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Full-Text Articles in Life Sciences
Invasion Properties Of Listeria Monocytogenes In Aged Cells, Mina Lane Chasteen Burton
Invasion Properties Of Listeria Monocytogenes In Aged Cells, Mina Lane Chasteen Burton
Honors Theses
Listeriosis is a bacterial infection caused by the gram-positive pathogen Listeria monocytogenes. When compared to other foodborne illnesses, listeriosis has a higher death rate due to an increased incidence of complications such as meningitis, hydrocephalus, and sepsis in immunocompromised populations. Elderly individuals experience a condition known as immunosenescence, which is a gradual compromisation of the immune system brought on by natural aging. Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder causing premature aging, which allows HGPS cell lines to be used as models to further research in the field of biogerontology. This study utilizes the F2365 strain of …
Phosphodiesterase D Is Involved In Bile Resistance In Listeria Monocytogenes, Sophia A. Ali
Phosphodiesterase D Is Involved In Bile Resistance In Listeria Monocytogenes, Sophia A. Ali
Honors Theses
Listeria monocytogenes is a deadly foodborne bacterium that is responsible for almost 20% of food-related deaths in the United States. Listeria monocytogenes contaminates ready-to-eat products such as cheese, deli meat, and ice cream. Once ingested, it invades the intestinal lining and can enter the bloodstream, causing listeriosis. There is a gap in the knowledge of the pathogenesis of L. monocytogenes in how it is able to survive in the gastrointestinal tract in the presence of bile, which has bactericidal properties. Previous studies have suggested that the second messenger cyclic-dimeric-GMP may be involved in the regulation of virulence factors of Listeria. …
The Impact Of Oxygen Availability And Oxidative Stress On Regulation Of Cyclic-Dimeric-Gmp In Listeria Monocytogenes Strain F2365, Anna G. Welch
The Impact Of Oxygen Availability And Oxidative Stress On Regulation Of Cyclic-Dimeric-Gmp In Listeria Monocytogenes Strain F2365, Anna G. Welch
Honors Theses
Listeria monocytogenes is a gram-positive foodborne pathogen that results in the infectious disease listeriosis. The second messenger molecule cyclic-dimeric-GMP has been found to be responsible for the regulation of expression of many of its virulence factors with diguanylate cyclases and phosphodiesterases regulating the intracellular concentration of cyclic-di-GMP through synthesis and degradation, respectively. This study investigated the possibility that the availability of oxygen is the environmental signal crucial to the regulation of these enzymes. Prior research in our laboratory has demonstrated that the intracellular concentration of cyclic-di-GMP is elevated when exposed to anaerobic conditions. Due to this, it was hypothesized that …
Assessing The Effect Of Bile And Oxygen Availability On The Redox Status Of Listeria Monocytogenes Strain F2365, Sukriti Bhattarai
Assessing The Effect Of Bile And Oxygen Availability On The Redox Status Of Listeria Monocytogenes Strain F2365, Sukriti Bhattarai
Honors Theses
Although bile is a bactericidal agent able to disrupt membrane structure and cellular homeostasis, including the induction of oxidative stress, Listeria can tolerate bile and also utilize it as a signal to enhance infection and virulence. Preliminary findings showed that under anaerobic conditions, exposure to bile significantly lowered the amount of oxidative damage present in bile-resistant strain F2365 cells. Similarly, Listeria further elicits an adaptive immune response, wherein pre-exposure of the bacterium to stress during food processing or in the host prior to entry into the intestine increases bile tolerance. Based on these previous studies, we hypothesized that bile induces …
The Impact Of Oxygen On The Intracellular Survival Of Listeria Monocytogenes, Amber N. Coats
The Impact Of Oxygen On The Intracellular Survival Of Listeria Monocytogenes, Amber N. Coats
Honors Theses
Listeria monocytogenes is an intracellular pathogen that is responsible for the foodborne disease listeriosis. In order to invade host cells and establish an infection, this pathogen must travel through the gastrointestinal tract where it is exposed to a variety of stressors, including low pH, bile, and variations in oxygen concentrations. These stressors necessitate this organism’s ability to sense and respond to its environment. Previous research has shown that bacteria use two-component systems to sense and regulate genes needed for improved survival in stressful environmental conditions. The goal of this study was to determine if the expression of the putative oxygen …