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Deacylated Trna Accumulation Is A Trigger For Bacterial Antibiotic Persistence Independent Of The Stringent Response, Whitney N. Wood, Kyle Mohler, Jesse Rinehart, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacterial antibiotic persistence occurs when bacteria are treated with an antibiotic and the majority of the population rapidly dies off, but a small subpopulation enters into a dormant, persistent state and evades death. Diverse pathways leading to nucleoside triphosphate (NTP) depletion and restricted translation have been implicated in persistence, suggesting alternative redundant routes may exist to initiate persister formation. To investigate the molecular mechanism of one such pathway, functional variants of an essential component of translation (phenylalanyltRNA synthetase [PheRS]) were used to study the effects of quality control on antibiotic persistence. Upon amino acid limitation, elevated PheRS quality control led …

Prophylactic Phage Therapy In Infant Rabbits Model Of Cholera, Sadeq Ag Kaabi Asst Prof Dr

Karbala International Journal of Modern Science

A number of 8 phages lytic of V. cholerae O1- biotype-EI-Tor, serotype Inaba were selected for the formulation of a phage cocktail. A phage cocktail composed of 8 phages was prepared and showed 100% inhibition of V. cholerae isolates comparing with a percentage ranged from 0-75% for every single phage in growth inhibition assay. The potential activity of phage cocktail of prophylactic therapy for infant rabbits model of cholera was evaluated through phage retention time and length of phage prophylaxis studies. Results have been showed that phage cocktail was potent in the prevention of development of cholera in infant rabbits …

Prevalence And Risk Factors Associated With Multi-Drug Resistant Organisms (Mdro) Carriage Among Pediatric Patients At The Time Of Admission In A Tertiary Care Hospital Of A Developing Country. A Cross-Sectional Study, Sonia Qureshi, Noshi Maria, Mohammad Zeeshan, Seema Irfan, Farah Naz Qamar

Department of Paediatrics and Child Health

Background: The rise of Multidrug-resistant organisms (MDROs) poses a considerable burden on the healthcare systems, particularly in low-middle income countries like Pakistan. There is a scarcity of data on the carriage of MDRO particularly in the pediatrics population therefore, we aimed to determine MDRO carriage in pediatric patients at the time of admission to a tertiary care hospital in Karachi, Pakistan, and to identify the risk factors associated with it.
Methods: A cross-sectional study conducted at the pediatric department of Aga Khan University Hospital (AKUH) from May to September 2019 on 347 children aged 1-18 years. For identification of MDRO …

Development And Validation Of An Isothermal Amplification Assay For Eastern Equine Encephalitis Virus, Mikayla D. Maddison

USF Tampa Graduate Theses and Dissertations

Eastern Equine Encephalitis virus (EEEV) is a neurotrophic alphavirus for which there is no effective treatment or vaccine for humans. Periodic outbreaks in the Eastern United States represent an ongoing public health problem; Florida serves as the reservoir for EEEV for the rest of the country. Reverse transcription-polymerase chain reaction (RT-PCR) is the current gold standard for molecular diagnostic testing of the presence of EEEV in vectors. However, RT-PCR is technically complex and can be difficult for mosquito control districts to utilize. In order to provide a simple, cost-effective alternative for mosquito surveillance and control, a novel one step reverse …

Draft Genome Sequences Of 13 Vibrio Cholerae Strains From The Rio Grande Delta, Jeffrey W. Turner, Jorge Duran-Gonzalez, David A. Laughlin, Daniel Unterweger, David Silva, Boris Ermolinsky, Stefan Pukatzki, Daniele Provenzano

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Vibrio cholerae is the etiologic agent of cholera, an acute and often fatal diarrheal disease that affects millions globally. We report the draft genome sequences of 13 non-O1/O139 V. cholerae strains isolated from the Rio Grande Delta in Texas. These genomes will aid future analyses of environmental serovars.

