Microbiology Commons^™

Elucidation Of A Role In Biofilm Production For The Tyrosine Catabolism Pathway In Vibrio Cholerae And Analysis Of Reversible Phase Variation In Vibrio Vulnificus, Aheli S. Mukerji

LSU Doctoral Dissertations

Biofilms produced by the cholera pathogen Vibrio cholerae not only enhance its ability to survive in the environment but also allow pathogenic success of the bacterium. This organism also undergoes phase variation, switching between smooth and rugose colonial phenotypes, the latter forming much more vibrio polysaccharide (VPS) resulting in more robust biofilms and subsequently having an increased level of persistence. In a previous study, many genes were found to be upregulated in the transition from the smooth to the rugose phenotype. Here, several of these upregulated genes were investigated for their potential role in biofilm production, and an additional gene, …

The Astrobiological Figure Of Humboldt As Pioneer In The Rock Varnish Research, Jose Jordan-Soria

Homage to Alexander von Humboldt: Travels to and from Spain Throughout the Centuries / Homenaje a Alexander von Humboldt: Viajes hacia y desde España de todos los siglos

From Humboldt is particularly interesting -and little know- his description of mineral coatings on rocks 200 years ago, reported in his book Personal Narrative of Travels to the Equinoctial Regions of the New Continent during the years 1799-1804, co-written with Aimé Bonpland, for which is considerate the father of rock coating research. On June 5th 1799 set sail from A Coruña -Spain- to Cumaná -Venezuela- beginning five years of expedition. While they explored the Orinoco River system, in th eriver basin waterfalls, Humboldt observed the presence of dark coating depositions. He ascertained a manganese-rich accretion, reporting similar structures in other …

Commentary On Blaser's "Antibiotic Use And Its Consequences For The Normal Microbiome", Fred C. Tenover

AMR Commentary

If you have not read this eye-opening commentary by Dr. Martin Blaser about the negative impact of the widespread use of antibiotics in children, you should. The goal of giving antibiotics to children usually is to treat an infection — an earache, a respiratory tract infection, or perhaps a potentially deadly bloodstream infection. Those antibiotics, however, will often kill more than just the bacteria that are causing the infection. Humans have large quantities of “good bacteria” in our intestinal tracts, on our skin, and elsewhere on our body that play an important role in keeping us healthy.

Microbial Biosensor For Sensing And Treatment Of Intestinal Inflammation, Duolong Zhu, Jeffrey Galley, Jason Pizzini, Elena Musteata, Martin V Douglas, Walter J Chazin, Eric P Skaar, Jeffrey J Tabor, Robert A Britton

Faculty, Staff and Students Publications

Synthetic biology has enabled the development of biosensors to detect intestinal inflammation, yet few target the clinically validated biomarker of intestinal inflammation calprotectin with both diagnostic and therapeutic capabilities. Here, an optimized calprotectin biosensor is presented that leverages a zinc uptake regulator (Zur) controlled promoter coupled with a memory circuit to detect and record intestinal inflammation in vivo. The level of biosensor activation strongly correlates with calprotectin levels in the colon of two independent mouse models of colitis. Coupling of the biosensor with the production of the anti-inflammatory cytokine IL10 allowed for the resolution of chemically induced colitis, demonstrating the …

Unfolding The Mystery Of Autoimmunity: The Environmental Determinants Of Diabetes In The Young (Teddy) Study, Marian Rewers, Daniel Agardh, Suzanne Bennett Johnson, Ezio Bonifacio, Helena Elding Larsson, Patricia Gesualdo, William Hagopian, Michael J Haller, Heikki Hyöty, Randi Johnson, Richard Mcindoe, Eoin Mckinney, Jessica Melin, Åke Lernmark, Richard E Lloyd, Kristian F Lynch, Jill M Norris, Stephen S Rich, Roswith Roth, Desmond Schatz, Jorma Toppari, Eric Triplett, Kendra Vehik, Suvi M Virtanen, Anette-G Ziegler, Beena Akolkar, Jeffrey P Krischer, Teddy Study Group

Faculty, Staff and Students Publications

In 2025, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health celebrates 75 years of leadership in diabetes research. The NIDDK serves people of the U.S. affected by or at risk for many chronic diseases, including diabetes and other endocrine, metabolic, and digestive disorders, by funding innovative research to develop better treatment and prevention and a cure for these conditions. Autoimmunity that leads to type 1 diabetes or celiac disease or thyroid autoimmunity affects 1 in 20 children and adolescents in the U.S. While treatments are available, prevention of these common autoimmune …

