FIG. 6.

Effect of Zn²⁺ on recombinant HIV-1 IN full-site integration. HIV-1 INs coexpressed without protein chaperones (−ESL; purified by heparin-Sepharose) and with chaperones (+ESL; purified by SP-Sepharose) were tested for Zn²⁺ activation. The wt donor DNA (P-2) was used. Lanes 1 to 6, 25 μM Zn²⁺; lanes 8 to 13, no Zn²⁺. Control lanes 1 and 8, no IN; lanes 2 and 9, SIV IN at 25 nM; lanes 3 and 10 and 4 and 11, −ESL IN at 11 (lanes 3 and 10) and 22 nM (lanes 4 and 11); lanes 5 and 12 and 6 and 13, +ESL IN at 17 (lanes 5 and 12) and 34 nM (lanes 6 and 13). The half-site, full-site, and donor-to-donor products as well as the input donor are indicated on the left. The molecular mass markers (lane 7) are described in the legend for Fig. 3.