Microbiology Commons^™

A Rulebook For Peptide Control Of Legume–Microbe Endosymbioses, Sonali Roy, Lena Maria Müller

Agricultural and Environmental Sciences Faculty Research

Plants engage in mutually beneficial relationships with microbes, such as arbuscular mycorrhizal fungi or nitrogen-fixing rhizobia, for optimized nutrient acquisition. In return, the microbial symbionts receive photosynthetic carbon from the plant. Both symbioses are regulated by the plant nutrient status, indicating the existence of signaling pathways that allow the host to fine-tune its interactions with the beneficial microbes depending on its nutrient requirements. Peptide hormones coordinate a plethora of developmental and physiological processes and, recently, various peptide families have gained special attention as systemic and local regulators of plant–microbe interactions and nutrient homeostasis. In this review, we identify five 'rules' …

Genes Critical For Flagellar Motility In Agrobacterium Fabrum, Audrey Memmott, Joel Griffitts

Library/Life Sciences Undergraduate Poster Competition 2022

The flagellum contains 24 structural proteins that are vital for bacterial motility and virulence (Liu). Additionally, these structural proteins must be assembled in the correct order and orientation for a bacterium to be motile via its flagellum (Armitage). Our current knowledge regarding the flagellum is limited, however, because the majority of it comes from studies focused on Escherichia coli. To increase existing knowledge regarding the flagellum and the genes vital for its functionality, we attempted to define all the genes vital for flagellar motility in A. fabrum by analyzing motility when specific genes are disrupted.

Overcoming Detrimental Potato Fungi In Potato Fields With The Secondary Metabolites Of Naturally Occurring Steptomyces, Hansan Jones, Jacob Anderson, Erik Kemp, Brad Geary, Matthew Madsen, Ryan Stewart

Library/Life Sciences Undergraduate Poster Competition 2022

• Fungal disease Silver scurf can cause 13% water loss and give poor aesthetic appeal, both of which reduce farmers profits (1,2).
• Pythium leak can result in up to 50% total loss of potatoes in storage (3)
• Streptomyces is the right candidate to mitigate or eliminate these losses because of its ability to survive in soil (4) and its history as a proven biocontrol for other plant pathogens (5).

The Role Of Cd5 In Cd4+ T Cell Metabolism, Joshua Bennett, Kiara Whitley, Claudia Freitas Phd, Christopher Haynie, Carlos Moreno, Scott Weber

Library/Life Sciences Undergraduate Poster Competition 2022

T cells serve a key role in the immunological response in the adaptive system. Different receptors present on the T cell have certain roles and are able to either inhibit or stimulate signaling which consequently regulates the function and metabolism of the cell. CD5 is an inhibitory co receptor expressed on the surface of T cells known to regulate thymocyte selection and TCR signaling . Our goal is to better understand the effects of CD5 regulation in metabolism. Using metabolic flux assays, we found that CD5KO naïve T cells have increased glycolysis and mitochondrial respiration in comparison to wild type …

Potential Regulation Of Breast Cancer Invasion By Thymidine Kinase 1, Eliza E. Bitter, Rachel M. Morris, Toni O. Mortimer, Kai Barlow, Abigail Schekall, Michelle H. Townsend, Jonathan Skidmore, Brett E. Pickett, Kim L. O'Neill

Library/Life Sciences Undergraduate Poster Competition 2022

Breast cancer is the most common cancer in women and is largely treatable within the early stages of the disease. However, patient mortality drastically declines as the tumor begins to invade other tissues and metastasize, making aggressive phenotypes especially problematic to treat. Such treatment typically requires an aggressive and decisive multidisciplinary approach. The recent expansion of immunotherapy as a viable treatment option has greatly improved treatment outcomes, especially with aggressive breast cancer phenotypes. Thymidine kinase 1 (TK1) is a DNA salvage pathway enzyme that is highly expressed during S phase and involved in cell cycle repair. Past studies indicated that …

