Linked Life Data

15924428

Source:http://linkedlifedata.com/resource/pubmed/id/15924428

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
2005-5-31
pubmed:abstractText
Twenty five amino acids within the "N", "P", and "A" domains of the Ca(2+) ATPase (SERCA1) headpiece were subjected to site directed mutagenesis, taking advantage of a high yield expression system. Functional and conformational effects of mutations were interpreted systematically in the light of the high resolution WT structure, defining direct involvement in catalysis as well as in stabilization of various positions acquired by each domain upon substrate binding and utilization. Amino acids involved in binding of ATP (such as Phe487 and Arg560 in the N domain) or phosphate (such as Asp351, Thr625, Lys684, and Thr353 in the P domain) were characterized with respect to their binding mechanism. Further identified were "positional" roles of several amino acids that stabilize neighboring residues for optimal binding of substrate or Mg(2+), or interface between headpiece domains as they change their relative positions in the course of the catalytic cycle. These include cross-linking of the "N" and "P" domains (e.g., Arg560/Asp627 salt bridge to stabilize domain approximation by ATP binding), and stabilization of the "A", "N", and activated "P" domains in arrangements differing from the ground E2 state and driven by catalytic events. This stabilization is produced through hydrogen bonds at domain interfaces, which vary depending on the intermediate state (e.g., Glu486/T171 in E1P and E2P, as opposed to Glu486/H190 in E2). We demonstrate that specific arrangements of the headpiece domains shown in crystal structures are, in fact, required to trigger displacement of transmembrane segments during the enzyme cycle in solution, allowing long range linkage of catalytic and Ca(2+) binding functions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8090-100
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:15924428-Adenosine Triphosphate, pubmed-meshheading:15924428-Amino Acid Substitution, pubmed-meshheading:15924428-Amino Acids, pubmed-meshheading:15924428-Animals, pubmed-meshheading:15924428-Binding Sites, pubmed-meshheading:15924428-COS Cells, pubmed-meshheading:15924428-Calcium-Transporting ATPases, pubmed-meshheading:15924428-Catalysis, pubmed-meshheading:15924428-Cercopithecus aethiops, pubmed-meshheading:15924428-Chickens, pubmed-meshheading:15924428-Crystallography, X-Ray, pubmed-meshheading:15924428-Enzyme Activation, pubmed-meshheading:15924428-Mutagenesis, Site-Directed, pubmed-meshheading:15924428-Phosphoproteins, pubmed-meshheading:15924428-Protein Structure, Tertiary, pubmed-meshheading:15924428-Rabbits, pubmed-meshheading:15924428-Sarcoplasmic Reticulum, pubmed-meshheading:15924428-Sarcoplasmic Reticulum Calcium-Transporting ATPases, pubmed-meshheading:15924428-Structure-Activity Relationship
pubmed:year
2005
pubmed:articleTitle
Functional and structural roles of critical amino acids within the"N", "P", and "A" domains of the Ca2+ ATPase (SERCA) headpiece.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, N.I.H., Extramural