Binding site homology, enzyme inhibitors

The metallobiochemistry of this molecule has been explored in some detail. Ba " and Zn bind and act as competitive inhibitors. The presence of Mg " " does not affect enzymatic activity if Ca is present. Interestingly, Ln ions bind to the Ca site and produce about 4% of the native Ca " " activity . Studies of water proton resonance relaxation (PRR) in the presence of the Gd -substituted enzyme and proenzyme yield respective values of 0.50 and 0.18 mM at pH 5.8 . PRR was used to investigate the binding of the enzyme-Gd complex to monomeric and micellar forms of an homologous series of n-alkylphosphorylcholines. The bound Gd ion was observed to be freely... 

Tyrosine phosphorylation of plasmalemmal receptors or other proteins provides high-affinity binding sites for src homology 2 (SH2)-containing proteins and represents a key targeting mechanism for enzyme translocation. Several groups of tyrosine kinase inhibitors are currently available and have been shown to interfere with enzyme translocation. 

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