Biochemistry, Biophysics, and Structural Biology Commons^™

Structural Basis Of Amino Acid Surveillance By Higher-Order Trna-Mrna Interactions, Shuang Li, Zhaoming Su, Jean Lehmann, Vassiliki Stamatopoulou, Nikoleta Giarimoglou, Frances E Henderson, Lixin Fan, Grigore D Pintilie, Kaiming Zhang, Muyuan Chen, Steven J Ludtke, Yun-Xing Wang, Constantinos Stathopoulos, Wah Chiu, Jinwei Zhang

Faculty, Staff and Students Publications

Amino acid availability in Gram-positive bacteria is monitored by T-box riboswitches. T-boxes directly bind tRNAs, assess their aminoacylation state, and regulate the transcription or translation of downstream genes to maintain nutritional homeostasis. Here, we report cocrystal and cryo-EM structures of Geobacillus kaustophilus and Bacillus subtilis T-box-tRNA complexes, detailing their multivalent, exquisitely selective interactions. The T-box forms a U-shaped molecular vise that clamps the tRNA, captures its 3' end using an elaborate 'discriminator' structure, and interrogates its aminoacylation state using a steric filter fashioned from a wobble base pair. In the absence of aminoacylation, T-boxes clutch tRNAs and form a continuously …

Bipolar Fresh Osteochondral Allograft Transplantation And Joint Reconstruction For Patellar And Trochlear Cartilage Defects, Omid Jalali, Zachary Vredenburgh, John Prodromo, Neilen Benvegnu, George Frederick Rick Hatch

Faculty, Staff and Students Publications

Patellar instability is a debilitating condition, and trauma due to the dislocations may severely damage the articular cartilage of the patellofemoral joint. The lack of healing capacity of cartilage makes treatment of such lesions challenging. In young patients, preservation of native bone and cartilage is a priority, and therefore arthroplasty procedures should be avoided even in relatively larger lesions. Fresh osteochondral allografting has been described for these difficult and complex cases, with recent studies showing promising results. In this surgical technique, we describe the use of bipolar osteochondral allografts of the patella and trochlea and patellofemoral joint reconstruction for large …

Isotopic Characterization Of Nitrogen Oxides (NoX), Nitrous Acid (Hono), And Nitrate (PNo3-) From Laboratory Biomass Burning During Firex, Jiajue Chai, David J. Miller, Eric Scheuer, Jack Dibb, Vanessa Selimovic, Robert Yokelson, Kyle K. Zarzana, Steven Brown, Abigail R. Koss, Carsten Warneke, Meredith Hastings

Chemistry and Biochemistry Faculty Publications

New techniques have recently been developed and applied to capture reactive nitrogen species, including nitrogen oxides (NOx D NOCNO2), nitrous acid (HONO), nitric acid (HNO3), and particulate nitrate (pNO3 ), for accurate measurement of their isotopic composition. Here, we report – for the first time – the isotopic composition of HONO from biomass burning (BB) emissions collected during the Fire Influence on Regional to Global Environments Experiment (FIREX, later evolved into FIREX-AQ) at the Missoula Fire Science Laboratory in the fall of 2016. We used our newly developed annular denuder system (ADS), which was verified to completely capture HONO associated …

Autophagy Protein Nrbf2 Has Reduced Expression In Alzheimer's Brains And Modulates Memory And Amyloid-Beta Homeostasis In Mice, Veronik Lachance, Qian Wang, Eric Sweet, Insup Choi, Cui-Zan Cai, Xu-Xu Zhuang, Jessica Li Jiang, Robert D. Blitzer, Ozlem Bozdagi-Gunal, Bin Zhang, Jia-Hong Lu, Zhenyu Yue

Biology Faculty Publications

Background Dysfunctional autophagy is implicated in Alzheimer's Disease (AD) pathogenesis. The alterations in the expression of many autophagy related genes (ATGs) have been reported in AD brains; however, the disparity of the changes confounds the role of autophagy in AD. Methods To further understand the autophagy alteration in AD brains, we analyzed transcriptomic (RNAseq) datasets of several brain regions (BA10, BA22, BA36 and BA44 in 223 patients compared to 59 healthy controls) and measured the expression of 130 ATGs. We used autophagy-deficient mouse models to assess the impact of the identified ATGs depletion on memory, autophagic activity and amyloid-beta (A …

