Biology Commons^™

Biochemical Characterization Of Fsa1572 From Fervidibacter Sacchari, The First Hyperthermophilic Gh50 With Β-1, 4-Glucanase Activity, Jonathan Covington

UNLV Theses, Dissertations, Professional Papers, and Capstones

The bacterium Fervidibacter sacchari is an aerobic hyperthermophile that catabolizes various polysaccharides and is the only cultivated member of the class Fervidibacteria within the phylum Armatimonadota. Among its glycoside hydrolase (GH) cache is an enzyme from GH family 50 (GH50), an understudied family with only 25 characterized representatives and two known activities from 1,518 predicted members in the Carbohydrate-Active EnZyme (CAZy) Database. Here, we expressed, purified, and functionally characterized an extracellular GH50 from F. sacchari called Fsa1572. Using colorimetric assays, we show it has novel β-1,4-glucanase activity and only weak agarose activity that is typical for GH50 enzymes. The purified …

Long-Range Regulation By The Shigella Virulence Gene Regulator, Virb, Cody Cris

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nucleoid-structuring proteins (NSPs) in bacterial cells can exert gene regulatory effects over great distances on DNA. This contrasts with the traditional view of bacterial transcriptional regulation, where transcription factors bind cis-acting regulatory sites proximal (<250 bp) to promoters to influence gene expression. In Shigella species, the histone-like nucleoid-structuring protein (H-NS) transcriptionally silences many genes on the large (~220 kb) virulence plasmid. During host colonization, however, silencing by H-NS is alleviated by the anti-silencer protein, VirB, which remodels the H-NS:DNA complex. This transcriptional anti-silencing is mediated by VirB:DNA interactions and the modulation of DNA supercoiling, which lead to the up-regulation of virulence genes. VirB is a central regulator of Shigella virulence, but the mechanistic basis for transcriptional regulation is incompletely characterized. Here, I focus on the potential for VirB to regulate transcription from remotely located DNA binding sites. Employing complementary in vivo approaches, I assessed the spatial stringency of the VirB binding site and elucidated how varying cellular VirB levels impacts regulation over different distances. I also evaluated how a molecular roadblock on DNA influences remote regulation by VirB. Additionally, I developed control tools to validate the ability of VirB to spread along DNA, an activity of VirB that putatively drives transcriptional regulation. These data are consistent with transcriptional anti-silencing being driven by VirB spreading along DNA. Overall, these findings highlight how VirB is not a conventional transcriptional regulator and broaden our perspective on transcriptional control in bacteria. Furthermore, this work contributes to our understanding of long-range gene regulatory effects, which are frequently overlooked and poorly characterized in bacteria.

Poop! There It Is! Anti-Germinants And Biological Variables As Modulators Of Clostridioides Difficile Infection (Cdi), Jacqueline Renee Phan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides difficile infection (CDI) is a major cause of antibiotic-associated diarrhea. Due to its insidious nature, the Centers for Disease Control and Prevention (CDC) has declared CDI an urgent threat. A key characteristic of C. difficile is its ability to form dormant spores that act as the infectious vehicles for disease. In the gut, spores recognize bile salts to germinate into toxin-producing cells.Dysbiosis of the gut microbiome is a key factor in allowing the C. difficile spores to germinate. Normal gut microbiota naturally protects from CDI. However, biological variables such as diet and sex have been found to modulate to …

Nanosecond Pulsed Electric Field Modulates Electron Transport And Mitochondrial Structure And Function, Lucas Nelson Potter

Biomedical Engineering Theses & Dissertations

Pulsed power treatment has been used to induce regulated cell death (RCD) in cells or ablate tumors in animals. A subset of pulsed power as electroporation with high voltage and pulse duration of milliseconds is used for biomedical treatment to induce pores in the plasma membrane of cells. Nanosecond Pulsed Electric Fields (nsPEFs)– an extension of electroporation, uses waveforms with pulse durations on the order of 10-900 nanoseconds. nsPEF treatment has demonstrated intracellular effects for potential biomedical applications. In this work, nsPEF treatment is used to demonstrate changes that affect viability, plasma membrane permeability ROS (Reactive Oxygen Species) in the …

Gonads Without Glp-1: Silencing Glp-1 In The Male Somatic Gonad In Caenorhabditis Elegans, Matthew Titus

Undergraduate Theses

In C. elegans, the gene glp-1 encodes for a Notch receptor called GLP-1, one of two found in C. elegans’ genome. The gene has been previously implicated in the development of the hermaphroditic germline as well as playing a role in the mitosis/meiosis decision. Genetic screening has further identified it as potentially playing a role in the development of the male somatic gonad, making it an ideal candidate for a reverse genetic. We did this by silencing glp-1 and observing if any alterations to the gonad’s phenotype occur.

