SSBP1

Single-stranded DNA binding proteins (SSBs) are essential for DNA replication, recombination, and repair processes in all organisms. Sulfolobus solfataricus, a hyperthermophilic archaeon, overexpresses its SSB (SsoSSB) to protect single-stranded DNA (ssDNA) during DNA metabolism .

Sulfolobus solfataricus is a species of extremophilic archaea that thrives in high-temperature environments, such as hot springs and hydrothermal vents. This organism can survive at temperatures as high as 80°C and at low pH levels, making it an ideal model for studying proteins that function under extreme conditions .

The SsoSSB protein has a unique structure that allows it to function effectively at high temperatures. It consists of a single OB (oligonucleotide/oligosaccharide-binding) fold coupled to a flexible C-terminal tail. The OB fold is responsible for binding to ssDNA, while the C-terminal tail mediates interactions with other proteins .

Studies have shown that the SsoSSB protein maintains its structural integrity and ssDNA binding ability even at elevated temperatures. The solution structure, backbone dynamics, and ssDNA binding properties of SsoSSB at 50°C have been characterized using NMR spectroscopy. The overall structure is consistent with those studied at room temperature, but certain regions, such as the loop between the first two β sheets, show differences in flexibility and conformation upon ssDNA binding .

The recombinant form of SsoSSB is typically expressed in Escherichia coli (E. coli) BL21 (DE3) cells. This allows for the production of large quantities of the protein for research purposes. The recombinant protein retains the same structural and functional properties as the native protein, making it a valuable tool for studying DNA metabolism in extreme environments .

The unique properties of SsoSSB make it a potential candidate for various biotechnological applications. Its ability to bind ssDNA at high temperatures could be utilized in PCR (polymerase chain reaction) and other DNA amplification techniques. Additionally, understanding the structural and dynamic properties of SsoSSB can provide insights into the behavior of proteins in thermophiles and guide the development of new experimental techniques .