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

Biochemistry, Biophysics, and Structural Biology Commons

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

Biotechnology

2012

Institution
Keyword
Publication
Publication Type
File Type

Articles 1 - 30 of 50

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

Crystal Structures And Kinetics Of Monofunctional Proline Dehydrogenase Provide Insight Into Substrate Recognition And Conformational Changes Associated With Flavin Reduction And Product Release, Min Luo, Benjamin W. Arentson, Dhiraj Srivastava, Donald F. Becker, John J. Tanner Dec 2012

Crystal Structures And Kinetics Of Monofunctional Proline Dehydrogenase Provide Insight Into Substrate Recognition And Conformational Changes Associated With Flavin Reduction And Product Release, Min Luo, Benjamin W. Arentson, Dhiraj Srivastava, Donald F. Becker, John J. Tanner

Biochemistry -- Faculty Publications

Proline dehydrogenase catalyzes the FAD-dependent oxidation of proline to Δ1- pyrroline-5- carboxylate, which is the first step of proline catabolism. Here, we report the structures of proline dehydrogenase from Deinococcus radiodurans in the oxidized state complexed with the proline analog L-tetrahydrofuroic acid and in the reduced state with the proline site vacant. The analog binds against the si face of the FAD isoalloxazine and is protected from bulk solvent by the α8 helix and the β1-α1 loop. The FAD ribityl chain adopts two conformations in the E-S complex, which is unprecedented for flavoenzymes. One of the conformations is novel for ...


Genome-Wide Association Study For Oat (Avena Sativa L.) Beta-Glucan Concentration Using Germplasm Of Worldwide Origin, Mark A. Newell, Franco G. Asoro, M. Paul Scott, Pamela J. White, William D. Beavis, Jean-Luc Jannink Dec 2012

Genome-Wide Association Study For Oat (Avena Sativa L.) Beta-Glucan Concentration Using Germplasm Of Worldwide Origin, Mark A. Newell, Franco G. Asoro, M. Paul Scott, Pamela J. White, William D. Beavis, Jean-Luc Jannink

Food Science and Human Nutrition Publications

Detection of quantitative trait loci (QTL) controlling complex traits followed by selection has become a common approach for selection in crop plants. The QTL are most often identified by linkage mapping using experimental F2, backcross, advanced inbred, or doubled haploid families. An alternative approach for QTL detection are genome-wide association studies (GWAS) that use pre-existing lines such as those found in breeding programs. We explored the implementation of GWAS in oat (Avena sativa L.) to identify QTL affecting β-glucan concentration, a soluble dietary fiber with several human health benefits when consumed as a whole grain. A total of 431 lines ...


Knockout Of The 15 Kda Selenoprotein Protects Against Chemically-Induced Aberrant Crypt Formation In Mice, Petra A. Tsuji, Bradley A. Carlson, Salvador Naranjo-Suarez, Min-Hyuk Yoo, Xue-Ming Xu, Dmitri E. Fomenko, Vadim Gladyshev, Dolph L. Hatfield, Cindy D. Davis Dec 2012

Knockout Of The 15 Kda Selenoprotein Protects Against Chemically-Induced Aberrant Crypt Formation In Mice, Petra A. Tsuji, Bradley A. Carlson, Salvador Naranjo-Suarez, Min-Hyuk Yoo, Xue-Ming Xu, Dmitri E. Fomenko, Vadim Gladyshev, Dolph L. Hatfield, Cindy D. Davis

Biochemistry -- Faculty Publications

Evidence suggests that selenium has cancer preventive properties that are largely mediated through selenoproteins. Our previous observations demonstrated that targeted down-regulation of the 15 kDa selenoprotein (Sep15) in murine colon cancer cells resulted in the reversal of the cancer phenotype. The present study investigated the effect of Sep15 knockout in mice using a chemically-induced colon cancer model. Homozygous Sep15 knockout mice, and wild type littermate controls were given four weekly subcutaneous injections of azoxymethane (10 mg/kg). Sep15 knockout mice developed significantly (pGBP-1 in humans has been associated with a highly significant, increased five-year survival rate in colorectal cancer patients ...


Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu Nov 2012

Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu

Weiqiang Chen

Circulating tumor cells (CTCs) detached from both primary and metastatic lesions represent a potential alternative to invasive biopsies as a source of tumor tissue for the detection, characterization and monitoring of cancers. Here we report a simple yet effective strategy for capturing CTCs without using capture antibodies. Our method uniquely utilized the differential adhesion preference of cancer cells to nanorough surfaces when compared to normal blood cells and thus did not depend on their physical size or surface protein expression, a significant advantage as compared to other existing CTC capture techniques.


Cross Regulation Of Sirtuin 1, Ampk, And Ppary In Conjugated Linoleic Acid Treated Adipocytes, Shan Jiang, Wei Wang, Jess Miner, Michael E. Fromm Nov 2012

Cross Regulation Of Sirtuin 1, Ampk, And Ppary In Conjugated Linoleic Acid Treated Adipocytes, Shan Jiang, Wei Wang, Jess Miner, Michael E. Fromm

Biochemistry -- Faculty Publications

Trans-10, cis-12 conjugated linoleic acid (t10c12 CLA) reduces triglyceride (TG) levels in adipocytes through multiple pathways, with AMP-activated protein kinase (AMPK) generally facilitating, and peroxisome proliferator-activated receptor γ (PPARγ) generally opposing these reductions. Sirtuin 1 (SIRT1), a histone/protein deacetylase that affects energy homeostasis, often functions coordinately with AMPK, and is capable of binding to PPARγ, thereby inhibiting its activity. This study investigated the role of SIRT1 in the response of 3T3-L1 adipocytes to t10c12 CLA by testing the following hypotheses: 1) SIRT1 is functionally required for robust TG reduction; and 2) SIRT1 ...


Purification And Characterization Of Novel Nucleases From A Thermophilic Fungus, Kyle Landry Sep 2012

Purification And Characterization Of Novel Nucleases From A Thermophilic Fungus, Kyle Landry

Kyle S Landry

A thermophilic fungus was isolated from composted horse manure. The organism was as a Chaetomium sp. by sequencing the highly conserved ITS region of the fungus and comparing to known regions in a genomic database and was referred to as TM-417. TM-417 was found to have an optimal growth temperature of 45 oC and an optimal pH of 7.0. An extracellular DNase and RNase was found to be produced by the isolate and were purified 145.58-fold and 127.6-fold respectively using a combination of size exclusion chromatography and a novel affinity membrane purification system. The extent of ...


Sex Determination In Beetles: Production Of All Male Progeny By Parental Rnai Knockdown Of Transformer, Jayendra Nath Shukla, Subba Reddy Palli Aug 2012

Sex Determination In Beetles: Production Of All Male Progeny By Parental Rnai Knockdown Of Transformer, Jayendra Nath Shukla, Subba Reddy Palli

Entomology Faculty Publications

Sex in insects is determined by a cascade of regulators ultimately controlling sex-specific splicing of a transcription factor, Doublesex (Dsx). We recently identified homolog of dsx in the red flour beetle, Tribolium castaneum (Tcdsx). Here, we report on the identification and characterization of a regulator of Tcdsx splicing in T. castaneum. Two male-specific and one female-specific isoforms of T. castaneum transformer (Tctra) were identified. RNA interference-aided knockdown of Tctra in pupa or adults caused a change in sex from females to males by diverting the splicing of Tcdsx pre-mRNA to male-specific isoform. All the pupa and adults developed from Tctra ...


Protein Body Formation In Stable Transgenic Plants Of Nicotiana Tabacum Expressing Elastin-Like Polypeptide And Hydrophobin Fusion Proteins, Sonia P. Gutierrez Aug 2012

Protein Body Formation In Stable Transgenic Plants Of Nicotiana Tabacum Expressing Elastin-Like Polypeptide And Hydrophobin Fusion Proteins, Sonia P. Gutierrez

Electronic Thesis and Dissertation Repository

Plants are recognized as an efficient and inexpensive system to produce valuable recombinant proteins. However, the use of plants still faces two main limitations: the low accumulation levels of some recombinant proteins and the lack of efficient protein purification methods. Two fusion partners, elastin-like polypeptides (ELP) and hydrophobin I (HFBI) were found to increase the accumulation of recombinant proteins and induce the formation of protein bodies (PBs) when targeted to the ER in transient expression assays. In this study I examined the effect of these tags in stable transgenic plants of two Nicotiana tabacum cultivars when fused to green fluorescent ...


