ESR Resolves the C Terminus Structure of the Ligand-free Human Glutathione S-Transferase A1-1.

ABSTRACT: Nitroxide- and Cu²⁺-based electron spin resonance (ESR) are combined to provide insight into the conformational states of the functionally important α-helix of the human glutathione S-transferase A1. Distance measurements on various spin-labeled dimeric human glutathione S-transferase A1-1 all result in bimodal distance distributions, indicating that the C-terminus exists in two distinct conformations in solution, one of which closely matches that found in the crystal structure of the ligand-bound enzyme. These measurements permit the generation of a model of the unliganded conformation. Room temperature ESR indicates that the second conformation has high mobility, potentially enabling the enzyme's high degree of substrate promiscuity. This model is then validated using computat

SUBMITTER: Lawless MJ 

PROVIDER: S-EPMC5985033 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature