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Articles 121 - 150 of 264

Full-Text Articles in Amino Acids, Peptides, and Proteins

Syk Inhibitors In Clinical Development For Hematological Malignancies, Delong Liu, Aleksandra Mamorska-Dyga Jul 2017

Syk Inhibitors In Clinical Development For Hematological Malignancies, Delong Liu, Aleksandra Mamorska-Dyga

NYMC Faculty Publications

Spleen tyrosine kinase (Syk) is a cytosolic non-receptor protein tyrosine kinase (PTK) and is mainly expressed in hematopoietic cells. Syk was recognized as a critical element in the B-cell receptor signaling pathway. Syk is also a key component in signal transduction from other immune receptors like Fc receptors and adhesion receptors. Several oral Syk inhibitors including fostamatinib (R788), entospletinib (GS-9973), cerdulatinib (PRT062070), and TAK-659 are being assessed in clinical trials. The second generation compound, entospletinib, showed promising results in clinical trials against B-cell malignancies, mainly chronic lymphoid leukemia. Syk inhibitors are being evaluated in combination regimens in multiple malignancies.

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Chloroformate Derivatization For Tracing The Fate Of Amino Acids In Cells And Tissues By Multiple Stable Isotope Resolved Metabolomics (Msirm), Ye Yang, Teresa W. -M. Fan, Andrew N. Lane, Richard M. Higashi Jul 2017

Chloroformate Derivatization For Tracing The Fate Of Amino Acids In Cells And Tissues By Multiple Stable Isotope Resolved Metabolomics (Msirm), Ye Yang, Teresa W. -M. Fan, Andrew N. Lane, Richard M. Higashi

Center for Environmental and Systems Biochemistry Faculty Publications

Amino acids have crucial roles in central metabolism, both anabolic and catabolic. To elucidate these roles, steady-state concentrations of amino acids alone are insufficient, as each amino acid participates in multiple pathways and functions in a complex network, which can also be compartmentalized. Stable Isotope-Resolved Metabolomics (SIRM) is an approach that uses atom-resolved tracking of metabolites through biochemical transformations in cells, tissues, or whole organisms. Using different elemental stable isotopes to label multiple metabolite precursors makes it possible to resolve simultaneously the utilization of these precursors in a single experiment. Conversely, a single precursor labeled with two (or more) different …

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Quaternary Interactions And Supercoiling Modulate The Cooperative Dna Binding Of Agt, Manana Melikishvili, Michael G. Fried Jul 2017

Quaternary Interactions And Supercoiling Modulate The Cooperative Dna Binding Of Agt, Manana Melikishvili, Michael G. Fried

Center for Structural Biology Faculty Publications

Human O6-alkylguanine-DNA alkyltransferase (AGT) repairs mutagenic O6-alkylguanine and O4-alkylthymine adducts in single-stranded and duplex DNAs. The search for these lesions, through a vast excess of competing, unmodified genomic DNA, is a mechanistic challenge that may limit the repair rate in vivo. Here, we examine influences of DNA secondary structure and twist on protein–protein interactions in cooperative AGT complexes formed on lesion-free DNAs that model the unmodified parts of the genome. We used a new approach to resolve nearest neighbor (nn) and long-range (lr) components from the ensemble-average cooperativity, ωave. We found …

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B7h6: A Cancer Biomarker For The Development Of Novel Immunotherapy Approaches, Mariana Phillips May 2017

B7h6: A Cancer Biomarker For The Development Of Novel Immunotherapy Approaches, Mariana Phillips

Seton Hall University Dissertations and Theses (ETDs)

Cancer-based immunotherapy has led the evolution of biologics that can stimulate immune responses towards tumor eradication. The synthesis of small to intermediate size molecules with the targeting and effector functions of mAb may represent a novel class of immunotherapeutics that may overcome the limitations of their biological counterparts.Towards this objective, B7H6 has been identified as a protein ligand localized on the cell surface of transformed tumor cells. B7H6 binds specifically to the activating receptor NKp30, constitutively expressed on all resting and active NK cells. Upon ligand:receptor binding, B7H6 triggers NK cell activation and release of chemokines and pro-inflammatory cytokines such …

