Characterization Of Type Ii Toxin Anti-Toxin Systems In Aggregatibacter Actinomycetemcomitans.,
2018
University of Louisville
Characterization Of Type Ii Toxin Anti-Toxin Systems In Aggregatibacter Actinomycetemcomitans., Blair W. Schneider
Electronic Theses and Dissertations
Microbes express many protective mechanisms in response to environmental stress. Toxin/anti-toxin systems encode a biologically active toxin and a labile anti-toxin that inhibits the toxin’s activity. These systems are known to contribute to persister cell and biofilm formation. A. actinomycetemcomitans thrives in the complex oral microbial community and is subjected to continual environmental flux. Little is known regarding the presence and function of TA systems in this organism or their contribution survival in the oral environment. Using BLAST searches and other informatics tools, we identified 11 intact TA systems that are conserved across all seven serotypes of A. actinomycetemcomitans and …
Regulation Of The Tubulin Homolog Ftsz In Escherichia Coli,
2018
CUNY Graduate Center
Regulation Of The Tubulin Homolog Ftsz In Escherichia Coli, Monika S. Buczek
Dissertations, Theses, and Capstone Projects
Escherichia coli is a well-known pathogen, and importantly, a widely used model organism in all fields of biological sciences for cloning, protein purification, and as a model for Gram-negative bacterial species. And yet, researchers do not fully understand how this bacterium replicates and divides. Every year additional division proteins are discovered, which adds complexity to how we understand E. coli undergoes cell division. Due to their specific roles in cytokinesis, some of these proteins may be potential targets for development of antibacterials or bacteriostatics, which are much needed for fighting the current global antibacterial deficit. My thesis work focuses on …
Functional Similarity Of Prd-Containing Virulence Regulators In Bacillus Anthracis,
2018
The University of Texas M D Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences
Functional Similarity Of Prd-Containing Virulence Regulators In Bacillus Anthracis, Malik Raynor
Dissertations and Theses (Open Access)
Bacillus anthracis produces three regulators, AtxA, AcpA, and AcpB, that control virulence gene expression and are members of an emerging class of regulators termed “PCVRs” (Phosphoenolpyruvate-dependent phosphotransferase regulation Domain-Containing Virulence Regulators). AtxA controls expression of the toxin genes; lef, cya, and pag, and is the master virulence regulator and archetype PCVR. AcpA and AcpB are less well studied. AcpA and AcpB independently positively control transcription of the capsule biosynthetic operon capBCADE, and culture conditions that enhance AtxA activity result in capBCADE transcription in strains lacking acpA and acpB. RNA-Seq was used to assess the regulons of the …
Microbiome Of Commercial Broilers Through Evisceration And Immersion Chilling,
2018
University of Arkansas, Fayetteville
Microbiome Of Commercial Broilers Through Evisceration And Immersion Chilling, John A. Handley
Graduate Theses and Dissertations
The United States poultry industry generated 38.6 billion pounds (17,500 metric ton) of meat in 2014 which averaged to 121 pounds (55 kg) per individual of the U.S that same year. Of that meat generated by the poultry industry, an estimated 1 million cases of Salmonellosis will occur. Out of the 1 million cases approximately 40, 000 to 50,000 will be confirmed cases by the CDC. Recently, the USDA has requested changes in the inspection process and are currently allowing processors more freedom to utilize innovation to drive the increase in safer and more desirable foods. The new standards set …
Bioprospecting Deep-Sea Actinobacteria For Novel Anti-Infective Natural Products,
2018
Florida Atlantic University
Bioprospecting Deep-Sea Actinobacteria For Novel Anti-Infective Natural Products, Dongbo Xu, Linna Han, Chunhui Li, Qi Cao, Duolong Zhu, Nolan H. Barrett, Dedra Harmody, Jing Chen, Haining Zhu, Peter J. Mccarthy, Xingmin Sun, Guojun Wang
Molecular and Cellular Biochemistry Faculty Publications
The global prevalence of drug resistance has created an urgent need for the discovery of novel anti-infective drugs. The major source of antibiotics in current clinical practice is terrestrial actinobacteria; the less-exploited deep-sea actinobacteria may serve as an unprecedented source of novel natural products. In this study, we evaluated 50 actinobacteria strains derived from diverse deep water sponges and environmental niches for their anti-microbial activities against a panel of pathogens including Candida albicans, Clostridium difficile, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA), and Pseudomonas aeruginosa. More than half of the tested strains (27) were identified as …
2018 3rd Place: The Growth And Characterization Of Psychromonas Aquimarina, A New Model Organism For Climate Change,
2018
Harrisburg University of Science and Technology
2018 3rd Place: The Growth And Characterization Of Psychromonas Aquimarina, A New Model Organism For Climate Change, Carrie Carpenter, Catherine Santai
Harrisburg University Research Symposium (2018 & 2019)