Normally this could be done by performing a gene knockout. …

From Deep Mutational Mapping Of Allosteric Protein Landscapes To Deep Learning Of Allostery And Hidden Allosteric Sites: Zooming In On “Allosteric Intersection” Of Biochemical And Big Data Approaches, Gennady M. Verkhivker, Mohammed Alshahrani, Grace Gupta, Sian Xiao, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

The recent advances in artificial intelligence (AI) and machine learning have driven the design of new expert systems and automated workflows that are able to model complex chemical and biological phenomena. In recent years, machine learning approaches have been developed and actively deployed to facilitate computational and experimental studies of protein dynamics and allosteric mechanisms. In this review, we discuss in detail new developments along two major directions of allosteric research through the lens of data-intensive biochemical approaches and AI-based computational methods. Despite considerable progress in applications of AI methods for protein structure and dynamics studies, the intersection between allosteric …

Novel Plant Peroxidase Investigation For Use In Various Biochemical And Practical Applications, Sally Hess

Liberty University Research Week

Undergraduate

Basic

Characterization Of A Sas3 Homolog In The Human Pathogenic Yeast Cryptococcus Neoformans, Lillianne Bartone

Liberty University Research Week

Undergraduate

Basic

Locomotor Biomechanics In Stream Gobies, Rhinogobius Sp.: Functional Performance Of Waterfall-Climbing Behavior, Ernest W. Murphy

Student Scholar Showcase

Gobiidae is the taxonomic classification of a large fish family comprising over 2,000 species. A few goby species have the unique ability of scaling waterfalls using pelvic fins that are fused into a suction disc (pelvic sucker) located on the ventral side of the body, aiding them in upstream migration to freshwater feeding and reproduction locations. This study aimed to investigate the locomotor biomechanics of Rhinogobius goby fish due to the lack of literature in the area. In particular, climbing performance variables (pressure differential, force, endurance, and kinematics of attachment), pelvic sucker fatigability, and ontogenetic patterns of physical development and …

The Application Of Microbial Source Tracking To Aid In Site Prioritization For Remediation In Lower Michigan, John J. Hart

Masters Theses

Non-point source fecal pollution is a threat to both the environment and public health. Climate change, aging infrastructure, and intensified agricultural practices are predicted to accentuate this issue. In Michigan, due to the high instance of aging infrastructure and intensified agriculture, non-point source fecal pollution has caused many waterbodies to exceed the state standards posing a risk to recreational activities and source water. Due to this threat, there is an increased effort to identify and remediate these sources. My study focused on improving the identification of non-point source fecal pollution through a combination of culture-based and molecular fecal indicator bacteria …

Serving Justice Case By Case, Michael Becker

WRIT: Journal of First-Year Writing

Forensic Science is an integral part of serving justice in today's society, and majority of the world has little understanding of what forensics is. Read this article on forensic science and how it relates to writing in today's world.

In Vitro Characterization Of Fluorogenic Chemical Tools To Study Human Carboxylesterases (Cess), Taylor Parish Spidle

Undergraduate Honors Theses

Human carboxylesterases (CESs) are enzymes that are responsible for the metabolism of many important pharmaceuticals. Although CESs are key players in the hydrolysis of many ester-containing drugs, they remain understudied. Our group hypothesizes that this is primarily because there are few methods capable of reporting activity in live cells. Here, I report a new series of fluorogenic chemical tools to study the CES activity of one of the two major CESs in humans, CES1, in live cells. MCP-Me, MCP-Et, and MCP-iPr utilize the same carbonate group of a previously developed chemical tool in our group, FCP-1, and work to mimic …

Characterization And Genomic Analysis Of Two Escherichia Coli O157:H7 Bacteriophages Isolated From Pigeons, Mohamad I. Alolama

Dissertations

Enterohemorrhagic Escherichia coli, also known as EHEC, is a subset of Shiga toxin-producing E. coli (STEC), and it has recently been identified as one of the principal foodborne pathogens. E. coli O157:H7 is the most important serotype of STEC for its role in causing foodborne illnesses. E. coli O157:H7 could cause various gastroenteritis symptoms such as diarrhea, hemolytic uremic syndrome, hemorrhagic colitis, and thrombotic thrombocytopenic purpura and may cause death. Elimination of E. coli O157:H7 during food processing and storage is a possible solution. Bacteriophages have a significant impact on bacterial populations in nature due to their ability to …

