Cysteine-specific Cu2+ chelating tags used as paramagnetic probes in double electron electron resonance.

ABSTRACT: Double electron electron resonance (DEER) is an attractive technique that is utilized for gaining insight into protein structure and dynamics via nanometer-scale distance measurements. The most commonly used paramagnetic tag in these measurements is a nitroxide spin label, R1. Here, we present the application of two types of high-affinity Cu(2+) chelating tags, based on the EDTA and cyclen metal-binding motifs as alternative X-band DEER probes, using the B1 immunoglobulin-binding domain of protein G (GB1) as a model system. Both types of tags have been incorporated into a variety of protein secondary structure environments and exhibit high spectral sensitivity. In particular, the cyclen-based tag displays distance distributions with comparable distribution widths and most probable distance

SUBMITTER: Cunningham TF 

PROVIDER: S-EPMC4349203 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature