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Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey 2019 Eastern Illinois University

Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey

Masters Theses

The occurrence and spread of antibiotic-resistant genes (ARGs) are pressing public health problems worldwide. A key factor contributing to the spread of ARGs is lateral gene transfer. Wastewater treatment plants (WWTPs) are measured hot spots of microbial diversity and resistance because they receive polluted wastewater from diverse sources and contain a variety of different environments with dense bacterial loads. Due to the overuse of antibiotics the genetic capacities of microbes have profited. This helps every source of resistance gene and every means of horizontal gene transmission to develop the multiple mechanism of resistance to each antibiotic used clinically, agriculturally, or ...


Changes In Soil Microbiology Under Conventional And No-Till Production During Crop Rotation, C. J. Hsiao, G. F. Sassenrath, L. Zeglin, G. Hettiarachchi, C. Rice 2019 Kansas State University

Changes In Soil Microbiology Under Conventional And No-Till Production During Crop Rotation, C. J. Hsiao, G. F. Sassenrath, L. Zeglin, G. Hettiarachchi, C. Rice

Kansas Agricultural Experiment Station Research Reports

Soil microbial activity is important for crop production. Soil microbes are involved in nutrient and water cycling within the soil, and interact with crop plants to provide the basic nutrient and water resources needed for crop production. Claypan soils have unique physical characteristics that impact soil biology. This study explored the tempo­ral changes in soil microbiology in a claypan soil under conventional and no-till produc­tion during a crop rotation of corn/winter wheat/soybean/fallow commonly planted in southeast Kansas. We found soil microbial activity changed more in the top two inches of soil than in the lower ...


Methods Of Testing Skin Mucosomes Of Anaxyrus Boreas In The Face Of Batrachocytrium Dendrobatidis, Gena Rumsey 2019 University of Colorado, Boulder

Methods Of Testing Skin Mucosomes Of Anaxyrus Boreas In The Face Of Batrachocytrium Dendrobatidis, Gena Rumsey

Undergraduate Honors Theses

The microbial community of amphibians skin has demonstrated significant importance in amphibian health and disease resistance specifically in response to the pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd; Barnhart et al. 2017). Since its discovery in the late 1990s, Bd has contributed to world-wide decline in amphibian populations. Multiple naturally occurring amphibian-skin bacteria have been identified as inhibitors of Bd, including Janthinobacterium lividum (J liv; Harris et al. 2009). The McKenzie group developed a probiotic treatment of J liv as an intervention for a boreal toad population in Colorado drastically declining due to a Bd epidemic. Since wild toads cannot be ...


Temporal Dynamics Of Bacterial Communities In Soil And Leachate Water After Swine Manure Application, Elizabeth L. Rieke, Michelle L. Soupir, Thomas B. Moorman, Fan Yang, Adina C. Howe 2018 Iowa State University

Temporal Dynamics Of Bacterial Communities In Soil And Leachate Water After Swine Manure Application, Elizabeth L. Rieke, Michelle L. Soupir, Thomas B. Moorman, Fan Yang, Adina C. Howe

Agricultural and Biosystems Engineering Publications

Application of swine manure to agricultural land allows recycling of plant nutrients, but excess nitrate, phosphorus and fecal bacteria impact surface and drainage water quality. While agronomic and water quality impacts are well studied, little is known about the impact of swine manure slurry on soil microbial communities. We applied swine manure to intact soil columns collected from plots maintained under chisel plow or no-till with corn and soybean rotation. Targeted 16S-rRNA gene sequencing was used to characterize and to identify shifts in bacterial communities in soil over 108 days after swine manure application. In addition, six simulated rainfalls were ...


