RUcore: Rutgers University Community Repository
Listeria monocytogenes adjusts its membrane fluidity, ATPase activity and atpE transcription levels in response to cold and acid stress
Descriptive
TypeOfResource
Text
TitleInfo
(ID = T-1)
Title
Listeria monocytogenes adjusts its membrane fluidity, ATPase activity and atpE transcription levels in response to cold and acid stress
Identifier
ETD_1573
Identifier
(type = hdl)
http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051169
Language
LanguageTerm
(authority = ISO639-2);
(type = code)
eng
Genre
(authority = marcgt)
theses
Subject
(ID = SBJ-1);
(authority = RUETD)
Topic
Food Science
Subject
(ID = SBJ-1);
(authority = ETD-LCSH)
Topic
Listeria monocytogenes
Abstract
Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a disease associated with a high mortality rate. The organism responds to a variety of stresses by activating stress-response pathways and adjusting its membrane fluidity by altering its fatty acid composition. We hypothesize that the F0F1 ATPase plays a central role in L. monocytogenes' response to multiple stresses. Wild-type and mutant cells were used to investigate the response to cold, acid, and nisin. The branched-chain fatty acid deficient, cold-sensitive mutant strain, cld1, showed significantly higher membrane rigidity (r = 0.175) compared to its wild-type 10403s (r = 0.121) when grown at 30°C, but not at 15°C (r = 0.124 and 0.116, respectively). Strain cld1 adjusted its membrane fluidity to cold stress. The F0F1 ATPase activity in strain cld1 was 3-fold higher than that of wild-type strain 10403s (0.0267 vs 0.0097 μmole Pi/min.mg protein, respectively) when cells were grown at 30°C. Supplementing cld1's growth medium with the precursor to branched fatty acid, 2-methylbutyrate, restored its fluidity but not the F0F1 ATPase activity to wild-type levels. The acid tolerance response examined differences in initial acid-sensitivity and development of tolerance to lactic acid. Strain cld1 had decreased viability when directly exposed to pH 3.5 (2.64 log CFU/ml), but gained increased viability at pH 3.5 after exposure to pH 5.5 (8.62 log CFU/ml) compared to the wild-type. Finally, a genetic approach examined the F0F1 ATPase c-subunit (atpE) expression in strains 10403s and cld1 using real-time PCR. Strain cld1 showed a 10-fold lower atpE mRNA transcript compared to 10403s. When examining the generated data, we observed that strain cld1 has higher F0F1 ATPase activity, higher initial acid sensitivity, increased protection due to the acid tolerance response, and lower c-subunit mRNA compared to strain 10403s in addition to a rigid membrane. These results support the hypothesis that adjustments took place at the level of the F0F1 ATPase. The various data were pooled in a model in which the mutant strain cld1 has a smaller c-subunit carousel compared to its wild-type 10403s, and highlights the important role of the ATPase in microbial stress response.
PhysicalDescription
Form
(authority = gmd)
electronic resource
Extent
xvii, 163 p. : ill.
InternetMediaType
application/pdf
InternetMediaType
text/xml
Note
(type = degree)
Ph.D.
Note
(type = bibliography)
Includes bibliographical references (p. 116-130)
Note
(type = statement of responsibility)
by Mohamed Z. Badaoui Najjar
Name
(ID = NAME-1);
(type = personal)
NamePart
(type = family)
Badaoui Najjar
NamePart
(type = given)
Mohamed Z.
Role
RoleTerm
(authority = RULIB);
(type = )
author
DisplayForm
Mohamed Z. Badaoui Najjar
Name
(ID = NAME-2);
(type = personal)
NamePart
(type = family)
Montville
NamePart
(type = given)
Thomas
Role
RoleTerm
(authority = RULIB);
(type = )
chair
Affiliation
Advisory Committee
DisplayForm
Thomas J. Montville
Name
(ID = NAME-3);
(type = personal)
NamePart
(type = family)
Chikindas
NamePart
(type = given)
Michael
Role
RoleTerm
(authority = RULIB);
(type = )
internal member
Affiliation
Advisory Committee
DisplayForm
Michael L. Chikindas
Name
(ID = NAME-4);
(type = personal)
NamePart
(type = family)
Ludescher
NamePart
(type = given)
Richard
Role
RoleTerm
(authority = RULIB);
(type = )
internal member
Affiliation
Advisory Committee
DisplayForm
Richard D. Ludescher
Name
(ID = NAME-5);
(type = personal)
NamePart
(type = family)
Annous
NamePart
(type = given)
Bassam
Role
RoleTerm
(authority = RULIB);
(type = )
outside member
Affiliation
Advisory Committee
DisplayForm
Bassam A. Annous
Name
(ID = NAME-1);
(type = corporate)
NamePart
Rutgers University
Role
RoleTerm
(authority = RULIB);
(type = )
degree grantor
Name
(ID = NAME-2);
(type = corporate)
NamePart
Graduate School - New Brunswick
Role
RoleTerm
(authority = RULIB);
(type = )
school
OriginInfo
DateCreated
(point = );
(qualifier = exact)
2009
DateOther
(qualifier = exact);
(type = degree)
2009-05
Place
PlaceTerm
(type = code)
xx
Location
PhysicalLocation
(authority = marcorg)
NjNbRU
RelatedItem
(type = host)
TitleInfo
Title
Rutgers University Electronic Theses and Dissertations
Identifier
(type = RULIB)
ETD
RelatedItem
(type = host)
TitleInfo
Title
Graduate School - New Brunswick Electronic Theses and Dissertations
Identifier
(type = local)
rucore19991600001
Identifier
(type = doi)
doi:10.7282/T3J67H57
Genre
(authority = ExL-Esploro)
ETD doctoral
Back to the top
Rights
RightsDeclaration
(AUTHORITY = GS);
(ID = rulibRdec0006)
The author owns the copyright to this work.
Copyright
Status
Copyright protected
Availability
Status
Open
RightsEvent
(AUTHORITY = rulib);
(ID = 1)
Type
Permission or license
Detail
Non-exclusive ETD license
AssociatedObject
(AUTHORITY = rulib);
(ID = 1)
Type
License
Name
Author Agreement License
Detail
I hereby grant to the Rutgers University Libraries and to my school the non-exclusive right to archive, reproduce and distribute my thesis or dissertation, in whole or in part, and/or my abstract, in whole or in part, in and from an electronic format, subject to the release date subsequently stipulated in this submittal form and approved by my school. I represent and stipulate that the thesis or dissertation and its abstract are my original work, that they do not infringe or violate any rights of others, and that I make these grants as the sole owner of the rights to my thesis or dissertation and its abstract. I represent that I have obtained written permissions, when necessary, from the owner(s) of each third party copyrighted matter to be included in my thesis or dissertation and will supply copies of such upon request by my school. I acknowledge that RU ETD and my school will not distribute my thesis or dissertation or its abstract if, in their reasonable judgment, they believe all such rights have not been secured. I acknowledge that I retain ownership rights to the copyright of my work. I also retain the right to use all or part of this thesis or dissertation in future works, such as articles or books.
Back to the top
Technical
ContentModel
ETD
MimeType
(TYPE = file)
application/pdf
MimeType
(TYPE = container)
application/x-tar
FileSize
(UNIT = bytes)
1464320
Checksum
(METHOD = SHA1)
dcb1c0775b794532284629f0941b5362298ed4fe
Back to the top
Statistical Profile