Structure-function relationships of two paralogous single-stranded DNA-binding proteins from Streptomyces coelicolor: implication of SsbB in chromosome segregation during sporulation.

ABSTRACT: The linear chromosome of Streptomyces coelicolor contains two paralogous ssb genes, ssbA and ssbB. Following mutational analysis, we concluded that ssbA is essential, whereas ssbB plays a key role in chromosome segregation during sporulation. In the ssbB mutant, ∼30% of spores lacked DNA. The two ssb genes were expressed differently; in minimal medium, gene expression was prolonged for both genes and significantly upregulated for ssbB. The ssbA gene is transcribed as part of a polycistronic mRNA from two initiation sites, 163 bp and 75 bp upstream of the rpsF translational start codon. The ssbB gene is transcribed as a monocistronic mRNA, from an unusual promoter region, 73 bp upstream of the AUG codon. Distinctive DNA-binding affinities of single-stranded DNA-binding proteins monitored by

SUBMITTER: Paradzik T 

PROVIDER: S-EPMC3616714 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature