Crystal structure of the calcium pump of sarcoplasmic reticulum at 2.6 A resolution

Nature. 2000 Jun 8;405(6787):647-55. doi: 10.1038/35015017.


Calcium ATPase is a member of the P-type ATPases that transport ions across the membrane against a concentration gradient. Here we have solved the crystal structure of the calcium ATPase of skeletal muscle sarcoplasmic reticulum (SERCA1a) at 2.6 A resolution with two calcium ions bound in the transmembrane domain, which comprises ten alpha-helices. The two calcium ions are located side by side and are surrounded by four transmembrane helices, two of which are unwound for efficient coordination geometry. The cytoplasmic region consists of three well separated domains, with the phosphorylation site in the central catalytic domain and the adenosine-binding site on another domain. The phosphorylation domain has the same fold as haloacid dehalogenase. Comparison with a low-resolution electron density map of the enzyme in the absence of calcium and with biochemical data suggests that large domain movements take place during active transport.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Binding Sites
  • Calcium / chemistry*
  • Calcium / metabolism
  • Calcium-Transporting ATPases / chemistry*
  • Crystallography, X-Ray
  • Cytoplasm / chemistry
  • Cytoplasm / enzymology
  • Hydrolysis
  • Models, Molecular
  • Protein Conformation
  • Protein Structure, Tertiary
  • Rabbits
  • Sarcoplasmic Reticulum / enzymology*


  • Adenosine Triphosphate
  • Calcium-Transporting ATPases
  • Calcium

Associated data

  • PDB/1EUL