Table I. Contour length and protein volumes of UvrB–DNA and UvrB*–DNA complexes.

	No. of molecules	Class I			Class II
		No. of molecules	Volume (kDa)	Wrap (nm)	No. of molecules	Volume (kDa)	Wrap (nm)
A. UvrB–DNA complexes
Washed with ATP
Wrapped	50	0/50 (0%)	–	–	50/50 (100%)	185 ± 26	25
Not wrapped	6	3/6 (50%)	n.d.a	0	3/6 (50%)	n.d.a	–
Washed without ATP
Wrapped	0	–	–	–	–	–	–
Not wrapped	115	45/115 (39%)	76.4 ± 11	0	70/115 (61%)	151 ± 28	0
Reintroduction of ATP
Wrapped	64	24/64 (37%)	87.4 ± 10	26	40/64 (63%)	168 ± 14	22
Not wrapped	0	–	–	–	–	–	–
B. UvrB*–DNA complexes
Washed with ATP
Wrapped	27	0/27 (0%)	–	–	27/27 (100%)	135 ± 18	23
Not wrapped	56	50/56 (89%)	61.7 ± 9	0	6/56 (11%)	n.d.a	0
Washed without ATP
Wrapped	0	–	–	–	–	–	–
Not wrapped	36	33/36 (92%)	61.7 ± 10	0	3/36 (8%)	n.d.a	0
Reintroduction of ATP
Wrapped	20	17/20 (85%)	77.1 ± 5	23	3/20 (15%)	161 ± 9	24
Not wrapped	51	43/51 (84%)	68.2 ± 8	0	8/51 (16%)	143 ± 6	0

All measured molecules were first divided in two groups; one group containing wrapped complexes, the other containing unwrapped complexes. Of both these, the protein volume and the amount of DNA involved in the wrapping were determined.

^aAmount of complexes too low to determine size accurately.