Microbiology Commons^™

Investigating The Mechanisms Of Surface Sensing Using Motility Appendages By Pseudomonas Aeruginosa Pa14, Christopher James Geiger

Dartmouth College Ph.D Dissertations

Biofilms are surfaced attached communities of cells encased in an extracellular matrix. The transition from free-swimming planktonic cells to a surface attached biofilm begins with cellular changes that occur after surface contact. This process is known as "surface sensing" and the opportunistic pathogen Pseudomonas aeruginosa PA14 uses its two motility appendages, type IV pili (T4P) and a single, polar flagellum to sense and traverse surfaces. The first cellular changes to occur within this organism upon surface contact is an increase in the second messengers cAMP and cdi- GMP. While the genes involved in surface sensing by P. aeruginosa are known, …

Borrelia Burgdorferi Plza Is A Cyclic-Di-Gmp Dependent Dna And Rna Binding Protein, Nerina Jusufovic, Andrew Krusenstjerna, Christina R. Savage, Timothy C. Saylor, Catherine A. Brissette, Wolfram Zückert, Paula J. Schlax, Md A. Motaleb, Brian Stevenson

Entomology Faculty Publications

The PilZ domain-containing protein, PlzA, is the only known cyclic di- GMP binding protein encoded by all Lyme disease spirochetes. PlzA has been implicated in the regulation of many borrelial processes, but the effector mechanism of PlzA was not previously known. Here, we report that PlzA can bind DNA and RNA and that nucleic acid binding requires c-di-GMP, with the affinity of PlzA for nucleic acids increasing as concentrations of c-di-GMP were increased. A mutant PlzA that is incapable of bind- ing c-di-GMP did not bind to any tested nucleic acids. We also determined that PlzA interacts predominantly with the …

Staphylococcus Aureus Oleate Hydratase Produces Ligands That Activate Host Ppara, Christopher D. Radka, Matthew W. Frank, Tyler S. Simmons, Cydney N. Johnson, Jason W. Rosch, Charles O. Rock

Markey Cancer Center Faculty Publications

Commensal gut bacteria use oleate hydratase to release a spectrum of hydroxylated fatty acids using host-derived unsaturated fatty acids. These compounds are thought to attenuate the immune response, but the underlying signaling mechanism(s) remain to be established. The pathogen Staphylococcus aureus also expresses an oleate hydratase and 10- hydroxyoctadecanoic acid (h18:0) is the most abundant oleate hydratase metabolite found at Staphylococcal skin infection sites. Here, we show h18:0 stimulates the transcription of a set of lipid metabolism genes associated with the activation of peroxisome proliferator activated receptor (PPAR) in the RAW 264.7 macrophage cell line and mouse primary bone marrow-derived …

Nadph Oxidase Overexpression And Mitochondrial Oxphos Impairment Are More Profound In Human Hearts Donated After Circulatory Death Than Brain Death, Nandan K Mondal, Shiyi Li, Abdussalam E Elsenousi, Aladdein Mattar, Katherine V Nordick, Harveen K Lamba, Camila Hochman-Mendez, Todd K Rosengart, Kenneth K Liao

Faculty, Staff and Students Publications

This study investigated cardiac stress and mitochondrial oxidative phosphorylation (OxPhos) in human donation after circulatory death (DCD) hearts regarding warm ischemic time (WIT) and subsequent cold storage and compared them with that of human brain death donor (DBD) hearts. A total of 24 human hearts were procured for the research study-6 in the DBD group and 18 in the DCD group. DCD group was divided into three groups (n = 6) based on different WITs (20, 40, and 60 min). All hearts received del Nido cardioplegia before being placed in normal saline cold storage for 6 h. Left ventricular …

Highlights Of How Single-Cell Analyses Are Illuminating Differentiation And Disease In The Gastric Corpus, Mahliyah Adkins-Threats, Yang-Zhe Huang, Jason C Mills

Faculty, Staff and Students Publications

Single-cell RNA-sequencing (scRNA-seq) has emerged as a powerful technique to identify novel cell markers, developmental trajectories, and transcriptional changes during cell differentiation and disease onset and progression. In this review, we highlight recent scRNA-seq studies of the gastric corpus in both human and murine systems that have provided insight into gastric organogenesis, identified novel markers for the various gastric lineages during development and in adults, and revealed transcriptional changes during regeneration and tumorigenesis. Overall, by elucidating transcriptional states and fluctuations at the cellular level in healthy and disease contexts, scRNA-seq may lead to better, more personalized clinical treatments for disease …