Length Of Course-Based Undergraduate Research Experiences (Cure) Impacts Student Learning And Attitudinal Outcomes: A Study Of The Malate Dehydrogenase Cures Community (Mcc), Sue Ellen Dechenne-Peters, John Rakus, Amy D. Parente, Tamara L. Mans, Rebecca Eddy, Nicole Galport, Courtney Koletar, Joseph J. Provost, J. Ellis Bell, Jessica K. Bell

Biology: Faculty Publications

Course-based undergraduate research experiences (CUREs) are laboratory courses that integrate broadly relevant problems, discovery, use of the scientific process, collaboration, and iteration to provide more students with research experiences than is possible in individually mentored faculty laboratories. Members of the national Malate dehydrogenase CUREs Community (MCC) investigated the differences in student impacts between traditional laboratory courses (control), a short module CURE within traditional laboratory courses (mCURE), and CUREs lasting the entire course (cCURE). The sample included approximately 1,500 students taught by 22 faculty at 19 institutions. We investigated course structures for elements of a CURE and student outcomes including student …

College Of Natural Sciences Newsletter, February 2023, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 4, Issue 1

Page 1 Dean's Message
Page 2 Awards and Recognition
Page 3-4 Nobel Recipient Visits Campus
Page 4 Adopting the Pantry
Page 5 Growing a Recruitment Mindset
Page 6 February Outreach Events
Page 7 Media Coverage of CNS
Page 8 Open PRAIRIE Data
Page 9 54th Geography Convention, and Tom Loveland EROS Geography Scholarship
Page 10 Photos of Dr. Carolyn Bertozzi's Visit

Detection And Capture Of Nitrogen Fixing Bacteria From Soil And Roots Using Plant Specific Lectins, Alana Horton

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Diazotrophs increase plant productivity by providing ammonia directly to plants in the rhizosphere or through association with the roots (Sun et al., 2021). Leveraging diazotrophs can aid in the reduction or application of harmful synthetic nitrogen fertilizers. This thesis aims to use plant root proteins, or lectins, to more rapidly recover viable diazotrophs that are likely to associate with crops. In this study, lectins, are used to recover bacteria from bulk soil by taking advantage of the binding relationship between lectins and bacterial cell surface polysaccharides. When commercially-available lectins were used with a magnetic pulldown to separate the lectin, bacterial …

College Of Natural Sciences Newsletter, November 2022 - January 2023, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volme 3, Issue 7

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Sioux Falls Middle School Visit
Page 4 Bio-Micro Day of Scholars
Page 5 GIS Day at USGS EROS
Page 6 Indigenous People's Festival, & Visiting Jack's Imagination Lab
Page 7 Media Coverage of CNS, & Research Highlights from Geography & Geospatial Sciences
Page 8 Media Coverage of CNS. cont.
Page 9 Open PRAIRIE Data
Page 10 Recent Publications from CNS
Page 11 Recent Publications from CNS. cont.
Page 12 CNS Holiday Snapshots
Page 13 & 14 Fall 2022 Dean's List
Page 12-14 Fall 2022 Outreach …

Genetic Determinants Involved In Acquisition Of Iron In The Opportunistic Pathogen Mycobacterium Abscessus, Manal F. Farhat

Dissertations, Theses, and Capstone Projects

The opportunistic pathogen Mycobacterium abscessus subsp. abscessus (Mab) has become an emerging public health threat due to the increasing number of Mab-associated chronic pulmonary disease cases. Infection cure rates are only 50% due to the complex resistance of Mab to most antimicrobial drugs and chemotherapy.

Deeper knowledge of Mab biology is needed to illuminate potential candidates for development of improved therapeutics against Mab infections. The ESX-3 type VII protein secretion system of Mab plays an important role in host inflammatory and pathological responses during infection.

