Biology Commons^™

Understanding Cytochrome C Maturation In Anaerobic Archaea, Blake Wojciechowski

Biological Sciences Undergraduate Honors Theses

Methanoperedens nitroreducens (MPEBLZ), an archaeal methanotroph and close relative of Methanosarcina acetivorans, contain numerous cytochrome c proteins. However, difficulty in using these organisms as a model for cytochrome cresearch has created a pressure to express cytochrome c proteins in an organism that is much easier to work with. A punitive cytochrome c protein (MPEBLZ_04274) from M. nitroreducens was attempted to be cloned into a model methanogen M. acetivorans as well as Escherichia coli. Cytochrome c proteins are important for many metabolic processes within anaerobic archaea. In order for a mature cytochrome c to be formed heme must …

Toxicity Analysis Of 2’-Deoxyguanosine-N2-6-Aminopyrene And 2’-Deoxyguanosine-N2-8-Aminopyrene In Escherichia Coli, Emily Janeiro

Honors Scholar Theses

Cancer is a disease that stems from genomic errors that are not corrected properly by cellular repair mechanisms. Errors are more likely to form when organisms are subjected to DNA damage by mutagenic compounds. 1-Nitropyrene, a nitrated polycyclic aromatic hydrocarbon (nitro-PAH), has been shown to be a potent mutagen that causes cancer. Nitro-PAHs can arise from diesel exhaust products in the environment. Out of all nitro-PAHs, 1-nitropyrene is found in largest quantities in the environment. This poses a great need to study its effects biochemically in order to address its toxicity in DNA. Other nitropyrene derivatives, including 1,6-dinitropyrene and 1,8-dinitropyrene, …

Toxoplasma Gondii Requires Its Plant-Like Heme Biosynthesis Pathway For Infection, Amy Bergmann, Kathleen Floyd, Melanie Key, Carly Dameron, Kerrick C. Rees, L. Brock Thornton, Daniel C. Whitehead, Iqbal Hamza, Zhicheng Dou

Publications

Heme, an iron-containing organic ring, is essential for virtually all living organisms by serving as a prosthetic group in proteins that function in diverse cellular activities ranging from diatomic gas transport and sensing, to mitochondrial respiration, to detoxification. Cellular heme levels in microbial pathogens can be a composite of endogenous de novo synthesis or exogenous uptake of heme or heme synthesis intermediates. Intracellular pathogenic microbes switch routes for heme supply when heme availability fluctuates in their replicative environment throughout infection. Here, we show that Toxoplasma gondii, an obligate intracellular human pathogen, encodes a functional heme biosynthesis pathway. A chloroplast-derived …

The Importance Of Ile716 Toward The Mutagenicity Of 8-Oxo-2’-Deoxyguanosine With Bacillus Fragment Dna Polymerase, Michelle L. Hamm, Anarosa A. Garcia, Rachel Gilbert, Manavi Johri, Miranda Ricart, Samantha L. Sholes, Laura A. Murray-Nerger, Eugene Y. Wu

Biology Faculty Publications

8-oxo-2’-deoxyguanosine (OdG) is a prominent DNA lesion that can direct the incorporation of dCTP or dATP during replication. As the latter reaction can lead to mutation, the ratio of dCTP/dATP incorporation can significantly affect the mutagenic potential of OdG. Previous work with the A-family polymerase BF and seven analogues of OdG identified a major groove amino acid, Ile716, which likely influences the dCTP/dATP incorporation ratio opposite OdG. To further probe the importance of this amino acid, dCTP and dATP incorporations opposite the same seven analogues were tested with two BF mutants, I716M and I716A. Results from these studies support the …

