Bacteriology Commons^™

Occurrence Of Kanamycin-Resistant Bacteria Relative To Anthropogenic Pollution Along Richland Creek In Nashville, Tn​, Jolene Ho Mach, Annie Le, Brandon Torres Ramirez

Science University Research Symposium (SURS)

The overuse of antibiotics has caused an increase in antibiotic-resistant (AR) bacteria, which is a serious public health concern. Previous studies showed a significant correlation between anthropogenic pollution and AR bacteria. This project aims to identify AR bacteria in Richland Creek relative to local anthropogenic pollution. Water samples were collected at four locations along Richland Creek in Nashville, Tennessee. Bacteria resistant to the antibiotic kanamycin were isolated from the water samples, identified to genera using DNA barcoding, and compared among the sites. We expect to see a greater abundance and diversity of kanamycin-resistant bacteria closer to the end than near …

A Membrane Transporter Required For Quorum Sensing And Virulence Of The Rice Pathogen Burkholderia Glumae, Asif Iqbal

LSU Doctoral Dissertations

Burkholderia glumae is a Gram-negative bacterium causing bacterial panicle blight (BPB) in rice. BPB can cause severe damage to rice and reduce rice yield up to 75%, while no effective treatment has been developed to control the disease. B. glumae produces and secretes an essential virulence factor, toxoflavin, which is mainly responsible for the symptoms of BPB. Synthesis and transport of toxoflavin are regulated in a quorum-sensing dependent manner. Members of the DedA superfamily are putative membrane transporters and found in nearly all species. Mutation of dedA in Burkholderia species results in sensitivity to colistin, an antibiotic belonging to the …

Laguncularia Racemosa Top-Layer Sediment Microorganism Makeup In Relation To Differing Levels Of Perceived Anthropogenic Impact In Bocas Del Drago, Bocas Del Toro, Panama, Gabrielle Glendening

Independent Study Project (ISP) Collection

As mangrove forests are destroyed by human factors across the earth, many crucial ecological processes that take place in these systems of trees are obstructed. One of the most important roles played by mangroves is their ability to sequester carbon in the sediment, as this storage of carbon helps diminish atmospheric warming. Many sediment microorganisms help in this process of carbon sequestration and play various other vital roles in mangrove ecosystems. Microorganisms in marine sediments can be used to assess the health of the surrounding environment. Past research has found significant differences in sediment microorganism composition, abundance, and diversity in …

Forty Years Without Family: Three Novel Bacteriophages With High Similarity To Spp1 Reveal Decades Of Evolutionary Stasis Since The Isolation Of Their Famous Relative, Veronique A. Delesalle, Brianne E. Tomko, Albert C. Vill, Katherine B. Lichty, Gregory P. Krukonis

Biology Faculty Publications

SPP1, an extensively studied bacteriophage of the Gram-positive Bacillus subtilis, is a model system for the study of phage–host interactions. Despite progress in the isolation and characterization of Bacillus phages, no previously fully sequenced phages have shared more than passing genetic similarity to SPP1. Here, we describe three virulent phages very similar to SPP1; SPP1 has greater than 80% nucleotide sequence identity and shares more that 85% of its protein coding genes with these phages. This is remarkable, given more than 40 years between the isolation of SPP1 and these phages. All three phages have somewhat larger genomes and more …

Ridinilazole: A Novel, Narrow-Spectrum Antimicrobial Agent Targeting Clostridium (Clostridioides) Difficile, Deirdre A. Collins, Thomas V. Riley

Research outputs 2022 to 2026

Clostridium (Clostridioides) difficile infection (CDI) remains an urgent threat to patients in health systems worldwide. Recurrent CDI occurs in up to 30% of cases due to sustained dysbiosis of the gut microbiota which normally protects against CDI. Associated costs of initial and recurrent episodes of CDI impose heavy financial burdens on health systems. Vancomycin and metronidazole have been the mainstay of therapy for CDI for many years; however, these agents continue to cause significant disruption to the gut microbiota and thus carry a high risk of recurrence for CDI patients. Treatment regimens are now turning towards novel narrow spectrum antimicrobial …

Genetic Determinants Of Carotenoid Pigmentation In The Opportunistic Pathogen Mycobacterium Kansasii, Niklas Janisch

Dissertations, Theses, and Capstone Projects

Mycobacterium kansasii (Mk) is an opportunistic pulmonary pathogen causing infections, predominantly in immunocompromised people, with symptoms similar to those caused by its close relative Mycobacterium tuberculosis (Mt). In contrast to the latter, little work has been done on Mk genetics and even less on its defining characteristic of photochromogenicity, the controlled expression of carotenoid pigments in response to light exposure.

