Proton hyperfine resonance assignments in trimethylphosphine ligated ferrimyoglobin using saturation transfer spectroscopy.
1H-NMR saturation transfer spectroscopy and nuclear Overhauser effect (NOE) have been utilized to assign several heme resonances in the low-spin trimethyl phosphine complex of sperm whale metmyoglobin. The two methods permit the location of the heme methyl resonances and the heme 2-vinyl group resonances. A qualitative comparison involving the methyl shift pattern in metMbN3, metMbCN, imidazole metMb and trimethyl phosphine metMb shows a reverse methyl shift between pyrrole I and pyrrole IV. The different hyperfine shift pattern for metMbPMe3 is suggested to arise from: (i) a possible reorientation of the proximal histidine plane; (ii) different heme protein contacts in the different ligated proteins, and (iii) a small contribution from high-spin character. The 2-vinyl group is formed in the cis plane orientation.
Simonneaux
G
G
Laboratoire de Chimie des Organométalliques, URA CNRS 415, Université de Rennes I, France.
Bondon
A
A
Sodano
P
P
D000818:Animals; D006418:Heme; D006420:Hemeproteins / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008786:Metmyoglobin / Q000378:metabolism; D010720:Phosphines; D011487:Protein Conformation; D011522:Protons; D013696:Temperature; D014907:Whales
D006420:Hemeproteins; D010720:Phosphines; D011522:Protons; D008786:Metmyoglobin; D006418:Heme; C049750:trimethyl phosphine