Identification of a new phosphorylation site in cardiac muscle phosphofructokinase.
The novel phosphorylation site (Ser376) that we discovered during in vitro studies of the troponin C- or calmodulin-induced phosphorylation of rabbit muscle phosphofructokinase [Zhao, Z., Malencik, D.A., and Anderson, S. R. (1991) Biochemistry 30, 2204] also undergoes phosphorylation in the epinephrine-stimulated rabbit heart. Reversed-phase HPLC and/or iron chelate affinity chromatography performed on CNBr digests of phosphofructokinase that had been isolated from epinephrine-treated hearts yields a largely phosphorylated peptide corresponding to amino acid residues 371-378 of the enzyme. Mass spectrometry, gas phase sequencing, and amino acid analyses establish the structure and phosphorylation state of the peptide.
Harrahy
J J
JJ
Department of Biochemistry and Biophysics, Oregon State University, Corvallis 97331, USA.
Malencik
D A
DA
Zhao
Z
Z
Hisaw
F L
FL
Anderson
S R
SR
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D009206:Myocardium / Q000201:enzymology*; D010449:Peptide Mapping; D010732:Phosphofructokinase-1 / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation; D011817:Rabbits; D012694:Serine / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D012694:Serine; D010732:Phosphofructokinase-1