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Expression Of A Low Co2-Inducible Protein, Lci1, Increases Inorganic Carbon Uptake In The Green Alga Chlamydomonas Reinhardtii, Norikazu Ohnishi, Hideya Fukuzawa, Bratati Mukherjee, Tomoki Tsujikawa, Mari Yanase, Hirobumi Nakano, James V. Moroney Sep 2010

Expression Of A Low Co2-Inducible Protein, Lci1, Increases Inorganic Carbon Uptake In The Green Alga Chlamydomonas Reinhardtii, Norikazu Ohnishi, Hideya Fukuzawa, Bratati Mukherjee, Tomoki Tsujikawa, Mari Yanase, Hirobumi Nakano, James V. Moroney

Faculty Publications

Aquatic photosynthetic organisms can modulate their photosynthesis to acclimate to CO2-limiting stress by inducing a carbon-concentrating mechanism (CCM) that includes carbonic anhydrases and inorganic carbon (Ci) transporters. However, to date, Ci-specific transporters have not been well characterized in eukaryotic algae. Previously, a Chlamydomonas reinhardtii mutant (lcr1) was identified that was missing a Myb transcription factor. This mutant had reduced light-dependent CO2 gas exchange (LCE) activity when grown under CO2-limiting conditions and did not induce the CAH1 gene encoding a periplasmic carbonic anhydrase, as well as two as yet uncharacterized genes, LCI1 and LCI6. In this study, LCI1 was placed under …

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Stabilization Of A Chemostat Model With Haldane Growth Functions And A Delay In The Measurements, Frédéric Mazenc, Michael Malisoff Sep 2010

Stabilization Of A Chemostat Model With Haldane Growth Functions And A Delay In The Measurements, Frédéric Mazenc, Michael Malisoff

Faculty Publications

The stabilization of equilibria in chemostats with measurement delays is a complex and challenging problem, and is of significant ongoing interest in bioengineering and population dynamics. In this paper, we solve an output feedback stabilization problem for chemostat models having two species, one limiting substrate, and either Haldane or Monod growth functions. Our feedback stabilizers depend on a given linear combination of the species concentrations, which are both measured with a constant time delay. The values of the delays are unknown. Instead, one only knows an upper bound on the delays, and we allow the upper bound to be arbitrarily …

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Delineation Of Differential Temporal Relations Between Specific Eating And Anxiety Disorders, Julia D. Buckner, Jose Silgado, Peter M. Lewinsohn Sep 2010

Delineation Of Differential Temporal Relations Between Specific Eating And Anxiety Disorders, Julia D. Buckner, Jose Silgado, Peter M. Lewinsohn

Faculty Publications

This study examined the temporal sequencing of eating and anxiety disorders to delineate which anxiety disorders increase eating disorder risk and whether individuals with eating disorders are at greater risk for particular anxiety disorders. The sample was drawn from the Oregon Adolescent Depression Project. Temporal relations between specific eating and anxiety disorders were examined after controlling for relevant variables (e.g., mood disorders, other anxiety disorders) over 14. years. After excluding those with anorexia nervosa (AN) in adolescence (T1), OCD was the only T1 anxiety disorder to predict AN by age 30 (T4). No T1 anxiety disorder was associated with T4 …

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The Impact Of Racial Metric Variation In The Os Coxae On The Morphological Assessment Of Sex, Ginesse A. Listi Sep 2010

The Impact Of Racial Metric Variation In The Os Coxae On The Morphological Assessment Of Sex, Ginesse A. Listi

Faculty Publications

This study examines whether sex determination based on morphological traits in the os coxae is impacted by racial quantitative variation. Nineteen traits were evaluated independently by two observers in 876 os coxae. Chi-square test was used on a random sample of 400 individuals to assess whether the distribution of correct sex assessment varied for white and black individuals based on each trait individually and all 19 traits collectively, as well as on inter-observer agreement in correct sex assessment. Results indicate that accuracy of sex assessment varied between white and black individuals in certain individual traits; however, accuracy was not impacted …