Efficacy Of A T Cell-Biased Adenovirus Vector As A Zika Virus Vaccine, Brianna L. Bullard, Brigette N. Corder, Matthew J. Gorman, Michael S. Diamond, Eric A. Weaver 2018 University of Nebraska - Lincoln

Efficacy Of A T Cell-Biased Adenovirus Vector As A Zika Virus Vaccine, Brianna L. Bullard, Brigette N. Corder, Matthew J. Gorman, Michael S. Diamond, Eric A. Weaver

Virology Papers

Zika virus (ZIKV) is a major public health concern due to the risk of congenital Zika syndrome in developing fetuses and Guillain-Barre syndrome in adults. Currently, there are no approved vaccines available to protect against infection. Adenoviruses are safe and highly immunogenic vaccine vectors capable of inducing lasting humoral and cellular immune responses. Here, we developed two Adenovirus (Ad) vectored Zika virus vaccines by inserting a ZIKV prM-E gene expression cassette into human Ad types 4 (Ad4-prM-E) and 5 (Ad5-prM-E). Immune correlates indicate that Ad5-prM-E vaccination induces both an anti-ZIKV antibody and T-cell responses whereas Ad4-prM-E vaccination only induces a ...


Orbit: A New Paradigm For Genetic Engineering Of Mycobacterial Chromosomes, Kenan C. Murphy, Samantha J. Nelson, Subhalaxmi Nambi, Kadamba Papavinasasundaram, Christina E. Baer, Christopher M. Sassetti 2018 University of Massachusetts Medical School

Orbit: A New Paradigm For Genetic Engineering Of Mycobacterial Chromosomes, Kenan C. Murphy, Samantha J. Nelson, Subhalaxmi Nambi, Kadamba Papavinasasundaram, Christina E. Baer, Christopher M. Sassetti

Open Access Articles

Two efficient recombination systems were combined to produce a versatile method for chromosomal engineering that obviates the need to prepare double-stranded DNA (dsDNA) recombination substrates. A synthetic "targeting oligonucleotide" is incorporated into the chromosome via homologous recombination mediated by the phage Che9c RecT annealase. This oligonucleotide contains a site-specific recombination site for the directional Bxb1 integrase (Int), which allows the simultaneous integration of a "payload plasmid" that contains a cognate recombination site and a selectable marker. The targeting oligonucleotide and payload plasmid are cotransformed into a RecT- and Int-expressing strain, and drug-resistant homologous recombinants are selected in a single step ...


The Effects Of Inulin And Galactooligosaccharides On The Production Of Reuterin By Lactobacillus Reuteri, Micah Dwight Forshee 2018 Olivet Nazarene University

The Effects Of Inulin And Galactooligosaccharides On The Production Of Reuterin By Lactobacillus Reuteri, Micah Dwight Forshee

ELAIA

The microbiome is a dynamic community that can positively and negatively influence host health. Lactobacillus reuteri is a probiotic that has received much attention for its ability to inhibit pathogens such as Salmonella typhimurium, Escherichia coli, and Clostridium difficile. It does so by its unique ability to metabolize glycerol into the antimicrobial compound 3-HPA, which is commonly referred to as reuterin. The ability to secrete reuterin is dependent not only on glycerol availability but also the concentration of glucose. In fact, there appears to be a “goldilocks” ratio between glucose and glycerol as either too much or too little glucose ...


Antibiotic Resistance Coming Soon To A Pathogen Near You, McKenzie Altman, Tamia Mills, Lindsey Layman, Catherine Stone 2018 Marian University

Antibiotic Resistance Coming Soon To A Pathogen Near You, Mckenzie Altman, Tamia Mills, Lindsey Layman, Catherine Stone

Undergraduate Research Symposium (URS)

The phenomena of antibiotic resistant bacteria has increased worldwide and can frequently be found on everyday surfaces. Here, we characterize a bacterial isolate from a woman’s restroom door handle at Marian. Preliminary results comprised of morphological and biochemical tests, including growth characteristics on blood agar medium, as well as usage of the Kirby Bauer agar diffusion test to determine antibiotic susceptibility, identifies this isolate to be a multidrug resistant Neisseria species. However, additional detailed analysis is needed to confirm its identity.


