Bacteriology Commons^™

Characterization Of Silicon Ion Exposure On Deinococcus Radiodurans, Richard F. Daughtry

Theses and Dissertations

Deinococcus radiodurans is a robust bacterium that is known for its extraordinary resistance to ionizing radiation. In general, many of the investigations of this bacterium's resistance have revolved around low linear energy transfer radiation, such as gamma and electron radiation. This study explored Deinococcus radiodurans's ability to survive high linear energy transfer radiation, specifically proton and neutron radiation. Deinococcus radiodurans was dehydrated to reduce the effects of low linear energy transfer radiation. The bacteria were exposed to both neutron and proton radiation of varying amounts and rehydrated. The resulting colonies were counted and compared to colonies of non-irradiated control samples …

Rapid Identification And Typing Of Mycobacterium Avium Complex Using Matrix Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (Maldi-Tof) Library And Biomarker Based Approaches, Claudia Antonika, John Dustin Loy, Raul Barletta, Michael Collins

UCARE: Research Products

Bacteria associated with the Mycobacterium avium complex (MAC) cause significant problems in animal agriculture and cause large economic losses and morbidity of livestock. Two clinically important subspecies of M. avium are M.avium ssp paratuberculosis (MAP) and M. avium ssp hominissuis (MAH). MAP is the etiologic agent of Johne’s disease, a chronic and fatal enteritis in ruminants, that has been linked to Crohn’s disease in humans.1 MAH has zoonotic potential as it is one of the leading causes of secondary infections in AIDS patients. Identification of M. avium in clinical samples is challenging as they have overlapping host ranges and clinical …

Gene Co-Occurrence Networks Reflect Bacteriophage Ecology And Evolution, Jason W. Shapiro, Catherine Putonti

Biology: Faculty Publications and Other Works

Bacteriophages are the most abundant and diverse biological entities on the planet, and new phage genomes are being discovered at a rapid pace. As more phage genomes are published, new methods are needed for placing these genomes in an ecological and evolutionary context. Phages are difficult to study by phylogenetic methods, because they exchange genes regularly, and no single gene is conserved across all phages. Here, we demonstrate how gene-level networks can provide a high-resolution view of phage genetic diversity and offer a novel perspective on virus ecology. We focus our analyses on virus host range and show how network …

Effects Of Elevated Hydrostatic Pressure Against Mesophilic Background Microflora And Habituated Salmonella Serovars In Orange Juice, Abimbola Allison, Edward Daniels, Shahid Chowdhury, Aliyar Fouladkhah

Agricultural and Environmental Sciences Faculty Research

With recent improvements in the commercial feasibility of high pressure pasteurization units, the technology is gaining rapid acceptability across various sectors of food manufacturing, thus requiring extensive validation studies for effective adoption. Various times (1 min to 10 min) and intensity levels (0 MPa to 380 MPa) of elevated hydrostatic pressure were investigated for decontamination of mesophilic background microflora and inoculated Salmonella in orange juice. Results were analyzed by GLM procedure of SAS using Tukey- and Dunnett-adjusted ANOVA, additionally the Kmax and D-values were calculated using best-fitted (maximum R2) model obtained by GInaFit software. At 380 MPa, for treatments of …

Gas Plasma Pre-Treatment Increases Antibiotic Sensitivity And Persister Eradication In Methicillin-Resistant Staphylococcus Aureus, Li Guo, Ruobing Xu, Yiming Zhao, Dingxin Liu, Zhijie Liu, Xiaohua Wang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of serious nosocomial infections, and recurrent MRSA infections primarily result from the survival of persister cells after antibiotic treatment. Gas plasma, a novel source of ROS (reactive oxygen species) and RNS (reactive nitrogen species) generation, not only inactivates pathogenic microbes but also restore the sensitivity of MRSA to antibiotics. This study further found that sublethal treatment of MRSA with both plasma and plasma-activated saline increased the antibiotic sensitivity and promoted the eradication of persister cells by tetracycline, gentamycin, clindamycin, chloramphenicol, ciprofloxacin, rifampicin, and vancomycin. The short-lived ROS and RNS generated by plasma …