Draft Genome Sequences Of 13 Vibrio Cholerae Strains From The Rio Grande Delta, Jeffrey W. Turner, Jorge Duran-Gonzalez, David A. Laughlin, Daniel Unterweger, David Silva, Boris Ermolinsky, Stefan Pukatzki, Daniele Provenzano

Publications and Research

Vibrio cholerae is the etiologic agent of cholera, an acute and often fatal diarrheal disease that affects millions globally. We report the draft genome sequences of 13 non-O1/O139 V. cholerae strains isolated from the Rio Grande Delta in Texas. These genomes will aid future analyses of environmental serovars.

Psychological Impact Of Novel Coronavirus Covid-19 Across The Globe-A Review, Sadaf Shaheen, Iram Asim, Rida Zainab, Humaira Yasmeen

Journal of Bioresource Management

The recent outbreaks of novel coronavirus disease have unprecedent impact on mental health of patients, front-line healthcare workers and local population. However, the impact is not fully documented. This review explores stress-driven factors, stress-vulnerable groups and stress management interventions. Repetitive exposure to mass media and inappropriate health protective measures has heightened stress responses. Fear of not getting recovered from COVID-19 and disaffection has profound impact of infected individuals and their families. They may experience fear, anxiety, anger, sleep deprives and anorexia which may weakens their immune system thus making them vulnerable to COVID-19. The COVID-19 pandemic has underscored potential gaps …

Mucormycosis (Black Fungus) Maiming Covid Patients: Scientometrics Analysis Through Prism Of Biblioshiny, Sivankalai S, K Sivasekaran

Library Philosophy and Practice (e-journal)

This study analyses the global level outlook of research publications on Mucormycosis output between the period of 1923 to 2021 (May) on different limitations including contribution of authors, communication channel, publications on Institutions, countries, Journals, cited articles and mode of languages. 4451 data was downloaded from core collection of Web of Science bibliographic database using the search term ‘Mucormycosis’ and limited the publications 1900 to 2021, first publication was started in 1923 onwards. 3798 institutions and 8562 different disciplines contributed and 2808 records are in Articles. 4451 records published by 17320 authors and 23552 collaborated authors, documents per author are …

Increased Antimicrobial And Multidrug Resistance Downstream Of Wastewater Treatment Plants In An Urban Watershed, Maitreyee Mukherjee, Edward Laird, Terry J. Gentry, John P. Brooks, Raghupathy Karthikeyan

Faculty Publications

Development and spread of antimicrobial resistance (AMR) and multidrug resistance (MDR) through propagation of antibiotic resistance genes (ARG) in various environments is a global emerging public health concern. The role of wastewater treatment plants (WWTPs) as hot spots for the dissemination of AMR and MDR has been widely pointed out by the scientific community. In this study, we collected surface water samples from sites upstream and downstream of two WWTP discharge points in an urban watershed in the Bryan-College Station (BCS), Texas area, over a period of nine months. E. coli isolates were tested for resistance to ampicillin, tetracycline, sulfamethoxazole, …

Design, Synthesis, And Evaluation Of Carbapenem And Cephalosporin Antibiotics To Counter Resistant 21st Century Pathogens, Maha Alqurafi

Chemistry Theses and Dissertations

Antibiotics represent one of mankind’s most important discoveries, enabling longer, more productive lives. Carbapenem antibiotics are one of the most potent classes of β-lactams and often represent the last resort used to treat patients who are seriously stricken by bacterial infections. Carbapenems possess a broad spectrum of antibacterial activity including efficacy against the majority of Gram-positive and Gram–negative bacteria. Unfortunately, the emergence of antibiotic resistant strains is posing a serious threat to existing antibiotics. New discoveries in the antibiotic field are desperately needed to counter the threat of rapidly evolving bacterial resistance. Despite the investment of billions of dollars, and …