Therapeutic Drug Monitoring Of Apixaban Using Chromogenic Kits, Brooke Vogel

Undergraduate Honors Theses

Apixaban is a novel oral anticoagulant that prevents clotting by directly inhibiting Factor Xa in the coagulation cascade. Due to its different pharmacokinetics, previous standards for testing anticoagulant concentrations are ineffective at measuring apixaban. In this study, Hyphen Biomed Biophen Direct Xa Inhibitor and Biophen Heparin chromogenic kits from Aniara Diagnostica were used along with a NanoDrop™ One/One^C Microvolume UV-Vis Spectrophotometer to see if either of these kits provide acceptable precision and accuracy for the quantification of apixaban in plasma samples, as well as if there is a significant difference in these two kits at varying concentrations of apixaban. …

Reversible Inhibition Of Mycobacterial Dnab Protein Splicing By Zinc, Gabrielle Hardison

Honors College Theses

Inteins are emerging as post-translational regulatory elements, undergoing conditional protein splicing in response to a variety of environmental cues. Inteins are seamlessly removed by self-splicing from exteins, or flanking portions of the host protein, which they interrupt. DnaB of Mycobacterium smegmatis, a helicase essential for replication, harbors two inteins known as DnaBi1 and DnaBi2, each with discrete structural characteristics and insertion positions. DnaBi1 was used here to design a reporter system which links splicing with resistance to the antibiotic kanamycin. We built a construct that strictly requires catalytically active DnaBi1 for survival in the presence of kanamycin and used …

Rapid Evolution Of Starvation Resistance In Drosophila: Physiological And Molecular Mechanisms, Austin Joseph Mckenna

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Gibbs lab has maintained starvation-selected Drosophila melanogaster for >130 generations. These starvation-selected flies evolved an obese phenotype with a suite of physiological differences compared to control-fed flies. Previous studies have shown that long-term starvation-selected Drosophila contain more lipids, have lower metabolic rates and develop more slowly than controls. This dissertation encompasses 1) Examining the molecular mechanisms contributing to starvation resistance, 2) Functional validation of the candidate plin1 allele, and 3) Rapid physiological and genomic evolution in starvation-selected Drosophila.

Starvation-selected Drosophila survive starvation conditions much longer than control-fed flies. This study took a simple approach to identify possible differences in …

Novel Cyanoximates As An Alternative In Cancer Chemotherapy, Kafayat Aderonke Yusuf

Graduate Theses/Dissertations

Chemotherapy is one of the most effective treatment plans for several cancer types. The recurrent side effects derived from chemotherapy agents have warranted the search for novel chemical compounds with better efficacy and minimal side effects. In line with this idea, I investigated effects of a group of newly synthesized metal based chemical compounds called cyanoximates on HeLa human cancer cells. Cyanoximates used were Pt(DECO)₂, Pt(MCO)₂, and Pd(DECO)₂ along with the chemotherapy drug cisplatin as a positive control. I found that the metal cyanoximates reduced cell viability via apoptosis, and that Pt(DECO)₂ was most …

The Role Of Reactive Oxygen Species In The Gut Immune Response Of Cat Fleas (Ctenocephalides Felis), Clark Hall

Honors College Theses

Fleas transmit numerous deadly and debilitating diseases, including the causative agents of murine typhus and plague. Because initial entry of these infectious agents occurs while blood feeding, the immune response in the flea gut is considered to be the first line of defense against invading microbes. However, relatively few studies have identified the flea immune molecules that effectively resist or limit infection in the gut. In other hematophagous insects, an immediate immune response to imbibed pathogens is the generation of reactive oxygen species (ROS). In this study, we utilized cat fleas (Ctenocephalides felis) to investigate whether natural infections …

470— Quantifying The Shape Of A Plant (Brassica Rapa) During Growth Under Different Light Intensities Using Fractal Geometry, Matthew Cotroneo

GREAT Day Posters

Over time plants not only increase in size but also change their shape. Quantifying this change in shape, however, is challenging. Fractal dimension, a measure of how these plants fill space, can provide a wholistic understanding of plant shape and how that shape changes as the plants react to their environments. I used a high-resolution, three-dimensional scanner to estimate the shape of Brassica rapa plants during growth under three different light intensities: low (40 Einsteins), medium (75 Einsteins) and high (100 Einsteins). From these data, each plant's above-ground shape was quantified using fractal geometry. The fractal dimension (D) of plants …

