Enzymes PTPase

An interesting facet of the molecular modelling studies [66] was that they suggested that one methyl group of the hydroxylamine ligand was in an orientation suitable for replacement by other functionality. This is potentially important because PTPase active site residues are highly conserved, and enzyme selectivity is conferred... 

As a model system, Yop51 PTPase15 was analyzed. Deprotonated PTPases act as nucleophilic thiolates during attacks on phosphates. MS analyses of PTPases are possible due to the predictable formation of a covalent phos-phoenzyme intermediate.12 In this study, unphosphorylated enzyme is used as an internal standard to permit quantitation of the phosphorylated to unphosphorylated enzyme ratio, used to determine pre-steady state kinetic values. 

Protein tyrosine phosphatases (PTPases) are an important class of enzymes for the regulation of signal transduction pathways that control a number of cellular processes including cell growth and differentiation. The phosphorylation of tyrosyl protein residues has been shown to be one of the key events involved in intracellular signaling for selective gene activation. The PTPases have been shown to work in concert with... 

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