Analyzing Environmental Microbes For Genomic Regions Promoting Ionic Liquid Tolerance In E. Coli, Ann Nguyen, Alison Richins, Thomas Rüegg, Steven Singer, Michael Thelen Aug 2012

Analyzing Environmental Microbes For Genomic Regions Promoting Ionic Liquid Tolerance In E. Coli, Ann Nguyen, Alison Richins, Thomas Rüegg, Steven Singer, Michael Thelen

STAR (STEM Teacher and Researcher) Presentations

Ionic liquids (ILs) are promising as solvents to increase the efficiency of biofuel production; however, ILs are toxic to microbes used in the fermentation of liquid fuels. To engineer IL resistant biofuel hosts, environmental bacteria were screened for tolerance, and these were used to create gene libraries to test in E. coli. Future characterization of these libraries using molecular techniques will be used to identify genes that contribute IL-tolerance to transformed microbes.


Quantification And In Vitro Analysis Of Nanolipoproteins (Nlps) Containing Adjuvants, Purna Venkataraman, Craig Blanchette, Nicholas O. Fischer Aug 2012

Quantification And In Vitro Analysis Of Nanolipoproteins (Nlps) Containing Adjuvants, Purna Venkataraman, Craig Blanchette, Nicholas O. Fischer

STAR (STEM Teacher and Researcher) Presentations

Nanolipoprotein particles (NLPs) self-assemble into nanoscale structures that can be used as vaccines or drug delivery agents. Due to the nature of the NLPs, a variety of immune stimulating compounds or adjuvants can be readily incorporated into NLPs: a characteristic difficult to engineer into most other nanoscale platforms. In light of this, a method for quantifying the amount adjuvant actually incorporated into NLPs is a question of high importance. Through the use of reverse phase High-Performance Liquid Chromatography (HPLC) and an Evaporative Light Scattering Detector (ELSD), standard curves can be constructed by analyzing mixtures of NLP components of known concentration ...


Urinary Copper Elevation In A Mouse Model Of Wilson’S Disease Is A Regulated Process To Specifically Decrease The Hepatic Copper Load, Lawrence W. Gray, Fangyu Peng, Shannon A. Molloy, Venkata S. Pendyala, Abigael Muchenditsi, Otto Muzik, Jaekwon Lee, Jack H. Kaplan, Svetlana Lutsenko Jun 2012

Urinary Copper Elevation In A Mouse Model Of Wilson’S Disease Is A Regulated Process To Specifically Decrease The Hepatic Copper Load, Lawrence W. Gray, Fangyu Peng, Shannon A. Molloy, Venkata S. Pendyala, Abigael Muchenditsi, Otto Muzik, Jaekwon Lee, Jack H. Kaplan, Svetlana Lutsenko

Biochemistry -- Faculty Publications

Body copper homeostasis is regulated by the liver, which removes excess copper via bile. In Wilson’s disease (WD), this function is disrupted due to inactivation of the copper transporter ATP7B resulting in hepatic copper overload. High urinary copper is a diagnostic feature of WD linked to liver malfunction; the mechanism behind urinary copper elevation is not fully understood. Using Positron Emission Tomography-Computed Tomography (PET-CT) imaging of live Atp7b/ mice at different stages of disease, a longitudinal metal analysis, and characterization of copper-binding molecules, we show that urinary copper elevation is a specific regulatory process mediated by distinct ...


Conservation Of Oxidative Protein Stabilization In An Insect Homologue Of The Parkinsonism-Associated Protein Dj-1, Jiusheng Lin, Janani Prahlad, Mark A. Wilson May 2012

Conservation Of Oxidative Protein Stabilization In An Insect Homologue Of The Parkinsonism-Associated Protein Dj-1, Jiusheng Lin, Janani Prahlad, Mark A. Wilson

Biochemistry -- Faculty Publications

DJ-1 is a conserved, disease-associated protein that protects against oxidative stress and mitochondrial damage in multiple organisms. Human DJ-1 contains a functionally essential cysteine residue (Cys106) whose oxidation is important for regulating protein function by an unknown mechanism. This residue is well conserved in other DJ-1 homologues, including two (DJ-1α and DJ-1β) in Drosophila melanogaster. Because D. melanogaster is a powerful model system for studying DJ-1 function, we have determined the crystal structure and impact of cysteine oxidation on Drosophila DJ-1β. The structure of D. melanogaster DJ-1β is similar to that of human DJ-1, although two important residues in the ...


Synthesis, Characterization And Self-Assembly Of Amphiphilic Block Copolymers, Xiaojun Wang May 2012

Synthesis, Characterization And Self-Assembly Of Amphiphilic Block Copolymers, Xiaojun Wang

Doctoral Dissertations

This dissertation presents a review on state-of-the-art research of well-defined charged block copolymers, including synthesis, characterization, bulk morphology and self-assembly in aqueous solution of amphiphilic block polyelectrolytes. In Chapter 1, as a general introduction, experimental observations and theoretical calculations devoted towards understanding morphological behavior in charged block copolymer systems are reviewed along with some of the new emerging research directions. Further investigation of charged systems is urged in order to fully understand their morphological behavior and to directly target structures for the tremendous potential in technological applications. Following this background, in Chapters 2, 3, 4 and 5 are presented the ...


Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu Apr 2012

Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu

Weiqiang Chen

Human embryonic stem cells (hESCs) have great potentials for future cell-based therapeutics. However, their mechanosensitivity to biophysical signals from the cellular microenvironment is not well characterized. Here we introduced an effective microfabrication strategy for accurate control and patterning of nanoroughness on glass surfaces. Our results demonstrated that nanotopography could provide a potent regulatory signal over different hESC behaviors, including cell morphology, adhesion, proliferation, clonal expansion, and self-renewal. Our results indicated that topological sensing of hESCs might include feedback regulation involving mechanosensory integrin-mediated cell matrix adhesion, myosin II, and E-cadherin. Our results also demonstrated that cellular responses to nanotopography were cell-type ...


Composition And Evolution Of The Vertebrate And Mammalian Selenoproteomes, Marco Mariotti, Perry G. Ridge, Yan Zhang, Alexei V. Lobanov, Thomas H. Pringle, Roderic Guigo, Dolph L. Hatfield, Vadim N. Gladyshev Mar 2012

Composition And Evolution Of The Vertebrate And Mammalian Selenoproteomes, Marco Mariotti, Perry G. Ridge, Yan Zhang, Alexei V. Lobanov, Thomas H. Pringle, Roderic Guigo, Dolph L. Hatfield, Vadim N. Gladyshev

Biochemistry -- Faculty Publications

Background: Selenium is an essential trace element in mammals due to its presence in proteins in the form of selenocysteine (Sec). Human genome codes for 25 Sec-containing protein genes, and mouse and rat genomes for 24.

Methodology/Principal Findings: We characterized the selenoproteomes of 44 sequenced vertebrates by applying gene prediction and phylogenetic reconstruction methods, supplemented with the analyses of gene structures, alternative splicing isoforms, untranslated regions, SECIS elements, and pseudogenes. In total, we detected 45 selenoprotein subfamilies. 28 of them were found in mammals, and 41 in bony fishes. We define the ancestral vertebrate (28 proteins) and mammalian (25 ...


Metabolomics As A Hypothesis-Generating Functional Genomics Tool For The Annotation Of Arabidopsis Thaliana Genes Of “Unknown Function”, Stephanie M. Quanbeck, Libuse Brachova, Alexis A. Campbell, Xin Guan, Ann Perera, Kun He, Seung Y. Rhee, Preeti Bais, Julie A. Dickerson, Philip M. Dixon, Gert Wohlgemuth, Oliver Fiehn, Lenore Barkan, Iris Lange, B. Markus Lange, Insuk Lee, Diego Cortes, Carolina Salazar, Joel Shuman, Vladimir Shulaev, David V. Huhman, Lloyd W. Sumner, Mary R. Roth, Ruth Welti, Hilal Ilarslan, Eve S. Wurtele, Basil J. Nikolau Feb 2012

Metabolomics As A Hypothesis-Generating Functional Genomics Tool For The Annotation Of Arabidopsis Thaliana Genes Of “Unknown Function”, Stephanie M. Quanbeck, Libuse Brachova, Alexis A. Campbell, Xin Guan, Ann Perera, Kun He, Seung Y. Rhee, Preeti Bais, Julie A. Dickerson, Philip M. Dixon, Gert Wohlgemuth, Oliver Fiehn, Lenore Barkan, Iris Lange, B. Markus Lange, Insuk Lee, Diego Cortes, Carolina Salazar, Joel Shuman, Vladimir Shulaev, David V. Huhman, Lloyd W. Sumner, Mary R. Roth, Ruth Welti, Hilal Ilarslan, Eve S. Wurtele, Basil J. Nikolau

