GSE104738
The compact genome in the clavulanic acid producing Streptomyces  strain unravels a variety of horizontal transfer reservoirs
Bacterial genomic plasticity and instability carry multiple functional genetic information in Streptomyces secondary metabolism. Our previously publication has reported an effective industrial Streptomyces strain, with a unique phenotype of the high clavulanic acid yield. The complete genome of strain F163-1 harboring a 136.9-kb giant region of plasticity (RGP) was sequenced. The chromosome and plasmid are densely packed by an exceptionally huge variety of potential secondary metabolic gene clusters, excluding production of putative antibiotics. Intriguingly, architecture and size differences of plasmid pSCL4 between F613-1 and ATCC 27064 suggest the pSCL4 plasmid evolving from pSCL4-like and pSCL2-like extrachromosomal replicons, in addition to the previously proposed ATCC 27064 mega-plasmid formation hypothesis through recombination between the smaller F613-1 pSCL4 plasmid arm regions and the linear chromosome. Comparative genomics systemically investigate secondary metabolism capacitates in this study indicates that frequent exchange of genetic materials between Streptomyces replicons may shape remarkable diversities of secondary metabolite repertoires. Consequently, the F613-1 strain seems to have evolved its specific genomic architectures and genetic patterns to meet the requirement in subsequent industrial processes. Overall design: mRNA profiles of S. clavuligerus F613-1 and ATCC27064 strains were generated by deep sequencing