These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Characterization and spectral properties of Proteus mirabilis PR catalase.
    Author: Jouve HM, Gaillard J, Pelmont J.
    Journal: Can J Biochem Cell Biol; 1984 Oct; 62(10):935-44. PubMed ID: 6095975.
    Abstract:
    Purified catalase from a peroxide-resistant mutant (PR) of Proteus mirabilis displayed great similarities with the bovine liver catalase on the basis of its amino acid composition, content in prosthetic groups, and spectroscopic data. The bacterial enzyme was found to have 2.6 +/- 0.2 mol of protoheme IX per tetramer, with an equivalent amount of titrable iron atoms. The optical absorption of P. mirabilis PR catalase in the presence of various anionic species (cyanide, azide, formate) was examined. The dissociation constant of the formate-enzyme complex was determined as 60 +/- 2 mM at pH 7.5. Inhibition and spectral shifts induced by some thiol compounds were very similar to those reported with mammalian catalase. The electron paramagnetic resonance (EPR) spectra (at 9 GHz and 6 K) of bacterial catalase and its various complexes were reported. Two major different rhombic high-spin ferric signals could be seen in the g = 6 region, using either the pure enzyme or the cell crude extract. The balance between the two rhombic forms was reversibly altered by pH. Various changes in rhombicity were also observed after binding with anionic ligands. The EPR spectrum (at 40 K) of nitrosyl ferrous catalase was very similar to reported data with horse liver catalase.
    [Abstract] [Full Text] [Related] [New Search]