Biochemistry, Biophysics and Molecular Biology Publications

Metabolomics is the methodology that identifies and measures global pools of small molecules (of less than about 1,000 Da) of a biological sample, which are collectively called the metabolome. Metabolomics can therefore reveal the metabolic outcome of a genetic or environmental perturbation of a metabolic regulatory network, and thus provide insights into the structure and regulation of that network. Because of the chemical complexity of the metabolome and limitations associated with individual analytical platforms for determining the metabolome, it is currently difficult to capture the complete metabolome of an organism or tissue, which is in contrast to genomics and ...


Imaging And Aesthetics, Allison Marsh Jan 2012

Imaging And Aesthetics, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.


Spotlight On Usc: A.C. Moore Herbarium, Allison Marsh Jan 2012

Spotlight On Usc: A.C. Moore Herbarium, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.


Why Do We Collect?, Allison Marsh Jan 2012

Why Do We Collect?, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.


Conclusion Panel, Allison Marsh Jan 2012

Conclusion Panel, Allison Marsh

Section 6: Conclusion

No abstract provided.


Integrative Bayesian Analysis Of High-Dimensional Multi-Platform Genomics Data, Wenting Wang, Veerabhadran Baladandayuthapani, Jeffrey S. Morris, Bradley M. Broom, Ganiraju C. Manyam, Kim-Anh Do Jan 2012

Integrative Bayesian Analysis Of High-Dimensional Multi-Platform Genomics Data, Wenting Wang, Veerabhadran Baladandayuthapani, Jeffrey S. Morris, Bradley M. Broom, Ganiraju C. Manyam, Kim-Anh Do

Jeffrey S. Morris

Motivation: Analyzing data from multi-platform genomics experiments combined with patients’ clinical outcomes helps us understand the complex biological processes that characterize a disease, as well as how these processes relate to the development of the disease. Current integration approaches that treat the data are limited in that they do not consider the fundamental biological relationships that exist among the data from platforms.

Statistical Model: We propose an integrative Bayesian analysis of genomics data (iBAG) framework for identifying important genes/biomarkers that are associated with clinical outcome. This framework uses a hierarchical modeling technique to combine the data obtained from multiple ...


Purification And Characterization Of Novel Nucleases From A Thermophilic Fungus, Kyle S. Landry Jan 2012

Purification And Characterization Of Novel Nucleases From A Thermophilic Fungus, Kyle S. Landry

Masters Theses 1911 - February 2014

A thermophilic fungus was isolated from composted horse manure. The organism was as a Chaetomium sp. by sequencing the highly conserved ITS region of the fungus and comparing to known regions in a genomic database and was referred to as TM-417. TM-417 was found to have an optimal growth temperature of 45 oC and an optimal pH of 7.0. An extracellular DNase and RNase was found to be produced by the isolate and were purified 145.58-fold and 127.6-fold respectively using a combination of size exclusion chromatography and a novel affinity membrane purification system. The extent of ...


Structure, Function, And Assembly Of Heme Centers In Mitochondrial Respiratory Complexes, Hyung J. Kim, Oleh Khalimonchuk, Pamela M. Smith, Dennis R. Winge Jan 2012

Structure, Function, And Assembly Of Heme Centers In Mitochondrial Respiratory Complexes, Hyung J. Kim, Oleh Khalimonchuk, Pamela M. Smith, Dennis R. Winge

Biochemistry -- Faculty Publications

The sequential flow of electrons in the respiratory chain, from a low reduction potential substrate to O2, is mediated by protein-bound redox cofactors. In mitochondria, hemes—together with flavin, iron–sulfur, and copper cofactors—mediate this multi-electron transfer. Hemes, in three different forms, are used as a protein-bound prosthetic group in succinate dehydrogenase (complex II), in bc1 complex (complex III) and in cytochrome c oxidase (complex IV). The exact function of heme b in complex II is still unclear, and lags behind in operational detail that is available for the hemes of complex III and IV. The two ...


