STUDY OF ROTATIONAL MOBILITY OF E(1) AND E(2) CA2+-ATPASE CONFORMERS IN SARCOPLASMIC-RETICULUM MEMBRANES USING TIME-RESOLVED PHOSPHORESCENCE ANISOTROPY DECAY MEASUREMENTSстатья
Информация о цитировании статьи получена из
Web of Science
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 27 мая 2015 г.
Аннотация:Membrane preparations of sarcoplasmic reticulum Ca2+-ATPase from rabbit skeletal muscles were covalently labeled with eosin 5'-isothiocyanate at Lys-515 in the putative active site and with 5-(iodoacetamido)eosin, probably at Cys-670 and Cys-674. These preparations were used for measurements of laser-flash induced phosphorescence anisotropy in the microsecond time scale. An analysis of the influence of diethyl ether, glycerol, the nonionic detergent C(12)E(9), and Ca2+-ATPase ligands, which stabilize the enzyme in the E(1) or E(2) conformeric state, on the anisotropy parameters have shown that Ca2+-ATPase in sarcoplasmic reticulum membranes is present both in monomeric and oligomeric states. Enzyme transition from E(1) to E(2) conformation is connected with an increase of oligomeric complex content and their average size. This supports the hypothesis that Ca2+-ATPase oligomeric state can be changed during reaction cycle of the enzyme.