  Cooperative binding affects many processes in biology, but it is commonly
addressed only in equilibrium. In this work we explore dynamical cooperativity
in driven systems, where the cooperation occurs because some of the bonds
change the dynamical response of the system to a regime where the other bonds
become active. To investigate such cooperativity we study the frictional
binding between two flow driven surfaces that interact through a large
population of activated bonds. In particular, we study systems where each bond
can have two different modes: one mode corresponds to a fast forming yet weak
bond, and the other is a strong yet slow forming bond. We find considerable
cooperativity between both types of bonds. Under some conditions the system
behaves as if there were only one binding mode, corresponding to a strong and
fast forming bond. Our results may have important implications on the friction
and adhesion between sliding surfaces containing complementary binding motifs,
such as in the case of cells binding to the vessel walls under strong flowing
conditions.