In this study, we demonstrate a functional link between the ESX-3 secretion …

Methylene Blue Inhibits Cromakalim-Activated K+ Currents In Follicle-Enclosed Oocytes, Dmytro Isaev, Keun-Hang Susan Yang, Georg Petroianu, Dietrich Ernst Lorke, Murat Oz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The effects of methylene blue (MB) on cromakalim-induced K⁺ currents were investigated in follicle-enclosed Xenopus oocytes. In concentrations ranging from 3–300 μM, MB inhibited K⁺ currents (IC₅₀: 22.4 μM) activated by cromakalim, which activates K_ATP channels. MB inhibited cromakalim-activated K⁺ currents in a noncompetitive and voltage-independent manner. The respective EC₅₀ and slope values for cromakalim-activation of K⁺ currents were 194 ± 21 µM and 0.91 for controls, and 206 ± 24 µM and 0.87 in the presence of 30 μM MB. The inhibition of cromakalim-induced K⁺ currents by MB was not …

Change And Stasis Of Distinct Sediment Microbiomes Across Port Everglades Inlet (Pei) And The Adjacent Coral Reefs, Lauren E. Krausfeldt, Jose V. Lopez, Catherine Bilodeau, Hyo Won Lee, Shelby L. Casali

Biology Faculty Articles

Deep water ports are human built coastal structures that by definition welcome ship traffic and disturbance. Evidence is accumulating that enhanced port activities such as dredging or deepening have negatively affected nearby natural habitats. Port Everglades Inlet (PEI) is a large active South Florida cargo port for over two million people and lies adjacent to coral reefs, dwindling mangroves, and recreational beaches. In this study, the microbial communities of PEI and adjacent reef sediments were characterized to serve as indicators for change due to dredging and assess anthropogenic influence on these sensitive ecosystems by sequencing the V4 region of 16S …

Molecular Regulation Of The Salicylic Acid Hormone Pathway In Plants Under Changing Environmental Conditions, Christina A. M. Rossi, Eric J. R. Marchetta, Jong Hum Kim, Christian Castroverde

Biology Faculty Publications

Salicylic acid (SA) is a central plant hormone mediating immunity, growth, and development. Recently, studies have highlighted the sensitivity of the SA pathway to changing climatic factors and the plant microbiome. Here we summarize organizing principles and themes in the regulation of SA biosynthesis, signaling, and metabolism by changing abiotic/biotic environments, focusing on molecular nodes governing SA pathway vulnerability or resilience. We especially highlight advances in the thermosensitive mechanisms underpinning SA-mediated immunity, including differential regulation of key transcription factors (e.g., CAMTAs, CBP60g, SARD1, bHLH059), selective protein–protein interactions of the SA receptor NPR1, and dynamic phase separation of the recently identified …

Interferon Gamma Signaling In Ovarian Cancer Cells, Bijaya Gaire

Theses and Dissertations

Interferon gamma (IFNγ) is a pleiotropic cytokine that can have, depending on the cellular and molecular context, both anti-tumor and pro-tumorigenic functions. IFNγ expression can be induced in cancer cells in response to radiation therapy or immune checkpoint blockade used in cancer treatment. We have previously shown that IFNγ induces expression of the Bcl3 proto-oncogene in ovarian cancer (OC) cells, resulting in their increased proliferation and migration, but the mechanisms are unknown. Here, I demonstrate that the IFNγ-induced Bcl3 expression is dependent on JAK1 and STAT1 signaling, and on p65 NFkB. Furthermore, my data show that the IFNγ-induced Bcl3 expression …

Role Of Integrins In Hiv Infection Of Resting Cd4+ T Cells Stimulated By Intestinal Endothelial Cells, Anding Shen, Sarah Logan, Tim Kim, Zihan Zhang

Summer Research

Eradicating HIV remains a formidable challenge due to the persistence of latent reservoirs within resting CD4+ T cells. Intestinal endothelial cells (IECs) have been shown to promote HIV infection and latent reservoir formation in resting CD4+ T cells. Our research investigates the role of integrins and their ligands, specifically ICAM, VCAM, and MAdCAM, in resting T cells and their impact on productive and latent HIV infection. Findings reveal that VCAM stimulation was the most effective in promoting productive HIV infection. MAdCAM and ICAM had minimal effect. Cytokine IL-6 consistently displayed synergy with all CAMs, amplifying effects on productive HIV infection. …

Regulation Of P53 By Trpm6 And Trpm7, Thomas Whitbread

Theses and Dissertations

TRPM6 and TRPM7 are two divalent metal cation channels that also possess a serine/threonine kinase domain. They both play critical roles in cellular and organismal metal homeostasis, and are necessary for proper embryonic development and human health. They may function independently in homomeric units, or act together as heterotetramers that display unique characteristics compared to the homomeric channels. These channel-kinases have increasingly been linked to cancer, displaying altered expression levels in a variety of human cancers and contributing to disease progression. Prior work has shown that TRPM6 and TRPM7 can participate in cancer-related signaling pathways. Here, the potential for TRPM6 …

Trichloroethylene (Tce) And Metabolite S-(1,2-Dichlorovinyl)-L-Cysteine (Dcvc) Alters Pregnancy Mediators In Rat Amniotic Fluid And Thp-1 Cells, Audrey Luce, Lyric Johnson, Karena Moleakunnel, Eleanor Scheeres, Emily Schellenboom, Sean Harris, Erica Boldenow

Summer Research

• Proinflammatory cytokines, such as TNF-α recruit immune cells to help fight infection and aid in cervical ripening (i.e. dilation).

