PMID: 28207984

Authors:

Prota AE, Bargsten K, Redondo M, Smith Iii AB, Yang CH, McDaid HM, Paterson I, Horwitz SB, Diaz JF, Steinmetz MO

Title:

Structural Basis of Microtubule Stabilization by Discodermolide.

Journal:

Chembiochem. 2017 Feb 16. doi: 10.1002/cbic.201600696.

Abstract:

Microtubule-stabilizing agents (MSAs) are widely used in chemotherapy. Here, using X-ray crystallography we describe the detailed binding modes of two potent MSAs, (+)-discodermolide (DDM) and the DDM-paclitaxel-hybrid KS-1-199-32, in the taxane pocket of ss-tubulin. Both compounds bind in a very similar hairpin conformation as previously observed in solution. However, they differentially stabilize the M-loop of ss-tubulin: KS-1-199-32 induces an M-loop helical conformation that is not observed for DDM. In the context of the microtubule structure, both MSAs connect the ss-tubulin helices H6 and H7 and loop S9-S10 with the M-loop, which is similar to the structural effects elicited by epothilone A, but distinct from paclitaxel. Together, our data rationalize a differential binding mechanism of DDM and KS-1-199-32 on tubulin.