Purification and characterization of catalase from goat (Capra capra) lung.
Catalase plays a major role in the protection of tissues from toxic effects of H2O2 and partially reduced oxygen species. In the present study catalase was extracted and purified 330-fold from goat lung by acetone fractionation and successive chromatographies on DEAE-cellulose, Sephadex G-200, Blue Sepharose CL-6B and Ultrogel AcA-34. The purified enzyme was almost homogeneous as judged by polyacrylamide gel electrophoresis and FPLC. The molecular weight and Stokes' radius of the purified enzyme were 339 kDa and 127 +/- 2 A. The enzyme had 11 sulfhydryl groups and 15 tryptophan groups per mol of the enzyme. A broad pH optimum in the range 5.2 to 7.8 was obtained. Sulfhydryl group binding agents, thiol reagents and N-Bromosuccinimide inhibited the enzyme activity. The kinetic data show no cooperativity between the substrate binding sites. Tryptophan, indole acetic acid, cysteine, formaldehyde and sodium azide inhibited the enzyme non-competitively with Ki values of 1.5, 1.6, 6.7, 0.55 and 0.0017 mM, respectively.
Chatterjee
U
U
Department of Biochemistry, Lucknow University, India.
Sanwal
G G
GG
D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D001974:Bromosuccinimide / Q000494:pharmacology; D002374:Catalase / Q000737:chemistry* / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism; D006041:Goats / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008168:Lung / Q000201:enzymology*; D008970:Molecular Weight; D013438:Sulfhydryl Compounds / Q000032:analysis / Q000494:pharmacology; D013439:Sulfhydryl Reagents / Q000494:pharmacology; D014364:Tryptophan / Q000032:analysis
D000596:Amino Acids; D013438:Sulfhydryl Compounds; D013439:Sulfhydryl Reagents; D014364:Tryptophan; D002374:Catalase; D001974:Bromosuccinimide