Bacteriology Commons^™

Microbial, Chemical, And Functional Components In Kefir, Natto, And Feed Ingredients, Dana Mccurdy

All Dissertations

Kefir grains were purchased from online, home kitchen vendors in the United States (n = 22), inoculated into UHT milk, and incubated at 25°C for 22 hours. Results indicated lactobacilli, lactococci and yeast in all samples. Six out of 11 samples contained coliform, and all samples contained pseudomonal and staphylococcal species. Using targeted genome sequencing (16S) of kefir grain samples 1, 2, and 3 revealed that lactobacilli were the predominant genera of bacteria. ITS sequencing revealed different fungal species in each grain. Results indicated potential presence of menaquinone-4 and menaquinone-7 by UPLC-MS/MS analysis.

The fermentation of whole and ground soybeans, …

Analyzing Staphylococcal Contamination On Surfaces And Bedside Areas Of A Neonatal Intensive Care Unit Of A Children's Hospital, Daniel See

Honors Theses

Staphylococci species are known to be a cause of Healthcare-Associated Infections (HAIs) in neonatal intensive care units (NICU). There is limited research about the surveillance and identification of staphylococci bacteria from NICUs. Surveillance of bacteria within the NICU helps to identify areas acting as reservoirs for bacteria so that new cleaning policies and techniques can be put in place to stop the spread of HAIs. The objective of this study was to swab sample sites in a local level IV hospital NICU and identify locations of staphylococci presence throughout the NICU. Forty-one swabs were selected from over 900 swabs collected …

Cyclic Di-Gmp Regulates Motility, Biofilm Formation, And Desiccation Tolerance In Acinetobacter Baumannii, Garrett Reynolds

Electronic Theses and Dissertations

Acinetobacter baumannii is an increasingly multidrug-resistant pathogen contributing to hospital-acquired infections necessitating the discovery of novel treatments. A bacterial second messenger, cyclic diguanosine monophosphate (cyclic di-GMP), can regulate various persistence factors that are potentially advantageous for survival in hospital environments. Cyclic di-GMP–modulating enzymes and cyclic di-GMP–binding effectors predictively are encoded in the Acinetobacter baumannii genome. I hypothesized that cyclic di-GMP controls motility, biofilm formation, and desiccation tolerance in Acinetobacter baumannii. Disrupting cyclic di-GMP–modulating enzymes or cyclic di-GMP–binding effectors should alter the regulatory effectiveness of these phenotypes. I tested the multidrug-resistant isolate Acinetobacter baumannii strain AB5075 and identified several transposon …

Genomic Analysis And Characterization Of Surface Properties Of Naphthalene Degrading Acinetobacter Isolates, Gunn Emilie Berge

Graduate Theses and Dissertations (2019 - present)

No abstract provided.

The Effects Of Short Chain Fatty Acids On Clostridioides Difficile Growth, Sporulation, And Toxin Production, Michelle Baldassare

All Theses

Short chain fatty acids (SCFAs) are products of bacterial fermentation that help maintain important gut functions such as the intestinal barrier, signaling, and immune homeostasis. The main SCFAs acetate, propionate, and butyrate have demonstrated beneficial effects for the host, including importance in combatting infections caused by pathogens such as Clostridioides difficile. C. difficile infection (CDI) is a public health concern and causes 30,000 deaths each year mainly due to the overuse of antibiotics. Despite the potential role of SCFAs in mitigating C. difficile infection, their direct effect on C. difficile remains unclear. Through a set of in-vitro experiments, we …

Using Dietary Additives To Improve Palatability Of Diets Containing Single‐Cell Protein From Methanotrophic Bacteria In Yellowtail Kingfish (Seriola Lalandi) Diets, Luke Pilmer, Lindsey Woolley, Alan J. Lymbery, Michael Salini, Gavin Partridge