Climate change is currently affecting the Earth and will only increase with time1. A change to the environment means that wildlife will need to adapt. Adaptation occurs when an organism changes physiologically or otherwise to permit continued growth in the environment in which it resides. Scientists do not completely understand adaptation mechanisms. Psychromonas aquimarinais a novel bacterium, with little known. This bacteria will first be characterized and studied before conducting temperature studies. Psychromonas aquimarina is a psychrophile, a bacterium able to survive in colder regions where most bacteria would not. P. aquimarinais an ideal bacterium to study because climate change …
Characterization Of The Interaction Between R. Conorii And Human Host Vitronectin In Rickettsial Pathogenesis,
2018
Louisiana State University and Agricultural and Mechanical College
Characterization Of The Interaction Between R. Conorii And Human Host Vitronectin In Rickettsial Pathogenesis, Abigail Inez Fish
LSU Doctoral Dissertations
Spotted Fever Group Rickettsia are inoculated into the mammalian host during hematophagous arthropod feeding. Once in the bloodstream and during dissemination, the survival of these pathogens is dependent upon their ability to evade innate host defenses until a proper cellular target is reached. The establishment of a successful infection also relies on the ability of the bacteria to attach and invade target cells, as failure to do so results in destruction of the bacterium. Rickettsia conorii expresses an outer membrane protein, Adr1, which binds the multifunctional human glycoprotein, vitronectin, to promote resistance to complement mediated killing. Homologs of Adr1 are …
Discovery Of Geographical Gene Variants In Related Pseudomonas Aeruginosa Bacteriophages,
2018
Brigham Young University - Provo
Discovery Of Geographical Gene Variants In Related Pseudomonas Aeruginosa Bacteriophages, Emilee Carr, Elise Melhado, Emily Loertscher, Trever Thurgood, Ruchira Sharma, Julianne H. Grose
Library/Life Sciences Undergraduate Poster Competition 2019
Antibiotic resistant bacterial strains are a major crisis in the world due to the difficult nature of curing individuals afflicted with them. Phage therapy has been proposed as an alternate treatment for these bacterium. In Dr. Julianne Grose's lab, bacteriophages were against the bacteria, Pseudomonas aeruginosa. To isolate, environmental samples were utilized in enrichment cultures that were ultimately used in serial dilutions, plaque purification, electron microscopy, DNA isolation, sequencing, and genome annotation. The P. aeruginosa phage, TF17, infects a bacterial strain that is highly related to a strain that causes fatalities as an opportunistic infection in patients with cystic fibrosis. …
Characterization Of Pinitol Catabolism In Sinorhizobium Meliloti And Its Role In Nodule Occupancy,
2018
Western Michigan University
Characterization Of Pinitol Catabolism In Sinorhizobium Meliloti And Its Role In Nodule Occupancy, Angela Irene Kennedy-Mendez
Masters Theses
Sinorhizobium meliloti, which is the nitrogen fixing symbiont of Medicago sativa (alfalfa), was used to test the hypothesis that D-chiro-inositol is an intermediate of pinitol catabolism and that pinitol catabolism plays a role in S. melilot s ability to compete for nodule occupancy. An analytical method, involving gas chromatography and mass spectrometry (GCMS), was developed to detect and separate pinitol and D-chiro-inositol. The S. meliloti wild type, and three isogenic mutant strains (idhA, mocD, and mocE) were grown in minimal medium with pinitol and pinitol plus glycerol. The S. meliloti wild type can utilize pinitol as a sole carbon source, …
In Vitro Assay Development As An Alternative To The Use Of Laboratory Animals For Measuring Clostridium Perfingens Type C Toxoid,
2018
University of Nebraska-Lincoln
In Vitro Assay Development As An Alternative To The Use Of Laboratory Animals For Measuring Clostridium Perfingens Type C Toxoid, Lauren M. Wilmes
School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research
Clostridium perfringens type C produces beta toxin, which is a primary virulence determinate that can cause necrotic enteritis in neonatal animals. Vaccines directed against C. perfringens toxins have shown to be efficacious in preventing disease. However, the production of a commercial vaccine requires not only an efficacious antigen, but also testing methods for quantifying antigens and potency on final product. This research was undertaken to fulfill a need for the reduction in small animal usage to produce and deliver vaccines. The current testing methods are performed in vivo according to the Code of Federal Regulations number 9 (9CFR) United …
Characterization Of Silicon Ion Exposure On Deinococcus Radiodurans,
2018
Air Force Institute of Technology
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,
2018
University of Nebraska-Lincoln
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,
2018
Loyola University Chicago
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,
2018
Tennessee State University
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,
2018
Old Dominion University
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,
2018
Bowling Green State University
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,
2018
Augustana College, Rock Island Illinois
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,
2018
University of Central Florida
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,
2018
University of Kentucky
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,
2018
Virginia Commonwealth University
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 …