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Diversity Oriented Synthesis, Characterization And Anti-Cancer Activity Of Killer Peptide Nucleolipid Bioconjugates, Niki K. Rana May 2017

Diversity Oriented Synthesis, Characterization And Anti-Cancer Activity Of Killer Peptide Nucleolipid Bioconjugates, Niki K. Rana

Seton Hall University Dissertations and Theses (ETDs)

The killer peptide sequence D-(KLAKLAK)2 has been originally designed and developed as an antibacterial agent. Despite having excellent cytotoxicity towards bacteria, this sequence maintains low cell cytotoxity in malignant mammalian cell types such as cancer. The chemical basis for its selectivity has been attributed to its poly(cationic) amphiphilic nature, which facilitates cell permeability across the negatively charged bacterial membrane, but with limited permeability across the zwitterionic membrane of mammalian cells. The positively charged D-(KLAKLAK)2 sequence has been found to accumulate on the surface of the mitochondria causing dissipation of the negatively charged mitochondrial membrane potential. This charge disruption …

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Melatonin And Its Metabolites Protect Human Melanocytes Against Uvb-Induced Damage: Involvement Of Nrf2-Mediated Pathways, Zorica Janjetovic, Stuart G. Jarrett, Elizabeth F. Lee, Cory Duprey, Russel J. Reiter, Andrzej T. Slominski Apr 2017

Melatonin And Its Metabolites Protect Human Melanocytes Against Uvb-Induced Damage: Involvement Of Nrf2-Mediated Pathways, Zorica Janjetovic, Stuart G. Jarrett, Elizabeth F. Lee, Cory Duprey, Russel J. Reiter, Andrzej T. Slominski

Toxicology and Cancer Biology Faculty Publications

Ultraviolet light (UV) is an inducer of reactive oxygen species (ROS) as well as 6-4-photoproducts and cyclobutane pyrimidine dimers (CPD) in the skin, which further cause damage to the skin cells. Irradiation of cultured human melanocytes with UVB stimulated ROS production, which was reduced in cells treated with melatonin or its metabolites: 6-hydroxymelatonin (6-OHM), N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK), N-acetylserotonin (NAS), and 5-methoxytryptamine (5-MT). Melatonin and its derivatives also stimulated the expression of NRF2 (nuclear factor erythroid 2 [NF-E2]-related factor 2) and its target enzymes and proteins that play an important role in cell protection from different damaging factors including UVB. Silencing …

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Gene 33/Mig6 Regulates Apoptosis And The Dna Damage Response Through Independent Mechanisms, Cen Li, Soyoung Park, Leonard M. Eisenberg, Hong Zhao, Zbigniew Darzynkiewicz, Dazhong Xu Mar 2017

Gene 33/Mig6 Regulates Apoptosis And The Dna Damage Response Through Independent Mechanisms, Cen Li, Soyoung Park, Leonard M. Eisenberg, Hong Zhao, Zbigniew Darzynkiewicz, Dazhong Xu

NYMC Faculty Posters

Gene 33 (Mig6, ERRFI1) is an inducible adaptor/scaffold protein whose expression can be induced by both stress and mitogenic signals. It contains multiple domains for protein-protein interaction and is involved in a broad spectrum of cellular functions. Gene 33 promotes apoptosis in a cell type-dependent manner. A recent study has linked Gene 33 to the DNA damage response (DDR) induced by hexavalent chromium [Cr(VI)]. Here we show that Gene 33 induces apoptosis via both c-Abl/p73 and EGFR/AKT-dependent pathways in lung epithelial and lung carcinoma cells. Ectopic expression of Gene 33 also triggers DDR in an ATM-dependent fashion and through pathways …

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Aberrant Coordination Geometries Discovered In The Most Abundant Metalloproteins, Sen Yao, Robert M. Flight, Eric C. Rouchka, Hunter N. B. Moseley Mar 2017

Aberrant Coordination Geometries Discovered In The Most Abundant Metalloproteins, Sen Yao, Robert M. Flight, Eric C. Rouchka, Hunter N. B. Moseley

