Interactions between curcumin derivatives C085 and various constructs of Hsp90 and effects of C085 on Hsp90 ATPase activity / 中国药理学通报

ABSTRACT

Aim To estimate the affinity between C085 and Hsp90 and the inhibitory effects of C085 on the activity of Hsp90 ATPase. Methods The fluores-cence spectrum experiment was applied to examine the affinity between different C085 concentrations and Hsp90 , NHsp90 , MHsp90 , CHsp90; fluorescence in-tensities were recorded in the range of 290-510 nm at 293 K, 303 K and 310 K, respectively;a colorimetric assay for inorganic phosphate based on the formation of a phosphomolybdate complex and subsequent reaction with malachite green was used to examine the inhibitory effects of C085 on the activity of Hsp90 ATPase. Re-sults The dissociation constant KD value of C085 was (11. 163 ± 0. 316 ) μmol · L-1 . The interaction be-tween C085 and Hsp90 was driven mainly by electro-static interaction. C085 showed strongest affinity with CHsp90. When the concentration of ATP was 1 mmol· L-1 ,the inhibition of Hsp90 ATPase activity of C085 with the IC50 value was 6. 04μmol·L-1 . Conclusions The interaction mechanism between C085 and Hsp90 can be analyzed by fluorescence spectrum. C085 shows strong inhibition ATPase activity of Hsp90 .