Possible Roles For Essential Oils In Chemoprevention And Suppression Of Cancer, Chad Kirk Lillestolen

Senior Honors Theses

Cancer represents one of the costliest and most prevalent diseases to afflict the modern world, even though treatments have evolved steadily over the years and produce an increasingly positive outlook with each development and innovation. Essential oils have been used medicinally- among other purposes- for thousands of years and have begun to attract attention for possible applications to the field of oncology. Numerous investigations and publications have shed light on the possible chemopreventative (antioxidant and antimetastatic) uses of these oils, alongside cancer suppressive (apoptosis-inducing and cytotoxic) abilities that they may possess. With the high annual incidence of cancer and the …

Methylxanthines Inhibit Primary Amine Oxidase And Monoamine Oxidase Activities Of Human Adipose Tissue, Wiem Haj Ahmed, CéCile Peiro, Jessica Fontaine, Barry J. Ryan, Gemma K. Kinsella, Jeff O’Sullivan, Jean-Louis Grolleau, Gary T.M. Henehan, Christian CarpéNé

Articles

Abstract: Background: Methylxanthines including caffeine and theobromine are widely consumed compounds and were recently shown to interact with bovine copper-containing amine oxidase. To the best of our knowledge, no direct demonstration of any interplay between these phytochemicals and human primary amine oxidase (PrAO) has been reported to date. We took advantage of the coexistence of PrAO and monoamine oxidase (MAO) activities in human subcutaneous adipose tissue (hScAT) to test the interaction between several methylxanthines and these enzymes, which are involved in many key pathophysiological processes. Methods: Benzylamine, methylamine, and tyramine were used as substrates for PrAO and MAO in homogenates …

Understanding How Human Lipoxygenases Bind Molecular Oxygen And Arachidonic Acid Substrate, Austin Paul Primeaux

Honors Capstones

No abstract provided.

Optimization Of Methods For Cross-Species Infection Of Cell Cultures With Wolbachia, Sarah J. Lane

Honors Thesis

The common intracellular endosymbiont genus of bacteria called Wolbachia is of interest due to the promise it shows for playing a role in disease control. Wolbachia have a number of widely variable effects on its many species of host insects. In combination with these roles, Wolbachia largely affects reproduction and development of its host species. It can lead to feminization and cytoplasmic incompatibility (Werren et al. 2008). Furthermore, this species is vertically transmitted which means that it passes from mother to offspring (Caragata et al., 2016). In combination with its effects on reproduction, which can allow Wolbachia to propagate through …

The Organic Synthesis Of Anthranilic Acid Derivatives As Potential Active Antibiotics, Paul Chappell

Student Scholars Day Posters

The objective of this research project was to synthesize multiple derivatives of anthranilic acid. These derivatives will then be tested for antibiotic activity against Staphylococcus aureus and Escherichia coli (E. coli). As bacteria become more resistant to penicillin-based antibiotics, the exploration of anthranilic acid-based antibiotics could serve an important role for future medical use. This research project included data collection via 1H-NMR, 12C-NMR, TLC, MP, and IR to determine purity for biological testing.

C-Di-Gmp Modulates Type Iv Msha Pilus Retraction And Surface Attachment In Vibrio Cholerae, Kyle A. Floyd, Calvin K. Lee, Wujing Xian, Mahmoud Nametalla, Aneesa Valentine, Benjamin Crair, Shiwei Zhu, Hannah Q. Hughes, Jennifer L. Chlebek, Daniel C. Wu, Jin Hwan Park, Ali M. Farhat, Charles J. Lomba, Courtney K. Ellison, Yves V. Brun, Javier Campos-Gomez, Ankur B. Dalia, Jun Liu, Nicolas Biais, Gerard C. L. Wong, Fitnat H. Yildiz