Antioxidant Properties Of Kombucha Beverage Infused With Ganoderma Lucidum And Green Tea From Camellia Sinensis (L.) Kuntze With Several Fermentation Times, Rizki Rabeca Elfirta, Pamungkas Rizki Ferdian, Iwan Saskiawan, Tri Hadi Handayani, Kayla Faza Gustafri Mandalika, Rini Riffiani, Kasirah Kasirah, Ukhradiya Magharaniq Safira Purwanto

Karbala International Journal of Modern Science

Kombucha is a functional beverage produced through the fermentation of infused tea or Camelia sinensis (L.) Kuntze (CS) by a symbiotic culture of bacteria and yeast. Apparently, the substrate of kombucha can be substituted to enhance its functional properties. Ganoderma lucidum (GL) is a potential substrate reported to have health benefits. This study aims to evaluate antioxidant properties by comparing different formulations and fermentation times. The formulations prepared in the present study varied in the compositions of GL and CS substrates, namely F1 (100% GL), F2 (75% GL: 25% CS), F3 (50% GL: 50% CS), F4 (25% GL: 75% CS), …

Investigating Optimal Laboratory Growth Conditions Of Gracilibacillus Halotolerans In Media Supplemented With Salt, Isaac Young

Annual Research Symposium

As interest continues to grow in the field of persister cells and their morphology, there arises an ever-evolving desire to further understand specific strains of bacteria that exemplify the qualities of seemingly anomalous survival regardless of anti-bacterial treatment. In the case of the Gracilibacillus halotolerans, a halotolerant extremophile extracted from the Great Salt Lake with known persistent characteristics, uncovering its optimal growth conditions was essential for future investigations. Identifying the optimal salinity for the growth of G. halotolerans will allow us to standardize our growth methods, uncover several mechanisms of saline tolerance, and add to future investigations of persistence with …

Interplay Of Periodontal Bacterial Metabolites In The Progression Of Coronary Artery Disease: A System Biological Approach, Janakiraman V

Annual Research Symposium

Purpose:

The purpose of this study is to investigate the intricate relationship between periodontal disease (PD) and coronary artery disease (CAD), as evidenced by epidemiological associations. Metalloproteinase inhibitor (TIMP1) plays a pivotal role in cellular signaling, differentiation, cell death, and migration by binding to target metalloproteinases, forming complexes with other molecules (collagenases) to inactivate them. However, the expression of TIMP1 is reduced in both PD and CAD, leading to an upregulation of other metalloproteinases. This research explores the hypothesis that metabolites released from (Porphyromonas gingivalis), a prevalent bacterium in atherosclerotic patients, may inhibit TIMP1, thereby influencing CAD progression. …

Correction To: Should We Use Rifampicin In Periprosthetic Joint Infections Caused By Staphylococci When The Implant Has Been Exchanged? A Multicenter Observational Cohort Study, Tobias Siegfried Kramer, Alex Soriano, Sarah Tedeschi, Antonia Chen, Pierre Tattevin, Eric Senneville, Joan Gomez-Junyent, Victoria Birlutiu, Sabine Petersdorf, Vicens Diaz De Brito, Ignacio Sancho Gonzalez, Katherine Belden, Marjan Wouthuyzen-Bakker

Division of Infectious Diseases and Environmental Medicine Faculty Papers

No abstract provided.

A Rationally Designed Antimicrobial Peptide From Structural And Functional Insights Of Clostridioides Difficile Translation Initiation Factor 1, Elvira Alanis, Faith Aguilar, Niaz Banaei, Frank B. Dean, Alexa Villarreal, Miguel Alanis, Karen Lozano, James M. Bullard, Yonghong Zhang

School of Integrative Biological & Chemical Sciences Faculty Publications

ABSTRACT: A significant increase of hospital-acquired bacterial infections during the COVID-19 pandemic has become an urgent medical problem. Clostridioides difficile is an urgent antibiotic-resistant bacterial pathogen and a leading causative agent of nosocomial infections. The increasing recurrence of C. difficile infection and antibi­otic resistance in C. difficile has led to an unmet need for the discovery of new com­pounds distinctly different from present antimicrobials, while antimicrobial peptides as promising alternatives to conventional antibiotics have attracted growing interest recently. Protein synthesis is an essential metabolic process in all bacteria and a validated antibiotic target. Initiation factor 1 from C. difficile (Cd-IF1) …

