FIG. 7.

Nucleotide binding to the catalytic domain of integrase. Integrase (IN) protein (lanes 1 to 3), the catalytic domain only (integrase residues 50 to 212; lanes 4 to 6), and the catalytic domain containing the F185K mutant (lanes 7 to 9) were incubated with [α-³²P]ATP and NaBH₃CN (lanes 1, 4, and 7), oxidized ATP (ox ATP) (lanes 2, 5, and 8), or oxidized ATP and NaBH₃CN (lanes 3, 6, and 9). In each case, Coomassie brilliant blue staining confirmed that the labeled band had the mobility of the integrase derivative studied (data not shown).