CA2+ CALMODULIN-BINDING PROTEINS IN YEAST - CATABOLITE REPRESSION ANDINDUCTION BY CARBON-SOURCES/

Soluble calmodulin-binding proteins from Saccharomyces carlsbergensis were analyzed in cells grown on glucose, maltose and galactose as carb on source. A large number of polypeptide chains showed affinity for ca lmodulin by affinity chromatography and overlay techniques. Amongst th ese, polypeptides of 115, 67 and 45 kDa were only detected during the second exponential phase of growth on glucose or non-fermentative carb on sources, suggesting that they might be subjected to catabolite repr ession. Polypeptides of 195 and 22 kDa were only observed in cells gro wn on maltose, whereas 88 kDa polypeptide was only observed in galacto se-grown cells. Among the calmodulin -binding polypeptides, eight were phosphorylated in a Ca2+/calmodulin-dependent manner (220, 200, 175, 100, 62, 55, 31 and 16 kDa). Ca2+/calmodulin dependent [gamma-P-32] in corporation was dramatically decreased in yeast cells submitted to a h eat treatment.