GST-Slt2-as thiophosphorylates recombinant GST-Rlm1.
A, expression of MLP1-lacZ, determined as β-galactosidase activity of cell extracts from co-transformants carrying the plasmid pMLP1-LacZ and pEG(KG)-SLT2 or pEG(KG)-slt2-as. Cells were grown in synthetic galactose medium at 24 °C in the absence (No addition) or presence of Congo red (30 μg/ml) and 20 μm of 2,3-DMB-PP1 when indicated for 4 h. Data shown represent the average of β-galactosidase activity of three independent transformants. Error bars indicate S.D. B, in vitro kinase assay using GST or GST-Slt2-as purified from Congo red-treated yeast cells and E. coli extracts containing GST or GST-Rlm1. Anti-thiophosphate (Anti-ThioP) ester antibodies (left panel) and anti-GST (right panel) were used to detect thiophosphorylated proteins and GST or GST-Rlm1, respectively.