Comparison Of Beta-Lactamase Genes In Environmental Rahnella Isolates, Katherine D'Angelo, Ray A. Larsen

Honors Projects

Antibiotic resistance is a growing problem in the field of healthcare. Antibiotics are becoming less effective as species of bacteria adapt and share resistance mechanisms. If transmission of mechanisms can be better understood at the molecular level, inhibitors could be developed to lessen the likelihood of antibiotic resistance. In this study, Rahnella spp were isolated from environmental sources on MacConkey plates containing 100 µg ml^-1 ampicillin, and confirmed by 16S rRNA gene sequencing. Whole genomic DNA was extracted from isolates and initial amplifications were performed by polymerase chain reaction (PCR) using primers specific for 16S amplification. New primers were …

Mrub_2120, Mrub_2121, Mrub_2122, Mrub_2123 And Mrub_2124 Are Orthologs Of E. Coli Genes B3458, B3457, B3456, B3455 And B3454, Respectively, And Make Up An Operon That Codes For The Branched-Chain Amino Acid Abc Transporter In Meiothermus Ruber Dsm 1279, Aaron Jones, Madelyn Huber, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

In this project we investigated the biological function of the genes Mrub_2120, Mrub_2121, Mrub_2122, Mrub_2123 and Mrub_2124 (KEGG map number 02010). We predict these genes encode components of a branched-chain amino acid ATP Binding Cassette (ABC) transporter: 1) Mrub_2120 (DNA coordinates 2169247-2170416 on the reverse strand) encodes the branched-chain amino acid binding protein that is localized to the periplasm; 2) Mrub_2121 (DNA coordinates 2170433..2171353 on the reverse strand) encodes the first TMD; 3) Mrub_2122 (DNA coordinates 2171365..2172279 on the reverse strand) encodes the second TMD; 4) Mrub_2123 (DNA coordinates 2172276..2173028 on the reverse strand) encodes the first NBD; 5) Mrub_2124 …

Bacteria That Resist Centrifugal Force, Nickolas Kessler

Honors Undergraduate Theses

Our lab discovered that approximately 1 in 10,000 Escherichia coli cells in stationary phase remain in suspension after a high g-force centrifuge event. To establish the mechanism behind this curious phenotype, multiple mutant strains of E. coli were independently evolved such that the majority of their populations resisted migration when exposed to high centrifugal forces. Genomic DNA sequencing of the mutants' revealed unique, isolated mutations in genes involved in capsule synthesis and exopolysaccharide (EPS) production. Each mutant exhibits a novel mechanism that allows them to remain in suspension. The mutants were further characterized by determining their growth rates, strengths …

Insights Into Key Gene Regulatory Networks In Borrelia Burgdorferi, William Kenneth Arnold

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Gene regulatory networks are composed of interconnected regulatory nodes created by regulatory factors of multiple types. All organisms finely tune gene expression in order to adapt to and survive within their current niche. Obligate parasitic bacteria are under extreme pressure to quickly and appropriately adapt their gene regulatory programs in order to survive within their given host. Borrelia burgdorferi is one such organism and persists in nature by alternating between two hosts; Ixodes spp. ticks and small vertebrate animals. These two hosts represent drastically different environments; requiring a unique gene regulatory program to survive and transmit between them. Microbiologists have …

Assessment Of A Predicted Diguanylate Cyclase In Treponema Denticola, Dhara T. Patel

Theses and Dissertations

Periodontal disease is a progressive inflammatory condition that is characterized by the reabsorption of alveolar bone, the destruction of connective tissue, and edentulism. It is caused by a dysbiosis in the oral microbiome as a result of a shift from a Gram-positive aerobic bacterial population, to one that becomes more Gram-negative and anaerobic. Treponema denticola is thought to drive this diseased state based on its role as a keystone periopathogen. A major component of T.denticola’s invasiveness is its motility, which allows the spirochete to penetrate and disseminate through tissues. This motility, which has been seen to be crucial to …

