Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

University of Kentucky

Discipline
Keyword
Publication Year
Publication
Publication Type

Articles 391 - 420 of 654

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Inhibition Of Mammalian Glycoprotein Ykl-40 Identification Of The Physiological Ligand, Abhishek A. Kognole, Christina M. Payne Jan 2017

Inhibition Of Mammalian Glycoprotein Ykl-40 Identification Of The Physiological Ligand, Abhishek A. Kognole, Christina M. Payne

Chemical and Materials Engineering Faculty Publications

YKL-40 is a mammalian glycoprotein associated with progression, severity, and prognosis of chronic inflammatory diseases and a multitude of cancers. Despite this well documented association, identification of the lectin′s physiological ligand and, accordingly, biological function has proven experimentally difficult. YKL-40 has been shown to bind chito-oligosaccharides; however, the production of chitin by the human body has not yet been documented. Possible alternative ligands include proteoglycans, polysaccharides, and fibers like collagen, all of which makeup the extracellular matrix. It is likely that YKL-40 is interacting with these alternative polysaccharides or proteins within the body, extending its function to cell biological roles …


Progesterone Receptor And Prostaglandins Mediate Luteinizing Hormone-Induced Changes In Messenger Rnas For Adamts Proteases In Theca Cells Of Bovine Periovulatory Follicles, Erin L. Willis, Phillip J. Bridges, Joanne E. Fortune Jan 2017

Progesterone Receptor And Prostaglandins Mediate Luteinizing Hormone-Induced Changes In Messenger Rnas For Adamts Proteases In Theca Cells Of Bovine Periovulatory Follicles, Erin L. Willis, Phillip J. Bridges, Joanne E. Fortune

Animal and Food Sciences Faculty Publications

Little is known about the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of extracellular proteases in ovarian follicles of non‐rodent species, particularly in theca cells. In the present study, temporal changes in the abundance of mRNA encoding four ADAMTS subtypes and hormonal regulation of mRNA encoding two subtypes were investigated in theca interna cells during the periovulatory period in cattle. Gonadotropin‐releasing hormone (GnRH) was injected into animals to induce a luteinizing hormone (LH)/follicle‐stimulating hormone (FSH) surge, and follicles were obtained at 0 hr post‐GnRH (preovulatory) or at 6, 12, 18, or 24 hr (periovulatory). ADAMTS1, ‐2, …


Investigation Of The Mechanism Of Action For Mithramycin And The Biosynthesis Of L-Rednose In Saquayamycins, Stevi Weidenbach Jan 2017

Investigation Of The Mechanism Of Action For Mithramycin And The Biosynthesis Of L-Rednose In Saquayamycins, Stevi Weidenbach

Theses and Dissertations--Pharmacy

Natural products continue to be a major chemical lead matter for drug discovery due to their diverse chemical structures and bioactivities. Clinically significant natural products include anti-cancer and anti-infective compounds and while many more of these compounds show promising bioactivity, their clinical relevance is often limited by toxicity or poor solubility. Combinatorial biosynthesis can be employed to modify existing chemical scaffolds towards reducing these limitations. To fully take advantage of these biochemical tools, it is important to understand the biosynthesis and mechanism of action of the molecules.

Saccharides in glycosylated natural products provide specific interactions with cellular targets and are …


Evolution Of Equine Arteritis Virus During Persistent Infection In The Reproductive Tract Of The Stallion And The Male Donkey, Bora Nam Jan 2017

Evolution Of Equine Arteritis Virus During Persistent Infection In The Reproductive Tract Of The Stallion And The Male Donkey, Bora Nam

Theses and Dissertations--Veterinary Science

Equine arteritis virus (EAV) establishes persistent infection in the stallion reproductive tract, and the carrier stallion continues to shed virus in semen for weeks to years or lifelong. The objective of this study was to elucidate the intra-host evolution of EAV during persistent infection in stallions. Seven EAV seronegative stallions were experimentally infected with EAV KY84 strain and followed for 726 days post-infection, and sequential clinical samples including semen were collected for virus isolation and next-generation sequencing (NGS). In addition, archived sequential semen samples from two stallions that were naturally infected with EAV KY84 for a long-period (up to 10 …