Molecular and Cellular Biochemistry Faculty Publications

Metalloproteins bind and utilize metal ions for a variety of biological purposes. Due to the ubiquity of metalloprotein involvement throughout these processes across all domains of life, how proteins coordinate metal ions for different biochemical functions is of great relevance to understanding the implementation of these biological processes. Toward these ends, we have improved our methodology for structurally and functionally characterizing metal binding sites in metalloproteins. Our new ligand detection method is statistically much more robust, producing estimated false positive and false negative rates of ∼0.11% and ∼1.2%, respectively. Additional improvements expand both the range of metal ions and their …

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Docking Studies Of Isoform-Selectivity Of Phosphatidylinositol 3-Kinase (Pi3k) Inhibitors, Kaitlin Goettsch Mar 2017

Docking Studies Of Isoform-Selectivity Of Phosphatidylinositol 3-Kinase (Pi3k) Inhibitors, Kaitlin Goettsch

UNO Student Research and Creative Activity Fair

Phosphatidylinositol 3-kinases (PI3Ks) and their related pathways are reputed targets for drug-based anticancer therapies. Mutations in PI3K genes, expression, and pathways are frequent among multiple cancer types. Four isoforms of PI3Ks exist: α, β, γ, & δ and studies have identified several ligands for each isoform which are capable of serving as inhibitory therapeutic compounds. However, the biochemical efficacy of these molecules varies and the isoform selectivity is not well understood. In this study, we applied in silico docking methods and free energy calculation methods to estimate the binding of reported PI3K ligands against 5 PI3K structures: PI3Kα (PBD ID: …

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Hendra Virus Fusion Protein Transmembrane Domain Contributes To Pre-Fusion Protein Stability, Stacy Webb, Tamas Nagy, Hunter Moseley, Michael G. Fried, Rebecca Ellis Dutch Feb 2017

Hendra Virus Fusion Protein Transmembrane Domain Contributes To Pre-Fusion Protein Stability, Stacy Webb, Tamas Nagy, Hunter Moseley, Michael G. Fried, Rebecca Ellis Dutch

Molecular and Cellular Biochemistry Faculty Publications

Enveloped viruses utilize fusion (F) proteins studding the surface of the virus to facilitate membrane fusion with a target cell membrane. Fusion of the viral envelope with a cellular membrane is required for release of viral genomic material, so the virus can ultimately reproduce and spread. To drive fusion, the F protein undergoes an irreversible conformational change, transitioning from a metastable pre-fusion conformation to a more thermodynamically stable post-fusion structure. Understanding the elements that control stability of the pre-fusion state and triggering to the post-fusion conformation is important for understanding F protein function. Mutations in F protein transmembrane (TM) domains …

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Dual-Functional-Tag-Facilitated Protein Labeling And Immobilization, Xinyi Zhang, Wei Lu, Kevin Kwan, Dibakar Bhattacharyya, Yinan Wei Feb 2017

Dual-Functional-Tag-Facilitated Protein Labeling And Immobilization, Xinyi Zhang, Wei Lu, Kevin Kwan, Dibakar Bhattacharyya, Yinan Wei

Chemistry Faculty Publications

An important strategy in the construction of biomimetic membranes and devices is to use natural proteins as the functional components for incorporation in a polymeric or nanocomposite matrix. Toward this goal, an important step is to immobilize proteins with high efficiency and precision without disrupting the protein function. Here, we developed a dual-functional tag containing histidine and the non-natural amino acid azidohomoalanine (AHA). AHA is metabolically incorporated into the protein, taking advantage of the Met-tRNA and Met-tRNA synthetase. Histidine in the tag can facilitate metal-affinity purification, whereas AHA can react with an alkyne-functionalized probe or surface via well-established click chemistry. …

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Editing Of Misaminoacylated Trna Controls The Sensitivity Of Amino Acid Stress Responses In Saccharomyces Cerevisiae, Kyle Mohler, Rebecca Mann, Tammy J. Bullwinkle, Kyle W. Hopkins, Lin Hwang, Noah M. Reynolds, Brandon Gassaway, Hans-Rudolph Aerni, Jesse Rinehart, Michael Polymenis, Kym F. Faull, Michael Ibba Feb 2017

