Biochemistry Commons^™

Regenerative Therapy By Replacement Of Stem Cells In Females, Saara Ahmad, Rehana Rehman, Fatima Ahmad

Department of Biological & Biomedical Sciences

No abstract provided.

Association Of Vitamin D Deficiency And Vdbp Gene Polymorphism With The Risk Of Ami In A Pakistani Population, Mujtaba Mubashir, Shaheena Anwar, Asal Khan Tareen, Naseema Mehboobali, Khalida Iqbal, Mohammad Iqbal

Department of Biological & Biomedical Sciences

OBJECTIVE: To investigate the relationship of vitamin D deficiency and risk of AMI in a Pakistani population, and to find out any associationbetween vitamin D binding protein (VDBP) genotypes and risk of AMI in this population.
METHODS: In a comparative cross-sectional study, 246 patients (age: 20-70 years; 171 males and 75 females) with first AMI were enrolled with informed consent. Similarly, 345 healthy adults (230 males and 115 females) were enrolled as controls. Their fasting serum samples were analyzed for 25 (OH) vitamin D, lipids and other biomarkers using kit methods, while DNA was analyzed for VDBP genotypes using PCR-RFLP …

Mitochondrial Reactive Oxygen Species In Lipotoxic Hearts Induces Post-Translational Modifications Of Akap121, Drp1 And Opa1 That Promote Mitochondrial Fission, Kensuke Tsushima, Heiko Bugger, Adam R. Wende, Jamie Soto, Gregory A. Jenson, Austin R. Tor, Rose Mcglauflin, Helena C. Kenny, Yuan Zhang, Rhonda Souvenir, Xiao X. Hu, Crystal L. Sloan, Renata O. Pereira, Vitor A. Lira, Kenneth W. Spitzer, Terry L. Sharp, Kooresh I. Shoghi, Genevieve C. Sparagna, Eva A. Rog-Zielinska, Peter Kohl, Oleh Khalimonchuk, Jean E. Schaffer, E. Dale Abel

Department of Biochemistry: Faculty Publications

Rationale: Cardiac lipotoxicity, characterized by increased uptake, oxidation and accumulation of lipid intermediates, contributes to cardiac dysfunction in obesity and diabetes. However, mechanisms linking lipid overload and mitochondrial dysfunction are incompletely understood.

Objective: To elucidate the mechanisms for mitochondrial adaptations to lipid overload in postnatal hearts in vivo.

Methods and Results: Using a transgenic mouse model of cardiac lipotoxicity overexpressing long-chain acyl-CoA synthetase 1 in cardiomyocytes, we show that modestly increased myocardial fatty acid uptake leads to mitochondrial structural remodeling with significant reduction in minimum diameter. This is associated with increased palmitoyl-carnitine oxidation and increased reactive oxygen species (ROS) generation …

Association Of Vitamin D Binding Protein Polymorphism With Risk Of Type 2 Diabetes Mellitus In A Pakistani Urban Population: A Case Control Study, Khalida Iqbal, Najmul Islam, Iqbal Azam, Ali Asghar, Naseema Mehboobali, Mohammad Perwaiz Iqbal

Department of Biological & Biomedical Sciences

Objective: To assess if genotypes/diplotypes of vitamin D binding protein have any association with type 2 diabetes mellitus.
Methods: This case-control study was conducted from January 2013 to July 2015 at the endocrinology clinics of the Aga Khan University Hospital, Karachi, and comprised adult patients with type 2 diabetes and their age- and gender-matched healthy controls. Venous blood was obtained and assessed for serum/plasma 25 hydroxyvitamin D, parathyroid hormone, calcium, alkaline phosphatase and creatinine. Deoxyribonucleic acid was isolated and genotyping was done by polymerase chain reaction-restriction fragment length polymorphismprocedures.
Results: Of the 330 participants, there were 165(50%) …

High-Throughput Single-Molecule Telomere Characterization, Jennifer Mccaffrey, Eleanor Young, Katy Lassahn, Justin Sibert, Steven Pastor, Harold Riethman, Ming Xiao