Developmental Stage Influences Chromosome Segregation Patterns And Arrangement In The Extremely Polyploid, Giant Bacterium Epulopiscium Sp. Type B, Elizabeth Hutchison

Biology

Few studies have described chromosomal dynamics in bacterial cells with more than two complete chromosome copies or described changes with respect to development in polyploid cells. We examined the arrangement of chromosomal loci in the very large, highly polyploid, uncultivated intestinal symbiont Epulopiscium sp. type B using fluorescent in situ hybridization. We found that in new offspring, chromosome replication origins (oriCs) are arranged in a three-dimensional array throughout the cytoplasm. As development progresses, most oriCs become peripherally located. Siblings within a mother cell have similar numbers of oriCs. When chromosome orientation was assessed in situ by …

Draft Genome Sequence Of Streptomyces Sp. Strain Jv178, A Producer Of Clifednamide-Type Polycyclic Tetramate Macrolactams, Yunci Qi, John M. D’Alessandro, Joshua A.V Blodgett

Biology Faculty Research

Here, we report the draft genome sequence of Streptomyces sp. JV178, a strain originating from Connecticut (USA) garden soil. This strain produces the polycyclic tetramate macrolactam compounds clifednamides A and B. The draft genome contains 10.65 Mb, 9,045 predicted protein coding sequences, and several natural product biosynthetic loci.

Better Living Through Chemistry: Addressing Emerging Antibiotic Resistance, Nathan P. Coussens, Ashley L. Molinaro, Kayla J. Culbertson, Tyler Peryea, Gergely Zahoránszky-Köhalmi, Matthew D. Hall, Dayle A. Daines

Biological Sciences Faculty Publications

The increasing emergence of multidrug-resistant bacteria is recognized as a major threat to human health worldwide. While the use of small molecule antibiotics has enabled many modern medical advances, it has also facilitated the development of resistant organisms. This minireview provides an overview of current small molecule drugs approved by the US Food and Drug Administration (FDA) for use in humans, the unintended consequences of antibiotic use, and the mechanisms that underlie the development of drug resistance. Promising new approaches and strategies to counter antibiotic-resistant bacteria with small molecules are highlighted. However, continued public investment in this area is critical …

Photosynthetic Activity Under Low Light, Danijela Lonco

Williams Honors College, Honors Research Projects

Are bacteria capable of undergoing oxygenic photosynthesis under low-light conditions inside of caves? Inside of an Australian cave, Chlorophyll f was recently discovered. This chlorophyll pigment was found to demonstrate the capability for photosynthesis, suggesting that Chlorophyll f extends the spectrum of usable light needed for oxygenic photosynthesis (Lars, 2015). Due to the findings in this study, a team went to Carlsbad Caverns to see if there were any bacteria capable of undergoing oxygenic photosynthesis under low light.

The Forensic Characterization Of Bacterial And Fungal Organisms In Traditional Chinese Medicine, Julia Grzymkowski, Christopher J. Ehrhardt, Justin L. Poklis, Michelle R. Peace

Undergraduate Research Posters

There has been an increase in use of Traditional Chinese Medicine (TCM) in the United States because they are less expensive and believed to be more effective with less adverse effects in comparison to traditional pharmaceutics. Therefore, sales have increased in the US, despite articles and case studies demonstrating the dangers, such as injury and death, related to TCM, stemming from improper labelling, toxic contaminants, and, in some cases, the presence of pathogenic bacteria. The aim of this study was to perform a survival experiment to demonstrate the importance of proper herbal brewing technique and to conduct a molecular and …

Resolution Of The Nutritional Requirements And Metabolic Profile Of Clostridium Scindens Atcc 35704, A Major Bile Acid-Dehydroxylating Anaerobe In The Human Gut, Rachana Shrestha

Masters Theses

Bile acids (cholate and chenodeoxycholate) are synthesized from cholesterol in the human liver, and secreted in small intestine for food digestion. However, a portion of these primary bile acids is converted in the colon to toxic secondary bile acids, deoxycholate and lithocholate. Secondary bile acid formation is the result of 7α-dehydroxylating anaerobes, and one of the key players in this conversion is Clostridium scindens. Interestingly, little is known about the basic physiology and nutrition of C. scindens. Therefore, the goal of this research was to understand the nutritional requirement, and determine the 7α-dehydroxylation activity and end products from …

Characterization Of Two Cyclic Di-Gmp Phosphodiesterases Hypothesized To Regulate Virulence In Streptomyces Scabies, Madison Flasco

Undergraduate Honors Thesis Projects

Common scab is a devastating disease that affects the marketability of potatoes. The disease results in raised and pitted lesions seen on the surface of the potato and is caused by the soil pathogen, Streptomyces scabies. The S. scabies genome has two cyclic-di-GMP phosphodiesterases, RmdA and RmdB, both regulators of morphology and development. These proteins break down the ubiquitous second messenger molecule cyclic di-GMP, a molecule in charge of cell cycle progression and virulence. Both proteins contain diguanylate cyclase domains and phosphodiesterase domains, GGDEF and EAL, respectively, while RmdA contains an additional PAS_4 domain. Despite similar domain configurations, the two …

Acid Sphingomyelinase Is Essential For Vacuolar Development Of A. Phagocytophilum., Chelsea Cockburn

Theses and Dissertations

Obligate intracellular bacteria are significant causes of morbidity and mortality with over two hundred and fifty million infections worldwide annually. One such bacterium, Anaplasma phagocytophilum is the etiologic agent of human granulocytic anaplasmosis (HGA), a tick-transmitted febrile illness. Previous studies have shown that A. phagocytophilum lacks genes for cholesterol biosynthesis and solely relies on Niemann Pick protein type C (NPC)1-mediated low density lipoprotein (LDL)-derived cholesterol to complete its infection cycle.Acid sphingomyelinase (ASMase) is a lysosomal enzyme that is essential for diverse cellular processes including liberation of LDL-derived cholesterol from the lysosome. By first studying A. phagocytophilum, we found that …

Orientia Tsutsugamushi Modulates Endoplasmic Reticulum Stress To Benefit Its Intracellular Growth And Targets Nlrc5 To Inhibit Major Histocompatibility Complex I Expression, Kyle G. Rodino

Theses and Dissertations

Scrub typhus, caused by the obligate intracellular bacterium Orientia tsutsugamushi, afflicts one million people annually. Despite being a global health threat, little is known about O. tsutsugamushi pathogenesis. Here, we demonstrate that O. tsutsugamushi modulates the ER and ER-associated processes as mechanisms of nutritional virulence and immune evasion. To obtain amino acids to fuel replication, O. tsutsugamushi simultaneously induces ER stress and the unfolded protein response (UPR) while inhibiting ER-associated degradation (ERAD) during early infection time points. During exponential growth, the bacterium releases the ER bottleneck, resulting in generation of ERAD-derived amino acids that it parasitized for replication. …

Comparing The Effectiveness Of Alternative And Prescription Antibiotics Against Gram-Positive Bacteria, Rachel Jenkins, Roan Dickenson, Sam Turnbull, Marcela Torres

Senior Theses

The rapid emergence of antibiotic-resistant bacteria is a global public health concern that threatens the efficacy of antibiotic drugs. We found that natural remedies, specifically coconut oil, honey and cinnamon essential oil, have the potential to be used as a clinical alternative to treat antibiotic-resistant infections. In this experiment, we performed a disk diffusion test and measured the area of inhibition of each treatment to compare the effectiveness of natural and prescription antibiotics. Cinnamon essential oil showed significantly greater antibiotic activity compared to a prescription treatment, amoxicillin. With bacterial resistance continuously expanding, more work needs to be done to determine …

Fluorescence-Reported Allelic Exchange Mutagenesis Reveals A Role For Chlamydia Trachomatis Tmea In Invasion That Is Independent Of Host Ahnak, M. J. Mckuen, Konrad E. Mueller, Y. S. Bae, Kenneth A. Fields

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Development of approaches to genetically manipulate Chlamydia is fostering important advances in understanding pathogenesis. Fluorescence-reported allelic exchange mutagenesis (FRAEM) now enables the complete deletion of specific genes in C. trachomatis L2. We have leveraged this technology to delete the coding sequences for a known type III effector. The evidence provided here indicates that CT694/CTL0063 is a virulence protein involved in chlamydial invasion. Based on our findings, we designate the gene product corresponding to ct694-ctl0063 translocated membrane-associated effector A (TmeA). Deletion of tmeA did not impact development of intracellular chlamydiae. However, the absence of TmeA manifested as a decrease in infectivity …

Type Ix Secretion System: Characterization Of An Effector Protein And An Insight Into The Role Of C-Terminal Domain Dimeration In Outer Membrane Translocation., Lahari Koneru

Electronic Theses and Dissertations

Porphyromonas gingivalis and Tannerella forsythia are two of the primary pathogens that are associated in the etiology and progression of chronic periodontitis. In T. forsythia, KLIKK proteases are the recently identified group of proteolytic enzymes that are secreted through Type IX secretion system (T9SS). Among, these KLIKK proteases a synergistic relationship was observed between karilysin and mirolysin in invading the host complement system for the survival of the bacteria. Since, karilysin has been already characterized, in this study we propose to study about mirolysin through structural, biochemical and biological characterization. The obtained results from the experiments has shown the …

Development Of A Cholera Toxin Cta2/B Based Staphylococcus Aureus Vaccine To Prevent Bovine Mastitis, Neha Misra

Boise State University Theses and Dissertations

Staphylococcus aureus is an important pathogen causing chronic and invasive disease worldwide. This bacterium is a leading cause of community and hospital acquired infections in humans, and is also known to infect wild and domestic animals. Bovine mastitis, or inflammation of the udder, is one of the most economically relevant diseases of the dairy industry, with a high incidence worldwide. S. aureus is a major etiological agent causing this disease. S. aureus mastitis is highly contagious and difficult or impossible to treat. Management practices at dairy farms, that include good sanitation and antibiotic use, have been partially successful in reducing …

Embracing Bacterial Cellulose As A Catalyst For Sustainable Fashion, Luis Quijano

Senior Honors Theses

Bacterial cellulose is a leather-like material produced during the production of Kombucha as a pellicle of bacterial cellulose (SCOBY) using Kombucha SCOBY, water, sugar, and green tea. Through an examination of the bacteria that produces the cellulose pellicle of the interface of the media and the air, currently named Komagataeibacter xylinus, an investigation of the growing process of bacterial cellulose and its uses, an analysis of bacterial cellulose’s properties, and a discussion of its prospects, one can fully grasp bacterial cellulose’s potential in becoming a catalyst for sustainable fashion. By laying the groundwork for further research to be conducted …

Both Adhe And A Separate Nadph-Dependent Alcohol Dehydrogenase Gene, Adha, Are Necessary For High Ethanol Production In Thermoanaerobacterium Saccharolyticum, Tianyong Zheng, Daniel G. Olson, Sean J. Murphy, Xiongjun Shao, Liang Tian, Lee Lynd

Dartmouth Scholarship

Thermoanaerobacterium saccharolyticum has been engineered to produce ethanol at ∼90% theoretical yield and titer of 70 g/L. Its ethanol-producing ability has drawn attention to its metabolic pathways, which could potentially be transferred to other organisms of interest. Here we report that the iron-containing AdhA is important for ethanol production in the high-ethanol strain of T. saccharolyticum (LL1049). A single-gene deletion of adhA in LL1049 reduced ethanol production by ∼50%, whereas multiple gene deletions of all annotated alcohol dehydrogenases except adhA and adhE did not affect ethanol production. Deletion of adhA in wild-type T. saccharolyticum reduced NADPH-linked ADH activity (acetaldehyde-reducing) by …

