Isolation and Characterization of Staphylococcus Aureus Mf-31 Catalase (Enzyme, Protein)
Barrier, William Alfred
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/70078
Description
Title
Isolation and Characterization of Staphylococcus Aureus Mf-31 Catalase (Enzyme, Protein)
Author(s)
Barrier, William Alfred
Issue Date
1984
Department of Study
Food Science
Discipline
Food Science
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Agriculture, Food Science and Technology
Abstract
S. aureus MF-31 catalase was purified to homogeneity using ethanol-chloroform fractionation, ammonium sulfate precipitation, ultrafiltration and gel filtration.
The optimal pH for S. aureus MR-31 catalase was between pH 5 - pH 6. The enzyme was stable over the range pH 4 - pH 9. The apparent isoelectric point was 5.3 (+OR-) 0.01 pH units. With respect to temperature stability, S. aureus MR-31 was stable at 52(DEGREES)C after 45 minutes of heating. The enzyme was inactivated at 60(DEGREES)C for ten minutes, however this was dependent on the concentration of the enzyme and the presence of protectants. The apparent subunit molecular was 64,000 (+OR-) 1000 daltons, whereas the apparent native molecular weight was 235,000 (+OR-) 5000 daltons. Amino acid analysis revealed that S. aureus MF-31 catalase was similar to amino acid analyses of catalase from other sources. The iron content of S. aureus MF-31 catalase was found to be 0.089%, comparing favorably with other published findings. The enzyme was inhibited by millimolar concentrations of sodium cyanide, sodium azide and hydroxylamine, results indicating the presence of a heavy metal catalyst.
The effects of salt, pH and salt concentration with heating on catalase activity of S. aureus MF-31 were examined. The results indicated that of the variables tested, pH played a major role. The chloride anion inhibited catalase activity at low pH. But this inhibition was influenced by the cation. Sodium chloride was more inhibitory at low pH than either potassium chloride or magnesium chloride.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
