Table I. Statistics of three-dimensional reconstruction data.

	Motor concentration (mg/ml)	Motor concentration (µM) heads	No. of asymmetric units	Average phase residual
Ncd AMP-PNP	3.3	41	∼54 000	19.0
Ncd ADP	3.3	41	∼35 000	18.0
Ncd no-nucleotide	4.5/2.0	55/25	∼59 000	22.0
SH3–ncd no-nucleotide	4.4	42	∼44 000	19.1

The MT concentration was kept constant at 0.5 mg/ml, which corresponds to 5 µM αβ-tubulin dimers. Differing amounts of motor constructs were used in the experiments (columns 2 and 3). The number of asymmetric units (column 4) and the average phase residual in the final maps (column 5) are also shown.