35455-20-0Relevant articles and documents
A new and simple method of resolution. Preparation of 3-fluoro-D-alanine-2-d.
Gal,Chemerda,Reinhold,Purick
, p. 142 - 143 (1977)
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Characterization of d-amino acid aminotransferase from Lactobacillus salivarius
Kobayashi, Jyumpei,Shimizu, Yasuhiro,Mutaguchi, Yuta,Doi, Katsumi,Ohshima, Toshihisa
, p. 15 - 22 (2013/10/22)
We searched a UniProt database of lactic acid bacteria in an effort to identify d-amino acid metabolizing enzymes other than alanine racemase. We found a d-amino acid aminotransferase (d-AAT) homologous gene (UniProt ID: Q1WRM6) in the genome of Lactobacillus salivarius. The gene was then expressed in Escherichia coli, and its product exhibited transaminase activity between d-alanine and α-ketoglutarate. This is the first characterization of a d-AAT from a lactic acid bacterium. L. salivarius d-AAT is a homodimer that uses pyridoxal-5′-phosphate (PLP) as a cofactor; it contains 0.91 molecules of PLP per subunit. Maximum activity was seen at a temperature of 60 °C and a pH of 6.0. However, the enzyme lost no activity when incubated for 30 min at 30 °C and pH 5.5 to 9.5, and retained half its activity when incubated at pH 4.5 or 11.0 under the same conditions. Double reciprocal plots of the initial velocity and d-alanine concentrations in the presence of several fixed concentrations of α-ketoglutarate gave a series of parallel lines, which is consistent with a Ping-Pong mechanism. The Km values for d-alanine and α-ketoglutarate were 1.05 and 3.78 mM, respectively. With this enzyme, d-allo-isoleucine exhibited greater relative activity than d-alanine as the amino donor, while α-ketobutylate, glyoxylate and indole-3-pyruvate were all more preferable amino acceptors than α-ketoglutarate. The substrate specificity of L. salivarius d-AAT thus differs greatly from those of the other d-AATs so far reported.
Thermodynamics and kinetic aspects involved in the enzymatic resolution of (R,S)-3-fluoroalanine in a coupled system of redox reactions catalyzed by dehydrogenases
Goncalves, Luciana P. B.,Antunes,Oestreicher, Enrique G.
, p. 673 - 677 (2012/12/22)
Two systems of redox enzymatic reactions were tested, looking forward to the preparation of (S)-3-fluoroalanine, a potent antibiotic, by kinetic resolution of rac-3-fluoroalanine. This starting material was the main substrate for the deaminative oxidation reaction catalyzed by L-alanine dehydrogenase (L-AlaDH) in the presence of NAD+. One system was formed by coupling this reaction (main reaction) to the reduction of 3-fluoropyruvate (a cascade system) produced in the main reaction catalyzed by L-lactate dehydrogenase (L-LDH) in the presence of NADH, also formed in the main reaction. This system, that was able to achieve 92% of conversion, allows the accumulation of NH 4+, one of the secondary products of the main reaction. The other coupled redox system involved the coupling to the L-AlaDH reaction to the aminative reduction reaction of α-ketoglutarate in the presence of NADH and NH4+ (both side products of the main reaction) catalyzed by L-glutamate dehydrogenase (L-GluDH), that allows accumulation of 3-fluoropyruvate. With this system, the extent of the reaction in the coupled system was only 22%. This big difference in the efficiency of both systems was identified as being the result of a different potency of the products that accumulates in both systems, acting as inhibitors of L-AlaDH. It was demonstrated that 3-fluoropyruvate is a much stronger inhibitor of L-AlaDH than NH4+. This fact, and not thermodynamic considerations, explains the results obtained with both systems.
Simultaneous enzymatic synthesis of (S)-3-fluoroalanine and (R)-3-fluorolactic acid
Goncalves,Antunes,Pinto,Oestreicher
, p. 1465 - 1468 (2007/10/03)
A coupled enzymatic system for the simultaneous synthesis of (S)-3-fluoroalanine (1a) and (R)-3-fluorolactic acid (3) with L-alanine dehydrogenase (L-AlaDH) from Bacillus subtilis and rabbit muscle L-lactate dehydrogenase (L-LDH) using rac-1 and NAD+ is described. Analysis of isolated products of the laboratory preparative scale process revealed 1a in 60% yield and 88% ee and 3 in 80% yield and over 99% ee. The compounds 1a and 3 represent chiral building blocks for the synthesis of several products with pharmacological activity. Copyright (C) 2000 Elsevier Science Ltd.