Toward Biochemical Conversion Of Lignocellulose On-Farm: Pretreatment And Hydrolysis Of Corn Stover In Situ, Alicia A. Modenbach, Sue E. Nokes, Michael D. Montross, Barbara L. Knutson Jan 2017

Toward Biochemical Conversion Of Lignocellulose On-Farm: Pretreatment And Hydrolysis Of Corn Stover In Situ, Alicia A. Modenbach, Sue E. Nokes, Michael D. Montross, Barbara L. Knutson

Biosystems and Agricultural Engineering Faculty Publications

High-solids lignocellulosic pretreatment using NaOH followed by high-solids enzymatic hydrolysis was evaluated for an on-farm biochemical conversion process. Increasing the solids loadings for these processes has the potential for increasing glucose concentrations and downstream ethanol production; however, sequential processing at high-solids loading similar to an on-farm cellulose conversion system has not been studied. This research quantified the effects of high-solids pretreatment with NaOH and subsequent high-solids enzymatic hydrolysis on cellulose conversion. As expected, conversion efficiency was reduced; however, the highest glucose concentration (40.2 g L-1), and therefore the highest potential ethanol concentration, resulted from the high-solids combined pretreatment …


Sex Differences In The Subjective Effects Of Oral Δ9-Thc In Cannabis Users, Jessica S. Fogel, Thomas H. Kelly, Philip M. Westgate, Joshua A. Lile Jan 2017

Sex Differences In The Subjective Effects Of Oral Δ9-Thc In Cannabis Users, Jessica S. Fogel, Thomas H. Kelly, Philip M. Westgate, Joshua A. Lile

Behavioral Science Faculty Publications

Previous studies suggest that there are sex differences in endocannabinoid function and the response to exogenous cannabinoids, though data from clinical studies comparing acute cannabinoid effects in men and women under controlled laboratory conditions are limited. To further explore these potential differences, data from 30 cannabis users (N=18 M, 12 F) who completed previous Δ9-tetrahydrocannabinol (Δ9-THC) discrimination studies were combined for this retrospective analysis. In each study, subjects learned to discriminate between oral Δ9-THC and placebo and then received a range of Δ9-THC doses (0, 5, 15 and a “high” dose of …


Metabolic Reprogramming Of Human Lung Cancer Cells And Ex Vivo Tissues Revealed By Uhr-Ftms Analysis Of Small Amino And Carboxyl Metabolites, Ye Yang Jan 2017

Metabolic Reprogramming Of Human Lung Cancer Cells And Ex Vivo Tissues Revealed By Uhr-Ftms Analysis Of Small Amino And Carboxyl Metabolites, Ye Yang

Theses and Dissertations--Toxicology and Cancer Biology

Studies were carried out to understand how human lung cancer cells and human ex vivo lung cancer tissues that are metabolically reprogramed compared with analogous non-cancer cells or non-cancer tissues. A Stable isotope resolved metabolomics (SIRM) approach was used to fulfill this aim by employing 13C, 2H or 15N labeled metabolic precursors like 13C6-Glc, 13C2-Gly, 2H2-Gly, 2H3-Ser, 13C5, 15N2-Gln to trace the flow of the labeled atoms into the down stream metabolic network. NMR and mass spectrometry are two …


The Role Of Alternative Polyadenylation Mediated By Cpsf30 In Arabidopsis Thaliana, Guijie Hao Jan 2017

The Role Of Alternative Polyadenylation Mediated By Cpsf30 In Arabidopsis Thaliana, Guijie Hao

Theses and Dissertations--Plant and Soil Sciences

Drought stress is considered one of the most devastating abiotic stress factors that limit crop productivity for modern agriculture worldwide. There is a large range of physiological and biochemical responses induced by drought stress. The responses range from physiological and biochemical to regulation at transcription and posttranscriptional levels. Post-transcription, the products encoded by eukaryotic genes must undergo a series of modifications to become a mature mRNA. Polyadenylation is an important one in terms of regulation. Polyadenylation impacts gene expression through determining the coding and regulation potential of the mRNA, especially when different mRNAs from the same gene may be polyadenylated …


Rad Gtpase: Identification Of Novel Regulatory Mechanisms And A New Function In Modulation Of Bone Density And Marrow Adiposity, Catherine Nicole Kaminski Withers Jan 2017

Rad Gtpase: Identification Of Novel Regulatory Mechanisms And A New Function In Modulation Of Bone Density And Marrow Adiposity, Catherine Nicole Kaminski Withers

