898 HUNTER & COOPER cleotides had set a precedent, reports of orthophosphate
esterified to tyrosine did not emerge until 1979 (1). Phosphotyrosine (P. Tyr) was first …

Unrestricted protein tyrosine phosphatase (PTPase) activity may play a role in pathogenesis.
For instance, the virulence determinant gene, yopH, of Yersinia pseudotuberculosis …

Protein phosphorylation has been shown to occur in over fifty different bacterial species and,
therefore, seems to be a universal device among prokaryotes. Most of the protein kinases …

Protein kinases play central roles in the regulation of eukaryotic and prokaryotic cell growth,
division, and differentiation. The Caulobacter crescentus divL gene encodes a novel …

The phosphorylation of proteins at tyrosine residues is known to play a key role in the control
of numerous fundamental processes in animal systems. In contrast, the biological …

Phosphorylation and dephosphorylation of proteins catalyzed by protein kinases and protein
phosphatases are recognized as major processes for regulating cellular functions. First …

The protein tyrosine phosphatases comprise a family of enzymes that specifically
dephosphorylate tyrosyl residues. Determination of the amino acid sequence of a major low …

Protein phosphorylation on serine, threonine and tyrosine is established as an important
regulatory modification in bacteria. A growing number of studies employing mass …

Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School,
andThe Dana Farber Cancer Institute, Boston, Massachusetts 02115, and Central Research …

Mitogen-activated protein (MAP) kinase pathways include a three-kinase cascade
terminating in a MAP kinase family member. The middle kinase in the cascade is a …