Genome Sequence Of A Virulent African Swine Fever Virus Isolated In 2020 From A Domestic Pig In Northern Vietnam, Quang Lam Truong, Thi Lan Nguyen, Thi Hoa Nguyen, Jishu Shi, Hiep Lai Xuan Vu, Thi Lan Huong Lai, Van Giap Nguyen

Nebraska Center for Virology: Faculty Publications

This study reports the genome sequence of an isolated African swine fever (ASF) virus (VNUA-ASFV-05L1/HaNam) obtained at the fourth passage on pulmonary alveolar macrophages. The virus was isolated during a typical acute ASF outbreak in pigs in a northern province of Vietnam in 2020.

Codon Bias Can Determine Sorting Of A Potassium Channel Protein, Anja J. Engel, Marina Kithil, Markus Langhans, Oliver Rauh, Matea Cartolano, James L. Van Etten, Anna Moroni, Gerhard Thiel

Nebraska Center for Virology: Faculty Publications

Due to the redundancy of the genetic code most amino acids are encoded by multiple synonymous codons. It has been proposed that a biased frequency of synonymous codons can affect the function of proteins by modulating distinct steps in transcription, translation and folding. Here, we use two similar prototype K⁺ channels as model systems to examine whether codon choice has an impact on protein sorting. By monitoring transient expression of GFP-tagged channels in mammalian cells, we find that one of the two channels is sorted in a codon and cell cycle-dependent manner either to mitochondria or the secretory pathway. …

Molecular Detection Of Pathogenic Leptospira And Microbial Source Tracking Of Fecal Pollution In San Juan, Puerto Rico, Taylor I. Chapman

Biology Theses

Leptospirosis, caused by pathogenic Leptospira, is endemic to tropical regions. Leptospira is released into the environment through the secretion of urine from animals, making it easily transmissible through water sources. The estuarian environment surrounding the area of San Juan, Puerto Rico and its high density of urban development creates ideal conditions for transmission of Leptospirosis. The goal of this study was to determine the presence of Leptospira in these surface waters and use Microbial Source Tracking (MST) to identify the possible source of pathogenic Leptospira. Eighty-seven water samples were collected during the dry (44) and wet (43) seasons. …

Sickness Behaviors Across Vertebrate Taxa: Proximate And Ultimate Mechanisms, Patricia C. Lopes, Susannah S. French, Douglas C. Woodhams, Sandra A. Binning

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

There is nothing like a pandemic to get the world thinking about how infectious diseases affect individual behavior. In this respect, sick animals can behave in ways that are dramatically different from healthy animals: altered social interactions and changes to patterns of eating and drinking are all hallmarks of sickness. As a result, behavioral changes associated with inflammatory responses (i.e. sickness behaviors) have important implications for disease spread by affecting contacts with others and with common resources, including water and/or sleeping sites. In this Review, we summarize the behavioral modifications, including changes to thermoregulatory behaviors, known to occur in vertebrates …

Sodium Pyruvate Ameliorates Influenza A Virus Infection In Vitro And In Vivo, Jessica M. Reel

Graduate Theses/Dissertations

Pyruvate is produced in duplicate at the end of glycolysis in addition to ATP and NADH. Pyruvate is the metabolite of choice in most cells, whether obtained exogenously or endogenously. Recently we found that the addition of pyruvate’s conjugate base, sodium pyruvate, to cell culture media dampened the immune response to influenza A virus (IAV) infection in cultured innate immune cells. Thus, I decided to investigate the mechanism and potential for treatment of IAV. In vitro using bone marrow derived macrophages that were infected with IAV we found that adding sodium pyruvate to the media decreased immune signaling pathways through …

Elevated Incidences Of Antimicrobial Resistance And Multidrug Resistance In The Maumee River (Ohio, Usa), A Major Tributary Of Lake Erie, Maitreyee Mukherjee, Leah Marie, Cheyenne Liles, Nadia Mustafa, George Bullerjahn, Terry J. Gentry, John P. Brooks

