Tyrosine kinase inhibitors are a new class of anticancer drugs, that are capable of directly interacting with the catalytic site of the target enzyme and thereby inhibiting catalysis. Therapeutically useful tyrosine kinase inhibitors are not specific for a single tyrosine kinase, but rather they are selective against a limited number of tyrosine kinases. The success of imatinib-mesylate (Gleeve...

Many investigators of tyrosine oxidation have used systems in vitro such as slices, minces, and, more recently, homogenates of liver. During our search for a suitable preparation other than liver slices for studying the conversion of phenylalanine to tyrosine, an extract of rat liver acetone powder was tested. Although the phenylalanine to tyrosine conversion was not demonstrated, it was found ...

The erythropoietin (Epo) receptor belongs to the cytokine receptor superfamily. Although the cytokine receptors do not possess a tyrosine kinase consensus sequence in the intracellular domain, rapid stimulation of a tyrosine kinase activity occurs after activation by the ligand. We and others have shown that Epo induces the tyrosine phosphorylation of its cognate receptor as well as phosphoryla...

In vitro studies demonstrate that the hydroxyl radical converts L-phenylalanine into m-tyrosine, an unnatural isomer of L-tyrosine. Quantification of m-tyrosine has been widely used as an index of oxidative damage in tissue proteins. However, the possibility that m-tyrosine might be generated oxidatively from free L-phenylalanine that could subsequently be incorporated into proteins as an L-tyr...

Phosphorylation of tyrosine residues by protein tyrosine kinases (PTK) and phosphotyrosine/Src homology 2 (SH2) domain interactions are crucial not only for signal transduction but also for regulation of PTK activity. Tyrosine residues also receive nitration and halogenation under oxidative conditions. It has been reported that nitration of tyrosine residue caused peptides to be a poor substrat...

Objective(s) Motility plays a major role in pathogenicity of Helicobacter pylori, yet there is  scarce data regarding its chemotactic behaviour. The present study was designed to investigate the chemotactic responses of local isolates of H. pylori towards various sugars, amino acids, as well as some other chemical substances. Materials and Methods Chemotaxis was assayed by a modified Adler’s...

Background: Uterine natural killer (uNK) cells are the most abundant leukocytes in pre-implantation endometrium and early pregnancy deciduas in humans and rodents. They are associated with structural changes in maternal spiral arteries but regulation of their re-cruitment and activation is incompletely understood. The major subpopulation of uNK cells in humans expresses CD56, the neural cell ad...

Abstract In this study, a four-enzyme cascade pathway was developed and reconstructed in vivo for the production of d - p -hydroxyphenylglycine (D-HPG), valuable intermediate used to produce ?-lactam antibiotics fine-chemical synthesis, from l -tyrosine. pathway, catalytic conversion 4-hydroxyphenylglyoxalate by meso -diaminopimelate dehydrogenase Corynebacterium glutamicum ( Cg DAPDH) identifi...