Naslov
Haem Accessibility in Cytochrome P-450 from Rabbit Liver. A Proton Magnetic Relaxation Study by Stereochemical Probes

Autori
Rein, H. ; Maričić, Siniša ; Jänig, G.-R. ; Vuk-Pavlović, Stanimir ; Benko, Bojan ; Ristau, O. ; Ruckpaul, K.

Izvornik
Biochimica et Biophysica Acta. Protein Structure (0006-3002) 446 (1976), 1; 325-330

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Aniline; Cytochrom P-450; Electron spin resonance; Phenobarbital; Proton magnetic relaxation; Spasman

Sažetak
Cytochrome P-450 was solubilized from phenobarbital induced rabbit liver and purified by affinity chromatography. The longitudinal proton magnetic relaxation rates of this ferric, low-spin sample (as confirmed by ESR) in 20% glycerol aqueous solution are very large compared with low-spin methaemoglobin and myoglobin derivatives. Similarly high rates were measured in a deuterated solution using the aliphatic protons of glycerol as stereochemical markers, which strongly suggests that the haem iron in cytochrome P-450 is much more accessible to the solvent than in harmoglobin or myoglobin. Type I substrate (Spasman) produced small but significant increases in NMR rates both in the H2O and in the 2H2O solution, while binding of aniline (Type II substrate) doubled the rates.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija, Biologija

POVEZANOST RADA