Editing Of Misaminoacylated Trna Controls The Sensitivity Of Amino Acid Stress Responses In Saccharomyces Cerevisiae, Kyle Mohler, Rebecca Mann, Tammy J. Bullwinkle, Kyle W. Hopkins, Lin Hwang, Noah M. Reynolds, Brandon Gassaway, Hans-Rudolph Aerni, Jesse Rinehart, Michael Polymenis, Kym F. Faull, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Amino acid starvation activates the protein kinase Gcn2p, leading to changes in gene expression and translation. Gcn2p is activated by deacylated tRNA, which accumulates when tRNA aminoacylation is limited by lack of substrates or inhibition of synthesis. Pairing of amino acids and deacylated tRNAs is catalyzed by aminoacyl-tRNA synthetases, which use quality control pathways to maintain substrate specificity. Phenylalanyl-tRNA synthetase (PheRS) maintains specificity via an editing pathway that targets non-cognate Tyr-tRNAPhe. While the primary role of aaRS editing is to prevent misaminoacylation, we demonstrate editing of misaminoacylated tRNA is also required for detection of amino acid starvation by …

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Quality Control By Isoleucyl-Trna Synthetase Of Bacillus Subtilis Is Required For Efficient Sporulation, Elizabeth Kermgard, Zhou Yang, Annika-Marisa Michel, Rachel Simari, Jacqueline Wong, Michael Ibba, Beth A. Lazazzera Jan 2017

Quality Control By Isoleucyl-Trna Synthetase Of Bacillus Subtilis Is Required For Efficient Sporulation, Elizabeth Kermgard, Zhou Yang, Annika-Marisa Michel, Rachel Simari, Jacqueline Wong, Michael Ibba, Beth A. Lazazzera

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Isoleucyl-tRNA synthetase (IleRS) is an aminoacyl-tRNA synthetase whose essential function is to aminoacylate tRNAIle with isoleucine. Like some other aminoacyl-tRNA synthetases, IleRS can mischarge tRNAIle and correct this misacylation through a separate post-transfer editing function. To explore the biological significance of this editing function, we created a ileS(T233P) mutant of Bacillus subtilis that allows tRNAIle mischarging while retaining wild-type Ile-tRNAIle synthesis activity. As seen in other species defective for aminoacylation quality control, the growth rate of the ileS(T233P) strain was not significantly different from wild-type. When the ileS(T233P) strain was assessed for its ability to promote …

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Ms-Read: Quantitative Measurement Of Amino Acid Incorporation, Kyle Mohler, Hans-Rudolph Aerni, Brandon Gassaway, Jiqiang Ling, Michael Ibba, Jesse Rinehart Jan 2017

Ms-Read: Quantitative Measurement Of Amino Acid Incorporation, Kyle Mohler, Hans-Rudolph Aerni, Brandon Gassaway, Jiqiang Ling, Michael Ibba, Jesse Rinehart

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ribosomal protein synthesis results in the genetically programmed incorporation of amino acids into a growing polypeptide chain. Faithful amino acid incorporation that accurately reflects the genetic code is critical to the structure and function of proteins as well as overall proteome integrity. Errors in protein synthesis are generally detrimental to cellular processes yet emerging evidence suggest that proteome diversity generated through mistranslation may be beneficial under certain conditions. Cumulative translational error rates have been determined at the organismal level, however codon specific error rates and the spectrum of misincorporation errors from system to system remain largely unexplored. In particular, until …

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Maysin And Its Flavonoid Derivative From Centipedegrass Attenuates Amyloid Plaques By Inducting Humoral Immune Response With Th2 Skewed Cytokine Response In The Tg (Appswe, Ps1de9) Alzheimer's Mouse Model, Yuno Song, Hong-Duck Kim, Min-Kwon Lee, Il-Hwa Hong, Chung-Kil Won, Seung Sik Lee, Jae-Hyeon Cho Jan 2017