School of Medical Diagnostics & Translational Sciences Publications

We have developed a novel method that enables global subtelomere and haplotype-resolved analysis of telomere lengths at the single-molecule level. An in vitro CRISPR/Cas9 RNA-directed nickase system directs the specific labeling of human (TTAGGG) n DNA tracts in genomes that have also been barcoded using a separate nickase enzyme that recognizes a 7bp motif genome-wide. High-throughput imaging and analysis of large DNA single molecules from genomes labeled in this fashion using a nanochannel array system permits mapping through subtelomere repeat element (SRE) regions to unique chromosomal DNA while simultaneously measuring the (TTAGGG) n tract length at the end of each …

Using Competition Assays To Quantitatively Model Cooperative Binding By Transcription Factors And Other Ligands., Jacob Peacock, James B Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

BACKGROUND: The affinities of DNA binding proteins for target sites can be used to model the regulation of gene expression. These proteins can bind to DNA cooperatively, strongly impacting their affinity and specificity. However, current methods for measuring cooperativity do not provide the means to accurately predict binding behavior over a wide range of concentrations.

METHODS: We use standard computational and mathematical methods, and develop novel methods as described in Results.

RESULTS: We explore some complexities of cooperative binding, and develop an improved method for relating in vitro measurements to in vivo function, based on ternary complex formation. We derive …

Redox-Active Nanomaterials For Nanomedicine Applications, C. M. Sims, S. K. Hanna, D. A. Heller, C. P. Horoszko, M. E. Johnson, A. R. Montoro Bustos, V. Reipa, Kathryn R. Riley, B. C. Nelson

Chemistry & Biochemistry Faculty Works

Nanomedicine utilizes the remarkable properties of nanomaterials for the diagnosis, treatment, and prevention of disease. Many of these nanomaterials have been shown to have robust antioxidative properties, potentially functioning as strong scavengers of reactive oxygen species. Conversely, several nanomaterials have also been shown to promote the generation of reactive oxygen species, which may precipitate the onset of oxidative stress, a state that is thought to contribute to the development of a variety of adverse conditions. As such, the impacts of nanomaterials on biological entities are often associated with and influenced by their specific redox properties. In this review, we overview …

Kinetic Characterization Of Listeria Monocytogenes 2-C- Methyl-D-Erythritol 4-Phosphate Cytidylyltransferase ( Cms ) Enzymes Using High Performance Liquid Chromatography ( Hplc ), Mark Oblazny

Theses and Dissertations

Infectious diseases, with increasing prevalence of antibiotic resistant bacteria, coupled with the declining rate in discovery of antimicrobial agents, impose one of the most significant threats to human health. Here we identify 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase (CMS) as a valid target for antibiotic development which is an enzyme in pathogenic organisms that leads to the biosynthesis of isoprene precursor molecules. Isoprene molecules are one of nature’s most common building blocks that are vital to many biological metabolic processes and are synthesized via the mevalonic acid dependent (MVA), or methylerythritol phosphate (MEP) pathway. Vertebrates utilize the MVA pathway, while many pathogenic bacteria …

The Biochemical Assessment Of Two Secreted Acid Phosphatases From Leishmania Tarentolae, Their Response To Electric Fields, Glycosidase Incubation, And / Or Vanadium, Benjamin M. Dorsey

Theses and Dissertations

Leishmaniasis, as defined by the Center for Disease Control and Prevention, is a neglected tropical disease with 1.6 million new cases reported each year. However, there is yet to be safe, effective, and affordable treatments provided to those affected by this disease1. Still underappreciated as a potential pharmaceutical targets, especially for cutaneous leishmaniasis infections, are the two isozymes of secreted acid phosphatase (SAP); secreted acid phosphatase 1 (SAP1) and secreted acid phosphatase 2 (SAP2). These enzymes are involved in the survival of the parasite in the sand fly vector, and the prevention of host macrophages from forming parasitophorous vacuole and …

Prebiotic Rna Network Formation: A Taxonomy Of Molecular Cooperation, Cole Mathis, Sanjay N. Ramprasad, Sara Imari Walker, Niles Lehman

