Anthranilate synthase catalyses the conversion of chorismate to anthranilate, a key step in tryptophan biosynthesis. A series of 3-(1-carboxy-ethoxy) benzoic acids were synthesised as chorismate analogues, with varying functionality at C-4, the position of the departing hydroxyl group in chorismate. Most of the compounds were moderate inhibitors of anthranilate synthase, with inhibition constants between 20–30 µM. The exception was 3-(1-carboxy-ethoxy) benzoic acid, (C-4 = H), for which KI
= 2.4 µM. These results suggest that a hydrogen bonding interaction with the active site general acid (Glu309) is less important than previously assumed for inhibition of the enzyme by these aromatic chorismate analogues.
氨茴酸合成酶催化络
氨酸到
氨茴酸的转化,这是色
氨酸
生物合成的一个关键步骤。我们合成了一系列 3-(1-羧基-乙氧基)
苯甲酸作为蝶
氨酸类似物,它们在蝶
氨酸的离去羟基位置 C-4 上具有不同的官能度。大多数化合物都是
蒽酸合成酶的中度
抑制剂,抑制常数在 20-30 µM 之间。例外的是 3-(1-羧基-乙氧基)
苯甲酸(C-4 = H),其 KI = 2.4 µM。这些结果表明,在这些芳香族
氯甲酸类似物对酶的抑制作用中,与活性位点一般酸(Glu309)之间的氢键相互作用没有以前假定的那么重要。