X-ray structure analysis of the single-chain derivatives of HIV-1 protease in complex with inhibitor

Adachi, Motoyasu; Hatanaka, Takaaki*; Ito, Yuji*; Hidaka, Koshi*; Tsuda, Yuko*; Kiso, Yoshiaki*; Kuroki, Ryota

HIV protease is known as a drug target protein. It is important to clear relationship between structural data and kinetic and physicochemical parameters for drug design. We prepared single-chained enzyme linked by two amino acids and cross-liked enzyme bridged by disulfide bond. The two single-chained enzymes were expressed as inclusion body and refolded by dilution method. The purified enzyme complexed with inhibitor KNI-272 was crystallized, and solved the crystal structures. The designed sc- and cl-HIV-PR will be useful for evaluate the affinity of newly designed inhibitors from kinetic and thermodynamic point of view. Finally, we also report the results of analysis in affinity of inhibitors by surface plasmon resonance.