Maysin And Its Flavonoid Derivative From Centipedegrass Attenuates Amyloid Plaques By Inducting Humoral Immune Response With Th2 Skewed Cytokine Response In The Tg (Appswe, Ps1de9) Alzheimer's Mouse Model, Yuno Song, Hong-Duck Kim, Min-Kwon Lee, Il-Hwa Hong, Chung-Kil Won, Seung Sik Lee, Jae-Hyeon Cho

NYMC Faculty Publications

Alzheimer's disease (AD) is a slow, progressive neurodegenerative disease and the most common type of dementia in the elderly. The etiology of AD and its underlying mechanism are still not clear. In a previous study, we found that an ethyl acetate extract of Centipedegrass (CG) (i.e., EA-CG) contained 4 types of Maysin derivatives, including Luteolin, Isoorientin, Rhamnosylisoorientin, and Derhamnosylmaysin, and showed protective effects against Amyloid beta (Aβ) by inhibiting oligomeric Aβ in cellular and in vitro models. Here, we examined the preventative effects of EA-CG treatment on the Aβ burden in the Tg (Mo/Hu APPswe PS1dE9) AD mouse model. We …

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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 …

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Myeloperoxidase-Mediated Protein Lysine Oxidation Generates 2- Aminoadipic Acid And Lysine Nitrile In Vivo, Hongqiao Lin, Bruce S. Levison, Jennifer A. Buffa, Ying Huang, Xiaoming Fu, Zeneng Wang, Valentin Gogonea, Joseph A. Didonato, Stanley L. Hazen Jan 2017

Myeloperoxidase-Mediated Protein Lysine Oxidation Generates 2- Aminoadipic Acid And Lysine Nitrile In Vivo, Hongqiao Lin, Bruce S. Levison, Jennifer A. Buffa, Ying Huang, Xiaoming Fu, Zeneng Wang, Valentin Gogonea, Joseph A. Didonato, Stanley L. Hazen

Chemistry Faculty Publications

Recent studies reveal 2-aminoadipic acid (2-AAA) is both elevated in subjects at risk for diabetes and mechanistically linked to glucose homeostasis. Prior studies also suggest enrichment of protein-bound 2-AAA as an oxidative post-translational modification of lysyl residues in tissues associated with degenerative diseases of aging. While in vitro studies suggest redox active transition metals or myeloperoxidase (MPO) generated hypochlorous acid (HOCl) may produce protein-bound 2-AAA, the mechanism(s) responsible for generation of 2- AAA during inflammatory diseases are unknown. In initial studies we observed that traditional acid- or basecatalyzed protein hydrolysis methods previously employed to measure tissue 2-AAA can artificially generate …

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Molecular Modeling Of Novel Tryptamine Analogs With Antibiotic Potential Through Their Inhibition Of Tryptophan Synthase, Jared Schattenkerk Jan 2017

Molecular Modeling Of Novel Tryptamine Analogs With Antibiotic Potential Through Their Inhibition Of Tryptophan Synthase, Jared Schattenkerk

CMC Senior Theses

The growing prevalence of antibiotic-resistant bacteria is a global health crisis that threatens the effectiveness of antibiotics in medical treatment. Increases in the number of antibiotic-resistant bacteria and a drop in the pharmaceutical development of novel antibiotics have combined to form a situation that is rapidly increasing the likelihood of a post-antibiotic era. The development of antibiotics with novel enzymatic targets is critical to stall this growing crisis. In silico methods of molecular modeling and drug design were utilized in the development of novel tryptamine analogs as potential antibiotics through their inhibition of the bacterial enzyme tryptophan synthase. Following the …

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Synthesis Of Rhamnosylated Arginine Glycopeptides And Determination Of The Glycosidic Linkage In Bacterial Elongation Factor P, Siyao Wang, Leo Corcilius, Phillip B. Sharp, Andrei Rajkovic, Michael Ibba, Benjamin L. Parker, Richard J. Payne Dec 2016

Synthesis Of Rhamnosylated Arginine Glycopeptides And Determination Of The Glycosidic Linkage In Bacterial Elongation Factor P, Siyao Wang, Leo Corcilius, Phillip B. Sharp, Andrei Rajkovic, Michael Ibba, Benjamin L. Parker, Richard J. Payne

