Defining specific lipid binding sites for a peripheral membrane protein in situ using subtesla field-cycling NMR.

ABSTRACT: Despite the profound physiological consequences associated with peripheral membrane protein localization, only a rudimentary understanding of the interactions of proteins with membrane surfaces exists because these questions are inaccessible by commonly used structural techniques. Here, we combine high resolution field-cycling (31)P NMR relaxation methods with spin-labeled proteins to delineate specific interactions of a bacterial phospholipase C with phospholipid vesicles. Unexpectedly, discrete binding sites for both a substrate analogue and a different phospholipid (phosphatidylcholine) known to activate the enzyme are observed. The lifetimes for the occupation of these sites (when the protein is anchored transiently to the membrane) are >1-2 micros (but <1 ms), which represents the fir

SUBMITTER: Pu M 

PROVIDER: S-EPMC2930691 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature