Pathogenic Microbiology Commons^™

Comparison Of The Humoral Immune Response Following Both Bacterial Challenge And Rnai Of Major Factors On Proliferation Of Bartonella Quintana In The Human Louse, Jake Zina

Masters Theses

Human body lice, Pediculus humanus humanus, and head lice, Pediculus humanus capitis, have been hematophagous ectoparasites of humans for thousands of years. Despite being ecotypes, only body lice are known to transmit bacterial diseases to humans, and it appears that lower humoral and cellular immune responses allow body lice to possess a higher vector competence. We previously observed that the transcription level of the defensin 1 gene was up-regulated only in head lice following oral challenge of Bartonella quintana, a causative agent of trench fever, and also that body lice excreted more viable B. quintana in their …

Screening For Binding Partners And Protein-Protein Interactions Of A Fungal Transcription Factor- Xdr1, Nishadi Punsara Gallala Gamage

Masters Theses

Clarireedia spp. (formerly Sclerotinia homoeocarpaF.T. Bennett) is the causal agent dollar spot, the most economically important turfgrass disease impacting golf courses in North America. The most effective strategy for dollar spot control is repeated application of multiple classes of fungicides. However, reliance on chemical application has led to resistance to four classes of fungicides as well as multidrug resistance (MDR). Fungi are known to detoxify xenobiotics, like fungicides, through transcriptional regulation of three detoxification phases: modification, conjugation and secretion. Little is known, however, of the protein-protein interactions that facilitate these pathways. Following next-generation RNA sequencing of Clarireedia spp., a …

Studies On The Interaction And Organization Of Bacterial Proteins On Membranes, Mariana Brena

Masters Theses

Bacteria have developed various means of secreting proteins that can enter the host cell membrane. In this work I focus on two systems: cholesterol-dependent cytolysins and Type III Secretion.

Cholesterol is a molecule that is critical for physiological processes and cell membrane function. Not only can improper regulation lead to disease, but also the role cholesterol plays in cell function indicates it is an important molecule to understand. In response to this need, probes have been developed that detect cholesterol molecules in membranes. However, it has been recently shown that there is a need for probes that only respond to …

Trypanosoma Brucei Mitochondrial Dna Polib Cell Cycle Localization And Effect On Polic When Polib Is Depleted, Sylvia L. Rivera

Masters Theses

Trypanosoma brucei is the causative agent of Human African Trypanosomiasis (HAT), also known as African sleeping sickness. T. brucei is unique in several ways that distinguish this organism from other eukaryotes. One of the unique features of T. brucei is the organism’s mitochondrial DNA, which is organized in a complex structure called kinetoplast DNA (kDNA). Since kDNA is unique to the kinetoplastids, kDNA may serve as a good drug target against T. brucei. Previews studies have shown that kDNA has 4 different family A mitochondrial DNA polymerases. Three of these mitochondrial DNA polymerases (POLIB, POLIC, and POLID) are essential …

Distribution Of Enterotoxigenic Clostridium Perfringens Spores In U.S. Retail Spices, Chi-An Lee

Masters Theses

246 samples of bulk and packaged spices from retail stores in the western, southeastern, southern, midwestern, and northeastern areas of the U.S. were examined for the presence of Clostridium -perfringens. Isolates were checked for the presence of the lecithinase gene (cpa) and enterotoxin genes (cpe) by PCR. Enterotoxin formation during sporulation was investigated using the Oxoid Toxin Detection Kit. Forty-three confirmed isolates (from 17% of total samples) were cpa-positive. Of those, 27 were cpe-positive. Together, levels of C. perfringens spores ranged from 3.6-2400/gm. The amount of enterotoxin in cell extracts ranged from …

Characterization Of The Reconstituted And Native Pseudomonas Aeruginosa Type Iii Secretion System Translocon, Kathryn R. Monopoli

Masters Theses

The Type III Secretion (T3S) system is a system utilized by many pathogenic bacteria to inject proteins into host cells during an infection. Effector proteins enter the host cell by passing through the proteinaceous T3S translocon, which forms a pore on the host cell membrane. Pseudomonas aeruginosa is an opportunistic pathogen that utilizes the T3S system, and very little is known about how the P. aeruginosa translocon forms.

The proteins PopB and PopD are believed to assemble into the P. aeruginosa translocon. A pore-forming heterocomplex of PopB and PopD has been reconstituted in model membranes, however this heterocomplex has not …

Eneterotoxigenic Bacillus Cereus And Bacillus Thuringiensis Spores In U.S. Retail Spices, Upasana Hariram

Masters Theses

Bacillus cereus is a ubiquitous organism and a potential foodborne pathogen that can cause two types of gastrointestinal diseases: emesis and diarrhea. The emetic syndrome is caused by a heat and acid stable peptide toxin that is pre-formed in food, while the diarrheal syndrome is associated to two 3-protein, heat labile enterotoxin complexes that are formed in the intestine after ingestion of the organism. There are many reports on the isolation and characterization of Bacillus cereus from various foods, however there are no studies on the levels, toxigenicity and physical characteristics of B. cereus isolated from U.S. retail spices. …