Chemistry Faculty Publications and Presentations

Cooperation is essential for evolution of biological complexity. Recent work has shown game theoretic arguments, commonly used to model biological cooperation, can also illuminate the dynamics of chemical systems. Here we investigate the types of cooperation possible in a real RNA system based on the Azoarcusribozyme, by constructing a taxonomy of possible cooperative groups. We construct a computational model of this system to investigate the features of the real system promoting cooperation. We find triplet interactions among genotypes are intrinsically biased towards cooperation due to the particular distribution of catalytic rate constants measured empirically in the real system. For other …

Functional Characteristics And Genomic Sequencing Of Antarctic Environmental Isolates, Amanda Kemper, Christina Aigner, Michelle Tigges, Sara Anderson

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

2-D Electrophoresis Modeling Of Multienzyme Cutting Of Polypeptides, Howard Mayes

Theses

2-Dimensional Electrophoresis is one of the tools in the identification of proteins by molecular weight and pH. The display of molecular weight allows the researcher to quickly identify whether a specific protein or peptide string is in the sample. The pH measurement allows even better resolution between different species in the sample. The MultiEnzyme ElectroPhoresis (MEEP) program tries to model that by providing a graph that displays separated protein strings by both molecular weight and pH. The ability to cleave the protein with 43 different enzyme variations allows the researcher to analyze appropriate enzymes to isolate a protein subsequence before …

First-Principles And Model Simulation Of All-Optical Spin Reversal, Thomas George, G.P. Zhang, Z. Babyak, Y. Xue, Y. Bai

Chemistry & Biochemistry Faculty Works

All-optical spin switching is a potential trailblazer for information storage and communication at an unprecedented fast rate free of magnetic fields. However, the current wisdom is largely based on semiempirical models of effective magnetic fields and heat pulses, so it is difficult to provide high-speed design protocols for actual devices. Here, we carry out a massively parallel first-principles and model calculation for 13 spin systems and magnetic layers, free of any effective field, to establish a simpler and alternative paradigm of laser-induced ultrafast spin reversal and to point out a path to a full-integrated photospintronic device. It is the interplay …

1H, 15N, And 13C Chemical Shift Assignments Of The Regulatory Domain Of Human Calcineurin, Dinesh K. Yadav, Sri Ramya Tata, John Hunt, Erik C. Cook, Trevor P. Creamer, Nicholas C. Fitzkee

Center for Structural Biology Faculty Publications

Calcineurin (CaN) plays an important role in T-cell activation, cardiac system development and nervous system function. Previous studies have demonstrated that the regulatory domain (RD) of CaN binds calmodulin (CaM) towards the N-terminal end. Calcium-loaded CaM activates the serine/threonine phosphatase activity of CaN by binding to the RD, although the mechanistic details of this interaction remain unclear. It is thought that CaM binding at the RD displaces the auto-inhibitory domain (AID) from the active site of CaN, activating phosphatase activity. In the absence of calcium-loaded CaM, the RD is disordered, and binding of CaM induces folding in the RD. In …

Activation Of The Phospholipid Scramblase Tmem16f By Nanosecond Pulsed Electric Field (Nspef) Facilitates Its Diverse Cytophysiological Effects, Claudia Muratori, Andrei G. Pakhomov, Elena Gianulis, Jade Meads, Maura Casciola, Peter A. Mollica, Olga N. Pakhomova

Bioelectrics Publications

Nanosecond pulsed electric fields (nsPEF) are emerging as a novel modality for cell stimulation and tissue ablation. However, the downstream protein effectors responsible for nsPEF bioeffects remain to be established. Here we demonstrate that nsPEF activate TMEM16F (or Anoctamin 6), a protein functioning as a Ca²⁺-dependent phospholipid scramblase and Ca²⁺-activated chloride channel. Using confocal microscopy and patch clamp recordings, we investigated the relevance of TMEM16F activation for several bioeffects triggered by nsPEF, including phosphatidylserine (PS) externalization, nanopore-conducted currents, membrane blebbing, and cell death. In HEK 293 cells treated with a single 300-ns pulse of 25.5 kV/cm, …

Photosensing And Thermosensing By Phytochrome B Require Both Proximal And Distal Allosteric Features Within The Dimeric Photoreceptor, E Sethe Burgie, Adam N. Bussell, Shu-Hui Lye, Tong Wang, Weiming Hu, Katrice E. Mcloughlin, Erin L. Weber, Huilin Li, Richard D. Vierstra

