52809-07-1Relevant articles and documents
Syntheses of (S)-β-pyrazolylalanine and (S)-quisqualic acid from a serine-derived aziridine
Farthing, Christopher N.,Baldwin, Jack E.,Russell, Andrew T.,Schofield, Christopher J.,Spivey, Alan C.
, p. 5225 - 5226 (2007/10/03)
The naturally occurring amino acids (S)-β-pyrazolylalanine and (S)- quisqualic acid are synthesised via the nucleophilic ring-openings of an optically active aziridine by pyrazole and 1,2,4-oxadiazolidine-3,5-dione, respectively.
BIOSYNTHESIS OF β-(1,2,4-TRIAZOL-1-YL)ALANINE IN HIGHER PLANTS
Ikegami, Fumio,Komada, Yumiko,Kobori, Masuko,Hawkins, Douglas R.,Murakoshi, Isamu
, p. 2507 - 2508 (2007/10/02)
β-(1,2,4-triazol-1-yl)Alanine, an important metabolite of the triazole-based fungicide Myclobutanil, was shown to be derived from O-acetyl-L-serine and 1,2,4-triazole by cysteine synthase in higher plants.Some properties of this enzyme in the biosynthesis of β-(1,2,4-triazol-1-yl)alanine are described.
PURIFICATION AND PROPERTIES OF β-CYANO-L-ALANINE SYNTHASE FROM SPINACIA OLERACEA
Ikegami, Fumio,Takayama, Kyoko,Tajima, Chiho,Murakoshi, Isamu
, p. 2011 - 2016 (2007/10/02)
β-Cyano-L-alanine synthase was purified ca 6200-fold to homogeneity from the leaves of spinach (Spinacia oleracea).The purified enzyme has an apparent Mr of 60 000 and can be dissociated into identical subunits of Mr 30 000.The subunits each contain one molecule of pyridoxal 5'-phosphate.The Km value is 2.3 mM for L-cysteine and 0.73 mM for cyanide. β-Cyano-L-alanine synthase from S. oleracea also catalyses the formation of some S-substituted L-cysteines and some heterocyclic β-substituted alanines from L-cysteine or O-acetyl-L-serine.The specificity of these additional catalytic activities of the purified enzyme are compared with those of cysteine synthase purified from the same plant, and with those of β-cyano-L-alanine synthase purified from other sources.Some other properties, including the amino acid composition of the purified enzyme, are also described. - Key Word Index: Spinacia oleracea; Chenopodiaceae; spinach; β-cyano-L-alanine synthase; cysteine synthase; enzyme purification; amino acid composition; L-cysteine; O-acetyl-L-serine; β-cyano-L-alanine; heterocyclic β-substituted alanines.
Biomimetic Synyhesis of Heterocyclic β-Substituted Alanines by Pyridoxal 5'-Phosphate-Catalyzed Chemical Reactions
Murakoshi, Isamu,Ikegami, Fumio,Yoneda, Yoshihiro,Ihara, Harumi,Sakata, Kumiko,Koide, Chiharu
, p. 1473 - 1478 (2007/10/02)
Several heterocyclic β-substituted alanines were biomimetically synthesized by incubating 0.1M acetate buffer solution containing the appropriate heterocyclic compound and O-acetylserine or serine in the presence of pyridoxal 5'-phosphate (PLP) and metal ions.This PLP-catalyzed chemical reaction depends upon pH, metal ions and temperature.The addition of Ga3+, Fe3+ or Al3+ enhanced the rate of synthesis.The optimum of the various reaction conditions of this biomimetic method is described.Keywords - biomymetic synthesis; amino acid synthesis; heterocyclic β-substituted alanine; non-protein amino acid; O-acetylserine; N-heterocyclic compound; pyridoxal 5'-phosphate; metal ion
ENZYMATIC SYNTHESIS OF THE NEUROEXCITATORY AMINO ACID QUISQUALIC ACID BY CYSTEINE SYNTHASE
Murakoshi, Isamu,Kaneko, Masakazu,Koide, Chiharu,Ikegami, Fumio
, p. 2759 - 2764 (2007/10/02)
Key Word Index - Quisqualis indica var. villosa; Combretaceae; cysteine synthase; isoenzyme; enzyme purification; biosynthesis; heterocyclic β-substituted alanines; quisqualic acid; O-acetyl-L-serine; cysteine.Purification of cysteine synthase from the leaves of Quisqualis indica var. villosa reveals the presence of two forms of this enzyme, separated by chromatography on DEAE-Sephadex A-50.Isoenzyme A was purified 10 000-fold and had a specific activity of 10.8 U/mg protein.Isoenzyme B was purified 460-fold with a specific activity of 0.49 U/mg protein.Both isoenzymes have the same Mrs (58 000) and dissociate into identical subunits (Mr 29 000).The Km value of isoenzyme A is 1.9 mM for O-acetyl-L-serine and 59 μM for sulphide, while that of isoenzyme B is 7.1 mM for O-acetyl-L-serine and 4.0 mM for 3,5-dioxo-1,2,4-oxadiazolidine.Both isoenzymes catalyse the formation of cysteine from O-acetyl-L-serine and hydrogen sulphide, but only isoenzyme B catalyses the formation of L-quisqualic acid.Other significant differences occur in the substrate specificity of the two isoenzymes.Some properties of the purified cysteine synthase isoenzymes are also described.
Synthesis of L-Quisqualic Acid: A General Method for Enantio-efficient Synthesis of β-Aminoalanine Derivatives
Baldwin, Jack E.,Adlington, Robert M.,Birch, David J.
, p. 256 - 257 (2007/10/02)
A general method for the enantio-efficient synthesis of β-aminoalanine derivatives, which involves intramolecular transfer of the amino substituent from the α-carboxy to the β-carbon atom wia an azetidinone is described with its application to an efficient synthesis of the neuroexcitatory quisqualic acid in an optically pure state.
