Catalase, superoxide dismutase, and hemolysin in the virulence of Listeria monocytogenes
Dallmier, Anthony Wayne
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/2142/21365
Description
Title
Catalase, superoxide dismutase, and hemolysin in the virulence of Listeria monocytogenes
Author(s)
Dallmier, Anthony Wayne
Issue Date
1991
Doctoral Committee Chair(s)
Blaschek, Hans-Peter M.
Department of Study
Food Science and Human Nutrition
Discipline
Food Science and Human Nutrition
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Agriculture, Food Science and Technology
Biology, Microbiology
Language
eng
Abstract
Six strains of Listeria monocytogenes were examined for catalase, superoxide dismutase (SOD), and listeriolysin O (LLO) activities. The two strains having the lowest catalase activities also possessed the lowest SOD activities. Exogenous hydrogen peroxide was added to suspensions of four L. monocytogenes strains; strains producing the highest catalase levels showed the greatest H$\sb2$O$\sb2$ resistance. Only two strains of L. monocytogenes examined exhibited LLO activity. Various concentrations of NaCl were added to growth media prior to bacterial inoculation. Most strains showed an increase in catalase, SOD, and LLO activities when propagated in media containing 428 mM NaCl (TSBS) followed by a decline in activities at greater NaCl concentrations. Potassium chloride was added to the growth media at identical molar concentrations as NaCl for two L. monocytogenes strains. Stimulation and depression of enzyme activities followed the trends found for cells grown in media containing added NaCl. The catalase and SOD activities were generally higher when cells were grown in media containing NaCl than in media containing equimolar KCl concentrations. The LLO titer for L. monocytogenes 10403S grown in a medium containing 428 mM KCl (TSBK) was approximately 50% higher than when propagated in TSBS. A hemolytic L. monocytogenes strain and a nonhemolytic mutant of this strain grown in media containing either no added salt (TSBW), various concentrations of NaCl, or various concentrations of KCl were injected into ten-day-old chick embryos to relate virulence factor production with pathogenicity. The hemolytic strain gave an LD$\sb{50}$ less than a single cell when grown in many of the aforementioned media while the nonhemolytic strain exhibited a higher LD$\sb{50}$ when propagated in TSBW compared to the other media. The same two strains grown in either TSBW, TSBS, or TSBK were injected into mice. No significant difference (p $<$ 0.05) in virulence was found for cells propagated in any of the growth media. The heat resistance of four strains was examined. No correlation between heat sensitivity and enzyme production could be determined. Cells of one strain grown in media containing the higher NaCl levels tested exhibited enhanced heat lability compared to cells grown in media containing lower NaCl concentrations.
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.
