Identification of the phosphorylation sites in elongation factor-2 from rabbit reticulocytes.
The sites in eukaryotic elongation factor eEF-2 phosphorylated by the Ca2+/calmodulin-dependent eEF-2 kinase in vitro have been identified. The kinase catalysed the rapid incorporation of one mol of phosphate per mol eEF-2 and the slower incorporation of a second mol. All the phosphorylation sites in eEF-2 are contained in the CNBr fragment corresponding to residues 22-155. Tryptic digestion of phosphorylated eEF-2 yielded 3 phosphopeptides, one being unique to monophosphorylated eEF-2. The phosphorylation sites were identified as threonine residues 56 and 58, the former being more rapidly phosphorylated. Ala-Gly-Glu-Thr-Phe-Thr56-Asp-Thr58-Arg. The same sites are labelled in eEF-2 isolated from reticulocyte lysates.
Price
N T
NT
Department of Biochemistry, School of Medical Sciences, University of Bristol, UK.
Redpath
N T
NT
Severinov
K V
KV
Campbell
D G
DG
Russell
J M
JM
Proud
C G
CG
D000595:Amino Acid Sequence; D000818:Animals; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors / Q000737:chemistry / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry; D010449:Peptide Mapping; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism; D010766:Phosphorylation; D011817:Rabbits; D012156:Reticulocytes / Q000378:metabolism*; D013997:Time Factors
D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors; D010446:Peptide Fragments; D010750:Phosphoproteins