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Full-Text Articles in Molecular Biology
Sex Differences In Differential Fear Conditioning During The Acquisition And Consolidation Of Learned Safety, David Sylvan Reis
Sex Differences In Differential Fear Conditioning During The Acquisition And Consolidation Of Learned Safety, David Sylvan Reis
Theses and Dissertations
The ability to distinguish between threatening and non-threatening situations requires careful regulation of behavioral and physiological responses to stress and fear. Deficits in fear regulation are maladaptive and can lead to the development of anxiety disorders such as PTSD. Women are nearly twice as likely to develop PTSD as are men and laboratory animal studies have shown facilitated fear acquisition, resistance to fear extinction, deficits in extinction retention and impaired discrimination between danger and safety cues in females. Taken together this suggests a propensity for reduced inhibitory control over fear responding in females. Here we investigate the mechanisms underlying fear …
An Inducible Fluorescent Reporter System To Measure Lux Operon Promoter Activity, Nicole Thunes
An Inducible Fluorescent Reporter System To Measure Lux Operon Promoter Activity, Nicole Thunes
Theses and Dissertations
Bioluminescence is the enzymatic production of light by a living organism. Many species of marine bacteria produce light with varying degrees of brightness. The lux operon is responsible for bioluminescence and is well studied, however it is currently unknown why different species of bacteria display different brightness levels. A dual-plasmid system designed to mimic the quorum-sensing induction of the lux operon was created and successfully implemented in E. coli. This was accomplished through the use of an arabinose-inducible plasmid containing a luxR gene from Vibrio harveyi, and then using the resulting LuxR protein to activate the lux promoter in a …
New Insights Into The Role Of Antimicrobials Of Xenorhabdus In Interspecies Competition, Kristin Jean Ciezki
New Insights Into The Role Of Antimicrobials Of Xenorhabdus In Interspecies Competition, Kristin Jean Ciezki
Theses and Dissertations
Xenorhabdus spp. are symbionts of entomopathogenic nematodes and pathogens of susceptible insects. The nematodes penetrate the insect midgut to enter the hemocoel where Xenorhabdus bacteria are released, transitioning to their pathogenic stage. During nematode invasion microbes from the insect gut translocate into the hemocoel. In addition, different species of nematodes carrying specific strains of Xenorhabdus can invade a single insect. Xenorhabdus spp thereby engage in competition with both related strains and nonrelated gut microbes. In complex media Xenorhabdus spp produce diverse antimicrobial compounds whose functions in biological systems remain poorly understood. R-type bacteriocins are contractile phage-tail-like structures that are bactericidal …
The Role Of Pilj And Its Structural Domains In The Localization And Function Of The Chp Chemosensory System In Pseudomonas Aeruginosa, Vibhuti Hemantkumar Jansari
The Role Of Pilj And Its Structural Domains In The Localization And Function Of The Chp Chemosensory System In Pseudomonas Aeruginosa, Vibhuti Hemantkumar Jansari
Theses and Dissertations
Bacteria detect environmental signals using membrane-bound methyl-accepting chemotaxis proteins (MCPs), which are part of a larger complex of chemosensory proteins. Pseudomonas aeruginosa has four functionally distinct chemosensory protein complexes. The Chp chemosensory system regulates type IV pili mediated twitching motility and intracellular levels of cAMP by modulating the activity of an adenylate cyclase, CyaB. The Chp system is also proposed to be involved in type IV pili mediated directional twitching motility towards phosphatidylethanolamine (PE). PilJ is the only MCP predicted to be associated with the Chp system. In this study we investigated different domains of PilJ in order to decipher …
Microbial Communities And The Diverse Ecology Of Fecal Indicators At Lake Michigan Beaches, Danielle Cloutier
Microbial Communities And The Diverse Ecology Of Fecal Indicators At Lake Michigan Beaches, Danielle Cloutier
Theses and Dissertations
Fecal indicator bacteria (FIB) such as Escherichia coli (E. coli) and enterococci are used to assess microbiological water quality in recreational waters. The use of FIB follows the assumption that their presence correlates with that of fecal-associated pathogens in recreational waters. The beach ecosystem is complex however and multiple factors can influence the concentration of E. coli and enterococci in the beach environment. Microbial communities within beach sand play a key role in nutrient cycling and are important to the nearshore ecosystem function. E. coli and enterococci, two common indicators of fecal pollution, have been shown to persist in the …
Towards Autonomous Microcystin Detection: Investigating Methods For Automation, Maureen Anne Schneider
Towards Autonomous Microcystin Detection: Investigating Methods For Automation, Maureen Anne Schneider
Theses and Dissertations
Due to increased anthropogenic activity, severe eutrophication is occurring in bodies of water around the world. Effects include decreased water quality, decreased value of surrounding land and recreational use (estimated loss in revenue of 0.67 and 3.96 U.S. billion dollars per year), and increased occurrence of toxin producing Harmful Algal Blooms (HABs). Microcystins are cyclic peptides made up of 7 amino acids and 800-1100 Daltons in size. They are one of the most predominantly produced of these toxins, and therefore was the focus of this study. Numerous structural variants of microcystin (referred to as congeners) exist, but microcystin-LR is one …
A Novel Link Between The Chemotaxis And Biofilm Dispersion Systems Of Pseudomonas Aeruginosa, Jesse Michael Reinhardt
A Novel Link Between The Chemotaxis And Biofilm Dispersion Systems Of Pseudomonas Aeruginosa, Jesse Michael Reinhardt
Theses and Dissertations
Bacterial chemotaxis is the movement of a cell towards an attractant or away from a repellent. This controlled movement is possible due to the chemotaxis system, which is typically made up of several proteins that collectively sense the stimuli and transduce the signal within the cell to mediate a motility response. The chemotaxis proteins of Pseudomonas aeruginosa are encoded in two clusters, which are located at different regions of the chromosome: che I and che V. These gene clusters are known to control chemotaxis via swimming, or flagellar-based, motility. When expressed, these chemotaxis proteins associate with each other to form …