Publications and Research

Biofilm formation by Vibrio cholerae facilitates environmental persistence, and hyperinfectivity within the host. Biofilm formation is regulated by 3’,5’-cyclic diguanylate (c-di-GMP) and requires production of the type IV mannose-sensitive hemagglutinin (MSHA) pilus. Here, we show that the MSHA pilus is a dynamic extendable and retractable system, and its activity is directly controlled by c-di-GMP. The interaction between c-di-GMP and the ATPase MshE promotes pilus extension, whereas low levels of c-di-GMP correlate with enhanced retrac- tion. Loss of retraction facilitated by the ATPase PilT increases near-surface roaming motility, and impairs initial surface attachment. However, prolonged retraction upon surface attach- ment results …

The Role Of Apkcs And Apkc Inhibitors In Cell Proliferation And Invasion In Breast And Ovarian Cancer, Tracess B. Smalley

USF Tampa Graduate Theses and Dissertations

Research has demonstrated that the atypical protein kinase C-zeta (PKC-ζ) is a component of many dysregulated pathways in breast and ovarian cancer, including cellular proliferation, survival, and cell cycle upregulation. Breast and ovarian cancers affect women every day and are second and fifth leading cause of cancer death. Women who seek treatments are commonly met with invasive surgeries or chemotherapy. Protein kinase C (PKC) is a family of serine and threonine phosphorylating kinases that have been shown to modulate and transduce signaling cascades that play roles in the development and survival of cancers. Atypical PKC (aPKC), have been heavily suggested …

Honeybees Fail To Discriminate Floral Scents In A Complex Learning Task After Consuming A Neonicotinoid Pesticide, Julie A. Mustard, Annie Gott, Jennifer Scott, Nancy L. Chavarria, Geraldine A. Wright

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

Neonicotinoids are pesticides used to protect crops but with known secondary influences at sublethal doses on bees. Honeybees use their sense of smell to identify the queen and nestmates, to signal danger and to distinguish flowers during foraging. Few behavioural studies to date have examined how neonicotinoid pesticides affect the ability of bees to distinguish odours. Here, we use a differential learning task to test how neonicotinoid exposure affects learning, memory, and olfactory perception in foraging-age honeybees. Bees fed with thiamethoxam could not perform differential learning and could not distinguish odours during short and long-term memory tests. Our data indicate …

Yeast Copper Proteins And Reactive Oxygen Species In Effecting Lifespan, Megan Bestwick

Post-Grant Reports

Mitochondria are essential organelles in most eukaryotic cells because of their role in metabolism and the production of ATP by the oxidative phosphorylation (OXPHOS) pathway, as well as other key cellular processes. Metal cofactors, such as copper (Cu) and iron (Fe), are incorporated into OXPHOS protein complexes of yeast located within the inner membrane of the mitochondria. Misincorporation or modulation of these available metals in mitochondrial enzymes leads to the production of reactive oxygen species (ROS). ROS are reactive molecules containing oxygen such as peroxides, superoxide, and hydroxyl radicals. Yeast are a good model for studying aging and the effect …

Parallel Quorum-Sensing System In Vibrio Cholerae Prevents Signal Interference Inside The Host., Samit Watve, Kelsey Barrasso, Sarah A Jung, Kristen J Davis, Lisa A Hawver, Atul Khataokar, Ryan G Palaganas, Matthew B Neiditch, Lark Perez, Wai-Leung Ng

College of Science & Mathematics Departmental Research

Many bacteria use quorum sensing (QS) to regulate virulence factor production in response to changes in population density. QS is mediated through the production, secretion, and detection of signaling molecules called autoinducers (AIs) to modulate population-wide behavioral changes. Four histidine kinases, LuxPQ, CqsS, CqsR and VpsS, have been identified in Vibrio cholerae as QS receptors to activate virulence gene expression at low cell density. Detection of AIs by these receptors leads to virulence gene repression at high cell density. The redundancy among these receptors is puzzling since any one of the four receptors is sufficient to support colonization of V. …