Theses and Dissertations--Molecular and Cellular Biochemistry

The small GTP-binding protein Rad (RRAD, Ras associated with diabetes) is the founding member of the RGK (Rad, Rem, Rem2, and Gem/Kir) family that regulates voltage-dependent calcium channel function. Given its expression in both excitable and non-excitable cell types, the control mechanisms for Rad regulation and the potential for novel functions for Rad beyond calcium channel modulation are open questions. Here we report a novel interaction between Rad and Enigma, a scaffolding protein that also binds to the E3 ubiquitin ligase Smad ubiquitin regulatory factor 1 (Smurf1). Overexpression of Smurf1, but not …


Viral Fusion Protein Tm-Tm Interactions: Modulators Of Protein Function And Potential Antiviral Targets, Stacy Webb Jan 2017

Viral Fusion Protein Tm-Tm Interactions: Modulators Of Protein Function And Potential Antiviral Targets, Stacy Webb

Theses and Dissertations--Molecular and Cellular Biochemistry

Enveloped viruses, such as HIV, influenza, and Ebola, utilize surface glycoproteins to bind and fuse with a target cell membrane. This fusion event is necessary for release of viral genomic material so the virus can ultimately reproduce and spread. The recently emerged Hendra virus (HeV) is a negative-sense, single-stranded RNA paramyxovirus that presents a considerable threat to human health as there are currently no human vaccines or antivirals available. The HeV utilizes two surface glycoproteins, the fusion protein (F) and the attachment protein (G), to drive membrane fusion. Through this process, the F protein undergoes an irreversible conformational change, transitioning …


Platelet Endocytosis: Roles In Hemostasis And Innate Immunity, Meenakshi Banerjee Jan 2017

Platelet Endocytosis: Roles In Hemostasis And Innate Immunity, Meenakshi Banerjee

Theses and Dissertations--Molecular and Cellular Biochemistry

Endocytosis is key to fibrinogen (Fg) uptake, receptor trafficking of integrins (αIIbβ3, αvβ3) and purinergic receptors (P2Y1, P2Y12), and thereby for normal platelet function. However, platelet endocytosis could potentially be critical for actively sensing changes in vascular micro-environments and responding accordingly to what is being taken up. This is a more dynamic view of platelets as active surveyors of the vasculature; extending the importance of platelet endocytosis beyond granule biogenesis and perhaps even hemostasis. The mechanistic underpinnings of endocytosis, its importance in platelets, and the molecular machinery required …


Investigation Of The Physiological Role Of Rin Gtpase In Cell Death, Axonal Injury, And Inflammation Following Traumatic Brain Injury, Megan Pannell Jan 2017

Investigation Of The Physiological Role Of Rin Gtpase In Cell Death, Axonal Injury, And Inflammation Following Traumatic Brain Injury, Megan Pannell

Theses and Dissertations--Molecular and Cellular Biochemistry

Traumatic brain injury (TBI) is a progressive disorder, in which the primary injury results in the initiation of a complex cascade of secondary biochemical and metabolic changes resulting in lasting neurological dysfunction and cognitive impairment. The heterogeneous nature of the disease has complicated the development of pharmacological agents to improve the outcomes of TBI; to date, no therapeutic treatment has been shown to be effective in clinical trials. Treatments targeting multiple secondary outcomes (cell death, axonal degeneration, and inflammation) may provide enhanced therapeutic efficacy following TBI.

Small Ras family GTP-binding proteins govern diverse cellular processes by directing the relay of …


Transcriptomic Analyses Of Cathatranthus Roseus Hairy Roots Overexpressing Crmyc2 And Orca3 And Roles Of Cross-Family Transcription Factor Interaction In Terpenoid Indole Alkaloid Biosynthesis, Xueyi Sui Jan 2017

Transcriptomic Analyses Of Cathatranthus Roseus Hairy Roots Overexpressing Crmyc2 And Orca3 And Roles Of Cross-Family Transcription Factor Interaction In Terpenoid Indole Alkaloid Biosynthesis, Xueyi Sui

