to develop a new more accurate spectrophotometric method for detecting monoamine oxidase inhibitors from plant extracts, a series of amine substrates were selected and their ability to be oxidized by monoamine oxidase was evaluated by the hplc method and a new substrate was used to develop a peroxidase-linked spectrophotometric assay. 4-(trifluoromethyl) benzylamine (11) was proved to be an exc...

DuBois, K. P., Albaum, H. G. & Potter, V. R. (1943). J. biol. Chem. 147, 699. Green, H. N. (1943). Lancet, 2, 147. Green, H. N. & Stoner, H. B. (1944). Brit. J. exp. Path. 25, 150. Kal¢kar, H. M. (1943). J. biol. Chem. 148, 127. Kolthoff, I. M. (1932). Saure-Ba8en Indicatoren. Berlin: Springer. Krebs, H. A. & Henseleit, K. (1932). Ho.ppe-Seyl. Z. 210, 33.' Lyubimova, M. N. & Pevsner, D. (1941)....

Spergualin (SG) and 15-deoxyspergualin (DSG) are derivatives of spermidine. Their substrate and inhibitor activities toward amine oxidase from bovine plasma were determined. SG was a good substrate of amine oxidase next to spermidine. The Km and Vmax for SG were 46.5 microM and 0.429 microM/minute, respectively, whereas the Km and Vmax for spermidine were 111 microM and 3.75 microM/minute, resp...

Thirteen recombinant alpha A-crystallin mutants were constructed that differed in the type of amino acid residue directly preceding the sole amine donor lysine for transglutaminases in this protein. The capacity of these mutants to be cross-linked to amine acceptor substrates by tissue transglutaminase and factor XIII was assessed. Two different biotinylated glutamine-containing oligopeptides w...

We report the expression and characterization of a truncated form of MycA from the Mycosubtilin gene cluster from Bacillus subtilis. The MycA fragment contains a new amino transferase (AMT) tailoring domain, allowing the first detailed study of a PLP-dependent enzyme operating in cis within the PKS and NRPS biosynthetic paradigm. As the AMT domain acts on covalently bound beta-ketothioesters, a...

Pepper (Capsicum annuum) serotonin N-hydroxycinnamoyltransferase (SHT) catalyzes the synthesis of N-hydroxycinnamic acid amides of serotonin, including feruloylserotonin and p-coumaroylserotonin. To elucidate the domain or the key amino acid that determines the amine substrate specificity, we isolated a tyramine N-hydroxycinnamoyltransferase (THT) gene from pepper. Purified recombinant THT prot...

Semicarbazide-sensitive amine oxidase (SSAO) is a copper-containing enzyme that catalyzes the oxidative deamination of endogenous and exogenous primary amines. SSAO exists in mammals both as a plasma-soluble and as a membrane-bound form, and its active site is able to come into contact with numerous xenobiotic, amine-containing compounds. The kinetic studies performed in this work showed that c...