SSB

The SBB, or single-stranded DNA binding protein (SSBP), is a crucial player in DNA replication, recombination, and repair processes. This protein safeguards single-stranded DNA by binding to it, thus preventing re-pairing into double-stranded DNA or degradation by nucleases. Unlike helicases, SSB lacks enzymatic activity and does not interact with ATP. In E. coli, SSB exists as a tetramer of 177 peptides, each binding to 32 nucleotides on single-stranded DNA. Its roles encompass maintaining the single-strand state, preventing intrachain secondary structures, protecting from nuclease hydrolysis, and enhancing the activity of certain enzymes. SSB is recyclable within cells, detaching from newly synthesized DNA chains to be reused, which is vital for genomic stability and the progression of DNA metabolic events.