Theses and Dissertations--Plant and Soil Sciences

Catharanthus roseus (Madagascar periwinkle), is a well-known medicinal plant that produces a vast array of terpenoid indole alkaloids (TIAs), including two anticancer compounds vinblastine and vincristine. Industrial scale production of TIAs is hampered by the difficulties of total chemical synthesis of these compounds and the fragmented knowledge on TIA pathway. Transcriptional regulation of the TIA biosynthetic pathway has not been thoroughly investigated in Catharanthus and only a few structural genes have been identified as the targets of two master regulators: the basic helix-loop-helix (bHLH) transcription factor (TF) CrMYC2 and APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF), ORCA3. Next generation sequencing (NGS) has been …


Comparative Proteomic Analyses Of The Parietal Lobe From Rhesus Monkeys Fed A High-Fat/Sugar Diet With And Without Resveratrol Supplementation, Relative To A Healthy Diet: Insights Into The Roles Of Unhealthy Diets And Resveratrol On Function, Aaron M. Swomley, Judy C. Triplett, Jeriel T. Keeney, Govind Warrier, Kevin J. Pearson, Julie A. Mattison, Rafael De Cabo, Jian Cai, Jon B. Klein, D. Allan Butterfield Jan 2017

Comparative Proteomic Analyses Of The Parietal Lobe From Rhesus Monkeys Fed A High-Fat/Sugar Diet With And Without Resveratrol Supplementation, Relative To A Healthy Diet: Insights Into The Roles Of Unhealthy Diets And Resveratrol On Function, Aaron M. Swomley, Judy C. Triplett, Jeriel T. Keeney, Govind Warrier, Kevin J. Pearson, Julie A. Mattison, Rafael De Cabo, Jian Cai, Jon B. Klein, D. Allan Butterfield

Chemistry Faculty Publications

A diet consisting of a high intake of saturated fat and refined sugars is characteristic of a Western-diet and has been shown to have a substantial negative effect on human health. Expression proteomics were used to investigate changes to the parietal lobe proteome of rhesus monkeys consuming either a high fat and sugar (HFS) diet, a HFS diet supplemented with resveratrol (HFS+RSV), or a healthy control diet for 2 years. Here we discuss the modifications in the levels of 12 specific proteins involved in various cellular systems including metabolism, neurotransmission, structural integrity, and general cellular signaling following a nutritional intervention. …


The Role Of Gln146 To The Stability And Activity Of Manganese Superoxide Dismutase, Ting Wang Jan 2017

The Role Of Gln146 To The Stability And Activity Of Manganese Superoxide Dismutase, Ting Wang

Theses and Dissertations--Chemistry

Gln146 is a highly conserved outer-sphere amino acid residue at the active site of MnSOD. It serves as a hydrogen bond donor to both the solvent molecules at the active site and Tyr 34, the conserved “gateway” amino acid residue. This dissertation develops our understanding of the effect of amino acid Gln146 at the second shell of the active site of metalloprotein MnSOD in facilitating metal binding, the modulation of redox potential, and the optimization of catalytic activity and structure stability. Different from the wild-type MnSOD, Q146E is always purified as a completely apo-protein with zero active metal ion and …


Illuminate The Pathway Of Membrane Protein Association And Degradation, Zhaoshuai Wang Jan 2017

Illuminate The Pathway Of Membrane Protein Association And Degradation, Zhaoshuai Wang

Theses and Dissertations--Chemistry

Escherichia coli transporter protein AcrB and its homologues are the inner membrane components of the Resistance-Nodulation-Division (RND) family efflux pumps in Gram-negative bacteria. It is well accepted that soluble proteins are only marginally stable, but such insight is missing for membrane proteins. The lack of stability data, including thermodynamic stability and oligomer association affinity is a result of intrinsic difficulties in working with membrane proteins. In addition, the degradation of soluble proteins in E. coli has been extensively studied whereas the degradation process of membrane proteins remains unclear. A focus of my thesis is the validation and development of methods …


Synthesis And Development Of Zwitterionic Pei (Zpei) For Optimized Delivery Of Nucleic Acids, Joseph Raleigh Duke Iii Jan 2017

Synthesis And Development Of Zwitterionic Pei (Zpei) For Optimized Delivery Of Nucleic Acids, Joseph Raleigh Duke Iii

