Evolution of the terminal regions of the Streptomyces linear chromosome.

Comparative analysis of the Streptomyces chromosome sequences, between Streptomyces coelicolor, Streptomyces avermitilis, and Streptomyces ambofaciens ATCC23877 (whose partial sequence is released in this study), revealed a highly compartmentalized genetic organization of their genome. Indeed, despite the presence of specific genomic islands, the central part of the chromosome appears highly syntenic. In contrast, the chromosome of each species exhibits large species-specific terminal regions (from 753 to 1,393 kb), even when considering closely related species (S.

Intraspecific variability of the terminal inverted repeats of the linear chromosome of Streptomyces ambofaciens.

The sequences of the terminal inverted repeats (TIRs) ending the linear chromosomal DNA of two Streptomyces ambofaciens strains, ATCC23877 and DSM40697 (198 kb and 213 kb, respectively), were determined from two sets of recombinant cosmids. Among the 215 coding DNA sequences (CDSs) predicted in the TIRs of strain DSM40697, 65 are absent in the TIRs of strain ATCC23877. Reciprocally, 45 of the 194 predicted CDSs are specific to the ATCC23877 strain.