Methylated Histidines Alter Tautomeric Preferences that Influence the Rates of Cu Nitrite Reductase Catalysis in Designed Peptides.

ABSTRACT: Copper proteins have the capacity to serve as both redox active catalysts and purely electron transfer centers. A longstanding question in this field is how the function of histidine ligated Cu centers are modulated by δ vs ε-nitrogen ligation of the imidazole. Evaluating the impact of these coordination modes on structure and function by comparative analysis of deposited crystal structures is confounded by factors such as differing protein folds and disparate secondary coordination spheres that make direct comparison of these isomers difficult. Here, we present a series of de novo designed proteins using the noncanonical amino acids 1-methyl-histidine and 3-methyl-histidine to create Cu nitrite reductases where δ- or ε-nitrogen ligation is enforced by the opposite nitrogen's methylation a

SUBMITTER: Koebke KJ 

PROVIDER: S-EPMC6824201 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature