Figure 1

FW-04-806 is identified as an Hsp90 binding medicine. (A) LC/MS spectrum detects the compound eluted from the Hsp90-loaded affinity column. Peak a and b represent elution samples from the control and FW-04-806 bound Hsp90-loaded column, respectively. MS spectrum displays M/z of Peak b. (B) Western blot confirms FW-04-806 binds to NBD of Hsp90. The “–” symbol represents no drug-loaded affinity column, the “+” symbol represents the drug-loaded affinity column. The test proteins are SKBR3 cell lysate, His-tagged yeast Hsp90, and His-tagged NBD, MD, CDD of yeast Hsp90. Human Hsp90 Antibody and His-probe antibody were used respectively. (C) Soluble FW-04-806 was added into SKBR3 cell lysate, His-tagged full-length, NBD, MD and CDD of yeast Hsp90 up to 10 μM before incubation with drug-loaded affinity resin. Picture a and c show Human Hsp90 Antibody; picture b and d show His-probe antibody. (D) Molecular structure of FW-04-806. (E) Geldanamycin (GA) binds to N-terminal Hsp90 (Protein Data Bank [PDB] ID 1YTE) in the ATP binding pocket. Hsp90 is shown in the green ribbon view; GA is shown in stick view. (F) FW-04-806 docks to N-terminal Hsp90 (PDB ID 2K5B). N-Hsp90 is shown in green ribbon view; FW-04-806 is shown in stick view. (G) FW-04-806 binds to the N-Hsp90/Cdc37 complex (PDB ID 1US7). N-Hsp90 is shown in green ribbon view; Cdc37 is shown in yellow ribbon view; FW-04-806 is shown in orange ball view. (H) Stick view of FW-04-806 bound to N-Hsp90/Cdc37 complex. N-Hsp90 is shown in green stick view; FW-04-806 is shown in white stick view; Cdc37 is shown in blue stick view. (I) Stick views of FW-04-806 and N-Hsp90 in white and green, respectively.