The interaction of water molecules with purple membrane suspension using 2H double-quantum filter, 1H and 2H diffusion nuclear magnetic resonance.

摘要: Bacteriorhodopsin is a membrane protein of the purple (PM) Halobacterium salinarum, which isolated as sheets highly organized two-dimensional hexagonal microcrystals and for water molecules play crucial role that affects its function proton pump. In this paper we used single- double-quantum (2)H NMR well (1)H diffusion to characterize interaction with PM in D(2)O suspensions. We found that, under influence strong magnetic field on concentrated sample (0.61 mM), affect entire population residual quadrupolar splitting (upsilon(q) approximately 5.5 Hz, 298 K, at 11.7 T) observed molecules. coupling, creation time maximal DQF signal was obtained (tau(max)), relative intensity spectrum samples (referred herein order parameters) are very sensitive temperature, dilution, chemical modifications PM. D(2)O, these parameters seem reflect organization Interestingly, have some efficiency trimer packing, concluded from apo-membrane behavior. The data dionized blue membrane, partially delipidated sample, detergent-treated show parameters, dependent, structural integrity addition, revealed heating inside or outside magnet has, after cooling, different effect characteristics difference samples, were heated cooled presence absence field, corroborates conclusions above indirect reflections both microscopic macroscopic samples. measurements showed least three distinct populations could be identified, based their coefficients. These correlate previously reported system.