Conversion of canavanine to α-keto-γ-guanidinooxybutyrate and to vinylglyoxylate and 2-hydroxyguanidine

  title={Conversion of canavanine to $\alpha$-keto-$\gamma$-guanidinooxybutyrate and to vinylglyoxylate and 2-hydroxyguanidine},
  author={Marsha M. Hollander and A J Reiter and William H. Horner and Arthur James Cooper},
  journal={Archives of Biochemistry and Biophysics},
Abstract It was observed previously that hydroxyguanidine is formed in the reaction of canavanine(2-amino-4-guanidinooxybutanoate) with amino acid oxidases. The present work shows that hydroxyguanidine is formed by a nonenzymatic β,-γ-elimination reaction following enzymatic oxidation at the α-C and that the abstraction of the β-H is general-base catalyzed. The elimination reaction requires the presence in the α-position of an anion-stabilizing group—the protonated imino group (iminium ion… 
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Mechanisms of cysteine S-conjugate beta-lyases.
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  • Chemistry, Medicine
    Advances in enzymology and related areas of molecular biology
  • 1998
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A preparation obtained from rat liver that catalyzed transamination reactions between glutamine and a variety of a-keto acids was first described by Meister and colleagues.',2 Subsequently, another
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L-Methionine sulfoximine is a substrate of L-amino acid oxidase (Crotalus adamanteus), glutamine transaminase, and gamma-cystathionase. In the reaction catalyzed by L-amino acid oxidase, methionine
Biosynthesis of 7,8-Diaminopelargonic Acid, a Biotin Intermediate, from 7-Keto-8-Aminopelargonic Acid and S-Adenosyl-l-Methionine
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The enzymatic oxidation of homocysteine was investigated with the aim of obtaining alpha-keto-gamma-mercaptobutyrate, a substrate of lactate dehydrogenase, and a scheme is presented which integrates some of the complexities involved in the oxidation metabolism ofhomocyst(e)ine.
Reactivity of the imino acids formed in the amino acid oxidase reaction.
The reactivity of the imino acids formed in the D- or L-amino acid oxidase reaction was studied. It was found that: (1) When imino acids reacted with the alpha-amino group of glycine or other amino
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A weak hydrolytic activity toward arginine appears to be associated with the enzyme, as well as the ability to utilize l -homoarginine as amidine donor at a relatively low rate.
The Biological Effects and Mode of Action of L-Canavanine, a Structural Analogue of L-Arginine
  • G. Rosenthal
  • Biology, Medicine
    The Quarterly Review of Biology
  • 1977
Canavanine is a highly toxic secondary plant constituent that probably functions as an allelochemic agent that deters the feeding activity of phytophagous insects and other herbivores.
Purification and properties of 7, 8-diaminopelargonic acid aminotransferase.
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Spectrophotometric measurement of α-keto acid semicarbazones
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The latter phase of this work revealed conditions for splitting methionine from the molecule and for hydrolysis to adenine and a hitherto unknown fragment, S-ribosylmethionine, which is a prerequisite to microbiological, nutritional, and enzymatic research involving this substance.