The Mrna-Lnp Vaccines - The Good, The Bad And The Ugly?, Botond Z. Igyártó, Zhen Qin

Department of Microbiology and Immunology Faculty Papers

The mRNA-LNP vaccine has received much attention during the COVID-19 pandemic since it served as the basis of the most widely used SARS-CoV-2 vaccines in Western countries. Based on early clinical trial data, these vaccines were deemed safe and effective for all demographics. However, the latest data raise serious concerns about the safety and effectiveness of these vaccines. Here, we review some of the safety and efficacy concerns identified to date. We also discuss the potential mechanism of observed adverse events related to the use of these vaccines and whether they can be mitigated by alterations of this vaccine mechanism …

Metabolic Model Predictions Enable Targeted Microbiome Manipulation Through Precision Prebiotics, Georgios Marinos, Inga K Hamerich, Reena Debray, Nancy Obeng, Carola Petersen, Jan Taubenheim, Johannes Zimmermann, Dana Blackburn, Buck S Samuel, Katja Dierking, Andre Franke, Matthias Laudes, Silvio Waschina, Hinrich Schulenburg, Christoph Kaleta

Faculty, Staff and Students Publications

While numerous health-beneficial interactions between host and microbiota have been identified, there is still a lack of targeted approaches for modulating these interactions. Thus, we here identify precision prebiotics that specifically modulate the abundance of a microbiome member species of interest. In the first step, we show that defining precision prebiotics by compounds that are only taken up by the target species but no other species in a community is usually not possible due to overlapping metabolic niches. Subsequently, we use metabolic modeling to identify precision prebiotics for a two-member Caenorhabditis elegans microbiome community comprising the immune-protective target species Pseudomonas …

A Comprehensive Analysis Of Antibiotic Resistance Genes In The Giant Panda Gut, Feilong Deng, Yanhua Han, Yushan Huang, Desheng Li, Jianmin Chai, Linhua Deng, Ming Wei, Kai Wu, Huabin Zhao, Guan Yang, Jiangchao Zhao, Ying Li, Chengdong Wang

Animal Science Faculty Publications and Presentations

In this study, we have successfully constructed a comprehensive database of metagenome-assembled genomes (MAGs) pertaining to the gut microbiota of the giant panda. Through our analysis, we have identified significant reservoirs of antibiotic resistance genes (ARGs), namely Escherichia coli, Citrobacter portucalensis, and Klebsiella pneumoniae. Furthermore, we have elucidated the primary contributors to ARGs, including Streptococcus alactolyticus and Clostridium SGBP116, in both captive and wild pandas. Additionally, our findings have demonstrated a higher prevalence of ARGs in the metagenome, with notable expression of the RPOB2 gene in S. alactolyticus. Crucially, 1217 ARGs shared homology with human gut …

Clostridium Butyricum And Carbohydrate Active Enzymes Contribute To The Reduced Fat Deposition In Pigs, Lingyan Ma, Shiyu Tao, Tongxing Song, Wentao Lyu, Ying Li, Wen Wang, Qicheng Shen, Yan Ni, Jiang Zhu, Jiangchao Zhao, Hua Yang, Yingping Xiao

Animal Science Faculty Publications and Presentations

Pig gastrointestinal tracts harbor a heterogeneous and dynamic ecosystem populated with trillions of microbes, enhancing the ability of the host to harvest energy from dietary carbohydrates and contributing to host adipogenesis and fatness. However, the microbial community structure and related mechanisms responsible for the differences between the fatty phenotypes and the lean phenotypes of the pigs remained to be comprehensively elucidated. Herein, we first found significant differences in microbial composition and potential functional capacity among different gut locations in Jinhua pigs with distinct fatness phenotypes. Second, we identified that Jinhua pigs with lower fatness exhibited higher levels of short-chain fatty …

The Diversity Of Wolbachia Across The Turtle Ants (Formicidae: Cephalotes Spp.), Corey Reese, Leland C. Graber, Manuela O. Ramalho, Corrie S. Moreau