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A new class of N-linked protein glycosylation – arginine rhamnosylation – has recently been discovered as a critical modification for the function of bacterial elongation factor P (EF-P). Herein, we describe the synthesis of suitably protected α- and β-rhamnosylated arginine amino acid “cassettes” that can be directly installed into rhamnosylated peptides. Preparation of a proteolytic fragment of Pseudomonas aeruginosa EF-P bearing both α- and β-rhamnosylated arginine enabled the unequivocal determination of the native glycosidic linkage to be α through 2D NMR and nano-UHPLC-tandem mass spectrometry studies.

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The Complex Evolutionary History Of Aminoacyl-Trna Synthetases, Anargyros Chaliotis, Panayotis Vlastaridis, Dimitris Mossialos, Michael Ibba, Hubert D. Becker, Constantinos Stathopoulos, Grigorios D. Amoutzias Nov 2016

The Complex Evolutionary History Of Aminoacyl-Trna Synthetases, Anargyros Chaliotis, Panayotis Vlastaridis, Dimitris Mossialos, Michael Ibba, Hubert D. Becker, Constantinos Stathopoulos, Grigorios D. Amoutzias

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (AARSs) are a superfamily of enzymes responsible for the faithful translation of the genetic code and have lately become a prominent target for synthetic biologists. Our large-scale analysis of >2500 prokaryotic genomes reveals the complex evolutionary history of these enzymes and their paralogs, in which horizontal gene transfer played an important role. These results show that a widespread belief in the evolutionary stability of this superfamily is misconceived. Although AlaRS, GlyRS, LeuRS, IleRS, ValRS are the most stable members of the family, GluRS, LysRS and CysRS often have paralogs, whereas AsnRS, GlnRS, PylRS and SepRS are often absent …

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Isoacceptor Specific Characterization Of Trna Aminoacylation And Misacylation In Vivo, Kyle Mohler, Rebecca Mann, Michael Ibba Sep 2016

Isoacceptor Specific Characterization Of Trna Aminoacylation And Misacylation In Vivo, Kyle Mohler, Rebecca Mann, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Amino acid misincorporation during protein synthesis occurs due to misacylation of tRNAs or defects in decoding at the ribosome. While misincorporation of amino acids has been observed in a variety of contexts, less work has been done to directly assess the extent to which specific tRNAs are misacylated in vivo, and the identity of the misacylated amino acid moiety. Here we describe tRNA isoacceptor specific aminoacylation profiling (ISAP), a method to identify and quantify the amino acids attached to a tRNA species in vivo. ISAP allows compilation of aminoacylation profiles for specific isoacceptors tRNAs. To demonstrate the efficacy and …

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Maintenance Of Transcription-Translation Coupling By Elongation Factor P, Sara Elgamal, Irina Artsimovitch, Michael Ibba Sep 2016

Maintenance Of Transcription-Translation Coupling By Elongation Factor P, Sara Elgamal, Irina Artsimovitch, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Under conditions of tight coupling between translation and transcription, the ribosome enables synthesis of full-length mRNAs by preventing both formation of intrinsic terminator hairpins and loading of the transcription termination factor Rho. While previous studies have focused on transcription factors, we investigated the role of Escherichia coli elongation factor P (EF-P), an elongation factor required for efficient translation of mRNAs containing consecutive proline codons, in maintaining coupled translation and transcription. In the absence of EF-P, the presence of Rho utilization (rut) sites led to an ~30-fold decrease in translation of polyproline-encoding mRNAs. Coexpression of the Rho inhibitor Psu …

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Translation Control Of Swarming Proficiency In Bacillus Subtilis By 5-Amino-Pentanolylated Elongation Factor P, Andrei Rajkovic, Katherine R. Hummels, Anne Witzky, Sarah Erickson, Philip R. Gafken, Julian P. Whitelegge, Kym F. Faull, Daniel B. Kearns, Michael Ibba May 2016