Faculty Publications

Maumee River, the major tributary in the western basin of Lake Erie, serves as one of major sources of freshwater in the area, supplying potable, recreational, and industrial water. In this study we collected water samples from four sites in the Maumee River Bay between 2016–2017 and E. coli was isolated, enumerated, and analyzed for antimicrobial resistance (AMR) and multidrug resistance (MDR). Strikingly, 95% of the total isolates were found to be resistant to at least one antibiotic. A very high resistance to the drugs cephalothin (95.3%), ampicillin (38.3%), tetracycline (8.8%), gentamicin (8.2%), ciprofloxacin (4.2%), cefoperazone (4%), and sulfamethoxazole (1.5%) …

The Role Of Gac/Rsm Signal Transduction Pathway In The Biology Of Antagonistic Marine Bacterium Gynuella Sunshinyii 449, Anhthu Truong

Honors Theses

Gynuella sunshinyii is a newly characterized bacterium with a remarkable ability to produce multiple secondary metabolites that act as potential antibiotics for medical applications. Currently, little is known about gene regulation in this unusual microorganism. In 2018, studies conducted of rhizosphere microbiomes of tidal marsh grasses on Deer Island, MS, resulted in multiple isolates of halophilic, aerobic, Gram-negative bacteria with antagonistic properties. One of the most active antagonists was identified as Gynuella sunshinyii 449. The genome of strain 449 was sequenced with Illumina MiSeq, assembled with Unicycler and SPAdes, and annotated with RASTtk. The annotation revealed a 6.09 Mb genome …

The Impact Of Oxygen Availability And Oxidative Stress On Regulation Of Cyclic-Dimeric-Gmp In Listeria Monocytogenes Strain F2365, Anna G. Welch

Honors Theses

Listeria monocytogenes is a gram-positive foodborne pathogen that results in the infectious disease listeriosis. The second messenger molecule cyclic-dimeric-GMP has been found to be responsible for the regulation of expression of many of its virulence factors with diguanylate cyclases and phosphodiesterases regulating the intracellular concentration of cyclic-di-GMP through synthesis and degradation, respectively. This study investigated the possibility that the availability of oxygen is the environmental signal crucial to the regulation of these enzymes. Prior research in our laboratory has demonstrated that the intracellular concentration of cyclic-di-GMP is elevated when exposed to anaerobic conditions. Due to this, it was hypothesized that …

Study Of The Role Of The Msaabcr Operon In Tricarboxylic Acid Cycle Activity And Persister Cell Formation In Staphylococcus Aureus, Karsen Motter

Honors Theses

Staphylococcus aureus is an important human pathogen that causes wide arrays of infections ranging from minor skin infections to lethal systemic conditions such as infective endocarditis, osteomyelitis, sepsis and pneumonia. These systemic diseases are often difficult to treat due to the presence of persister cells. Persister cells are a phenotypic variant of the bacterial population that exhibit extreme and transient antibiotic tolerance accompanied by a transient halt in growth. Upon cessation of antibiotic treatment, however, persisters resume growth which results in recurrence of infections. This characteristic of persister cells therefore displays high clinical significance. In this study, we show the …

Implications Of The Evolutionary Past On The Activities Of Virb: A Key Transcriptional Regulator Of Virulence Genes In Shigella Flexneri, Jillian Nicole Socea

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shigella species are bacterial agents that are the leading cause of diarrheal diseases, the second leading cause of child mortality worldwide. One key protein in Shigella is VirB, a transcriptional regulator of virulence genes that is essential for pathogenicity. VirB functions to antagonize H-NS, a histone-like nucleoid structuring protein that silences many genes found on the large virulence plasmid (pINV). The interplay between H-NS, the silencer, and VirB, the anti-silencer, is fundamental for Shigella virulence. Furthermore, this mechanism of gene regulation appears widespread in many bacteria including other enteric pathogens.