Theses and Dissertations--Chemistry

Gene therapy holds promise for the treatment a wide range of diseases ranging from cystic fibrosis to cardiovascular disease to cancer. The need for safe and efficient gene delivery methods remains the primary barrier to human gene therapy. Non-viral vector materials, including polymers, can be designed to be biocompatible and non-immunogenic, but lack the efficiency to be clinically relevant. Gene therapy awaits the development of new materials that are both safe and efficient. Here, we have synthesized a series of modified zwitterionic polymers based on the common transfecting agent polyethylenimine (PEI). Using a variety of biochemical and biophysical methods we …


Rit1 Gtpase Regulates Sox2 Transcriptional Activity And Hippocampal Neurogenesis, Sajad Mir, Weikang Cai, Douglas A. Andres Dec 2016

Rit1 Gtpase Regulates Sox2 Transcriptional Activity And Hippocampal Neurogenesis, Sajad Mir, Weikang Cai, Douglas A. Andres

Molecular and Cellular Biochemistry Faculty Publications

Adult neurogenesis, the process of generating mature neurons from neuronal progenitor cells, makes critical contributions to neural circuitry and brain function in both healthy and disease states. Neurogenesis is a highly regulated process in which diverse environmental and physiological stimuli are relayed to resident neural stem cell populations to control the transcription of genes involved in self-renewal and differentiation. Understanding the molecular mechanisms governing neurogenesis is necessary for the development of translational strategies to harness this process for neuronal repair. Here we report that the Ras-related GTPase RIT1 serves to control the sequential proliferation and differentiation of adult hippocampal neural …


Respective Contributions Of Single And Compound Granule Fusion To Secretion By Activated Platelets, Anita Eckly, Jean-Yves Rinckel, Fabienne Proamer, Neslihan Ulas, Smita Joshi, Sidney W. Whiteheart, Christian Gachet Nov 2016

Respective Contributions Of Single And Compound Granule Fusion To Secretion By Activated Platelets, Anita Eckly, Jean-Yves Rinckel, Fabienne Proamer, Neslihan Ulas, Smita Joshi, Sidney W. Whiteheart, Christian Gachet

Molecular and Cellular Biochemistry Faculty Publications

Although granule secretion is pivotal in many platelet responses, the fusion routes of α and δ granule release remain uncertain. We used a 3D reconstruction approach based on electron microscopy to visualize the spatial organization of granules in unstimulated and activated platelets. Two modes of exocytosis were identified: a single mode that leads to release of the contents of individual granules and a compound mode that leads to the formation of granule-to-granule fusion, resulting in the formation of large multigranular compartments. Both modes occur during the course of platelet secretion. Single fusion events are more visible at lower levels of …


The Nuts And Bolts Of The Platelet Release Reaction, Smita Joshi, Sidney W. Whiteheart Nov 2016

The Nuts And Bolts Of The Platelet Release Reaction, Smita Joshi, Sidney W. Whiteheart

Molecular and Cellular Biochemistry Faculty Publications

Secretion is essential to many of the roles that platelets play in the vasculature, e.g., thrombosis, angiogenesis, and inflammation, enabling platelets to modulate the microenvironment at sites of vascular lesions with a myriad of bioactive molecules stored in their granules. Past studies demonstrate that granule cargo release is mediated by Soluble NSF Attachment Protein Receptor (SNARE) proteins, which are required for granule-plasma membrane fusion. Several SNARE regulators, which control when, where, and how the SNAREs interact, have been identified in platelets. Additionally, platelet SNAREs are controlled by post-translational modifications, e.g., phosphorylation and acylation. Although there have been many …


P70s6k1 (S6k1)-Mediated Phosphorylation Regulates Phosphatidylinositol 4-Phosphate 5-Kinase Type I Γ Degradation And Cell Invasion, Naser Jafari, Qiaodan Zheng, Liqing Li, Wei Li, Lei Qi, Jianyong Xiao, Tianyan Gao, Cai Huang Oct 2016

P70s6k1 (S6k1)-Mediated Phosphorylation Regulates Phosphatidylinositol 4-Phosphate 5-Kinase Type I Γ Degradation And Cell Invasion, Naser Jafari, Qiaodan Zheng, Liqing Li, Wei Li, Lei Qi, Jianyong Xiao, Tianyan Gao, Cai Huang

