[1][2] It is isolated from the fungus Rhizopus microsporus which causes rice seedling blight.

Rhizoxin is biosynthesised by Paraburkholderia rhizoxinica, a bacterial endosymbiont of the fungus Rhizopus microsporus.

[5] Rhizoxin binds beta tubulin in eukaryotic cells disrupting microtubule formation.

This, in turn, prevents formation of the mitotic spindle inhibiting cell division.

Related compounds to rhizoxin have improved biological activity (E.G Mertansine) .