A new model of the tautomycin–PP1 complex that is not analogous to the corresponding okadaic acid structure

A revised model of PP1–tautomycin (TM) complex suggests that this toxin does not bind in a conformation analogous to its structural cousin okadaic acid (OA), as has been assumed, but instead more resembles the mode of binding adopted by calyculin. This model rationalizes the unexpected potency of a truncated TM analogue lacking the bicyclic ketal common to TM and OA.