Fisheries Research Articles

Single-cell protein (SCP) derived from methanotrophic bacteria has significant potential as a fishmeal alternative in aquafeeds. However, SCP has known palatability issues, to overcome these issues tuna hydrolysate and garlic powder were tested as palatability enhancers against basal diets without these additives. This study tested the inclusion of SCP at four dietary levels of 0%, 10%, 20% and 30%, representing 0%, 25%, 50% and 75% fishmeal replacement in juvenile yellowtail kingfish (Seriola lalandi) (YTK) diets. YTK were fed these diets in triplicate over 35 days. Compared with the control diet, fish fed the SCP10% diet ate less feed, …

Jatropha Tanjorensis A Flora Of Southeast Nigeria: Isolation And Characterization Of Naringenin And Validation Of Bio-Enhanced Synergistical Activity Of Α- Tocopherol Toward Clinical Isolates Of Resistant Bacterial, Ikechukwu Kingsley Ijoma, Vincent Ishmael Egbulefu Ajiwe

Makara Journal of Science

Jatropha tanjorensis is among the rich floras of Southeast Nigeria and used by ethnic people to treat infections and manage health conditions. Ethnomedicine has long been employed in the treatment of ailments caused by bacterial pathogens. Studies showed that the incorporation of synthetic α-tocopherol to an antibacterial agent improves its activity. However, knowledge about the antibacterial-enhanced activity of plant-based α-tocopherols, especially those isolated from Jatropha tanjorensis, is limited because of the different bioactivities of synthetic and natural α-tocopherols. To determine the phytochemicals in J. tanjorensis, we carried out the structural elucidation of its leaf extracts. Naringenin and α-tocopherol …

Presence Of Blaper-1 And Blaveb-1 Beta-Lactamase Genes Among Isolates Of Pseudomonas Aeruginosa From Burn And Trauma Hospital Peshawar, Pakistan, Suleman Khan, Samiyah Tasleem, Alfarah Rehmat Ullah,, Sarwat Moon, Saad Alghamdi, Raina Saad Suliman, Muhammad Ateeq, Muhmmad Salman, Anas S. Dablool,, Banan Atwah, Farkad Bantun

Journal of Bioresource Management

Pseudomonas aeruginosa spp are the most prevalent bacteria that cause nosocomial infections in hospitals. Most antibiotics, including novel new β-lactams, are already resistant to them, and they can become resistant during treatment, which can make the treatment fail. P. aeruginosa isolates from ICU patients who had Per-1 and VEB-1 were the main focus of this study. These two ESBLs are the two most common in ICU patients who had them. 50 isolates were gathered from Peshawar's LRH ICU facilities in the year 2021. The antibiotic susceptibility test was conducted in accordance with the Clinical and Laboratory Standards Institute's standards (CLSI). …

Effect Of Sub-Inhibitory Concentrations Of Nitrofurantoin, Ciprofloxacin And Trimethoprim On In-Vitro Biofilm Formation In Uropathogenic Escherichia Coli, Shane Whelan

ORBioM (Open Research BioSciences Meeting)

The purpose of the current study was to determine the effect of sublethal concentrations of nitrofurantoin, ciprofloxacin and trimethoprim on biofilm formation in 57 uropathogenic Escherichia coli strains (UPEC).

The MIC of nitrofurantoin, ciprofloxacin and trimethoprim was determined for 57 UPEC isolates. Biofilm formation for each isolate with and without sub-lethal concentrations of each antibiotic was then quantified, and the statistical significance of changes in biofilm formation was ascertained by way of a Dunnett's test.

The effects of sub-MIC antibiotics on biofilm formation of UPEC were variable. A total of 22.8% of strains were induced to form biofilm by nitrofurantoin, …

Investigation Of The Urobiome For The Production Of Novel Antimicrobials Against Uropathogenic E. Coli (Upec), Jennifer Jones

ORBioM (Open Research BioSciences Meeting)

BACKGROUND: Urinary tract infections (UTIs) are one of the most common bacterial infections globally with antibiotic treatment becoming increasingly less effective. The urobiome remains a relatively understudied niche as a source of potentially novel antimicrobials (e.g., bacteriocins). Improvements to bacterial culturing and sequencing techniques have highlighted the potentially rich source of alternative treatments and control strategies to target uropathogenic E. coli (UPEC).

