NMR and homology modeling studies of copper(II)-halocyanin from Natronobacterium pharaonis bacteria

Abstract Halocyanin from the haloalkaliphilic archaean Natronobacterium pharaonis is a peripheral membrane type 1 blue copper protein with a single polypeptide chain of 163 amino acid residues. Halocyanin participates as putative electron carrier protein associated to an electron acceptor role for a terminal oxidase and has the lowest redox potential value reported to date for a BCP. NMR studies and homology modeling calculations were performed to evaluate the electronic properties of Cu(II)-halocyanin from Natronobacterium pharaonis . The copper coordination site properties of Cu(II)-halocyanin are discussed. The 1 H NMR spectra, isotropic chemical shifts and relaxation times for halocyani…