Tyrosylprotein Kinase

Protein tyrosine kinases Nonreceptor tyrosine kinases Cytoplasmic tyrosine kinases Tyrosylprotein kinase Hydroxyaryl-protein kinase... 

Protein sulfation occurs exclusively at tyrosine residues." It has been suggested that up to 1 % of the tyrosine protein content becomes sulfated, which is the most abundant posttranslational modification for tyrosine, with phosphorylation occurring only on 0.5% of tyrosine protein content." Sulfation occurs mostly on excreted proteins or trans-membrane proteins. Sulfation is catalyzed by tyrosylprotein sulfotransferase (TPST), with PAPS as a cosubstrate (Scheme 4). Like kinases, sulfotransferases have a biological inverse known as sulfatases." ... 

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