MATERIALS AND METHODS: (a) BAGEL 4 was used for bioinformatic screening of the genomes of urobiome isolates to identify bacteriocin gene clusters (BGC).

(b) Expanded quantitative urine culture (EQUC) was used to culture mid-stream urine samples to isolate …

Resolving The Repression Pathway Of Virulence Gene Hila In Salmonella, Alexandra King, Lon Chubiz Phd, Brenda Pratte, Lauren Daugherty

Undergraduate Research Symposium

Salmonella is a relatively abundant, virulent species of bacteria that is most known for spreading gastrointestinal diseases through food. These illnesses result in approximately 1.35 million infections, including over 25,000 hospitalizations each year, in the U.S. alone (CDC.gov). As antibiotic resistance becomes an increasingly urgent public health problem, the importance of developing alternative treatment methods is only becoming more crucial. One of the genes responsible for this virulence is known as hilA. HilA is the main transcriptional regulator of Salmonella Pathogenicity Island-1 gene (UniProt). SPI-1 plays an important role in the invasion of Salmonella into epithelial cells. The proteins encoded …

The Interaction Of Sulfate And Perchlorate And Its Implications On Bacterial Survival On Mars, Jack M. Richardson, Dylan Clark, Karly Kenny

2022 Symposium

Escherichia coli, Bacillus subtilis, and Staphylococcus aureus are all known spacecraft contaminants. This makes their viability to arrive and survive on Mars feasible, however, this could prove to be a great risk to the Martian environment. In order to test this possibility, all three species were grown within brines containing differing salts and salt concentrations. These salts and their corresponding concentrations are based on known data regarding Martian soil. Growth was measured over a course of 20 hours in solutions containing MgSO₄ at concentrations of 4.6% and 9.2%, Mg(ClO₄)₂ at concentrations of 0.6% and …

Assessing The Activity Of Antimicrobial Peptides Against Common Marine Bacteria Located In Rotifer (Brachionus Plicatilis) Cultures, Chelsea Woods, Lindsey Woolley, Gavin Partridge, Mengqi Chen, Evan F. Haney, Robert E.W. Hancock, Nicky Buller, Andrew Currie

Fisheries Research Articles

Rotifers are used as the first feed for marine fish larvae and are grown in large cultures that have high loads of organic matter and heterotrophic bacteria; these bacteria are passed on to the developing fish larvae and can potentially lead to bacterial infections. A modified minimum inhibitory concentration (MIC) protocol for antimicrobial peptides was used to determine the potency of ten antimicrobial peptides (AMPs) in artificial seawater relevant to a rotifer culture (salinity of 25‰) against common marine pathogens. All of the AMPs had antimicrobial activity against the bacterial isolates when the salt concentration was approximately zero. However, in …

An Investigation On The Impact Of Intestinal Oxygen Availability On Survival And Regulation Of Virulence In Listeria Monocytogenes, Damayanti Chakravarty

Dissertations

The deadly foodborne pathogen Listeria monocytogenes is a gram positive facultative anaerobic bacterium. It is the third leading cause of death from food-borne illnesses. Once ingested, it encounters various stressors in the gastrointestinal (GI) tract, including acidic pH, bile, and alterations in oxygen availability. Various studies have been done regarding the pathogen’s survival mechanism against acid and bile. Since the lower parts of the GI tract are anaerobic, it is imperative to investigate how physiologically relevant anaerobic conditions impact L. monocytogenes’s survival. Transcriptomic analysis of L. monocytogenes under conditions mimicking the GI tract was performed. A large number of genes …

Parameter Estimation Using Nudging On The Logistic Growth Equation, Susan Rogowski

Biology and Medicine Through Mathematics Conference

No abstract provided.