High Concentrations Of Trimethylamines In Slime Glands Inhibit Skein Unraveling In Pacific Hagfish, Gaurav Jain, Marie Starksen, Kashika Singh, Christopher Hoang, Paul Yancey, Charlene Mccord, Douglas S. Fudge

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Hagfish defend themselves from fish predators by producing large volumes of gill-clogging slime when they are attacked. The slime consists of seawater and two major components that are ejected from the slime glands: mucus and threads. The threads are produced within specialized cells and packaged into intricately coiled bundles called skeins. Skeins are kept from unraveling via a protein adhesive that dissolves when the skeins are ejected from the slime glands. Previous work revealed that hagfish slime glands have high concentrations of methylamines including trimethylamine N-oxide (TMAO), trimethylglycine (betaine) and dimethylglycine (DMG); however, the function of these compounds in the …

Case 67: Phenylalanine Hydroxylase: An Investigation Of Its Structure Leads To The Development Of Pku New Therapies, Dr. Kathleen Cornely

Chemistry & Biochemistry Case Studies

The characteristics of phenylalanine hydroxylase, the enzyme missing in persons afflicted with the genetic disorder phenylketonuria (PKU), are examined. Understanding how the enzyme works will allow the development of drugs to treat this condition.

Defining The Layers Of A Sensory Cilium With Storm And Cryoelectron Nanoscopy, Michael A Robichaux, Valencia L Potter, Zhixian Zhang, Feng He, Jun Liu, Michael F Schmid, Theodore G Wensel

Faculty, Staff and Students Publications

Primary cilia carry out numerous signaling and sensory functions, and defects in them, "ciliopathies," cause a range of symptoms, including blindness. Understanding of their nanometer-scale ciliary substructures and their disruptions in ciliopathies has been hindered by limitations of conventional microscopic techniques. We have combined cryoelectron tomography, enhanced by subtomogram averaging, with superresolution stochastic optical reconstruction microscopy (STORM) to define subdomains within the light-sensing rod sensory cilium of mouse retinas and reveal previously unknown substructures formed by resident proteins. Domains are demarcated by structural features such as the axoneme and its connections to the ciliary membrane, and are correlated with molecular …

Constituent Partitioning Consensus Docking Models And Application In Drug Discovery, Rainer Metcalf

USF Tampa Graduate Theses and Dissertations

This work expounds on some of the current computational tools and programs available and the best practices associated with their use. A high-level introduction, intended for both novices and the semi-experienced, focusing on the more common programs used in scientific literature is the scope of this topic. Both classical and quantum techniques are described. Classical methodologies include Molecular Dynamics, Monte Carlo, energy minimization methods, molecular docking, low-mode, and homology modeling. Quantum chemistry techniques are also discussed encompassing Hartree-Fock, Post-Hartree-Fock theories, and Density Functional Theory along with associated basis sets.

Along with established methodologies, novel theoretical methods are introduced for furthering …

Stability Of Petal Color Polymorphism: The Significance Of Anthocyanin Accumulation In Photosynthetic Tissues, José Carlos Del Valle, Cristina Alcalde-Eon, Mª Teresa Escribano-Bailón, Mª Luisa Buide, Justen B. Whittall, Eduardo Narbona

Biology

Background: Anthocyanins are the primary source of colour in flowers and also accumulate in vegetative tissues, where they have multiple protective roles traditionally attributed to early compounds of the metabolic pathway (flavonols, flavones, etc.). Petal-specific loss of anthocyanins in petals allows plants to escape from the negative pleiotropic effects of flavonoid and anthocyanins loss in vegetative organs, where they perform a plethora of essential functions. Herein, we investigate the degree of pleiotropy at the biochemical scale in a pink-white flower colour polymorphism in the shore campion, Silene littorea. We report the frequencies of pink and white individuals across 21 populations …

Amyloid Protein Aggregation And Associated Toxicity, Chamani A. Niyangoda

USF Tampa Graduate Theses and Dissertations

Amyloidosis is a group of diseases in which amyloid fibrils accumulate and deposit into plaques and intracellular inclusions which lead to disruption of the tissue architecture and function. Most of the amyloid diseases are incurable due to a lack of understanding of the amyloid formation, as well as associated toxicity. My research work is focused on three different aspects of amyloid aggregation.

The aim of the first project is to investigate the potential use of deep-blue autofluorescence (dbAF) as an intrinsic optical probe to study amyloid self-assembly. This novel fluorescence signal is excited at the long wavelength edge of the …

The Role Of Atypical Protein Kinase C In Colorectal Cancer Cells Carcinogenesis, S M Anisul Islam

USF Tampa Graduate Theses and Dissertations

Colorectal cancer (CRC) is the third most common malignancy and the fourth most common cause of cancer-related death worldwide. CRC is a life-threatening disease due to therapy-resistant cancerous cells. The exact mechanisms of cell growth, survival, metastasis and inter & intracellular signaling pathways involved in CRC are still a significant challenge. Moreover, the treatment of metastatic CRC considered palliative for many years aimed for an improved life, with little hope of a cure, highlighting the need for developing novel targeted therapy for CRC. Hence, investigating new molecular mechanism(s) that lead to colorectal carcinogenesis may give insight into the therapeutic target. …

Comparison Of Montage With Conventional Stereoscopic Seven‑Field Photographs For Assessment Of Etdrs Diabetic Retinopathy Severity, Nam V. Nguyen, Erin M. Vigil, Muhammad Hassan, Muhammad S. Halim, Sean C. Baluyot, Hugo A. Guzman, Rubbia Afridi, Diana V. Do, Yasir J. Sepah

Department of Biochemistry: Faculty Publications

Background: The ETDRS stereoscopic seven-field (7F) has been a standard imaging and grading protocol for assessment of diabetic retinopathy (DR) severity score in many clinical trials. To the best of our knowledge, the comparison between montage and stereoscopic 7F has not been reported in the literature. Therefore, the main purpose of this study is to compare agreement between montage and stereoscopic seven-field (7F) photographs in the assessment of DR severity.

Methods: Stereoscopic 7F photographs were captured from subjects with DR. Montages of monoscopic 7F images were created using Adobe Photoshop CS6 Extended©. The best quality image of each stereo pair …

The Role Of Secreted Proteases In Regulating Disease Progression In Staphylococcus Aureus, Brittney D. Gimza

USF Tampa Graduate Theses and Dissertations

Staphylococcus aureus is a highly successful pathogen capable of producing a wealth of virulence factors in the human host. Of note, ten extracellular proteases are produced alongside these virulence factors and play a multifaceted role during infection. They not only cleave host proteins to promote bacterial invasion, immune evasion and survival, but also control disease progression by modulating the stability of self-derived pathogenic determinants. The importance of the secreted proteases modulating virulence factor stability is evidenced by our groups previous finding that a protease-null strain has a substantially increased infectious capacity in a murine model of sepsis; resulting from the …

A Novel Cytokine Response Modulatory Function Of Mek Inhibitors Mediates Therapeutic Efficacy, Mengyu Xie

USF Tampa Graduate Theses and Dissertations

Despite the recent success of immune-checkpoint blockade therapy for late-stage non-small cell lung cancer (NSCLC), lung cancer is still the leading cause of cancer deaths worldwide. One of the most important characteristics of lung cancer in therapeutic decision-making are the targetable molecules, including EGFR, ALK, BRAF, and MEK. The excitement of immune-checkpoint blockade therapy has triggered concerted efforts that focus on exploring combinations of immune checkpoint therapy with other approved therapeutic regimens aiming at further augmenting positive outcomes and survival. However, the lack of understanding of underlying mechanisms and evidence-based clinical testing has hindered the progress to a cure. Hence, …

Aerial And Ground-Based Optical Gas Imaging Survey Of Uinta Basin Oil And Gas Wells, Seth N. Lyman, Trang Tran, Marc L. Mansfield, Arvind P. Ravikumar

Bingham Research Center

We deployed a helicopter with an infrared optical gas imaging camera to detect hydrocarbon emissions from 3,428 oil and gas facilities (including 3,225 producing oil and gas well pads) in Utah’s Uinta Basin during winter and spring 2018. We also surveyed 419 of the same well pads from the ground. Winter conditions led to poor contrast between emission plumes and the ground, leading to a detection limit for the aerial survey that was between two and six times worse than a previous summertime survey. Because the ground survey was able to use the camera’s high-sensitivity mode, the rate of detected …

Targeting Bacterial Resistance And Cancer Metastasis: A Structure Based Approach, Kyle Galen Kroeck

