Department of Biochemistry, University of Washington, Seattle, WA, USA.
Institute for Protein Design, University of Washington, Seattle, WA, USA.
Nature. 2023 Feb;614(7949):774-780. doi: 10.1038/s41586-023-05696-3. Epub 2023 Feb 22.
De novo enzyme design has sought to introduce active sites and substrate-binding pockets that are predicted to catalyse a reaction of interest into geometrically compatible native scaffolds, but has been limited by a lack of suitable protein structures and the complexity of native protein sequence-structure relationships. Here we describe a deep-learning-based 'family-wide hallucination' approach that generates large numbers of idealized protein structures containing diverse pocket shapes and designed sequences that encode them. We use these scaffolds to design artificial luciferases that selectively catalyse the oxidative chemiluminescence of the synthetic luciferin substrates diphenylterazine and 2-deoxycoelenterazine. The designed active sites position an arginine guanidinium group adjacent to an anion that develops during the reaction in a binding pocket with high shape complementarity. For both luciferin substrates, we obtain designed luciferases with high selectivity; the most active of these is a small (13.9 kDa) and thermostable (with a melting temperature higher than 95 °C) enzyme that has a catalytic efficiency on diphenylterazine (k/K = 10 M s) comparable to that of native luciferases, but a much higher substrate specificity. The creation of highly active and specific biocatalysts from scratch with broad applications in biomedicine is a key milestone for computational enzyme design, and our approach should enable generation of a wide range of luciferases and other enzymes.
从头酶设计旨在将预测能催化目标反应的活性位点和底物结合口袋引入到几何上兼容的天然支架中,但由于缺乏合适的蛋白质结构和天然蛋白质序列-结构关系的复杂性而受到限制。在这里,我们描述了一种基于深度学习的“全家族幻觉”方法,该方法生成大量包含不同口袋形状和编码它们的设计序列的理想化蛋白质结构。我们使用这些支架来设计人工荧光素酶,这些酶选择性地催化合成荧光素底物二苯并噻嗪和 2-脱氧色氨酸的氧化化学发光。设计的活性位点将胍基精氨酸定位在反应过程中形成的阴离子附近,该阴离子位于具有高形状互补性的结合口袋中。对于两种荧光素底物,我们都获得了具有高选择性的设计荧光素酶;其中最活跃的是一个小(13.9 kDa)和热稳定的(熔点高于 95°C)酶,其在二苯并噻嗪上的催化效率(k/K = 10 M s)与天然荧光素酶相当,但底物特异性更高。从头开始创建具有广泛生物医学应用的高活性和特异性的生物催化剂是计算酶设计的一个关键里程碑,我们的方法应该能够生成广泛的荧光素酶和其他酶。