A common core for binding single‐stranded DNA: structural comparison of the single‐stranded DNA‐binding proteins (SSB) from E. coli and human mitochondria
1997; Wiley; Volume: 411; Issue: 2-3 Linguagem: Inglês
10.1016/s0014-5793(97)00747-3
ISSN1873-3468
AutoresGordon Webster, Jochen Genschel, Ute Curth, Claus Urbanke, ChulHee Kang, Rolf Hilgenfeld,
Tópico(s)DNA Repair Mechanisms
ResumoThe crystal structure of the DNA‐binding domain of E. coli SSB ( Eco SSB) has been determined to a resolution of 2.5 Å. This is the first reported structure of a prokaryotic SSB. The structure of the DNA‐binding domain of the E. coli protein is compared to that of the human mitochondrial SSB ( Hs mtSSB). In spite of the relatively low sequence identity between them, the two proteins display a high degree of structural similarity. Eco SSB crystallises with two dimers in the asymmetric unit, unlike Hs mtSSB which contains only a dimer. This is probably a consequence of the different polypeptide chain lengths in the Eco SSB heterotetramer. Crucial differences in the dimer‐dimer interface of Eco SSB may account for the inability of Eco SSB and Hs mtSSB to form cross‐species heterotetramers, in contrast to many bacterial SSBs.
Referência(s)