The goal of my dissertation was to explore the activities …

Unraveling Host-Gut Microbiota Dialogue And Its Impact On Response To Immune Checkpoint Blockade, Alexandria Cogdill

Dissertations and Theses (Open Access)

Cancer is a disease with only one degree of separation, affecting one in two men and one in three women in their lifetimes; accounting for 1 of every 6 deaths. While cancer mortality rates continue to improve, incidence rates are expected to rise and shift through 2050 due to epidemiological and demographic transitions worldwide. As such, it is imperative to continue to investigate and improve our understanding of both disease etiology and hallmarks of response to treatment. Currently, conventional therapies include, but are not limited to, surgery, chemotherapy, and radiotherapy. However, within the past decade, major advances have been made …

Suppression Of Inflammation Of Cytokine Following Induced Francisella Tularensis Infection, Nicole Renee Setzu

Open Access Theses & Dissertations

Francisella tularensis is intracellular bacteria which is the causative agent of the disease Tularemia. Highly virulent in both humans and animals, it takes only as few as 10 microorganisms to cause a lethal infection. The bacteria can enter via direct or indirect routes causing the activations of the host innate inflammatory response to ensue. The bacteria invade host dendritic cells and neutrophils but predominately macrophages. This causes a mass inflammatory response resulting in the cytokine storm. Activation of Natural Killer T (NKT) cells has been shown to suppress inflammation in in vivo studies. Development and optimization of an in vitro …

Developing A Microdialysis Sampling-Based Biofilm/Macrophage Co-Culture Model, Alda Diaz Perez

Graduate Theses and Dissertations

The host immune system and bacterial cells are known to interact during the human lifetime. Bacteria secrete a wide variety of signaling molecules, known as quorum sensing (QSC) molecules, that modulate the host immune system. While immune-biofilm interactions involve this chemical signaling network, the mechanisms through which this occurs are not well understood. This work aimed to develop a new method that can be used not only in vitro settings but also in vivo. The microdialysis sampling technique has widely been used in in vitro and in vivo settings in humans, mice, and rats for the collection of neuropeptides, cytokines, …

Identification Of A Chlorovirus Pbcv-1 Protein Involved In Degrading The Host Cell Wall During Virus Infection, Irina V. Agarkova, Leslie C. Lane, David D. Dunigan, Cristian F. Quispe, Garry A. Duncan, Elad Milrot, Abraham Minsky, Ahmed Esmael, Jayadri S. Ghosh, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

Chloroviruses are unusual among viruses infecting eukaryotic organisms in that they must, like bacteriophages, penetrate a rigid cell wall to initiate infection. Chlorovirus PBCV-1 infects its host, Chlorella variabilis NC64A by specifically binding to and degrading the cell wall of the host at the point of contact by a virus-packaged enzyme(s). However, PBCV-1 does not use any of the five previously characterized virus-encoded polysaccharide degrading enzymes to digest the Chlorella host cell wall during virus entry because none of the enzymes are packaged in the virion. A search for another PBCV-1-encoded and virion-associated protein identified protein A561L. The fourth domain …

The Anti-Sigma Factor Muca Is Required For Viability In Pseudomonas Aeruginosa, Melissa C. Schofield, Daniela Q. Rodriguez, Amanda A. Kidman, Erin K. Cassin, Lia A. Michaels, Elizabeth A. Campbell, Peter A. Jorth, Boo Shan Tseng

Teaching and Learning Faculty Research

During decades-long infections in the cystic fibrosis (CF) airway, Pseudomonas aeruginosa undergoes selection. One bacterial genetic adaptation often observed in CF isolates is mucA mutations. MucA inhibits the sigma factor AlgU. Mutations in mucA lead to AlgU misregulation, resulting in a mucoid phenotype that is associated with poor CF disease outcomes. Due to its ability to be mutated, mucA is assumed to be dispensable for bacterial viability. Here we show that, paradoxically, a portion of mucA is essential in P. aeruginosa. We demonstrate that mucA is no longer required in a strain lacking algU, that mucA alleles encoding for proteins …