USF Tampa Graduate Theses and Dissertations

Current research in pharmaceutical development commonly utilizes a profusion of methods in molecular modeling in order to probe intricate biological problems. Many original and promising compounds have been identified and developed by integrating experimental and computational methods. Structural biology utilizes many different research techniques including x-ray crystallography, NMR, and electron microscopy in order to develop molecular models of macromolecules that are of biological interest. Such techniques can be used in conjunction with molecular docking, which utilizes those molecular models in order to target macromolecules of therapeutic interest by computationally analyzing the conformations adopted by ligands upon interaction with a desired …

Clpc Affects The Intracellular Survival Capacity Of Staphylococcus Aureus In Non-Professional Phagocytic Cells, Gubesh Gunaratnam, Lorena Tuchscherr, Mohamed I. Elhawy, Ralph Bertram, Janina Eisenbeis, Christian Spengler, Thomas Tschernig, Bettina Löffler, Greg A. Somerville, Karin Jacobs, Mathias Herrmann, Markus Bischoff

School of Veterinary and Biomedical Sciences: Faculty Publications

Invasion and persistence of bacteria within host cells requires that they adapt to life in an intracellular environment. This adaptation induces bacterial stress through events such as phagocytosis and enhanced nutrient-restriction. During stress, bacteria synthesize a family of proteins known as heat shock proteins (HSPs) to facilitate adaptation and survival. Previously, we determined the Staphylococcus aureus HSP ClpC temporally alters bacterial metabolism and persistence. This led us to hypothesize that ClpC might alter intracellular survival. Inactivation of clpC in S. aureus strain DSM20231 significantly enhanced long-term intracellular survival in human epithelial (HaCaT) and endothelial (EA.hy926) cell lines, without markedly affecting …

Altered Proteasome Expression And Nuclear Factor (Erythroid-Derived 2)-Like Signaling In Experimental Autoimmune Encephalomyelitis, Kara Leasure Shanley

Biomedical Sciences ETDs

Multiple sclerosis (MS) is a complex neurological disorder characterized by the interactions between heightened inflammation, oxidative stress and neurodegeneration. We and others have previously demonstrated that proteasome dysfunction and its consequences are also important factors in the pathology of both MS and its rodent model, experimental autoimmune encephalomyelitis (EAE). While proteasome subunit alterations in EAE have been observed, the underlying mechanisms are poorly understood. The first goal of this dissertation was to characterize the mechanisms that regulate proteasome expression and composition in neural cells in EAE and in vitro.

Immunohistochemical analysis of the EAE spinal cord shows changes in …

The Total Syntheses Of Jbir-94 And Two Synthetic Analogs And Their Cytotoxicities Against A549 (Ccl-185) Human Small Lung Cancer Cells, Cathy L. Mangum, Mica B. Munford, Alyssa Sam, Sandra K. Young, Jeremy T. Beales, Yagya Prasad Subedi, Chad D. Mangum, Tanner J. Allen, Miranda S. Liddell, Andrew I. Merrell, Diana I. Saavedra, Becky L. Williams, Nicole Evans, Joseph L. Beales, Mike A. Christiansen

Chemistry and Biochemistry Faculty Publications

We here disclose the total syntheses of the natural polyphenol JBIR-94 and two nonnatural analogs, whose structures are of interest for their bioactivity potential as radical scavengers. Although we initially attempted this by dually acylating both of putrecine’s amine nitrogens in a single pot, our endeavors with this method (which has been successfully reported by other groups) proved ineffectual. We accordingly opted for the lengthier approach of acylating each amine individually, which gratuitously prevailed and also aligns with separate literature precedent. Moreover, we here share our analysis of these target compounds’ cytotoxicities and IC₅₀ values against A549 (CCL-185) human …

An Investigation Into The Heterogeneity Of Insect Arylalkylamine N-Acyltransferases, Brian G. O'Flynn

USF Tampa Graduate Theses and Dissertations

Arylalkylamine N-acyltransferases (AANATs) have in recent years been suggested as potential new insecticide targets. These promiscuous enzymes are involved in the N-acylation of biogenic amines to form N-acylamides. Mammalian AANAT is predominantly associated with circadian rhythm regulation, as it catalyzes the formation of N-acetylserotonin, the precursor of melatonin, from serotonin. In insects, this process is a key step in melanism, as well as hardening of the cuticle, removal of biogenic amines, and in the biosynthesis of fatty acid amides. The unique nature of each insect AANAT (iAANAT) isoform characterized indicates that while catalyzing similar reactions, each insect accommodates …