Development Of A Methodology For The Quantification Of Reaerosolization Of A Biological Contaminant Surrogate Particle From Military Uniform Fabric, George D. Cooksey

Theses and Dissertations

During a mass casualty medical evacuation after a bioaerosol attack, a decontamination method is needed that is effective at both decontamination and preventing the secondary hazard of biological particles reaerosolizing from contaminated clothing. However, neither the efficacy of current decontamination methods nor the risk of biological particle reaerosolization is significantly explored in existing literature. The goals of this thesis were to develop a repeatable methodology to quantify the reaerosolization of a biological contaminate off Airman Battle Uniform (ABU) fabric swatches, and to test the efficacy of one decontamination method (high-volume, low-pressure water) using 1 mpolystyrene latex (PSL) spheres as a …

An Insight Into The Microrna Profile Of The Ectoparasitic Mite Varroa Destructor (Acari: Varroidae), The Primary Vector Of Honey Bee Deformed Wing Virus, Deepak Kumar, Mohamed Alburaki, Faizan Tahir, Michael Goblirsch, John Adamczyk, Shahid Karim

Faculty Publications

The remarkably adaptive mite Varroa destructor is the most important honey bee ectoparasite. Varroa mites are competent vectors of deformed wing virus (DWV), and the Varroa-virus complex is a major determinant of annual honey bee colony mortality and collapse. MicroRNAs (miRNAs) are 22-24 nucleotide non-coding RNAs produced by all plants and animals and some viruses that influence biological processes through post-transcriptional regulation of gene expression. Knowledge of miRNAs and their function in mite biology remains limited. Here we constructed small RNA libraries from male and female V. destructor using Illumina’s small RNA-Seq platform. A total of 101,913,208 and 91,904,732 …

Identifying Causative Microorganisms In Left Ventricular Assist Device Infections As A Guide For Developing Bacteriophage Therapy, Ishan Kamat, Harveen Lamba, Casey Hines-Munson, Samuel Hudson, Kenneth Liao, Kenneth L Muldrew, Sabrina Green, Austen Terwilliger, Heidi B Kaplan, Robert F Ramig, Anthony Maresso, Barbara W Trautner

Faculty, Staff and Students Publications

BACKGROUND: As more left ventricular-assist devices (LVADs) are implanted, multidrug-resistant LVAD infections are becoming increasingly common, partly due to bacterial biofilm production. To aid in developing bacteriophage therapy for LVAD infections, we have identified the most common bacterial pathogens that cause LVAD driveline infections (DLIs) in our heart transplant referral center.

MATERIALS AND METHODS: We studied a retrospective cohort of patients who received LVADs from November 2003 to August 2017 to identify the common causative organisms of LVAD infection. We also studied a prospective cohort of patients diagnosed with DLIs from October 2018 to May 2019 to collect bacterial strains …

Epigallocatechin-3-Gallate (Egcg): New Therapeutic Perspectives For Neuroprotection, Aging, And Neuroinflammation For The Modern Age, Ashley Payne, Samuel N. Nahashon, Equar Taka, Getinet M. Adinew, Karam F. A. Soliman

Agricultural and Environmental Sciences Faculty Research

Alzheimer's and Parkinson’s diseases are the two most common forms of neurodegenerative diseases. The exact etiology of these disorders is not well known; however, environmental, molecular, and genetic influences play a major role in the pathogenesis of these diseases. Using Alzheimer’s disease (AD) as the archetype, the pathological findings include the aggregation of Amyloid Beta (Aβ) peptides, mitochondrial dysfunction, synaptic degradation caused by inflammation, elevated reactive oxygen species (ROS), and cerebrovascular dysregulation. This review highlights the neuroinflammatory and neuroprotective role of epigallocatechin-3-gallate (EGCG): the medicinal component of green tea, a known nutraceutical that has shown promise in modulating AD progression …

Carbapenemase-Producing Pseudomonas Aeruginosa – An Emerging Challenge, Fred C. Tenover, David P. Nicolau, Christian M. Gill

