  Combining simulations and theory I study the interplay between bundle elastic
degrees of freedom and crosslink binding propensity. By slowly driving bundles
into a deformed configuration, and depending on the mechanical stiffness of the
crosslinking agent, the binding affinity is shown to display a sudden and
discontinuous drop. This indicates a cooperative unbinding process that
involves the crossing of a free-energy barrier. Choosing the proper
crosslinker, therefore, not only allows to change the composite elastic
properties of the bundle, but also the relevant time-scales, which can be tuned
from the single-crosslink binding rate to the much longer escape time over the
free-energy barrier.
