A study by Banerjee and Bagchi about the non-bulklike role of water in insulin dimerization has been accepted in PNAS. The authors report the following about the significance of their study –

“Despite its paramount importance, a microscopic characterization of protein association/dissociation has remained a non-trivial challenge. We have carried out atomistic simulation (biased and unbiased) to characterize insulin dimerization and dissociation process fully with a special attention to the role of water. Insulin is our system of interest because its monomer is the biologically active species but it remains in the inactive hexameric and dimeric storage forms. Our study reveals that at larger separation of two monomers (RMM ∼ 5 nm), dynamical properties of water molecules confined between them exhibit considerable deviation from bulklike characteristics, although structure remains bulklike. Analysis of both the large-scale water density fluctuation and protein conformational changes allows us to provide a complete picture of protein dissociation–association mechanism.”