U. Chatterjee et Gg. Sanwal, PURIFICATION AND CHARACTERIZATION OF CATALASE FROM GOAT (CAPRA-CAPRA)LUNG, Molecular and cellular biochemistry, 126(2), 1993, pp. 125-133
Catalase plays a major role in the protection of tissues from toxic ef
fects of H2O2 and partially reduced oxygen species. In the present stu
dy catalase was extracted and purified 330-fold from goat lung by acet
one fractionation and successive chromatographies on DEAE-cellulose, S
ephadex G-200, Blue Sepharose CL-6B and Ultrogel AcA-34. The purified
enzyme was almost homogeneous as judged by polyacrylamide gel electrop
horesis and FPLC. The molecular weight and Stokes' radius of the purif
ied enzyme were 339 kDa and 127 +/- 2 Angstrom. The enzyme had 11 sulf
hydryl 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 bind
ing agents, thiol reagents and N-Bromosuccinimide inhibited the enzyme
activity. The kinetic data show no cooperativity between the substrat
e binding sites. Tryptophan, indole acetic acid, cysteine, formaldehyd
e and sodium azide inhibited the enzyme non-competitively with K-i val
ues of 1.5, 1.6, 6.7, 0.55 and 0.0017 mM, respectively.