  We introduce and parameterize a chemomechanical model of microtubule dynamics
on the dimer level, which is based on the allosteric tubulin model and includes
attachment, detachment and hydrolysis of tubulin dimers as well as stretching
of lateral bonds, bending at longitudinal junctions, and the possibility of
lateral bond rupture and formation. The model is computationally efficient such
that we reach sufficiently long simulation times to observe repeated
catastrophe and rescue events at realistic tubulin concentrations and
hydrolysis rates, which allows us to deduce catastrophe and rescue rates. The
chemomechanical model also allows us to gain insight into microscopic features
of the GTP-tubulin cap structure and microscopic structural features triggering
microtubule catastrophes and rescues. Dilution simulations show qualitative
agreement with experiments. We also explore the consequences of a possible
feedback of mechanical forces onto the hydrolysis process and the GTP-tubulin
cap structure.