Markey Cancer Center Faculty Publications

Phosphatidylinositol 4-phosphate 5-kinase type I γ (PIPKIγ90) ubiquitination and subsequent degradation regulate focal adhesion assembly, cell migration, and invasion. However, it is unknown how upstream signals control PIPKIγ90 ubiquitination or degradation. Here we show that p70S6K1 (S6K1), a downstream target of mechanistic target of rapamycin (mTOR), phosphorylates PIPKIγ90 at Thr-553 and Ser-555 and that S6K1-mediated PIPKIγ90 phosphorylation is essential for cell migration and invasion. Moreover, PIPKIγ90 phosphorylation is required for the development of focal adhesions and invadopodia, key machineries for cell migration and invasion. Surprisingly, substitution of Thr-553 and Ser-555 …


Pleckstrin Homology (Ph) Domain Leucine-Rich Repeat Protein Phosphatase Controls Cell Polarity By Negatively Regulating The Activity Of Atypical Protein Kinase C, Xiaopeng Xiong, Xin Li, Yang-An Wen, Tianyan Gao Oct 2016

Pleckstrin Homology (Ph) Domain Leucine-Rich Repeat Protein Phosphatase Controls Cell Polarity By Negatively Regulating The Activity Of Atypical Protein Kinase C, Xiaopeng Xiong, Xin Li, Yang-An Wen, Tianyan Gao

Markey Cancer Center Faculty Publications

The proper establishment of epithelial polarity allows cells to sense and respond to signals that arise from the microenvironment in a spatiotemporally controlled manner. Atypical PKCs (aPKCs) are implicated as key regulators of epithelial polarity. However, the molecular mechanism underlying the negative regulation of aPKCs remains largely unknown. In this study, we demonstrated that PH domain leucine-rich repeat protein phosphatase (PHLPP), a novel family of Ser/Thr protein phosphatases, plays an important role in regulating epithelial polarity by controlling the phosphorylation of both aPKC isoforms. Altered expression of PHLPP1 or PHLPP2 disrupted polarization of Caco2 cells grown in 3D cell cultures …


Mycosins Are Required For The Stabilization Of The Esx-1 And Esx-5 Type Vii Secretion Membrane Complexes, Vincent J. C. Van Winden, Roy Ummels, Sander R. Piersma, Connie R. Jiménez, Konstantin V. Korotkov, Wilbert Bitter, Edith N. G. Houben Oct 2016

Mycosins Are Required For The Stabilization Of The Esx-1 And Esx-5 Type Vii Secretion Membrane Complexes, Vincent J. C. Van Winden, Roy Ummels, Sander R. Piersma, Connie R. Jiménez, Konstantin V. Korotkov, Wilbert Bitter, Edith N. G. Houben

Molecular and Cellular Biochemistry Faculty Publications

ABSTRACT Pathogenic mycobacteria contain up to five type VII secretion (T7S) systems, ESX-1 to ESX-5. One of the conserved T7S components is the serine protease mycosin (MycP). Strikingly, whereas MycP is essential for secretion, the protease activity of MycP1 in Mycobacterium tuberculosis has been shown to be dispensable for secretion. The essential role of MycP therefore remains unclear. Here we show that MycP1 and MycP5 of M. marinum have similar phenotypes, confirming that MycP has a second unknown function that is essential for its T7S system. To investigate whether this role is related to proper functioning of …


Spyb, A Small Heme-Binding Protein, Affects The Composition Of The Cell Wall In Streptococcus Pyogenes, Rebecca J. Edgar, Jing Chen, Sashi Kant, Elena Rechkina, Jeffrey S. Rush, Lennart S. Forsberg, Bernhard Jaehrig, Parastoo Azadi, Veronika Tchesnokova, Evgeni V. Sokurenko, Haining Zhu, Konstantin V. Korotkov, Vijay Pancholi, Natalia Korotkova Oct 2016

Spyb, A Small Heme-Binding Protein, Affects The Composition Of The Cell Wall In Streptococcus Pyogenes, Rebecca J. Edgar, Jing Chen, Sashi Kant, Elena Rechkina, Jeffrey S. Rush, Lennart S. Forsberg, Bernhard Jaehrig, Parastoo Azadi, Veronika Tchesnokova, Evgeni V. Sokurenko, Haining Zhu, Konstantin V. Korotkov, Vijay Pancholi, Natalia Korotkova

