X-ray structure analysis of A17 type HIV-1 protease complexed with inhibitors

Adachi, Motoyasu; Arai, Shigeki; Tamada, Taro; Kuroki, Ryota; Hidaka, Koshi*; Kimura, Toru*; Kiso, Yoshiaki*

To obtain information for design of inhibitor against drug resistant mutant HIV protease, we determined X-ray crystal structures of A17 type HIV-1 protease complexed with inhibitors of lopinavir and KNI-1657. The gene of A17 type HIV-1 protease was synthesized chemically, and prepared using E. coli expression system. The results showed that affinity of lopinavir to the protease was 700 times lower than that of wild-type, and KNI-1657 has 20 times higher affinity to the protease than lopinavir. The crystals of complex were obtained using PEG4000 as precipitant. The diffraction data were collected at PF and SPring-8, and the structures were refined at R-factor of 19%.