6.16 : Single-Strand DNA Binding Proteins

For successful DNA replication, the unwinding of double-stranded DNA must be accompanied by stabilization and protection of the separated single strands of the DNA. This crucial task is performed by single-strand DNA-binding (SSB) proteins. They bind to the DNA in a sequence-independent manner, which means that the nitrogenous bases of the DNA need not be present in a specific order for binding of SSB proteins to it. The binding of SSB proteins straightens single-stranded DNA (ssDNA) and makes it rigid. This is believed to enhance DNA polymerase ability to correctly select bases, thereby increasing the fidelity of DNA replication.

The ever-growing threat of drug-resistant microorganisms demands the development of antibiotics with new targets. Due to their involvement in DNA replication, recombination, and repair, SSB proteins are being investigated for this purpose.