A Novel Link Between Akt1 And Twist1 In Ovarian Tumor Cell Motility And Invasiveness, Nirav Shah Jan 2012

A Novel Link Between Akt1 And Twist1 In Ovarian Tumor Cell Motility And Invasiveness, Nirav Shah

Electronic Theses and Dissertations

Ovarian cancer results in more deaths per year than any other cancer of the female reproductive system. The low survival rate is partly due to the lack of early detection and the susceptibility to relapse. The AKT serine threonine kinase plays a pivotal role in hallmark cellular processes for the progression of ovarian cancer, including tumor cell growth and migration. Therapeutic targeting of pan-AKT has been problematic, in part due to feedback mechanisms and crosstalk with other pathways. The hypothesis for this study is that AKT 1, -2 and -3 isoforms may have different roles and regulate cell processes in ...


Expression Of Lipase From Mycobacterium Tuberculosis In Nicotiana Tobacum And Lactuca Sativa Chloroplasts, Bethany Lloyd Jan 2012

Expression Of Lipase From Mycobacterium Tuberculosis In Nicotiana Tobacum And Lactuca Sativa Chloroplasts, Bethany Lloyd

Electronic Theses and Dissertations

Tuberculosis (TB), caused by the bacterium Mycobacterium tuberculosis (M. tuberculosis), is a global threat and the leading cause of death among individuals infected with HIV. TB treatment requires multi-drug cocktails, due to the increasing rates of drug resistance of the bacterium. With multi-drug cocktails, strains have been documented to be resistant to all major drugs in the fight against TB. Since the strains are drug resistant, it calls for an increasing need for vaccine and treatment development for the purpose of preventing and managing the disease. The most widely distributed vaccine against TB is Bacillus Calmette-Gue´rin (BCG). Apart from ...


The Evolutionary Rewiring Of Ubiquitination Targets Has Reprogrammed The Regulation Of Carbon Assimilation In The Pathogenic Yeast Candida Albicans, Doblin Sandai, Zhikang Yin, Laura Selway, David Stead, Janet Walker, Michelle D. Leach, Iryna Bohovych, Iuliana V. Ene, Stavroula Kastora, Susan Budge, Carol A. Munro, Frank C. Odds, Neil A.R. Gow, Alistair J.P. Brown Jan 2012

The Evolutionary Rewiring Of Ubiquitination Targets Has Reprogrammed The Regulation Of Carbon Assimilation In The Pathogenic Yeast Candida Albicans, Doblin Sandai, Zhikang Yin, Laura Selway, David Stead, Janet Walker, Michelle D. Leach, Iryna Bohovych, Iuliana V. Ene, Stavroula Kastora, Susan Budge, Carol A. Munro, Frank C. Odds, Neil A.R. Gow, Alistair J.P. Brown

Biochemistry -- Faculty Publications

Microbes must assimilate carbon to grow and colonize their niches. Transcript profiling has suggested that Candida albicans, a major pathogen of humans, regulates its carbon assimilation in an analogous fashion to the model yeast Saccharomyces cerevisiae, repressing metabolic pathways required for the use of alterative nonpreferred carbon sources when sugars are available. However, we show that there is significant dislocation between the proteome and transcriptome in C. albicans. Glucose triggers the degradation of the ICL1 and PCK1 transcripts in C. albicans, yet isocitrate lyase (Icl1) and phosphoenolpyruvate carboxykinase (Pck1) are stable and are retained. Indeed, numerous enzymes required for the ...


Proline Dehydrogenase Is Essential For Proline Protection Against Hydrogen Peroxide Induced Cell Death, Sathish Kumar Natarajan, Weidong Zhu, Xinwen Liang, Lu Zhang, Andrew Demers, Matthew C. Zimmerman, Melanie A. Simpson, Donald F. Becker Jan 2012

Proline Dehydrogenase Is Essential For Proline Protection Against Hydrogen Peroxide Induced Cell Death, Sathish Kumar Natarajan, Weidong Zhu, Xinwen Liang, Lu Zhang, Andrew Demers, Matthew C. Zimmerman, Melanie A. Simpson, Donald F. Becker

Biochemistry -- Faculty Publications

Proline metabolism has an underlying role in apoptotic signaling that impacts tumorigenesis. Proline is oxidized to glutamate in the mitochondria with the rate limiting step catalyzed by proline dehydrogenase (PRODH). PRODH expression is inducible by p53 leading to increased proline oxidation, reactive oxygen species (ROS) formation, and induction of apoptosis. Paradoxical to its role in apoptosis, proline also protects cells against oxidative stress. Here we explore the mechanism of proline protection against hydrogen peroxide stress in melanoma WM35 cells. Treatment of WM35 cells with proline significantly increased cell viability, diminished oxidative damage of cellular lipids and proteins, and retained ATP ...