Biology Faculty Publications

Carbapenem-resistant Pseudomonas aeruginosa (CR-PA) is a major healthcare-associated pathogen worldwide. In the United States, 10–30% of P. aeruginosa isolates are carbapenem-resistant, while globally the percentage varies considerably. A subset of carbapenem-resistant P. aeruginosa isolates harbour carbapenemases, although due in part to limited screening for these enzymes in clinical laboratories, the actual percentage is unknown. Carbapenemase-mediated carbapenem resistance in P. aeruginosa is a significant concern as it greatly limits the choice of anti-infective strategies, although detecting carbapenemase-producing P. aeruginosa in the clinical laboratory can be challenging. Such organisms also have been associated with nosocomial spread requiring infection prevention interventions. The carbapenemases …

Recent Advances In Probiotic Application In Animal Health And Nutrition: A Review, Sarayu Bhogoju, Samuel Nahashon

Agricultural and Environmental Sciences Faculty Research

Biotechnological advances in animal health and nutrition continue to play a significant role in the improvement of animal health, growth, and production performance. These biotechnological advancements, especially the use of direct-fed microbials, also termed probiotics, those genetically modified and otherwise, have minimized many challenges facing livestock production around the world. Such advancements result in healthy animals and animal products, such as meat, for a growing population worldwide. Increasing demand for productivity, healthy animals, and consumer food safety concerns, especially those emanating from excessive use of antibiotics or growth promoters, are a driving force for investing in safer alternatives, such as …

Escherichia Coli Alanyl-Trna Synthetase Maintains Proofreading Activity And Translational Accuracy Under Oxidative Stress, Arundhati Kavoor, Paul Kelly, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) are enzymes that synthesize aminoacyl-tRNAs to facilitate translation of the genetic code. Quality control by aaRS proofreading and other mechanisms maintains translational accuracy, which promotes cellular viability. Systematic disruption of proofreading, as recently demonstrated for alanyl-tRNA synthetase (AlaRS), leads to dysregulation of the proteome and reduced viability. Recent studies showed that environmental challenges such as exposure to reactive oxygen species can also alter aaRS synthetic and proofreading functions, prompting us to investigate if oxidation might positively or negatively affect AlaRS activity. We found that while oxidation leads to modification of several residues in Escherichia coli AlaRS, unlike …

Fully Resolved Assembly Of Cryptosporidium Parvum, Vipin K Menon, Pablo C Okhuysen, Cynthia L Chappell, Medhat Mahmoud, Medhat Mahmoud, Qingchang Meng, Harsha Doddapaneni, Vanesa Vee, Yi Han, Sejal Salvi, Sravya Bhamidipati, Kavya Kottapalli, George Weissenberger, Hua Shen, Matthew C Ross, Kristi L Hoffman, Sara Javornik Cregeen, Donna M Muzny, Ginger A Metcalf, Richard A Gibbs, Joseph F Petrosino, Fritz J Sedlazeck

Faculty, Staff and Students Publications

BACKGROUND: Cryptosporidium parvum is an apicomplexan parasite commonly found across many host species with a global infection prevalence in human populations of 7.6%. Understanding its diversity and genomic makeup can help in fighting established infections and prohibiting further transmission. The basis of every genomic study is a high-quality reference genome that has continuity and completeness, thus enabling comprehensive comparative studies.

