Threonine Deaminase from Salmonella typhimurium
نویسنده
چکیده
Purified threonine deaminase of Salmonella typhimurium was found to be monodisperse and to have a molecular weight of 194,000. The protein, in 6 M guanidine HCI and 0.1 M P-mercaptoethanol, dissociates into polypeptide chains of molecular weight 48,500. Tryptic peptide analysis implies that the four component chains of the native enzyme are of identical amino acid sequence. L-Isoleucine and L-valine, which are allosteric effecters of this enzyme, have no effect on the sedimentation properties and do not produce detectable changes in the optical rotatory dispersion curve of the native enzyme.
منابع مشابه
Biodegradative L-threonine deaminase of Salmonella typhimurium.
The threonine deaminase formed under anaerobic conditions by Salmonella typhimurium is induced by l-serine and l-threonine, is catabolite repressible, requires cyclic adenosine 3',5'-monophosphate for its synthesis and adenylic acid for optimal activity, and is immunologically different from biosynthetic threonine deaminase.
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