Investigating The Impact Of Oxidative Stress On Tetrahymena Thermophila Sirtuin,Thd 18, Emmanuel Dubuisson 2018 CUNY New York City College of Technology

Investigating The Impact Of Oxidative Stress On Tetrahymena Thermophila Sirtuin,Thd 18, Emmanuel Dubuisson

Publications and Research

Sirtuins are a family of enzymes that fulfill various important biological functions. Investigators have looked for the implication of Sirtuin genes in cell signaling mechanisms, in the formation and silencing of heterochromatin, in the regulation of ion channels, and in the modulation of the cellular redox reactions[2]. Different model organisms have been previously used to conduct these studies; among them, there are yeasts, nematodes, and fruit flies. Each one has made some valuable contribution into the vast body of knowledge related to this field.

However, gaps in the understanding of Sirtuins functions still remain to be filled. In this ...


Potent Cas9 Inhibition In Bacterial And Human Cells By Acriic4 And Acriic5 Anti-Crispr Proteins, Jooyoung Lee, Aamir Mir, Alireza Edraki, Bianca Garcia, Nadia Amrani, Hannah E. Lou, Ildar Gainetdinov, April Pawluk, Raed Ibraheim, Xin D. Gao, Pengpeng Liu, Alan R. Davidson, Karen L. Maxwell, Erik J. Sontheimer 2018 University of Massachusetts Medical School

Potent Cas9 Inhibition In Bacterial And Human Cells By Acriic4 And Acriic5 Anti-Crispr Proteins, Jooyoung Lee, Aamir Mir, Alireza Edraki, Bianca Garcia, Nadia Amrani, Hannah E. Lou, Ildar Gainetdinov, April Pawluk, Raed Ibraheim, Xin D. Gao, Pengpeng Liu, Alan R. Davidson, Karen L. Maxwell, Erik J. Sontheimer

Open Access Articles

In their natural settings, CRISPR-Cas systems play crucial roles in bacterial and archaeal adaptive immunity to protect against phages and other mobile genetic elements, and they are also widely used as genome engineering technologies. Previously we discovered bacteriophage-encoded Cas9-specific anti-CRISPR (Acr) proteins that serve as countermeasures against host bacterial immunity by inactivating their CRISPR-Cas systems (A. Pawluk, N. Amrani, Y. Zhang, B. Garcia, et al., Cell 167:1829-1838.e9, 2016, https://doi.org/10.1016/j.cell.2016.11.017). We hypothesized that the evolutionary advantages conferred by anti-CRISPRs would drive the widespread occurrence of these proteins in nature (K ...


Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern 2018 University of Arkansas, Fayetteville

Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern

Biological Sciences Undergraduate Honors Theses

Methanogens, some of Earth’s most primitive prokaryotic organisms, are candidates for possible life forms capable of inhabiting Mars. Specifically, four different species (Methanobacterium formicicum, Methanococcus maripaludis, Methanosarcina barkeri, Methanothermobacter wolfeii) were analyzed for their tolerance to the presence of illite clay. Illite is a crystalline mineral that has been identified from regions of Mars’s surface. Results indicated that all four species grew with some success in the illite at different concentrations. This experimentation with methanogens’ abilities to survive and reproduce in the presence of illite allows for a more accurate understanding of the potential capability of microbial growth ...


Synthesis And Characterization Of Targeted Bar Encapsulated Polylactic-Co-Glycolic Acid Nanoparticles To Inhibit Porphyromonas Gingivalis Biofilm Formation., Ranjith Radha Krishnan 2018 University of Louisville

Synthesis And Characterization Of Targeted Bar Encapsulated Polylactic-Co-Glycolic Acid Nanoparticles To Inhibit Porphyromonas Gingivalis Biofilm Formation., Ranjith Radha Krishnan

Electronic Theses and Dissertations

Periodontal disease is one of the most prevalent infectious diseases worldwide. Between 30-50% of the global adult population suffers from periodontal disease. Some form of periodontitis is present in 46% of American adults, corresponding to annual expenditures in excess of 14 billion dollars for treatment and prevention. Current treatments for periodontal diseases involve mechanical removal of plaque, correction of risk factors, gingival surgery and/or antibiotic therapy. To our knowledge there is no effective therapeutic approach that aims to limit pathogen colonization of the oral biofilm or re-colonization after treatment. Interaction of the pathogen Porphyromonas gingivalis with oral streptococci is ...


