Isolation, Crystal and Solution Structure Determination, and Biosynthesis of Tubulysins—Powerful Inhibitors of Tubulin Polymerization from Myxobacteria

Myxobacteria have it both ways: Whereas the epothilones stabilize the tubulin cytoskeleton and build microtubuli, tubulysins, which have now been isolated from Archangium gephyra and Angiococcus disciformis, have exactly the opposite effect. They induce the disintegration of the microtubuli, and even picomolar concentrations can cause cell death by apoptosis. Their effect on cell cultures exceeds that of the most active epothilones by 50-fold.