The invention relates to the fields of drug development and biocatalysis, more specifically to a biocatalytic route for asymmetric synthesis of precursors of y-aminobutyric acid (GABA) analogs. Provided is an isolated mutant 4-oxalocrototonate tautomerase (4-OT) enzyme comprising the following mutations (i) leucine at position 8 substituted with a tyrosine (L8Y) or a phenylalanine (L8F); (ii) methionine at position 45 substituted with a tyrosine (M45Y); and (iii) phenylalanine at position 50 substituted with an alanine (F50A), wherein the positions are numbered according to the amino acid sequence of 4-OT of Pseudomonas putida. Also provided is a method for the synthesis of a precursor for the pharmaceutically relevant enantiomer of a GABA analog, comprising (i) providing a y-nitroaldehyde using the 4-OT mutant enzyme, followed by (ii) subjecting the thus obtained y-nitroaldehyde to an enzymatic oxidation reaction catalyzed by an aldehyde dehydrogenase (EC 1.2.1.3).
本发明涉及药物开发和
生物催化领域,更具体地说,涉及一种不对称合成y-
氨基
丁酸(
GABA)类似物前体的
生物催化途径。本发明提供了一种分离的突变体 4-
氧代
丙酮酸同工酶(4-OT),该酶包含以下突变:(i) 第 8 位的亮
氨酸被
酪氨酸(L8Y)或
苯丙
氨酸(L8F)取代;(ii) 第 45 位的蛋
氨酸被
酪氨酸(
M45Y)取代;(iii) 第 50 位的
苯丙
氨酸被丙
氨酸(F50A)取代,其中各位置根据假单胞菌 4-OT 的
氨基酸序列编号。还提供了一种合成
GABA 类似物的药用对映体的前体的方法,包括(i)使用 4-OT 突变体酶提供 y-硝基醛,然后(ii)将由此获得的 y-硝基醛置于
醛脱氢酶(
EC 1.2.1.3)催化的酶促
氧化反应中。