Di Primo C, Sligar S G, Hoa G H, Douzou P
INSERM-INRA U310, Institut de Biologie Physico-Chimique, Paris, France.
FEBS Lett. 1992 Nov 9;312(2-3):252-4. doi: 10.1016/0014-5793(92)80946-e.
The rates of NADH oxidation during the hydroxylation of camphor by cytochrome P-450cam were followed in the presence of co-solvents used to increase the osmotic pressure surrounding the protein-bound water. As a result, the measured Vmax decreases independently of the perturbant tested. Roughly 28 molecules of water, involved during the catalytic cycle, are deduced from the variation of Vmax as a function of osmotic pressure. These molecules, in part, could be those present in the cytochrome P-450cam-putidaredoxin interface.
