Primary structure of the cAMP-dependent phosphorylation site of the plasma membrane calcium pump

Biochemistry. 1989 May 16;28(10):4253-8. doi: 10.1021/bi00436a020.


The primary structure of a region of the erythrocyte plasma membrane calcium pump which is phosphorylated by the cAMP-dependent protein kinase has been determined. The sequence is A-P-T-K-R-N-S-S(P)-P-P-P-S-P-D. The site is located between the calmodulin binding domain and the C-terminus of the ATPase. The ATPase is phosphorylated only at this site by the cAMP-dependent protein kinase, and the phosphorylation is inhibited by calmodulin. The effect of the phosphorylation is to decrease the Km for Ca2+ of the purified ATPase from about 10 microM to about 1.4 microM and to increase the Vmax of ATP hydrolysis about 2-fold.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Calcium Channels / metabolism*
  • Cell Membrane / metabolism*
  • Cyclic AMP / metabolism*
  • Erythrocyte Membrane / metabolism
  • Humans
  • In Vitro Techniques
  • Kinetics
  • Molecular Sequence Data
  • Molecular Structure
  • Phosphorylation


  • Calcium Channels
  • Cyclic AMP