Increasing The Frequency Of Periodic Spatial Disturbance Decreases Surface Attachment Protein Expression In Staphylococcus Aureus, Ivana M. Barraza

All HCAS Student Capstones, Theses, and Dissertations

Staphylococcus aureus is an opportunistic pathogen that can cause a variety of acute and chronic illnesses. The severity of these illnesses such as sepsis, necrotizing pneumonia, and toxic shock syndrome is measured through the virulence that S. aureus inflicts on its host. Methicillin-resistant S. aureus (MRSA) is commonly associated with secondary infections and is challenging to treat given the limited selection of antibiotics that are effective against it. Accordingly, novel approaches to reduce S. aureus pathogenicity are required. S. aureus regulates pathogenesis through a cell-to-cell communication system referred to as quorum sensing. Effective communication determines the production of two broad …

Respiratory Pathogens In Patients With Acute Exacerbation Of Non-Cystic Fibrosis Bronchiectasis From A Developing Country, Shayan Shahid, Kausar Jabeen, Nousheen Iqbal, Joveria Farooqi, Muhammad Irfan

Medical College Documents

Bronchiectasis unrelated to cystic fibrosis (non-CF bronchiectasis) has become a major respiratory disease in developing nations. The dilated mucus filled airways promote bacterial overgrowth followed by chronic infection, bronchial inflammation, lung injury and re-infection Accurate pathogen identification and antimicrobial susceptibility allowing appropriate treatment, in turn, may break this vicious cycle. To study the spectrum and antimicrobial spectrum of pathogen yielded from respiratory specimens in adult patients with acute exacerbation of non-cystic fibrosis (CF) bronchiectasis. This cross-sectional study was performed at the pulmonology clinics of the Aga Khan University, Karachi, Pakistan from 2016-2019. Respiratory specimens were collected from adult patients with …

The Msaabcr Operon Regulates Persister Formation By Modulating Energy Metabolism In Staphylococcus Aureus, Shanti Pandey, Gyan S. Sahukhal, Mohamed O. Elasri

Faculty Publications

Staphylococcus aureus is a major human pathogen that causes chronic, systemic infections, and the recalcitrance of these infections is mainly due to the presence of persister cells, which are a bacterial subpopulation that exhibits extreme, yet transient, antibiotic tolerance accompanied by a transient halt in growth. However, upon cessation of antibiotic treatment, a resumption in growth of persister cells causes recurrence of infections and treatment failure. Previously, we reported the involvement of msaABCR in several important staphylococcal phenotypes, including the formation of persister cells. Additionally, observations of the regulation of several metabolic genes by the msaABCR operon in transcriptomics and …

B25: Generation And Characterization Of Sars-Cov-2 Spike Protein-Pseudotyped Lentivirus Particles For Use In Neutralizing Antibody Titer Testing Of Human Serum, Luis Sanchez

Annual Research Symposium

No abstract provided.

B16: Chikungunya Virus Time Course Infection Of Human Macrophages, Madison Gray, Israel Guerrero-Arguero, Antonio Solis Leal, Richard Robison, Brad Burges, Brett Pickett

Annual Research Symposium

Chikungunya virus (CHIKV) is an Alphavirus spread by Aedes spp. mosquitoes and is responsible for infecting 1.1 million people per year worldwide, including a large epidemic in the western hemisphere in 2014-2015. During the body’s immune response to CHIKV, human macrophages become infected after phagocytosis of CHIKV and undergo induced apoptosis, catalyzing the virus spread in the body. It is presently unclear what macrophage genes, functions, and intracellular signaling pathways are impacted during the early, intermediate, and late stages of CHIKV infection. Therefore we quantified the transcriptional response of human macrophage cells infected with CHIKV at two different timepoints.