... and the seven conserved DNA-dependent ATPase motifs (I, IA and II toVI). The five CSB fragments cover amino acids 2–3 41, 31 0–5 20, 46 5–1 056, 95 3–1 204, and 118 7–1 493 of CSB, respectively. (B) The ... 430 6–4 314 ª 2005 FEBSglutaraldehyde of the CSB dimer showed that CSBexists as a dimer in solution and indicated that the dimer forms in the absence of DNA and ATP. In fur-ther support of CSB ... in CSB and thus supports the possibility of CSB dimerizationthrough the ATPase domain.In the case of helicases, dimerization is of clearbenefit for the processivity of the helicase reaction,such...