Molecular and Cellular Biochemistry Faculty Publications

Streptococcus pyogenes (Group A Streptococcus or GAS) is a hemolytic human pathogen associated with a wide variety of infections ranging from minor skin and throat infections to life-threatening invasive diseases. The cell wall of GAS consists of peptidoglycan sacculus decorated with a carbohydrate comprising a polyrhamnose backbone with immunodominant N-acetylglucosamine side-chains. All GAS genomes contain the spyBA operon, which encodes a 35-amino-acid membrane protein SpyB, and a membrane-bound C3-like ADP-ribosyltransferase SpyA. In this study, we addressed the function of SpyB in GAS. Phenotypic analysis of a spyB deletion mutant revealed increased bacterial aggregation, and reduced sensitivity to β-lactams of the …


Inhibition Of Human Metapneumovirus Binding To Heparan Sulfate Blocks Infection In Human Lung Cells And Airway Tissues, Edita M. Klimyte, Stacy E. Smith, Pasqua Oreste, David Lembo, Rebecca Ellis Dutch Oct 2016

Inhibition Of Human Metapneumovirus Binding To Heparan Sulfate Blocks Infection In Human Lung Cells And Airway Tissues, Edita M. Klimyte, Stacy E. Smith, Pasqua Oreste, David Lembo, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Human metapneumovirus (HMPV), a recently discovered paramyxovirus, infects nearly 100% of the world population and causes severe respiratory disease in infants, the elderly, and immunocompromised patients. We previously showed that HMPV binds heparan sulfate proteoglycans (HSPGs) and that HMPV binding requires only the viral fusion (F) protein. To characterize the features of this interaction critical for HMPV binding and the role of this interaction in infection in relevant models, we utilized sulfated polysaccharides, heparan sulfate mimetics, and occluding compounds. Iota-carrageenan demonstrated potent anti-HMPV activity by inhibiting binding to lung cells mediated by the F protein. Furthermore, analysis of a minilibrary …


An Arginine Finger Regulates The Sequential Action Of Asymmetrical Hexameric Atpase In The Double-Stranded Dna Translocation Motor, Zhengyi Zhao, Gian Marco De-Donatis, Chad T. Schwartz, Huaming Fang, Jingyuan Li, Peixuan Guo Oct 2016

An Arginine Finger Regulates The Sequential Action Of Asymmetrical Hexameric Atpase In The Double-Stranded Dna Translocation Motor, Zhengyi Zhao, Gian Marco De-Donatis, Chad T. Schwartz, Huaming Fang, Jingyuan Li, Peixuan Guo

Pharmaceutical Sciences Faculty Publications

Biological motors are ubiquitous in living systems. Currently, how the motor components coordinate the unidirectional motion is elusive in most cases. Here, we report that the sequential action of the ATPase ring in the DNA packaging motor of bacteriophage ϕ29 is regulated by an arginine finger that extends from one ATPase subunit to the adjacent unit to promote noncovalent dimer formation. Mutation of the arginine finger resulted in the interruption of ATPase oligomerization, ATP binding/hydrolysis, and DNA translocation. Dimer formation reappeared when arginine mutants were mixed with other ATPase subunits that can offer the arginine to promote their interaction. Ultracentrifugation …


Human Metapneumovirus Induces Reorganization Of The Actin Cytoskeleton For Direct Cell-To-Cell Spread, Farah El Najjar, Nicolás Cifuentes-Muñoz, Jing Chen, Haining Zhu, Ursula J. Buchholz, Carole L. Moncman, Rebecca Ellis Dutch Sep 2016

Human Metapneumovirus Induces Reorganization Of The Actin Cytoskeleton For Direct Cell-To-Cell Spread, Farah El Najjar, Nicolás Cifuentes-Muñoz, Jing Chen, Haining Zhu, Ursula J. Buchholz, Carole L. Moncman, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Paramyxovirus spread generally involves assembly of individual viral particles which then infect target cells. We show that infection of human bronchial airway cells with human metapneumovirus (HMPV), a recently identified paramyxovirus which causes significant respiratory disease, results in formation of intercellular extensions and extensive networks of branched cell-associated filaments. Formation of these structures is dependent on actin, but not microtubule, polymerization. Interestingly, using a co-culture assay we show that conditions which block regular infection by HMPV particles, including addition of neutralizing antibodies or removal of cell surface heparan sulfate, did not prevent viral spread from infected to new target cells. …