Virulence Regulation In Pseudomonas Aeruginosa Via The Alginate Regulators, Algu And Algr, The Posttranscriptional Regulator, Rsma, And The Two-Component System, Algz/R, Sean Stacey 2018 East Tennessee State Universtiy

Virulence Regulation In Pseudomonas Aeruginosa Via The Alginate Regulators, Algu And Algr, The Posttranscriptional Regulator, Rsma, And The Two-Component System, Algz/R, Sean Stacey

Electronic Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative bacillus able to colonize a wide variety of environments. In the human host, P. aeruginosa can establish an acute infection or persist and create a chronic infection. P. aeruginosa is able to establish a niche and persist in human hosts by using a wide array of virulence factors used for: movement, killing host cells, and evading immune cells and antibiotics. Understanding virulence factors and their regulation has proved to be an important means of combating the morbidity and mortality of P. aeruginosa as well as the ever-increasing threat of drug resistance. By targeting virulence factors ...


Aqueous Ozone Inactivation Of Viruses And Bacteria On Biotic And Abiotic Surfaces, Cailin Dawley 2018 University of Arkansas, Fayetteville

Aqueous Ozone Inactivation Of Viruses And Bacteria On Biotic And Abiotic Surfaces, Cailin Dawley

Theses and Dissertations

Produce is susceptible to contamination by foodborne pathogens. Food service establishments utilize sanitizing agents to reduce microbes on produce surfaces. The research objectives were to evaluate the efficacy of aqueous ozone 1) on the inactivation of viruses and bacteria on produce; 2) on the inactivation of viruses on stainless steel; and 3) against viruses in association with bacteria on produce surfaces. For objective 1, Boston bibb lettuce and cherry tomatoes were spot inoculated with a cocktail of viruses (murine norovirus (MNV) and MS2 bacteriophage) or bacteria (Enterobacter cloacae and Bacillus cereus) and washed for 40 min with samples taken every ...


Assessment Of Salmonella Enterica Biofilms And Expression Differences Among Serovars, Zhaohao Shi 2018 University of Arkansas, Fayetteville

Assessment Of Salmonella Enterica Biofilms And Expression Differences Among Serovars, Zhaohao Shi

Theses and Dissertations

Biofilms are communities of microorganisms associated by a matrix of extracellular polymers. In this state, microorganisms occupy an ecological niche distinct from their free-floating, planktonic counterparts. Also, biofilm bacteria become biologically unique as they form communities and lose motility. The acquisition of these physiological attributes enables the biofilm to persist through harsh environmental conditions, including antimicrobial induced stress and to resist sanitization efforts. Because of these features, biofilms can rapidly disseminate across numerous surfaces and as they establish, become challenging to remove. This is a particular issue for the food industry as processing plants offer favorable conditions for biofilm formation ...


The Antimicrobial Properties Of Honey And Their Effect On Pathogenic Bacteria, Shreena Himanshu Mody 2018 Brigham Young University

The Antimicrobial Properties Of Honey And Their Effect On Pathogenic Bacteria, Shreena Himanshu Mody

All Theses and Dissertations

Honey has been used to heal wounds since ancient times. There are many references in ancient literature that cite honey for its medicinal uses. It is used as an alternative agent to cure infections of wounds, burns, ulcers etc. Researchers have shown some of the antimicrobial properties of honey when used as an ointment. When applied to an affected area, it helps to promote the growth of healthy tissue. One of the factors on which the quality of the honey depends, is its geographical origin. Based on the location, honey types can vary as much as 100-fold from each other ...


