1d1o
COOPERATIVITY IN EF-HAND CA2+-BINDING PROTEINS: EVIDENCE OF SITE-SITE COMMUNICATION FROM BINDING-INDUCED CHANGES IN STRUCTURE AND DYNAMICS OF N56A CALBINDIN D9K
OverviewOverview
The cooperative binding of Ca2+ ions is an essential functional property of the EF-hand family of Ca2+-binding proteins. To understand how these proteins function, it is essential to characterize intermediate binding states in addition to the apo- and holo-proteins. The three-dimensional solution structure and fast time scale internal motional dynamics of the backbone have been determined for the half-saturated state of the N56A mutant of calbindin D9k with Ca2+ bound only in the N-terminal site. The extent of conformational reorganization and a loss of flexibility in the C-terminal EF-hand upon binding of an ion in the N-terminal EF-hand provide clear evidence of the importance of site-site interactions in this family of proteins, and demonstrates the strength of long-range effects in the cooperative EF-hand Ca2+-binding domain.
About this StructureAbout this Structure
1D1O is a Single protein structure of sequence from Bos taurus. Full crystallographic information is available from OCA.
ReferenceReference
Site-site communication in the EF-hand Ca2+-binding protein calbindin D9k., Maler L, Blankenship J, Rance M, Chazin WJ, Nat Struct Biol. 2000 Mar;7(3):245-50. PMID:10700285 Page seeded by OCA on Fri May 2 13:20:55 2008