Comparative Analysis Of Linker Histone H1, Mecp2, And Hmgd1 On Nucleosome Stability And Target Site Accessibility, Caitlyn Riedmann, Yvonne N. Fondufe-Mittendorf Sep 2016

Comparative Analysis Of Linker Histone H1, Mecp2, And Hmgd1 On Nucleosome Stability And Target Site Accessibility, Caitlyn Riedmann, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Chromatin architectural proteins (CAPs) bind the entry/exit DNA of nucleosomes and linker DNA to form higher order chromatin structures with distinct transcriptional outcomes. How CAPs mediate nucleosome dynamics is not well understood. We hypothesize that CAPs regulate DNA target site accessibility through alteration of the rate of spontaneous dissociation of DNA from nucleosomes. We investigated the effects of histone H1, high mobility group D1 (HMGD1), and methyl CpG binding protein 2 (MeCP2), on the biophysical properties of nucleosomes and chromatin. We show that MeCP2, like the repressive histone H1, traps the nucleosome in a more compact mononucleosome structure. Furthermore, histone …


Lipophosphoglycans From Leishmania Amazonensis Strains Display Immunomodulatory Properties Via Tlr4 And Do Not Affect Sand Fly Infection, Paula M. Nogueira, Rafael R. Assis, Ana C. Torrecilhas, Elvira M. Saraiva, Natália L. Pessoa, Marco A. Campos, Eric F. Marialva, Cláudia M. Ríos-Velasquez, Felipe A. Pessoa, Nágila F. Secundino, Jerônimo N. Rugani, Elsa Nieves, Salvatore J. Turco, Maria N. Melo, Rodrigo P. Soares Aug 2016

Lipophosphoglycans From Leishmania Amazonensis Strains Display Immunomodulatory Properties Via Tlr4 And Do Not Affect Sand Fly Infection, Paula M. Nogueira, Rafael R. Assis, Ana C. Torrecilhas, Elvira M. Saraiva, Natália L. Pessoa, Marco A. Campos, Eric F. Marialva, Cláudia M. Ríos-Velasquez, Felipe A. Pessoa, Nágila F. Secundino, Jerônimo N. Rugani, Elsa Nieves, Salvatore J. Turco, Maria N. Melo, Rodrigo P. Soares

Molecular and Cellular Biochemistry Faculty Publications

The immunomodulatory properties of lipophosphoglycans (LPG) from New World species of Leishmania have been assessed in Leishmania infantum and Leishmania braziliensis, the causative agents of visceral and cutaneous leishmaniasis, respectively. This glycoconjugate is highly polymorphic among species with variation in sugars that branch off the conserved Gal(β1,4)Man(α1)-PO4 backbone of repeat units. Here, the immunomodulatory activity of LPGs from Leishmania amazonensis, the causative agent of diffuse cutaneous leishmaniasis, was evaluated in two strains from Brazil. One strain (PH8) was originally isolated from the sand fly and the other (Josefa) was isolated from a human case. The ability of …


Als Mutant Sod1 Interacts With G3bp1 And Affects Stress Granule Dynamics, Jozsef Gal, Lisha Kuang, Kelly R. Barnett, Brian Z. Zhu, Susannah C. Shissler, Konstantin V. Korotkov, Lawrence J. Hayward, Edward J. Kasarskis, Haining Zhu Aug 2016

Als Mutant Sod1 Interacts With G3bp1 And Affects Stress Granule Dynamics, Jozsef Gal, Lisha Kuang, Kelly R. Barnett, Brian Z. Zhu, Susannah C. Shissler, Konstantin V. Korotkov, Lawrence J. Hayward, Edward J. Kasarskis, Haining Zhu

Molecular and Cellular Biochemistry Faculty Publications

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Mutations in Cu/Zn superoxide dismutase (SOD1) are responsible for approximately 20 % of the familial ALS cases. ALS-causing SOD1 mutants display a gain-of-toxicity phenotype, but the nature of this toxicity is still not fully understood. The Ras GTPase-activating protein-binding protein G3BP1 plays a critical role in stress granule dynamics. Alterations in the dynamics of stress granules have been reported in several other forms of ALS unrelated to SOD1. To our surprise, the mutant G93A SOD1 transgenic mice exhibited pathological cytoplasmic inclusions that co-localized with G3BP1-positive granules in spinal cord motor neurons. …