High-affinity calcium-binding proteins in Escherichia coli.
Crude extracts of Escherichia coli contain at least three heat stable proteins of Mr, 33,000, 47,000, and 60,000, which bind 45Ca2+ in buffers containing micromolar calcium and physiological salt concentrations. Fractions containing these proteins neither activated the calmodulin-dependent enzyme, NAD kinase, nor inhibited the activity of this enzyme in the presence of brain calmodulin. Radioimmunoassay of crude extracts for calmodulin indicated the presence of a calmodulin-like antigen. Crude extracts also contain proteins that interact with 2-trifluoromethyl-10H-(3'-aminopropyl)phenothiazine-Sepharose in a calcium-dependent manner, but proteins eluted from this resin did not bind calcium with high affinity.
Harmon
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AC
Prasher
D
D
Cormier
M J
MJ
D002021:Buffers; D002135:Calcium-Binding Proteins / Q000032:analysis*; D002147:Calmodulin / Q000378:metabolism; D002850:Chromatography, Gel; D004533:Egtazic Acid; D004926:Escherichia coli / Q000032:analysis*; D008970:Molecular Weight; D010770:Phosphotransferases / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor)
D002021:Buffers; D002135:Calcium-Binding Proteins; D002147:Calmodulin; D004533:Egtazic Acid; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); C021844:NAD kinase