on selective media in S. rimosus crosses. By a suitable choice of selected marker combinations, heterokaryons can be largely eliminated. The linkage map of S. rimosus is extremely similar to that of S. coelicolor a 3 (2); this may indicate a conservation of gene arrangement in prokaryotes as already suggested by the similarity of linkage relationships in Escherichia coli and Salmonella typhimurium. The S. rimosus map provides further support for the idea of circular symmetry of the Streptomyces linkage map first proposed for S. coelicolor a 3 (2).