• Matrix metalloproteinases (MMPs) such as MMP-9 help with rupture of the gestational membranes (i.e. breaking of the water).

• Prostaglandins, such as PGE2 contribute to myometrial contractions and labor induction.

• Working pregnant women are exposed to both toxicants and pathogens which can contribute to adverse birth outcomes such as preterm birth.

Botanical Assessment Of Remnant Floodplain Habitats Along Plaster Creek, Kent County, Michigan: Assessing Changes Since The 1890s, Haley R. Weesies, Garrett Crow, David Warners

Faculty and Professional Research

Plaster Creek, a tributary of the Grand River, drains a 58-square mile watershed in Kent County, Michigan. Its headwaters originate in the agriculturally dominated southwestern portion of the county, and then it meanders through residential, commercial, and urban areas of Kentwood and Grand Rapids before it empties into the Grand River about one mile south of downtown Grand Rapids. Much of Plaster Creek’s original floodplain, like the rest of its watershed, has been drastically altered and degraded over time due to the development of residential neighborhoods, commercial properties, agriculture, and industrial zones. Floodplains house unique assemblages of Michigan’s native biodiversity …

Tissue And Sex-Dependent Regulation Of Innate Immunity And Rna Editing In Mice, Kelsey R. Kendrick

Graduate Theses/Dissertations

Inflammation occurs as a result of insult or infection within the body. Individual cells respond to inflammation by upregulating genes that help mediate the immune response, such as ADAR1. ADAR1 helps regulate the immune response but also catalyzes a process called RNA editing. RNA editing alters the sequence of select mRNAs to alter the encoded proteins. The result is altered function of the encoded protein, which is often beneficial for the cell. Our goal was to determine how inflammation affects the function of ADAR1. Since we know that the effects of inflammation vary between different organs and sexes, we examined …

Molecular Investigation Of Minor Genomic Populations And Biological Exposures In Human Health, Brandon Ned Johnson

Dissertations and Theses

The study of genetics has contributed to countless discoveries related to human health and disease. However, the complexities of human biology reside not only in the genome but also in the contributions from environmental exposures, as measured via the classical twin design. To understand the influence of biological exposures, I implemented study designs to explore both the health associations and propagation of foreign genetic material. Microchimerism has been studied for association with several clinical conditions, and I further investigated if male microchimerism could elucidate the etiology of Mayer-Rokitansky-Küster-Hauser syndrome. Prevalence of male microchimerism in women with no history of pregnancy …

Analyzing Mex67 Interaction With The Ssa4 Transcript For Selective Export, Gretchen E. Stalnaker, Rebecca Adams

Science University Research Symposium (SURS)

In eukaryotic cells, such as the budding yeast Saccharomyces cerevisiae, mRNA export is the essential process in which mature mRNA is transported from its site of production, the nucleus, through the nuclear pore complex (NPC) to the cytoplasm, where it can then be translated into protein. This is accomplished when a transcript interacts with the mRNA export protein Mex67, which shuttles the message across the NPC. When the cell is under conditions of stress, such as heat shock, most mRNA export is prohibited, allowing for selective gene expression that prioritizes cell recovery. Specifically, SSA4, which encodes a protein that …

Testing Ssa4:Ade3 Reporters For Mcs Screening, Karah Edmonds, Rebecca Adams

Science University Research Symposium (SURS)

In eukaryotic cells, after transcription, mRNA is escorted from the nucleus to the cytoplasm to be translated. This process, called mRNA export, is essential for gene expression. However, when the cell exists in stressful conditions, mRNA export becomes regulated, and only select transcripts, including the stress-responsive SSA4 mRNA, can be exported. This project aims to uncover the mechanism of selective SSA4 mRNA export by generating a reporter that enables phenotypically visible expression under stressful conditions. Specifically, the ADE3 ORF was placed under the regulatory sequence of SSA4, which was anticipated to induce a red color for colonies only following stress. …