FINDINGS: Here, we provide a highly accurate and complete reference genome of Cryptosporidium parvum. The assembly is based on Oxford Nanopore reads and was improved using Illumina reads for error correction. We also outline how to evaluate and choose from …

Your Next Celebration At Us National Parks: A Case Emphasizing Lyme Neuroborreliosis (Bannwarth Syndrome), Ganesh Arun, Farhan Ali, Sowmya Srinivas, Harsha Surath, Justin Nistico, Dayakar Reddy

Advances in Clinical Medical Research and Healthcare Delivery

Introduction:

Bannwarth syndrome is synonymous with Lyme neuroborreliosis. The neurological component consists of neuropathy, radicular pain, and lymphocytic pleocytosis. This is due to inflammation of the nerve fibers by Borrelia Burgdorferi. Borrelia Borgdorferi is a spirochete bacteria transmitted hematogenously from the Ixodes tick vector to the human host. The commonly known Lyme disease is diagnosed with symptoms of arthritis, heart block, and integumentary signs. Lyme disease can present as early disseminated or late manifestations of disease. Bannwarth syndrome takes it a step further and emphasizes the neurologic sub set of symptoms. The Centers for Disease Control and Prevention (CDC) estimates …

Reducing Influenza Virus Transmission: The Potential Value Of Antiviral Treatment, Frederick G Hayden, Jason Asher, Benjamin J Cowling, Aeron C Hurt, Hideyuki Ikematsu, Klaus Kuhlbusch, Annabelle Lemenuel-Diot, Zhanwei Du, Lauren Ancel Meyers, Pedro A Piedra, Takahiro Takazono, Hui-Ling Yen, Arnold S Monto

Faculty, Staff and Students Publications

Prompt antiviral treatment has the potential to reduce influenza virus transmission to close contacts, but rigorous data on the magnitude of treatment effects on transmission are limited. Animal model data indicate that rapid reductions in viral replication after antiviral treatment reduce the risk of transmission. Observational and clinical trial data with oseltamivir and other neuraminidase inhibitors indicate that prompt treatment of household index patients seems to reduce the risk of illness in contacts, although the magnitude of the reported effects has varied widely across studies. In addition, the potential risk of transmitting drug-resistant variants exists with all approved classes of …

Detection Of Methicillin-Resistant Staphylococcus Aureus Infections Using Molecular Methods, Fred C. Tenover, Isabella A. Tickler

Biology Faculty Publications

The application of molecular detection methods for bacterial pathogens has dramatically improved the outcomes of septic patients, including those with methicillin-resistant Staphylococcus aureus (MRSA) infections. Molecular methods can be applied to a variety of clinical specimens including nasal swabs, growth in blood culture bottles, and wounds. While data show that the overall accuracy of molecular tests for MRSA is high, results can be confounded by the presence of multiple staphylococcal species in a specimen, insertions and deletions of DNA in and around the Staphylococcal Cassette Chromosome mec (SCCmec) element, and point mutations in mecA. Herein, we explore the complexities of …

Depletion Of The Apical Endosome In Response To Viruses And Bacterial Toxins Provides Cell-Autonomous Host Defense At Mucosal Surfaces, Keiko Maeda, Nicholas C Zachos, Megan H Orzalli, Stefanie S Schmieder, Denis Chang, Katlynn Bugda Gwilt, Michele Doucet, Nicholas W Baetz, Sun Lee, Sue E Crawford, Mary K Estes, Jonathan C Kagan, Jerrold R Turner, Wayne I Lencer

Faculty, Staff and Students Publications

Polarized epithelial cells form an essential barrier against infection at mucosal surfaces. Many pathogens breach this barrier to cause disease, often by co-opting cellular endocytosis mechanisms to enter the cell through the lumenal (apical) cell surface. We recently discovered that the loss of the cell polarity gene PARD6B selectively diminishes apical endosome function. Here, we find that in response to the entry of certain viruses and bacterial toxins into the epithelial cells via the apical membrane, PARD6B and aPKC, two components of the PARD6B-aPKC-Cdc42 apical polarity complex, undergo rapid proteasome-dependent degradation. The perturbation of apical membrane glycosphingolipids by toxin- or …

Mapk-Mediated Transcription Factor Gatad Contributes To Cry1ac Resistance In Diamondback Moth By Reducing Pxmalp Expression, Le Guo, Zhouqiang Cheng, Jianying Qin, Dan Sun, Shaoli Wang, Qingjun Wu, Neil Crickmore, Xuguo Zhou, Alejandra Bravo, Mario Soberón, Zhaojiang Guo, Youjun Zhang

