Open AccessTyrosine phosphorylation of a cytoplasmic protein from the antarctic psychrotrophic bacterium Pseudomonas syringae
Author(s) -
Ray M.K,
Seshu Kumar G,
Shivaji S
Publication year - 1994
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1994.tb07142.x
Subject(s) - phosphorylation , tyrosine , protein tyrosine phosphatase , tyrosine phosphorylation , biochemistry , protein phosphorylation , western blot , pseudomonas syringae , biology , phosphatase , microbiology and biotechnology , chemistry , protein kinase a , gene
Cytoplasmic proteins from the antarctic psychrotrophic bacterium Pseudomonas syringae showed two phosphorylated proteins of molecular mass 66 kDa and 62 kDa. The phosphorylation of 66 kDa protein was enhanced in the presence of Triton X‐100 solubilised membrane proteins at a higher temperature (30°C) only. Western blot analysis and phosphoamino acid analysis indicated that the 66 kDa protein is phosphorylated at a tyrosine residue. Surprisingly, sodium orthovanadate, which is a known phosphotyrosine phosphatase (PTPase) inhibitor, inhibited the phosphorylation of the protein. The possible importance of this tyrosine phosphorylated protein to growth at low temperature is suggested.