Biology Faculty Publications

Wolbachia is a widespread and well-known bacterium that can induce a wide range of changes within its host. Ants specifically harbor a great deal of Wolbachia diversity and are useful systems to study endosymbiosis. The turtle ants (Cephalotes) are a widespread group of tropical ants that rely on gut microbes to support their herbivorous diet for their survival, yet little is known of the extent of this diversity. Therefore, studying their endosymbionts and categorizing the diversity of bacteria within Cephalotes hosts could help to delimit species and identify new strains and can help lead to a further understanding of how …

College Of Natural Sciences 2023 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 3 Department Highlights
Page 4 One Day for State
Page 5 Noble Prize Winner Speaks on Campus
Page 6-7 Faculty Excellence
Page 8-9 Student Excellence
Page 10 Outreach Program
Page 10 Events and Traditions
Page 11 Connections Abroad
Page 12 Student Spotlight
Page 13 Alumni Spotlight
Page 14 First Ever Drone Day
Page 15 Grand Opening of POET Bioproducts Center
Page 16 Work Anniversaries

Hiv-1 Mrna Knockdown With Crispr/Cas9 Enhances Neurocognitive Function, Kristen A. Mclaurin, Hailong Li, Kamel Khalili, Charles F. Mactutus, Rosemarie M. Booze

Neurology Faculty Publications

Mixed glia are infiltrated with HIV-1 virus early in the course of infection leading to the development of a persistent viral reservoir in the central nervous system. Modification of the HIV-1 genome using gene editing techniques, including CRISPR/Cas9, has shown great promise towards eliminating HIV-1 viral reservoirs; whether these techniques are capable of removing HIV-1 viral proteins from mixed glia, however, has not been systematically evaluated. Herein, the efficacy of adeno-associated virus 9 (AAV9)-CRISPR/Cas9 gene editing for eliminating HIV-1 messenger RNA (mRNA) from cortical mixed glia was evaluated in vitro and in vivo. In vitro, a within-subjects experimental design was …

Adaptive Evolution Of Surface Proteins In Microbial Pathogens: Lyme Disease Pathogens (Borreliella Sp.) And Human Immunodeficiency Virus Type 1 (Hiv-1), Li Li

Dissertations, Theses, and Capstone Projects

Cell and virion surface proteins are key to the survival and adaptation of microbial pathogens by enabling them to evade host immune responses and to persist in diverse environments. Pathogens respond to host immune pressures with genetic changes in surface proteins through mechanisms including point mutations, recombination, gene duplication and loss, and lateral gene transfer, resulting in novel antigenic variants and antigenic diversity. This continuous adaptation helps pathogens evade host immunity, leading to chronic infections and recurrent disease outbreaks. Understanding these mechanisms is vital for developing effective strategies to combat infectious diseases.

This dissertation comprises three chapters exploring the adaptive …

The Human Vaginal Microbiota: From Clinical Medicine To Models To Mechanisms, Samantha Ottinger, Clare M Robertson, Holly Branthoover, Kathryn A Patras

Faculty, Staff and Students Publications

The composition of the vaginal microbiota is linked to numerous reproductive health problems, including increased susceptibility to infection, pregnancy complications, and impaired vaginal tissue repair; however, the mechanisms contributing to these adverse outcomes are not yet fully defined. In this review, we highlight recent clinical advancements associating vaginal microbiome composition and function with health outcomes. Subsequently, we provide a summary of emerging models employed to identify microbe-microbe interactions contributing to vaginal health, including metagenomic sequencing, multi-omics approaches, and advances in vaginal microbiota cultivation. Last, we review new in vitro, ex vivo, and in vivo models, such as organoids and humanized …

Respiratory Viral Detection In The Plasma And Cerebrospinal Fluid (Csf) Of Young Febrile Infants, Erin G Nicholson, Vasanthi Avadhanula, Leila C Sahni, Laura Ferlic-Stark, Lauren Maurer, Julie A Boom, Pedro A Piedra

Faculty, Staff and Students Publications

BACKGROUND: Respiratory viral infections are common in febrile infants ≤90 days. However, the detection of viruses other than enterovirus in the blood and cerebrospinal fluid (CSF) of young infants is not well defined. We sought to quantify the occurrence of respiratory viruses in the blood and CSF of febrile infants ≤90 days.

METHODS: We conducted a nested cohort study examining plasma and CSF samples from febrile infants 15-90 days via rtPCR. The samples were tested for respiratory viruses (respiratory syncytial virus, influenza, enterovirus, parechovirus, adenovirus, bocavirus). Clinical and laboratory data were also collected to determine the presence of serious bacterial …