Characterization Of A Helicobacter Pylori Small Rna By Rt-Pcr, Roxanne Mcpeck, Andrea Castillo

2022 Symposium

Helicobacter pylori, a bacterial gastric pathogen infecting approximately 50% of the human population, produces gastritis, ulcers, and gastric cancers. Colonizing the inhospitable and fluctuating environment in the stomach requires tight genetic control. However, H. pylori lacks many genetic regulatory elements present in other bacteria to control gene expression. Instead, over 200 small RNAs (sRNAs; noncoding RNAs shorter than 300 nucleotides) have been found in this bacterium, but few have been fully characterized. Of those, many are antisense to virulence genes. Characterizing these sRNAs is important in understanding the mechanisms of molecular genetics and potentially supporting medical management of this …

Eskape Pathogens: The Clinical Prevalence And Molecular Mechanisms Of Antibiotic Resistance, Anusha Attre

Honors Scholar Theses

The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) are the leading cause of all nosocomial, or healthcare-associated (HAI), infections (Navidinia, 2016). The purpose of this research study is to determine the burden of ESKAPE infections on healthcare and study the antibiotic resistance in these high-risk pathogens to provide direction for researchers to develop new antimicrobial innovations to reduce ESKAPE infectivity and improve patient outcomes. To study the burden of ESKAPE infections, this review analyzes the current statistics explaining the clinical prevalence of each pathogen in causing HAIs. Additionally, each pathogen is …

Antibiotic-Resistant Bacteria In Freshwater Crayfish, Colby Finch

Honors Theses

The presence of antibiotic-resistant bacteria is increasing in natural aquatic environments. Alongside this, organisms that live in these ecosystems are increasingly harboring antibiotic-resistant bacteria. In this study, I analyzed the capacity for the crayfish species Procambarus vioscai paynei to harbor antibiotic-resistant bacteria. Crayfish, as well as water and sediment, were sampled from a pond at the University of Mississippi Field Station. The guts of crayfish were plated on TSA agar, as well as agar containing vancomycin, erythromycin, penicillin, tetracycline, or ciprofloxacin. Following incubation, counts of bacteria were determined. Selected bacterial isolates were tested for multiple antibiotic-resistance. Bacterial isolates were also …

Studying The Lysine Acetylation Of Aconitase Isozymes In E. Coli, Sara Ottinger

Chemistry & Biochemistry Undergraduate Honors Theses

The contents of this thesis have been modified from the publication “Araujo J, Ottinger S, Venkat S, Gan Q and Fan C (2022) Studying Acetylation of Aconitase Isozymes by Genetic Code Expansion. Front. Chem. 10:862483”. Though studies have found multiple lysine sites in which acetylation takes place in Escherichia Coli aconitase, acetylation’s effects on the enzyme’s activity have yet to be studied. Aconitase is the dehydratase-hydratase found in the citric acid and glyoxylate cycles responsible for the reversible isomerization of citrate to isocitrate via cis-aconitate intermediate. There are two isoforms of aconitase in E. coli: AcnA and AcnB. In …

Aggregatibacter Actinomycetemcomitans Exploits And Modulates The Immune Response By Human Neutrophils For Survival In The Anaerobic Environment., Hazel Ozuna

Electronic Theses and Dissertations

Aggregatibacter actinomycetemcomitans (Aa) is a Gram-negative facultative anaerobe and an opportunistic oral pathogen, strongly associated with localized periodontitis and other inflammatory diseases. Periodontitis is a chronic inflammation of the periodontium resulting from the inflammatory response of the host towards the dysbiotic microbial community present at the gingival crevice. The host immune response creates a hostile environment for microorganisms; therefore, it is important for Aa to be able to regulate the necessary genes to survive and thrive in such an environment. Aaexpresses several virulence factors such as a cytolethal distending toxin (Cdt), lipopolysaccharide (LPS) and leukotoxin A (LtxA), …