Entomology Faculty Publications

The benefits of biopesticides and transgenic crops based on the insecticidal Cry-toxins from Bacillus thuringiensis (Bt) are considerably threatened by insect resistance evolution, thus, deciphering the molecular mechanisms underlying insect resistance to Bt products is of great significance to their sustainable utilization. Previously, we have demonstrated that the down-regulation of PxmALP in a strain of Plutella xylostella (L.) highly resistant to the Bt Cry1Ac toxin was due to a hormone-activated MAPK signaling pathway and contributed to the resistance phenotype. However, the underlying transcriptional regulatory mechanism remains enigmatic. Here, we report that the PxGATAd transcription factor (TF) is responsible for the …

Ppld Is A De-N-Acetylase Of The Cell Wall Linkage Unit Of Streptococcal Rhamnopolysaccharides, Jeffrey S. Rush, Prakash Parajuli, Alessandro Ruda, Jian Li, Amol Arunrao Pohane, Svetlana Zamakhaeva, Mohammad M. Rahman, Jennifer C. Chang, Artemis Gogos, Cameron W. Kenner, Gérard Lambeau, Michael J. Federle, Konstantin V. Korotkov, Göran Widmalm, Natalia Korotkova

Molecular and Cellular Biochemistry Faculty Publications

The cell wall of the human bacterial pathogen Group A Streptococcus (GAS) consists of peptidoglycan decorated with the Lancefield group A carbohydrate (GAC). GAC is a promising target for the development of GAS vaccines. In this study, employing chemical, compositional, and NMR methods, we show that GAC is attached to peptidoglycan via glucosamine 1-phosphate. This structural feature makes the GAC-peptidoglycan linkage highly sensitive to cleavage by nitrous acid and resistant to mild acid conditions. Using this characteristic of the GAS cell wall, we identify PplD as a protein required for deacetylation of linkage N-acetylglucosamine (GlcNAc). X-ray structural analysis indicates …

College Of Natural Sciences Newsletter, February 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 2

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3-4 Media Coverage of CNS
Page 5- 6 Local Boy Scouts Earn Their Chemistry Merit Badges
Page 7-8 Mount Vernon Teacher Wins 2022 South Dakota Outstanding Physical Science Teacher Award
Page 9 Middle Schoolers Visit SDSU
Page 10 Microbiology Club Tours POET
Page 11 53rd Geography Convention
Page 12 Open PRAIRIE Data

Age-Associated Gut Dysbiosis, Marked By Loss Of Butyrogenic Potential, Correlates With Altered Plasma Tryptophan Metabolites In Older People Living With Hiv, Smita Ghare, Richa Singhal, Vaughn Bryant, Sabina Gautam, Chanakya Charan Tirumala, Praneet Kumar Srisailam, Andrea Reyes-Vega, Dushan Ghooray, Craig J Mcclain, Kristi Hoffman, Joseph Petrosino, Kendall Bryant, Varan Govind, Ronald Cohen, Robert L Cook, Shirish Barve

Faculty, Staff and Students Publications

BACKGROUND: Imbalance in tryptophan (TRP) metabolism and its neuroactive metabolites, serotonin and kynurenine (KYN), is a known pathogenic mechanism underlying neurocognitive impairment. Gut microbiota plays an important role in TRP metabolism, and the production of these neuroactive molecules affects neurocognitive function. Although both HIV infection and normal aging independently induce gut dysbiosis and influence TRP metabolism, their interactive effects on compositional/functional changes in gut microbiota and consequent alterations in TRP metabolites remain largely undetermined.