Translation Control Of Swarming Proficiency In Bacillus Subtilis By 5-Amino-Pentanolylated Elongation Factor P, Andrei Rajkovic, Katherine R. Hummels, Anne Witzky, Sarah Erickson, Philip R. Gafken, Julian P. Whitelegge, Kym F. Faull, Daniel B. Kearns, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) accelerates diprolyl synthesis and requires a posttranslational modification to maintain proteostasis. Two phylogenetically distinct EF-P modification pathways have been described and are encoded in the majority of Gram-negative bacteria, but neither is present in Gram-positive bacteria. Prior work suggested that the EF-P-encoding gene (efp) primarily supports Bacillus subtilis swarming differentiation, whereas EF-P in Gram-negative bacteria has a more global housekeeping role, prompting our investigation to determine whether EF-P is modified and how it impacts gene expression in motile cells. We identified a 5-aminopentanol moiety attached to Lys32 of B. subtilis EF-P that is …

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Multiple Quality Control Pathways Limit Non-Protein Amino Acid Use By Yeast Cytoplasmic Phenylalanyl-Trna Synthetase, Adil Moghal, Lin Hwang, Kym F. Faull, Michael Ibba May 2016

Multiple Quality Control Pathways Limit Non-Protein Amino Acid Use By Yeast Cytoplasmic Phenylalanyl-Trna Synthetase, Adil Moghal, Lin Hwang, Kym F. Faull, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Non-protein amino acids, particularly isomers of the proteinogenic amino acids, present a threat to proteome integrity if they are mistakenly inserted into proteins. Quality control during aminoacyl-tRNA synthesis reduces non-protein amino acid incorporation by both substrate discrimination and proofreading. For example phenylalanyl-tRNA synthetase (PheRS) proofreads the non-protein hydroxylated phenylalanine derivative m-Tyr after its attachment to tRNAPhe. We now show in Saccharomyces cerevisiae that PheRS misacylation of tRNAPhe with the more abundant Phe oxidation product o-Tyr is limited by kinetic discrimination against o-Tyr-AMP in the transfer step followed by o-Tyr-AMP release from the synthetic …

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Non-Canonical Roles Of Trnas And Trna Mimics In Bacterial Cell Biology, Assaf Katz, Sara Elgamal, Andrei Rajkovic, Michael Ibba May 2016

Non-Canonical Roles Of Trnas And Trna Mimics In Bacterial Cell Biology, Assaf Katz, Sara Elgamal, Andrei Rajkovic, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Transfer RNAs (tRNAs) are the macromolecules that transfer activated amino acids from aminoacyl‐tRNA synthetases to the ribosome, where they are used for the mRNA guided synthesis of proteins. Transfer RNAs are ancient molecules, perhaps even predating the existence of the translation machinery. Albeit old, these molecules are tremendously conserved, a characteristic that is well illustrated by the fact that some bacterial tRNAs are efficient and specific substrates of eukaryotic aminoacyl‐tRNA synthetases and ribosomes. Considering their ancient origin and high structural conservation, it is not surprising that tRNAs have been hijacked during evolution for functions outside of translation. These roles beyond …

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Zn(Ii), Cu(Ii), Sn(Ii), And Ni(Ii) And Other Metal Cations Do Not Prevent The Aggregation Of Hiapp, Charles Hoying May 2016

Zn(Ii), Cu(Ii), Sn(Ii), And Ni(Ii) And Other Metal Cations Do Not Prevent The Aggregation Of Hiapp, Charles Hoying

Honors Thesis

The Zn(II) metal ion has been shown to interact with Islet Amyloid Polypeptide (IAPP), a protein implicated in the progression of Type II Diabetes Mellitus, in such a way as to prevent the protein from aggregating into toxic fibers. We set out to find whether other metal ions might similarly prevent IAPP aggregation. Using Thioflavin T (ThT) spectroscopic assays, which measure fluorescence of ThT upon binding to aggregated IAPP, we observed a decrease in aggregation when incubated with Zn(II), Cu(II), Ni(II), and Sn(II). Atomic Force Microscopy (AFM), which can visualize fibril formation, revealed that the metals were not inhibiting IAPP …