Biology Faculty Research

Phytochromes (Phys) encompass a diverse collection of bilin-containing photoreceptors that help plants and microorganisms perceive light through photointerconversion between red light (Pr) and far-red light (Pfr)-absorbing states. In addition, Pfr reverts thermally back to Pr via a highly enthalpic process that enables temperature sensation in plants and possibly other organisms. Through domain analysis of the Arabidopsis PhyB isoform assembled recombinantly, coupled with measurements of solution size, photoconversion, and thermal reversion, we identified both proximal and distal features that influence all three metrics. Included are the downstream C-terminal histidine kinase-related domain known to promote dimerization and a conserved patch just upstream …

Ydj1 Governs Fungal Morphogenesis And Stress Response, And Facilitates Mitochondrial Protein Import Via Mas1 And Mas2, Jinglin L. Xie, Iryna Bohovych, Erin O.Y. Wong, Jean-Philippe Lambert, Anne-Claude Gingras, Oleh Khalimonchuk, Leah E. Cowen, Michelle D. Leach

Department of Biochemistry: Faculty Publications

Mitochondria underpin metabolism, bioenergetics, signalling, development and cell death in eukaryotes. Most of the ~1,000 yeast mitochondrial proteins are encoded in the nucleus and synthesised as precursors in the cytosol, with mitochondrial import facilitated by molecular chaperones. Here, we focus on the Hsp40 chaperone Ydj1 in the fungal pathogen Candida albicans, finding that it is localised to both the cytosol and outer mitochondrial membrane, and is required for cellular stress responses and for filamentation, a key virulence trait. Mapping the Ydj1 protein interaction network highlighted connections with co-chaperones and regulators of filamentation. Furthermore, the mitochondrial processing peptidases Mas1 and …

Pharmacological Antagonism And The Olfactory Code, Mihwa Na

Dissertations, Theses, and Capstone Projects

Mammals can detect and discriminate uncountable odors through their odorant receptors. To accommodate the countless and diverse odors, exceptionally large numbers of odorant receptor (OR) genes are expressed in mammals. In addition, the mammals utilize a combinatorial code, where an odorant molecule can activate multiple ORs; an OR also responds to a set of multiple odorants. In nature, an odor is often a complex mixture of multiple odorant molecules. The combination of the ORs activated by each constituent generates the unique olfactory code for the particular odor.

Some odorants can antagonize select ORs, as discussed in Chapter 1. An antagonist …

Regulation Of The Amyloid Precursor Protein By Prostaglandin J2, A Mediator Of Inflammation: Relevance To Alzheimer’S Disease, Teneka L. Jean-Louis

Dissertations, Theses, and Capstone Projects

Inflammation plays a major role in Alzheimer’s disease (AD). Investigating how specific mediators of inflammation contribute to neurodegeneration in AD is crucial. Our studies focused on cyclooxygenases, which are key enzymes in inflammation and highly relevant to AD. Cyclooxygenases (COX -1, constitutive; COX-2, inducible) have emerged as important determinants of AD pathogenesis and progression. COX-2 is highly induced in AD, correlating with AD severity, and COX-1 is also involved in AD. Cyclooxygenases are the rate-limiting enzymes that convert arachidonic acid into prostaglandins (PGs), the principal mediators of CNS neuroinflammation.

The overall GOAL of these studies was to address the mechanisms …

Identification Of Potential Tissue-Specific Cancer Biomarkers And Development Of Cancer Versus Normal Genomic Classifiers, Akram Mohammed, Greyson Biegert, Jiri Adamec, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Machine learning techniques for cancer prediction and biomarker discovery can hasten cancer detection and significantly improve prognosis. Recent “OMICS” studies which include a variety of cancer and normal tissue samples along with machine learning approaches have the potential to further accelerate such discovery. To demonstrate this potential, 2,175 gene expression samples from nine tissue types were obtained to identify gene sets whose expression is characteristic of each cancer class. Using random forests classification and ten-fold cross-validation, we developed nine single-tissue classifiers, two multi-tissue cancer-versus-normal classifiers, and one multi-tissue normal classifier. Given a sample of a specified tissue type, the single-tissue …