METHODS: Older people living with HIV infection (PLWH, aged 50-70 years, n = 22) were enrolled in this cross-sectional pilot study. Metagenomic analysis of fecal microbiome …

Conformational Flexibility And Local Frustration In The Functional States Of The Sars-Cov-2 Spike B.1.1.7 And B.1.351 Variants: Mutation-Induced Allosteric Modulation Mechanism Of Functional Dynamics And Protein Stability, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Structural and functional studies of the SARS-CoV-2 spike proteins have recently determined distinct functional states of the B.1.1.7 and B.1.351 spike variants, providing a molecular framework for understanding the mechanisms that link the effect of mutations with the enhanced virus infectivity and transmissibility. A detailed dynamic and energetic analysis of these variants was undertaken in the present work to quantify the effects of different mutations on functional conformational changes and stability of the SARS-CoV-2 spike protein. We employed the efficient and accurate coarse-grained (CG) simulations of multiple functional states of the D614G mutant, B.1.1.7 and B.1.351 spike variants to characterize …

The Coxsackievirus And Adenovirus Receptor Has A Short Half-Life In Epithelial Cells, Poornima Kotha Lakshmi Narayan, James M. Readler, Mahmoud S. Alghamri, Trisha L. Brockman, Ray Yan, Priyanka Sharma, Vladislav Snitsarev, Katherine J.D.A Excoffon, Abimbola O. Kolawole

Department of Biology Faculty Scholarship and Creative Works

The coxsackievirus and adenovirus receptor (CAR) is an essential cellular protein that is involved in cell adhesion, cell signaling, and viral infection. The 8-exon encoded isoform (CAREx8) resides at the apical surface of polarized epithelia, where it is accessible as a receptor for adenovirus entering the airway lumen. Given its pivotal role in viral infection, it is a target for antiviral strategies. To understand the regulation of CAREx8 and determine the feasibility of receptor down regulation, the half-life of total and apical localized CAREx8 was determined and correlated with adenovirus transduction. Total and apical CAREx8 has a relatively short half-life …

Organoid Models For Infectious Disease, Sarah E Blutt, Mary K Estes

Faculty, Staff and Students Publications

Infectious diseases affect individual health and have widespread societal impacts. New ex vivo models are critical to understand pathogenesis, host response, and features necessary to develop preventive and therapeutic treatments. Pluripotent and tissue stem cell-derived organoids provide new tools for the study of human infections. Organoid models recapitulate many characteristics of in vivo disease and are providing new insights into human respiratory, gastrointestinal, and neuronal host-microbe interactions. Increasing culture complexity by adding the stroma, interorgan communication, and the microbiome will improve the use of organoids as models for infection. Organoid cultures provide a platform with the capability to improve human …

Enteroviruses And Type 1 Diabetes: Multiple Mechanisms And Factors?, Richard E Lloyd, Manasi Tamhankar, Åke Lernmark

Faculty, Staff and Students Publications

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by insulin deficiency and resultant hyperglycemia. Complex interactions of genetic and environmental factors trigger the onset of autoimmune mechanisms responsible for development of autoimmunity to β cell antigens and subsequent development of T1D. A potential role of virus infections has long been hypothesized, and growing evidence continues to implicate enteroviruses as the most probable triggering viruses. Recent studies have strengthened the association between enteroviruses and development of autoimmunity in T1D patients, potentially through persistent infections. Enterovirus infections may contribute to different stages of disease development. We review data from both …

An Exploratory Study On The Microbiome Of Northern And Southern Populations Of Ixodes Scapularis Ticks Predicts Changes And Unique Bacterial Interactions, Deepak Kumar, Latoyia P. Downs, Abdulsalam Adegoke, Erika Machtinger, Kelly Oggenfuss, Richard S. Ostfeld, Monica Embers, Shahid Karim

Faculty Publications

The black-legged tick (Ixodes scapularis) is the primary vector of Borrelia burgdorferi, the causative agent of Lyme disease in North America. However, the prevalence of Lyme borreliosis is clustered around the Northern States of the United States of America. This study utilized a metagenomic sequencing approach to compare the microbial communities residing within Ix. scapularis populations from northern and southern geographic locations in the USA. Using a SparCC network construction model, we performed potential interactions between members of the microbial communities from Borrelia burgdorferi–infected tissues of unfed and blood-fed ticks. A significant difference in bacterial composition …