Inhibition Of The Gsk3Β/Nav16 Complex Suppresses Early-Stage Alzheimer’S Hyperexcitability, Timothy John Baumgartner, Manuel Silva-Pérez, Zahra Haghighijoo, Nolan Michael Dvorak, Aditya Kumar Singh, Nana Aboadwe Goode, Jully Singh, Berenice Gutierrez Grebenkova, Mate Marosi, Jessica Di Re, Leandra Koff, Wissarut Wijitrmektong, Manu Bala, Hanyue Liao, Marijn Lijffijt, Adam Thomas Szafran, Michael James Bolt, Michael A Mancini, Gregory D Cuny, Diana Shu-Lian Chow, Agenor Limon, Jeannie Chin, Fernanda Laezza

Faculty, Staff and Students Publications

Introduction: Network hyperexcitability (NH) is observed in patients with early-stage Alzheimer's disease (AD), emerging decades before cognitive decline. A key molecular determinant of NH is voltage-gated Na+ channel 1.6 (Nav1.6), which mediates action potential firing in CA1 hippocampal neurons. Ameliorating NH through inhibition of the glycogen-synthase kinase 3β (GSK3β/Nav1.6 complex may provide immediate benefits to cognition and memory and slow AD progression.

Methods: Hight-throughput virtual screening and multiple in vitro biological assays were utilized to identify compound 1063. Patch-clamp electrophysiology and electroencephalogram recordings were utilized to functionally assess 1063 in models of AD neuropathology.

Results: Building on previous studies identifying …

Decoding Metastatic Microenvironments Through Single-Cell Omics Reveals New Insights Into Niche Dynamics And Tumor Evolution, Fengshuo Liu, Xiang H-F Zhang

Faculty, Staff and Students Publications

Metastasis is the predominant cause of cancer mortality, primarily driven by complex tumor-host interactions within specialized metastatic niches. Recent advances in single-cell technologies have provided unprecedented insights into metastatic niche formation, evolution and function, including how primary tumors precondition distant organs for metastases and how disseminated tumor cells dynamically interact with host cells to modulate their environments. Integrated single-cell studies across multiple cancer types have also revealed divergent and convergent metastatic adaptation strategies. These findings collectively highlight metastasis as a dynamic, cooperative process shaped by intricate tumor-host interactions, and provide a foundation for novel therapeutic strategies targeting components of the …

Association Of Statin Use On Survival Outcomes Of Patients With Early-Stage Her2-Positive Breast Cancer In The Aphinity Trial, Christian Maurer, Elisa Agostinetto, Lieveke Ameye, Matteo Lambertini, Samuel Martel, Noam Ponde, Mariana Brandão, Francesca Poggio, Arlindo Ferreira, Rachel Schiff, Carmine De Angelis, Richard D Gelber, Susan Dent, Christoph Thomssen, Martine Piccart, Evandro De Azambuja

Faculty, Staff and Students Publications

Purpose: There is evidence that statins might improve the outcome of patients with breast cancer. The role of statins in patients with early HER2-positive breast cancer is unknown. Therefore, we explored the association between statin use and survival outcomes in early HER2-positive breast cancer patients in the phase III APHINITY trial (adjuvant pertuzumab/trastuzumab).

Methods: All patients (intent-to-treat population, n = 4804) were included (6.2 years median follow-up database). The primary objective was to investigate the association of statin use on invasive disease-free survival (IDFS), distant relapse-free interval (DRFI), and overall survival (OS). Patients who received statins at baseline, or started …

Reaction Control Mechanism In Deoxyuridine 5'-Triphosphate Nucleotidohydrolase, Aaron Delay

School of Biological Sciences: Dissertations, Theses, and Student Research

Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) is an enzyme involved in the pyrimidine biosynthesis pathway, a key component of cellular DNA metabolism. It regulates intracellular uracil carrying triphosphate levels by hydrolyzing dUTP, thereby providing a substrate for thymidylate synthase (TS). The effective inhibition of dUTPase is expected to enhance TS-targeted chemotherapy by promoting thymine-less apoptosis.

