Specificity Effects of Amino Acid Substitutions in Promiscuous Hydrolases: Context-Dependence of Catalytic Residue Contributions to Local Fitness Landscapes in Nearby Sequence Space.
Specificity Effects of Amino Acid Substitutions in Promiscuous Hydrolases: Context-Dependence of Catalytic Residue Contributions to Local Fitness Landscapes in Nearby Sequence Space.
复制标题
DOI：
10.1002/cbic.201600657
复制
发表时间：
2017-06-01
期刊：
影响因子：
--
通讯作者：
Hollfelder F
中科院分区：
文献类型：
--
作者：
Bayer CD;van Loo B;Hollfelder F
催化混杂可以促进酶功能的进化--多功能催化剂可以作为有效功能适应的跳板。我们在两组混杂的AP超家族成员中测试单个突变对多种活动的影响，以探索这一假说。我们量化了两个超家族成员：芳基硫酸酯酶(AS)和磷酸单酯水解酶(PMH)中类似的亲核侧翼残基的位置饱和突变的影响。统计分析表明，没有一个物理化学特征本身就能解释突变效应。相反，这些影响似乎受到其结构性背景的主导。同样，改变催化亲核试剂本身的效果也不是特定于反应类型的。将四种活动的“适应图景”映射到所选序列位置的可能变异上，揭示了通过单点突变使AP超家族成员重新专门化的巨大潜力，突出了催化混杂是适应潜力的强大预测因子。
Catalytic promiscuity can facilitate evolution of enzyme functions—a multifunctional catalyst may act as a springboard for efficient functional adaptation. We test the effect of single mutations on multiple activities in two groups of promiscuous AP superfamily members to probe this hypothesis. We quantify the effect of site‐saturating mutagenesis of an analogous, nucleophile‐flanking residue in two superfamily members: an arylsulfatase (AS) and a phosphonate monoester hydrolase (PMH). Statistical analysis suggests that no one physicochemical characteristic alone explains the mutational effects. Instead, these effects appear to be dominated by their structural context. Likewise, the effect of changing the catalytic nucleophile itself is not reaction‐type‐specific. Mapping of “fitness landscapes” of four activities onto the possible variation of a chosen sequence position revealed tremendous potential for respecialization of AP superfamily members through single‐point mutations, highlighting catalytic promiscuity as a powerful predictor of adaptive potential.