H2-uptake activity, spectra, reduction potentials, and kinetics of iron release on the surface of iron core from Azotobacter vinelandii bacterial ferritin

• Published in: Journal of Protein Chemistry 1998-01, Vol.17 (1), p.45-52
• Main Authors: Huang, H Q, Xu, L S, Zhang, F Z, Qui, X H, Lin, Q M, Huang, J W, Zao, H, Huang, N C, Zeng, R Y, Zeng, D
• Format: Article
• Language: English
• Subjects: Azotobacter; Azotobacter vinelandii; Azotobacter vinelandii - chemistry; Azotobacter vinelandii - metabolism; Bacteria; Bacterial Proteins - chemistry; Bacterial Proteins - metabolism; Electrode potentials; Ferritin; Ferritins - chemistry; Ferritins - metabolism; Hydrogen - chemistry; Hydrogen - metabolism; Hydrogen-Ion Concentration; Iron; Kinetics; Molecular biology; Oxidation-Reduction; Proteins; Reduction; Spectrophotometry, Ultraviolet
• ISSN: 0277-8033; 1572-3887; 1573-4943
• DOI: 10.1023/A:1022538530701

Bacterial ferritin from Azotobacter vinelandii (AvBFo) has a function in H2 uptake. The Fe3+ reduction on the surface of the iron core from AvBFo is accompanied simultaneously by H2 uptake, with a maximum activity of H2 uptake of 450 H2/AvBFo. A reduction potential of -402 mV for iron reduction on the surface of the core is found. A shift to the red the protein absorbance peaks ranging from 280 to 290 nm is observed between pH 5 and 9 under 100% H2 reduction. The reduction potential for iron release becomes negative at a rate of 0.025 mV/Fe2+ released. The kinetics of iron release on the surface of the core is a first-order reaction.