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Engineering A Mutation In The Heparin Binding Pocket Of The Human Fibroblast Growth Factor, Roshni Patel May 2016

Engineering A Mutation In The Heparin Binding Pocket Of The Human Fibroblast Growth Factor, Roshni Patel

Chemistry & Biochemistry Undergraduate Honors Theses

Fibroblast growth factors (FGFs) are family of proteins that belong to a group of growth factors that are found in mammals and play an important role in angiogenesis, differentiation, organogenesis, and tissue repair. In summary, their main functionality is involved in cell division and proliferation. Because FGFs plays such a vital role in cell proliferation, they are mainly involved in the process of wound healing and injuries. FGF binds to its ligand, heparin—a heavily sulfated glycosaminoglycan. The binding of heparin to FGF occurs through electrostatic interactions, specifically between the negatively charged sulfate groups on heparin and positively charged residues such …

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Synthesis And Characterization Of Nanoparticle-Coupled Proteins In Human Serum Albumin, Kyle M. Mahoney Apr 2016

Synthesis And Characterization Of Nanoparticle-Coupled Proteins In Human Serum Albumin, Kyle M. Mahoney

Honors College Theses

Recently, cancer has become an ever-growing issue and has led to many researchers attempt to unravel the mystery of the disease. This research has led to a promising field of treatment: nanotechnology-coupled pharmaceuticals. Nanoparticles act as a whole unit when in conjugation with other molecules and add to the carrier molecule, most often proteins, benefits the nanoparticles themselves possess. One such carrier protein that can be conjugated with nanoparticles is Human Serum Albumin (HSA). Albumin is of interest in cancer research for two reasons: it is native to the human vasculature so it does not elicit immunological reactions, and it …

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Novel Compound Heterozygous Mutations Expand The Recognized Phenotypes Of Fars2-Linked Disease, Melissa A. Walker, Kyle Mohler, Kyle W. Hopkins, Derek H. Oakley, David A. Sweetser, Michael Ibba, Matthew P. Frosch, Ronald L. Thibert Apr 2016

Novel Compound Heterozygous Mutations Expand The Recognized Phenotypes Of Fars2-Linked Disease, Melissa A. Walker, Kyle Mohler, Kyle W. Hopkins, Derek H. Oakley, David A. Sweetser, Michael Ibba, Matthew P. Frosch, Ronald L. Thibert

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Mutations in mitochondrial aminoacyl-tRNA synthetases are an increasingly recognized cause of human diseases, often arising in individuals with compound heterozygous mutations and presenting with system-specific phenotypes, frequently neurologic. FARS2 encodes mitochondrial phenylalanyl transfer ribonucleic acid (RNA) synthetase (mtPheRS), perturbations of which have been reported in 6 cases of an infantile, lethal disease with refractory epilepsy and progressive myoclonus. Here the authors report the case of juvenile onset refractory epilepsy and progressive myoclonus with compound heterozygous FARS2 mutations. The authors describe the clinical course over 6 years of care at their institution and diagnostic studies including electroencephalogram (EEG), brain magnetic resonance …

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Dancing Through Life: Molecular Dynamics Simulations And Network-Centric Modeling Of Allosteric Mechanisms In Hsp70 And Hsp110 Chaperone Proteins, Gabrielle Stetz, Gennady M. Verkhivker Nov 2015

Dancing Through Life: Molecular Dynamics Simulations And Network-Centric Modeling Of Allosteric Mechanisms In Hsp70 And Hsp110 Chaperone Proteins, Gabrielle Stetz, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Hsp70 and Hsp110 chaperones play an important role in regulating cellular processes that involve protein folding and stabilization, which are essential for the integrity of signaling networks. Although many aspects of allosteric regulatory mechanisms in Hsp70 and Hsp110 chaperones have been extensively studied and significantly advanced in recent experimental studies, the atomistic picture of signal propagation and energetics of dynamics-based communication still remain unresolved. In this work, we have combined molecular dynamics simulations and protein stability analysis of the chaperone structures with the network modeling of residue interaction networks to characterize molecular determinants of allosteric mechanisms. We have shown that …

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