Trait Differentiation And Modular Toxin Expression In Palm-Pitvipers, Andrew J. Mason, Mark J. Margres, Jason L. Strickland, Darin R. Rokyta, Mahmood Sasa, Christopher L. Parkinson

Publications

Background

Modularity is the tendency for systems to organize into semi-independent units and can be a key to the evolution and diversification of complex biological systems. Snake venoms are highly variable modular systems that exhibit extreme diversification even across very short time scales. One well-studied venom phenotype dichotomy is a trade-off between neurotoxicity versus hemotoxicity that occurs through the high expression of a heterodimeric neurotoxic phospholipase A2 (PLA2) or snake venom metalloproteinases (SVMPs). We tested whether the variation in these venom phenotypes could occur via variation in regulatory sub-modules through comparative venom gland transcriptomics of representative Black-Speckled Palm-Pitvipers (Bothriechis …

Hur Ubiquitination By Brca1/Bard1 And Its Role In Controlling Gene Expression During Dna Damage Response, Gamage M. Aruggoda

Dissertations, Theses, and Capstone Projects

Despite our understanding of the biochemistry of the BRCA1/BARD1 E3 ligase, we know very little of the mechanism by which its cellular substrates, how they are chosen, how its E3 Ub ligase activity is regulated, which are the cofactors involved in this regulation, and how the substrates are modified during DDR. In this dissertation, I further evaluate BRCA1/BARD1-mediated E3 ligase activity and how CstF-50 and p97 regulate this reaction working as cofactors. My data show that BRCA1/BARD1 is an E3 ligase that ubiquitinates the RNA binding protein Human antigen R(HuR).

HuR is abundant in the nucleus and is transported to …

Through The Back Door: Proteins Escape Cells Without Conventional Permission, Michael J. Cohen

Dissertations, Theses, and Capstone Projects

Proteins secreted to the extracellular environment play a fundamental role as signals, in metabolism, and a variety of other processes. The process of secretion through the endoplasmic reticulum and Golgi to the plasma membrane is well documented, and all cargo in this pathway contains a signal peptide. However, a variety of proteins secreted from eukaryotes lack a signal peptide and are called unconventionally secreted proteins. Here we discuss known mechanisms of unconventional protein secretion, as well as model proteins which follow characterized pathways. Additionally, we summarize the roles various unconventionally secreted proteins play outside of cells and suggest criteria for …

Identification Of Uncommon Antibiotic-Producing Illinois Soil Isolates, Lesly Muniz, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on student sourcing antibiotic discovery from the soil. We researched tester strains B. subtilis and E. coli from the soil isolates obtained. We further verified if the isolates were common antibiotic bacteria. Unfortunately, this project heavily relied on biochemical tests, colony morphology, and Gram stains to reject or fail to reject our hypothesis. Our goal was to discover new antibiotic-producing bacteria that could be beneficial in combating ESKAPE strains. A proper PCR and DNA extraction would be required …

Putative Antibiotic Producer: A Pseudomonas Genus With Antibiotic Properties, John Tworek, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

There is a series antibiotic crisis in the world with catastrophic consequences if action is not take. Many diseases caused by bacteria are becoming untreatable because of the amount of pathogens resistant to the effect of antibiotics. The most prolific bacteria are the ESKAPE bacteria. They are nonsocomial pathogens that exhibit multi-drug resistance and virulence. My project will be working alongside the Tiny Earth Project (TEPI) to educate the public about the antibiotic crisis as well as obtaining a soil sample to possible discover new antibiotics. The DNA sequencing data retrieved from soil isolates against the two ESKAPE tester strains …

Screening For Antibiotic-Producers In Soil From A Garden, Long Tran, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

Multidrug-resistant pathogens are the leading cause of nosocomial infection, which killed more than 30,000 people in the United States every year. Among these, ESKAPE strains bugs, which comprise six highly drug-resistant bacteria, pose the greatest challenge to the healthcare system. In order to fight the antibiotic-resistant crises, novel antibiotic-producers must be discovered. This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on student sourcing antibiotic discovery from the soil. Pseudomonas was revealed to produce a zone of inhibition against Bacillus subtilis on LB media. The next step …

