TABLE 5.

Effects of mutagenic alteration of serine residues in the putative activation loop on the activity of rSsoPK2^a

Mutational alteration(s)	Mutagenic oligonucleotide	Casein phosphorylation	Autophosphorylation
Ser538Ala, Ser539Ala	5′-CTAAAGTTGTTAGCGGCTGCCAGAGAGATA-3′	+	+
Ser548Ala	5′-CAAAATGAGGAGGCTTATAAGCTTGTGAAG-3′	+	−
Ser554Ala	5′-GAGTTATAAGCTTGTGAAGGCCTATATAATAAAATACAGC-3′	+	+
Ser560Ala	5′-GTGAAGAGCTATATAATAAAATACGCCTTAAAACCCGAAG-3′	+	+

^a+, phosphorylation observed; −, phosphorylation not observed.