Late-Stage Maturation Of The Rieske Fe/S Protein: Mzm1 Stabilizes Rip1 But Does Not Facilitate Its Translocation By The Aaa Atpase Bcs1, Tie-Zhong Cui, Pamela M. Smith, Jennifer L. Fox, Oleh Khalimonchuk, Dennis R. Winge Jan 2012

Late-Stage Maturation Of The Rieske Fe/S Protein: Mzm1 Stabilizes Rip1 But Does Not Facilitate Its Translocation By The Aaa Atpase Bcs1, Tie-Zhong Cui, Pamela M. Smith, Jennifer L. Fox, Oleh Khalimonchuk, Dennis R. Winge

Biochemistry -- Faculty Publications

The final step in the assembly of the ubiquinol-cytochrome c reductase or bc1 complex involves the insertion of the Rieske Fe/S cluster protein, Rip1. Maturation of Rip1 occurs within the mitochondrial matrix prior to its translocation across the inner membrane (IM) in a process mediated by the Bcs1 ATPase and subsequent insertion into the bc1 complex. Here we show that the matrix protein Mzm1 functions as a Rip1 chaperone, stabilizing Rip1 prior to the translocation step. In the absence of Mzm1, Rip1 is prone to either proteolytic degradation or temperature-induced aggregation. A series of Rip1 truncations were ...


Substrate Channeling In Proline Metabolism, Benjamin W. Arentson, Nikhilesh Sanyal, Donald F. Becker Jan 2012

Substrate Channeling In Proline Metabolism, Benjamin W. Arentson, Nikhilesh Sanyal, Donald F. Becker

Biochemistry -- Faculty Publications

Proline metabolism is an important pathway that has relevance in several cellular functions such as redox balance, apoptosis, and cell survival. Results from different groups have indicated that substrate channeling of proline metabolic intermediates may be a critical mechanism. One intermediate is pyrroline-5-carboxylate (P5C), which upon hydrolysis opens to glutamic semialdehyde (GSA). Recent structural and kinetic evidence indicate substrate channeling of P5C/ GSA occurs in the proline catabolic pathway between the proline dehydrogenase and P5C dehydrogenase active sites of bifunctional proline utilization A (PutA). Substrate channeling in PutA is proposed to facilitate the hydrolysis of P5C to GSA which is ...


Glutaredoxin 1 Protects Dopaminergic Cells By Increased Protein Glutathionylation In Experimental Parkinson's Disease, Humberto Rodriguez-Rocha, Aracely Garcia Garcia, Laura Zavala-Flores, Sumin Li, Nandakumar Madayiputhiya, Rodrigo Franco Jan 2012

Glutaredoxin 1 Protects Dopaminergic Cells By Increased Protein Glutathionylation In Experimental Parkinson's Disease, Humberto Rodriguez-Rocha, Aracely Garcia Garcia, Laura Zavala-Flores, Sumin Li, Nandakumar Madayiputhiya, Rodrigo Franco

Biochemistry -- Faculty Publications

Aims: Chronic exposure to environmental toxicants, such as paraquat, has been suggested as a risk factor for Parkinson's disease (PD). Although dopaminergic cell death in PD is associated with oxidative damage, the molecular mechanisms involved remain elusive. Glutaredoxins (GRXs) utilize the reducing power of glutathione to modulate redox-dependent signaling pathways by protein glutathionylation. We aimed to determine the role of GRX1 and protein glutathionylation in dopaminergic cell death. Results: In dopaminergic cells, toxicity induced by paraquat or 6-hydroxydopamine (6-OHDA) was inhibited by GRX1 overexpression, while its knock-down sensitized cells to paraquat-induced cell death. Dopaminergic cell death was paralleled by ...