FIGURE 3.

Nucleotide-binding pocket of Eg5·AMPPNP. a, waters W1 and W2 make extensive interactions with switch I residues Ser²³³ and Arg²³⁴ (yellow) and switch II residues Gly²⁶⁸ and Glu²⁷⁰ (green). Measured interatomic distances are shown. W1 is 3.3 Å from the γ-phosphorus atom. b, oxygen atoms of the nucleotide γ-phosphate are coordinated by Mg²⁺, switch I and switch II residues, and residues of the P-loop (pink).