Dataset Information

The effect of oxygen on bile resistance in L. monocytogenes

ABSTRACT: Listeria monocytogenes is a gram-positive, facultative anaerobe food-borne pathogen that is the causative agent of listeriosis. Upon ingestion, L. monocytogenes is subjected to a variety of non-specific host defenses such as bile. The main component of bile is bile salts which is known to be bactericidal through inducing DNA damage, oxidative damage, membrane instability, and protein misfolding. Previous studies have focused mainly on aerobic conditions; however the human GI tract is an environment ranging from microaerophilic to anaerobic. The bile salt hydrolase, an enzyme known to reduce toxicity of bile through hydrolysis, has been shown to have an increase in activity under anaerobic conditions. Therefore, the purpose of this study was to determine the effect of oxygen on bile resistance and determine the bile specific proteome that is responsible for this. To do this, we performed survival assays on virulent strains: F2365, 10403S, EGDe and avirulent strain, HCC23. Results showed an increase in viability for all virulent strains when exposed to porcine bile under anaerobic conditions. Interestingly, an increase in resistance was seen in HCC23 only under aerobic conditions. We then used a total proteomic analysis approach to compare the bile specific proteome under both aerobic and anaerobic conditions. Results showed many difference between all strains including an increase in abundance of proteins associated with stress responses, repair, cell morphology, and cell division under anaerobic conditions. Response to bile salt stress showed to be strain dependent. This study not only identified proteins responsible for L. monocytogenes bile resistance but also differerences between aerobic and anaerobic conditions thus suggesting that oxygen availability is not only a stressor but in some way providing assistance to overcoming bile salts.

INSTRUMENT(S): LTQ Velos

ORGANISM(S): Listeria Monocytogenes

TISSUE(S): Prokaryotic Cell

DISEASE(S): Listeriosis

SUBMITTER: Joseph Reddy

LAB HEAD: Janet Donaldson

PROVIDER: PXD002243 | Pride | 2017-05-03

REPOSITORIES: Pride

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Publications

The Effect of Oxygen on Bile Resistance in <i>Listeria monocytogenes</i>.

Wright Morgan L ML Pendarvis Ken K Nanduri Bindu B Edelmann Mariola J MJ Jenkins Haley N HN Reddy Joseph S JS Wilson Jessica G JG Ding Xuan X Broadway Paul R PR Ammari Mais G MG Paul Oindrila O Roberts Brandy B Donaldson Janet R JR

Journal of proteomics & bioinformatics 20160405 4

<i>Listeria monocytogenes</i> is a Gram-positive facultative anaerobe that is the causative agent of the disease listeriosis. The infectious ability of this bacterium is dependent upon resistance to stressors encountered within the gastrointestinal tract, including bile. Previous studies have indicated bile salt hydrolase activity increases under anaerobic conditions, suggesting anaerobic conditions influence stress responses. Therefore, the goal of this study was to determine if reduced oxygen ...[more]

PMID: 27274623

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			Action	DRS
	1.mgf	Mgf
	1.raw	Raw
	10.mgf	Mgf
	10.raw	Raw
	10403S.faa	Other

Dataset Information

The effect of oxygen on bile resistance in L. monocytogenes

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Publications

The Effect of Oxygen on Bile Resistance in <i>Listeria monocytogenes</i>.

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