This work represents major progress in the investigation of pigmentation-related genetic factors in Mk. We report the creation of a large-scale, random transposon-insertion mutant library of Mk and its subsequent screening for mutants with an aberration in the …

Elucidation Of Gene Essentiality And Genetic Determinants Of Intrinsic P-Aminosalicylic Acid Resistance In Mycobacterium Kansasii, Keith J. Levendosky

Dissertations, Theses, and Capstone Projects

Mycobacterium kansasii (Mk) is an opportunistic pathogen capable of causing tuberculosis-like pulmonary disease in immunocompromised individuals and those with other risk factors including chronic obstructive pulmonary disease or malignancy. Mk is frequently isolated from man-made water sources where it forms resilient biofilms, posing a health risk to these susceptible individuals. Despite its medical relevance as an environmental pathogen, and a close phylogenetic relationship with the obligate pathogen Mycobacterium tuberculosis (Mtb), few studies to date have probed the molecular biology and genetics of Mk. Here, we sought to apply a transposon (Tn) mutagenesis tool to dissect …

Esculin Hydrolysis Negative And Tcda-Only Producing Strains Of Clostridium (Clostridioides) Difficile From The Environment In Western Australia, Nirajmohan Shivaperumal, Daniel R. Knight, Korakrit Imwattana, Grace O. Androga, Barbara J. Chang, Thomas V. Riley

Research outputs 2022 to 2026

Background and Aims: Clostridium (Clostridiodes) difficile clade 3 ribotype (RT) 023 strains that fail to produce black colonies on bioMérieux ChromID agar have been reported, as well as variant strains of C. difficile that produce only toxin A. We have recently isolated strains of C. difficile from the environment in Western Australia (WA) with similar characteristics. The objective of this study was to characterize these strains. It was hypothesized that a putative β-glucosidase gene was lacking in these strains of C. difficile, including RT 023, leading to white colonies. Methods and Results: A total of 17 environmental isolates of C. …

Comparative Genomics And Virulence Studies Of Streptomyces Soil Rot And Scab Pathogen Species, Natasha Soares

LSU Doctoral Dissertations

Comparative genomic analyses were performed to gain insights into the organization and content of the genome of Streptomyces ipomoeae, the soil rot pathogen that infects sweetpotatoes. Unlike Streptomyces scab pathogens, the thaxtomin phytotoxin gene cluster (txt) in S. ipomoeae does not appear to reside within a genomic island and has diverged from its scab pathogen counterparts. Increased usage of the rare TTA codon, particularly for the txt cluster, suggests greater translational control by the bldA tRNA in S. ipomoeae. Orthologous gene searches and secondary metabolite profiling yielded ortholog groups and metabolite gene clusters that were exclusive …

Novel Signal Sequences And Fusion Partners For Paratransgenesis In Asaia, Christina Grogan

Electronic Theses and Dissertations

Mosquitoes transmit many pathogens that cause human disease. One such disease, malaria, is caused by parasites in the genus Plasmodium, infecting over 200 million people and killing over 600,000 per year. Current strategies to control vector-transmitted diseases are increasingly undermined by mosquito and pathogen resistance. Research has turned to additional and novel methods of control, such as altering the microbiota of the vectors. In this method, called paratransgenesis, symbiotic bacteria are genetically modified to affect the mosquito’s phenotype by engineering them to deliver antiplasmodial molecules into the midgut to kill parasites. These molecules must be released by the …

Perception Of Illness And Its Association With Willingness To Adhere To Treatment In Chronic Hepatitis C Patients With New Diagnosis Of Nonalcoholic Fatty Liver Disease, Carmel Kruse

The Eleanor Mann School of Nursing DNP Capstone Projects

Chronic liver disease is becoming the most common cause of mortality, morbidity, and utilization of healthcare services globally. Both nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis C (CHC) are frequent causes of chronic liver disease. Recently, there have been significant findings on the relationship between NAFLD and CHC; patients with CHC have a higher incidence of NAFLD. The introduction of direct-acting antivirals has cured more CHC patients than ever before. Unfortunately, the current interventions for NAFLD requiring behavioral change remain ineffective. Patient’s ability to follow advice depends largely on their health beliefs; therefore, understanding their illness perception is an …

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 …

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, …

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 …

Reproductive Ecology And Microbial Communities From Wood Duck Nest Boxes In Georgia And Florida, Jake Shurba

All Theses

Wood ducks (Aix sponsa) are an important game species throughout the Atlantic Flyway that was nearly extirpated by the early 20^th century due to overhunting and the loss of habitat. Wood ducks are secondary cavity-nesters that utilize artificial nest boxes and natural cavities. It is reported that the use of nest boxes is likely what led to re-establishment of the species in North America. Where boxes are numerous, overuse of boxes by multiple hens throughout a nesting season can occur and result in a buildup of bacteria, parasites and other potentially detrimental pathogens that can impact egg …

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 …

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). …