Pseudomonas And Bacillus Soil Isolates Produce Antibiotics, Chelsea Brandt, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

The recent emergence of antibiotic resistance bacterial strains presents a significant challenge and threat to human healthcare. While new methods of treatment such as bacteriophage therapy and combinations of existing antibiotics are being researched, the human population is in dire need of new antibiotics to replace those that are ineffective. This research addresses this need by identifying antibiotic producing bacteria in a soil sample from Davenport, IA. This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on studentsourcing antibiotic discovery from soil. Microbiology lab techniques and 16S …

Structure Of The Cell-Binding Component Of The Clostridium Difficile Binary Toxin Reveals A Di-Heptamer Macromolecular Assembly, Xingjian Xu, Raquel Godoy-Ruiz, Kaylin A. Adipietro, Christopher Peralta, Danya Ben-Hail, Kristeny M. Varney, Mary E. Cook, Braden M. Roth, Paul T. Wilder, Thomas Cleveland, Alexander Grishaev, Heather M. Neu, Sarah L. J. Michel, Wenbo Yu, Dorothy Beckett, Richard R. Rustand, Catherine Lancaster, John W. Loughney, Adam Kristopeit, Sianny Christantii, Jessica W. Olson, Alexander D. Mackerell, Amedee Des Georges, Edwin Pozharski, David J. Weber

Advanced Science Research Center

Targeting Clostridium difficile infection is challenging because treatment options are limited, and high recurrence rates are common. One reason for this is that hypervirulent C. difficile strains often have a binary toxin termed the C. difficile toxin, in addition to the enterotoxins TsdA and TsdB. The C. difficile toxin has an enzymatic component, termed CDTa, and a pore-forming or delivery subunit termed CDTb. CDTb was characterized here using a combination of singleparticle cryoelectron microscopy, X-ray crystallography, NMR, and other biophysical methods. In the absence of CDTa, 2 di-heptamer structures for activated CDTb (1.0 MDa) were solved at atomic resolution, including …

Analyzing The Effect On Ligand Sensitivity For Xenopus Tropicalis Mc1r, Mc3r, Mc4r, And Mc5r As A Result Of Coexpression With Gallus Gallus Mrap1 In Chinese Hamster Ovary Cells, Avery Niemann, Robert Dores

DU Undergraduate Research Journal Archive

Some melanocortin receptors and the accessory protein MRAP1 have been found to interact in novel ways when co-expressed in the same cells following stimulation with either ACTH (1-24) or αMSH. These interactions have been seen for mammalian, bird, and some bony fish melanocortin receptors. Such analysis has not been done yet on the amphibian melanocortin receptors, MC1R, MC3R, MC4R, and MC5R. To this end, this study was done on the effects regarding ligand sensitivity for ACTH (1-24) and αMSH, when the MC1R, MC3R, MC4R, and MC5R paralogs of the amphibian, Xenopus tropicalis were expressed in Chinese Hamster Ovary cells either …

An Evaluation Of Co-Culture Parameters Effecting Antibiotic Production In Soil Microbes, Rebecca Lindow

Master's Theses and Doctoral Dissertations

The rise of infections caused by antibiotic resistant bacteria, compounded by a reduction in antibiotic discovery and development, jeopardizes human health. Historically, antibiotics derive from secondary metabolites produced by soil microbes in pure culture, but recent genetic evidence suggests that microbes can produce more secondary metabolites than are currently observed. The modified crowded plate technique directly identifies antibiotic-producing soil microbes that were co-plated with a target pathogen. Here, this technique was refined by testing the effect of a D-alanine auxotrophic target pathogen rather than a prototrophic pathogen as well as investigating conditions most conducive to antibiotic production. Antibiotic producing conditions …