A Panel of TrpB Biocatalysts Derived from Tryptophan Synthase through the Transfer of Mutations that Mimic Allosteric Activation
作者:Javier Murciano-Calles、David K. Romney、Sabine Brinkmann-Chen、Andrew R. Buller、Frances H. Arnold
DOI:10.1002/anie.201606242
日期:2016.9.12
Naturally occurring enzyme homologues often display highly divergent activity with non‐natural substrates. Exploiting this diversity with enzymes engineered for new or altered function, however, is laborious because the engineering must be replicated for each homologue. A small set of mutations of the tryptophan synthase β‐subunit (TrpB) from Pyrococcus furiosus, which mimics the activation afforded
天然存在的酶同系物通常表现出与非天然底物高度不同的活性。然而,用经过改造的酶来开发新功能或改变其功能的多样性是很费力的,因为必须为每个同源物重复进行改造。激烈热球菌色氨酸合酶β亚基(TrpB)的一小部分突变模仿α-亚基结合提供的激活,被证明在不同的TrpB同源物中具有相似的激活作用,序列同一性低至57%。动力学和光谱分析表明,突变通过相同的机制起作用:模仿α-亚基结合。从这些酶中,我们确定了一种新的TrpB催化剂,该催化剂在5取代色氨酸的合成中显示出非常广泛的活性。这证明了变构活化可以在整个蛋白质家族中概括,以探索天然序列多样性以进行所需的生物催化转化。