Although the reaction mechanism of dUTPase has been studied, the human nuclear homotrimeric form remains complex, as all three subunits cooperatively form a single active site. As a result, the detailed molecular dynamics of its catalysis are still not fully understood. In this study, I investigated the …

Phytochemical Analysis And Antimicrobial Activity Of Micromeria Barbata Leaf And Stem Extracts Against Pseudomonas Aeruginosa: Insights From Molecular Docking And In Vitro Assays, Shiraz Rawas, Dalia El-Badan, Nawal Al Hakawati

BAU Journal - Science and Technology

The present study provides the characterization of the phytochemical content and the antibacterial activity of ethanolic extracts from the leaves (LM) and stems (SM) of Micromeria barbata (M.barbata) against Pseudomonas aeruginosa . Important functional groups were determined by analyzing the FTIR spectra of LM and SM. The phytochemical profiles were analyzed by GC-MS, and these characterized the chemicals according to retention periods and peak regions. The binding affinities of discovered compounds with the P. aeruginosa LasR and PqsD proteins were evaluated using molecular docking approach. Assays for biofilm formation, MIC, MBC, and agar well diffusion were used to assess the …

Knowledge Of Hiv Transmission And Prevention Among University Students In Pakistan: A Cross-Sectional Study, Muhammad Saleem, Sajid Masood, Shahid Hussain

Journal of Bioresource Management

HIV/AIDS remains a significant public health problem internationally, with young adults being especially at risk because of behavioral and knowledge deficits. In Pakistan, cultural inhibitions and suboptimal health education are the main reasons for limited awareness, particularly among university students. This study had the objectives of determining the knowledge level about HIV transmission and prevention among undergraduate students in Kohsar University Murree (KUM) and to investigate correlations with salient demographic variables. A cross-sectional survey was carried out among 510 students aged 18-27 years through a pre-validated, standardized questionnaire with 12 knowledge-based items. Descriptive statistics and Chi-square tests were utilized to …

Erratum: Culture Harder: Use More Specimen To Increase Methicillin-Resistant Staphylococcus Aureus Culture Yield Relative To Pcr, Arvette E. Mitchell, Arpit P. Patel, Jennifer Dicandilo, Zachary W. Rebollido, Matthew Pettengill

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

During the copyediting stage of production an error was introduced to the title of this article. This resulted in misspelling of the word ‘specimen’ in the title of the published version of the record. The correct title is ‘Culture harder: use more specimen to increase methicillin-resistant Staphylococcus aureus culture yield relative to PCR.’

Previously the title was ‘Culture harder: use more specimens to increase methicillinresistant Staphylococcus aureus culture yield relative to PCR.’

The version of record was updated to reflect this correction.

We apologise for the inconvenience.

Soil Degradation Of Solvent-Cast Pha Films Produced By Bacillus Tequilensis Pwf Using Waste Polyethylene Terephthalate (Pet), Rafeya Sohail, Rida Batool, Nazia Jamil

Journal of Bioresource Management

Polyhydroxyalkanoate (PHA) aliphatic polymers however efficiently biodegradable, still pose a contradiction with the principles of green chemistry. Use of bacterial strains capable of degrading synthetic plastics for the production of biopolymers i.e., PHAs may aid in reduction of plastic pollution. Bacterial strains PWA; Bacillus subtilis (MH142143), PWF; Bacillus tequilensis (MH142145), and PWG; Bacillus safensis (MH142146) were grown on waste shredded PET and PET flakes. Highest bioconversion of PET to PHA was observed using PET flakes. Strain PWF produced 40.47 % (0.815 g/L) and 31.80 % (0.626 g/L) PHA using PET flakes and shredded PET at 48 h, respectively. Whereas highest …

Phylogenetic Analysis Of Ftsz In Wolbachia: Implications For Host Specificity, Anwar Rovik, Ayu Rahayu

Makara Journal of Science

Wolbachia are the most prevalent and successful endosymbiont in invertebrates and are categorized into 21 supergroups based on genetic phylogeny. The filamenting temperature-sensitive Z (FtsZ) protein is essential for bacterial cell division and is hypothesized to play a role in Wolbachia's control of host reproduction. However, despite FtsZ's importance, little is known about its diversity and function within Wolbachia. This study investigated the variability of the FtsZ-encoding gene among Wolbachia strains and their hosts. FtsZ gene sequences were retrieved from the National Center for Biotechnology Information database, and representative sequences were randomly selected from each host species and analyzed …

Isolation And Selection Of Bacillus Spp. As Candidate Probiotics For Use In Chickens, Adilah Adawiah, Komang Gede Wiryawan, Anja Meryandini

Makara Journal of Science

The growth rate of chickens can be improved by using probiotics as alternatives to antibiotics. Bacillus spp. as probiotics are particularly beneficial due to ability to form spores, which remain stable as commercial products over extended periods. This study aimed to isolate and select Bacillus spp. from Jasinga soil as probiotic candidates for chickens. A total of 15 isolates obtained of these, 12 were identified as Bacillus spp based on microscopic observations and screening test including ascertaining hemolysis, protease, amylase, and cellulase activities. Only six isolates exhibited gamma hemolysis and the ability to hydrolyze proteins, starch, and cellulose. Isolates BTJ1.1, …