Trait Energy And Fatigue May Be Connected To Gut Bacteria Among Young Physically Active Adults: An Exploratory Study, Ali Boolani, Karyn M. Gallivan, Kristin S. Ondrak, Courtney J. Christopher, Hector F. Castro, Shawn R. Campagna, Christopher M. Taylor, Meng Luo, Scot E. Dowd, Matthew Lee Smith, Lauri O. Byerley

School of Medicine Faculty Publications

Recent scientific evidence suggests that traits energy and fatigue are two unique unipolar moods with distinct mental and physical components. This exploratory study investigated the correlation between mental energy (ME), mental fatigue (MF), physical energy (PE), physical fatigue (PF), and the gut microbiome. The four moods were assessed by survey, and the gut microbiome and metabolome were determined from 16 S rRNA analysis and untargeted metabolomics analysis, respectively. Twenty subjects who were 31 ± 5 y, physically active, and not obese (26.4 ± 4.4 kg/m2) participated. Bacteroidetes (45%), the most prominent phyla, was only negatively correlated with PF. The second …

Characterizing The Amino Acid Activation Center Of The Naturally Editing-Deficient Aminoacyl-Trna Synthetase Phers In Mycoplasma Mobile, Nien-Ching Han, Arundhati Kavoor, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

To ensure correct amino acids are incorporated during protein synthesis, aminoacyl-tRNA synthetases (aaRSs) employ proofreading mechanisms collectively referred to as editing. Although editing is important for viability, editing-deficient aaRSs have been identified in host-dependent organisms. In Mycoplasma mobile, editing-deficient PheRS and LeuRS have been identified. We characterized the amino acid activation site of MmPheRS and identified a previously unknown hyperaccurate mutation, L287F. Additionally, we report that m-Tyr, an oxidation byproduct of Phe which is toxic to editing-deficient cells, is poorly discriminated by MmPheRS activation and is not subjected to editing. Furthermore, expressing MmPheRS and the hyperaccurate variants renders …

Heterologous Production Of Plant Secondary Metabolites Resveratrol And Caffeic Acid In E.Coli And Synechocystis Sp. Pcc 6803, Yong Xue

Theses and Dissertations

Caffeic acid and resveratrol are polyphenol compounds produced by plants as secondary metabolites to protect against biotic and abiotic stresses. In the last decades, numerous studies have demonstrated the beneficial effects of these compounds on human health as anticancer, antioxidant, anti-virus and anti-inflammatory agents. In plants, both caffeic acid and resveratrol are synthesized either from phenylalanine or tyrosine. Recently, heterologous production of phenylpropanoids using genetically engineered bacteria is gaining more and more attentions from industry because it can dramatically improve the yield with reduced costs. The major aim of the work is to explore the possibility of using Synechocystis or …

Distribution Of Serotypes And Antibiotic Resistance Of Invasive Pseudomonas Aeruginosa In A Multi-Country Collection, Shamima Nasrin, Nicolas Hegerle, Shaichi Sen, Joseph Nkeze, Sunil Sen, Jasnehta Permala-Booth, Myeongjin Choi, James Sinclair, Milagritos D. Tapia, Sadia Shakoor

Department of Pathology and Laboratory Medicine

Background: Pseudomonas aeruginosa is an opportunistic pathogen that causes a wide range of acute and chronic infections and is frequently associated with healthcare-associated infections. Because of its ability to rapidly acquire resistance to antibiotics, P. aeruginosa infections are difficult to treat. Alternative strategies, such as a vaccine, are needed to prevent infections. We collected a total of 413 P. aeruginosa isolates from the blood and cerebrospinal fluid of patients from 10 countries located on 4 continents during 2005-2017 and characterized these isolates to inform vaccine development efforts. We determined the diversity and distribution of O antigen and flagellin types and …