Defining Electron Bifurcation In The Electron-Transferring Flavoprotein Family, Amaya M. Garcia Costas, Saroj Poudel, Anne-Frances Miller, Gerrit J. Schut, Rhesa N. Ledbetter, Kathryn R. Fixen, Lance C. Seefeldt, Michael W. W. Adams, Caroline S. Harwood, Eric S. Boyd, John W. Peters

Chemistry Faculty Publications

Electron bifurcation is the coupling of exergonic and endergonic redox reactions to simultaneously generate (or utilize) low- and high-potential electrons. It is the third recognized form of energy conservation in biology and was recently described for select electron-transferring flavoproteins (Etfs). Etfs are flavin-containing heterodimers best known for donating electrons derived from fatty acid and amino acid oxidation to an electron transfer respiratory chain via Etf-quinone oxidoreductase. Canonical examples contain a flavin adenine dinucleotide (FAD) that is involved in electron transfer, as well as a non-redox-active AMP. However, Etfs demonstrated to bifurcate electrons contain a second FAD in place of the …

Characterization Of Different Molecular Markers For Identification Of Salmonella Enterica Serovar Typhi In Pakistani Population, Faizan Muttiullah, Fida Muhammad Khan, Fakhar-I- Abbas, Sabiha Shamim

Journal of Bioresource Management

Typhoid is caused by Salmonella enterica serovar Typhi that is usually diagnosed by using serologic and immuno-chromatographic techniques in developing counties including Pakistan, which is thought to be an unreliable diagnostic method. For accurate diagnosis we used molecular techniques to amplify 204 bp StyR-36 and 498 bp flagellin gene for the identification of Salmonella enterica serovar Typhi. This study was done on 58 individuals diagnosed positive of typhoid via serologic tests and 50 healthy individuals as a control group. Success rate of amplification for flagellin gene was 77.58% while that for StyR-36 gene was 68.97% showing that flagellin gene primer …

Characterization Of Porphyromonas Gingivalis Mfa1 Fimbriae., Jae Yong Lee

Electronic Theses and Dissertations

Porphyromonas gingivalis, an obligate anaerobic bacterium associated with chronic periodontitis, utilizes various virulence factors to achieve pathogenicity, one of which is the Mfa1 fimbriae. As a surface structure comprising Mfa1 major subunit along with accessory fimbrial proteins Mfa2-5, the Mfa1 fimbriae has been shown to mediate the adherence of P. gingivalis to antecedent bacterial colonizers of the oral cavity to cause increased virulence. However, the spatial relationships amongst the individual subunits and their assembly mechanism have remained unclear. Through immuno-electron microscopy, Mfa1-4 were localized on the surface of P. gingivalis with Mfa1 localizing throughout the fimbriae and Mfa2 in …

Antimicrobial Hydroxyapatite-Gelatin-Silica Composite Pastes With Tunable Setting Properties, Vuk Uskoković, Shreya Ghosh, Victoria M. Wu

Pharmacy Faculty Articles and Research

Bone grafting is one of the commonest surgical procedures, yet all bone substitutes developed so far suffer from specific weaknesses and the search for a bone graft material with ideal physical and biological properties is still ongoing. Calcium phosphate pastes are the most frequently used synthetic bone grafts, yet they (a) often take an impractically long time to set, (b) release the drug content too fast, and (c) do not form pores large enough to accommodate host cells and foster osseointegration. To make up for these deficiencies, we introduced gelatin and silica to pastes composed of 5–15 nm sized hydroxyapatite …

Geographic Strain Differentiation Of Schistosoma Japonicum In The Philippines Using Microsatellite Markers, Kharleezelle J. Moendeg

Biology Faculty Publications

Background

Microsatellites have been found to be useful in determining genetic diversities of various medically-important parasites which can be used as basis for an effective disease management and control program. In Asia and Africa, the identification of different geographical strains of Schistosoma japonicum, S. haematobium and S. mansoni as determined through microsatellites could pave the way for a better understanding of the transmission epidemiology of the parasite. Thus, the present study aims to apply microsatellite markers in analyzing the populations of S. japonicum from different endemic areas in the Philippines for possible strain differentiation.

Methodology/ Principal …