First Insight On The Genesis Of Iron Oxide-Hydroxide Biospeleothems In Rancho Chico Lava Tube, Mexico, Rafael López-Martínez, Elizabeth Solleiro-Rebolledo, Rocio Alcántara-Hernández, Teresa Pi Puig, Sergey Sedov, Daisy Valera Fernández, M. Nayeli Luis-Vargas, Yasmany Lima Vera, Jesús Solé, Ramon Espinasa-Pereña

International Journal of Speleology

Iron is a common element in lava tube systems, typically observed as thin crusts or inferred from the reddish coloration of secondary mineral deposits. In this study, we describe iron oxide-hydroxide biospeleothems discovered in the Rancho Chico Lava Tube, located within the Xalapa Monogenetic Volcanic Field in Mexico. We adopt an integrative approach combining petrography, soil micromorphology, scanning electron microscopy, mineralogy, and 16S rRNA gene metabarcoding. DNA sequencing reveals the presence of microorganisms such as Acidithiobacillus, Gallionella, and members of the Leptospirillaceae family, which may be involved in the oxidation of Fe²⁺ within the lava tube. The source …

Detection Of Quorum-Sensing Molecules In The Mutualistic Bacteria Vibrio Fischeri Exposed To Simulated Microgravity Using Cell-Based Biosensors., Paulina Slick, Maria C. Tobarra, Alba A. Chavez, Hugo Castillo

Beyond: Undergraduate Research Journal

Bacteria flourish in multiple environments when communicating with each other in a process known as Quorum Sensing. This process is accomplished by the production of small signaling molecules referred to as Autoinducers (AI). This communication allows the bacteria to alter their gene expression in an effort to regulate their cell number, behavior, community formation and virulence. The space environment provides stressful conditions for bacteria as they are exposed to radiation and Microgravity (µG or MG) altering synthesis and concentration of Autoinducers. The purpose of this research was to expose the model system Vibrio fischeri to simulated microgravity using the recently …

Crayfish Microhabitats Provide A Close Association With Benthic Microbiomes To Support Cleaning Symbionts., Kyle J. Harris, John Hoverson, Matthew Becker, Matthew M. Cooke Mr

NEXUS: The Liberty Journal of Interdisciplinary Studies

Stream ecosystems promote variable microhabitats along a longitudinal gradient. These microhabitats support dynamic biotic assemblages. One such microhabitat in freshwater streams involves the external surface of crayfish. We investigated the microbiome of crayfish exoskeletons and the surrounding environment (water and substrate) in association with the presence and abundance of crayfish cleaning ectosymbionts (branchiobdellidans). These ectosymbionts actively consume the biofilm on crayfish as they live and reproduce in association with crayfish microhabitats. Sequenced microbes of the environment and crayfish were compared for dominant taxa. While the sample types (water, substrate, and crayfish) had significantly different microbiomes, there was not a significant …

Identification Of Host Nuclear Factors Exploited By Kshv Lana To Maintain Latency, Anandita Ghosh

USF Tampa Graduate Theses and Dissertations

Kaposi’s Sarcoma Associated Herpes Virus (KSHV or HHV-8) is a γ-herpesvirus implicated in multiple lymphoproliferative human cancers and immune dysregulatory diseases. Like other herpesviruses, KSHV has a biphasic mode of infection primarily orchestrated by two viral proteins: the Latency-Associated Nuclear Antigen (LANA), which promotes viral persistence through latency, and the Replication and Transcription Activator (RTA), which triggers lytic reactivation. During latency, the KSHV genome exists as a highly heterochromatinized, extrachromosomal episome in the nucleus, which can be reverted to euchromatin in response to certain stimuli, like stress. KSHV has evolved to exploit numerous host proteins to orchestrate its lifecycle, especially …

The Impact Of Polymycovirus 1 On Aspergillus Fumigatus Pathogenesis During Lung Infection, Alexander W. Rapp

Dartmouth College Ph.D Dissertations

The genus Aspergillus comprises over 250 species of fungi. Within this genus, only a handful of species cause disease in humans. One species is Aspergillus fumigatus (A.f.), an environmentally ubiquitous, saprophytic fungal pathogen. Lung infections due to A.f. range from invasive infection to allergic forms of the disease. Allergic bronchopulmonary aspergillosis (ABPA) is one of the most severe forms and presents as a hypersensitivity that often results in off-target damage to the surrounding airways. Patients with ABPA are sensitized to fungal antigens and this is commonly seen in cystic fibrosis and genetic predispositions. Recent data from our lab shown how …