Premium
Identification of the phosphorylation sites in elongation factor‐2 from rabbit reticulocytes
Author(s) -
Price Nigel T.,
Redpath Nicholas T.,
Severinov Konstantin V.,
Campbell David G.,
Russell J.M.,
Proud Christopher G.
Publication year - 1991
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(91)80489-p
Subject(s) - phosphorylation , threonine , reticulocyte , elongation factor , biochemistry , kinase , calmodulin , protein kinase a , chemistry , protein phosphorylation , microbiology and biotechnology , elongation , biology , serine , enzyme , rna , gene , ribosome , materials science , ultimate tensile strength , metallurgy
The sites in eukaryotic elongation factor eEF‐2 phosphorylated by the Ca 2+ /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‐Thr 14 ‐Asp‐Thr 18 ‐Arg. The same sites are labelled in eEF‐2 isolated from reticulocyte lysates.