Galleria Mellonella As An Alternate Infection Model For Burkholderia Species And A Comparison Of Suspension And Surface Test Methods For Evaluating Sporicidal Efficacy, Joseph D. Thiriot 2018 Brigham Young University

Galleria Mellonella As An Alternate Infection Model For Burkholderia Species And A Comparison Of Suspension And Surface Test Methods For Evaluating Sporicidal Efficacy, Joseph D. Thiriot

All Theses and Dissertations

Melioidosis is a neglected tropical disease that continues unabated in many countries, particularly in Southeast Asia. There is no vaccine and antimicrobial treatment is expensive and complicated. Virulence models are important tools used to investigate genes involved in pathogenesis. Galleria mellonella is the larvae of the wax worm moth that has been used to model various infections. Based on previous studies, we attempted to establish an infection model using Burkholderia pseudomallei and Burkholderia thailandensis, a related species which is avirulent in humans. Injections of various forms of these species (fresh and frozen) were used to develop Kaplan-Meier plots. We also ...


Semen Exosomes: Intrinsic Inhibitors Of Hiv-1 Infection, Jennifer Lynn Welch 2018 University of Iowa

Semen Exosomes: Intrinsic Inhibitors Of Hiv-1 Infection, Jennifer Lynn Welch

Theses and Dissertations

Exosomes are cell-derived vesicles that circulate in bio-fluids and enclose cell-associated cargo, producing various consequences in intercellular communication and may contribute to microbial pathogenesis. Exosomes are similar in composition to enveloped viruses, making differentiation between exosomes and enveloped viruses difficult. Yet, exosomes and enveloped viruses may vary considerably in function. Exosomes produced from infected cells may incorporate viral material as they are simultaneously produced with viruses and depending upon the cargo, contribute to disease pathogenesis. Conversely, exosomes from uninfected cells may contribute to protection from infection. Exosomes from breast milk, vaginal fluid, and semen of healthy donors protect against HIV-1 ...


Metagenomic Insights Into The Degradation Of Resistant Starch By Human Gut Microbiota, Marius Vital, Adina Howe, Nathalie Bergeron, Ronald M. Krauss, Janet K. Jansson, James M. Tiedje 2018 Michigan State University

Metagenomic Insights Into The Degradation Of Resistant Starch By Human Gut Microbiota, Marius Vital, Adina Howe, Nathalie Bergeron, Ronald M. Krauss, Janet K. Jansson, James M. Tiedje

Agricultural and Biosystems Engineering Publications

Several studies monitoring alterations in the community structure upon resistant starch (RS) interventions are available, although comprehensive function-based analyses are lacking. Recently, a multiomics approach based on 16S rRNA gene sequencing, metaproteomics, and metabolomics on fecal samples from individuals subjected to high and low doses of type 2 RS (RS2; 48 g and 3 g/2,500 kcal, respectively, daily for 2 weeks) in a crossover intervention experiment was performed. In the present study, we did pathway-based metagenomic analyses on samples from a subset of individuals (n = 12) from that study to obtain additional detailed insights into the functional structure ...


Bacterial Abundance And Resistance In Ground Beef Varieties, Savannah Kumar, Sarah M. Boomer 2018 Western Oregon University

Bacterial Abundance And Resistance In Ground Beef Varieties, Savannah Kumar, Sarah M. Boomer

PURE Insights

Raw ground beef purchased at supermarkets across America have one thing in common: they harbor bacteria, some of which are drug resistant and can be detrimental to public health. To understand the impact of farming and processing practices on the quantity of bacteria and drug resistance, organic and regular beef were assessed using MacConkey media. Bacterial colonies were sorted according to lactose utilization, with positive colonies representing fecal E. coli. Lactose negative colonies were further characterized into one of two groups (fecal Hafnia-like or soil Pseudomonas) using a variety of metabolic tests (oxidase, sulfur, indole). Advanced metabolic testing showed that ...


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