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Electrochemical Patterning Of Organic Monolayers On Silicon, Sri Sai S. Vegunta, Johnpeter N. Ngunjiri, John C. Flake Aug 2010

Electrochemical Patterning Of Organic Monolayers On Silicon, Sri Sai S. Vegunta, Johnpeter N. Ngunjiri, John C. Flake

Faculty Publications

Organic monolayers may be grafted onto silicon surfaces using an in situ electrochemical patterning method. In this technique, dielectric templates such as polystyrene spheres (ε=2.5) or poly(dimethylsiloxane) stamps (ε=2.3-2.8) are placed in close proximity to, or in direct contact with, silicon electrodes while a potential is applied to drive electrografting reactions. In this work, the authors describe methyl monolayer patterns created in anodic processes and phenylacetylene monolayer patterns created in cathodic processes. Both anodic and cathodic processes show similar chronoamperometric behavior, suggesting silicon passivation associated with the formation of monolayers. Atomic force microscopy shows the sizes, geometries, and thickness of …

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Targeted Interactomics Reveals A Complex Core Cell Cycle Machinery In Arabidopsis Thaliana, Jelle Van Leene, Jens Hollunder, Dominique Eeckhout, Geert Persiau, Eveline Van De Slijke, Hilde Stals, Gert Van Isterdael, Aurine Verkest, Sandy Neirynck, Yelle Buffel, Stefanie De Bodt, Steven Maere, Kris Laukens, Anne Pharazyn, Paulo C.G. Ferreira, Nubia Eloy, Charlotte Renne, Christian Meyer, Jean Denis Faure, Jens Steinbrenner, Jim Beynon, John C. Larkin, Yves Van De Peer, Pierre Hilson, Martin Kuiper, Lieven De Veylder, Harry Van Onckelen, Dirk Inzé, Erwin Witters, Geert De Jaeger Aug 2010

Targeted Interactomics Reveals A Complex Core Cell Cycle Machinery In Arabidopsis Thaliana, Jelle Van Leene, Jens Hollunder, Dominique Eeckhout, Geert Persiau, Eveline Van De Slijke, Hilde Stals, Gert Van Isterdael, Aurine Verkest, Sandy Neirynck, Yelle Buffel, Stefanie De Bodt, Steven Maere, Kris Laukens, Anne Pharazyn, Paulo C.G. Ferreira, Nubia Eloy, Charlotte Renne, Christian Meyer, Jean Denis Faure, Jens Steinbrenner, Jim Beynon, John C. Larkin, Yves Van De Peer, Pierre Hilson, Martin Kuiper, Lieven De Veylder, Harry Van Onckelen, Dirk Inzé, Erwin Witters, Geert De Jaeger

Faculty Publications

Cell proliferation is the main driving force for plant growth. Although genome sequence analysis revealed a high number of cell cycle genes in plants, little is known about the molecular complexes steering cell division. In a targeted proteomics approach, we mapped the core complex machinery at the heart of the Arabidopsis thaliana cell cycle control. Besides a central regulatory network of core complexes, we distinguished a peripheral network that links the core machinery to up- and downstream pathways. Over 100 new candidate cell cycle proteins were predicted and an in-depth biological interpretation demonstrated the hypothesis-generating power of the interaction data. …

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Location, Location, Location: Compartmentalization Of Early Events In Leukotriene Biosynthesis, Marcia E. Newcomer, Nathaniel C. Gilbert Aug 2010

Location, Location, Location: Compartmentalization Of Early Events In Leukotriene Biosynthesis, Marcia E. Newcomer, Nathaniel C. Gilbert

Faculty Publications

Leukotrienes (LTs), derived from arachidonic acid (AA) released from the membrane by the action of phospholipase A2, are potent lipid mediators of the inflammatory response. In 1983, Dahlén et al. demonstrated that LTC4, LTD4, and LTE4 mediate antigen-induced constriction of bronchi in tissue obtained from subjects with asthma (Dahlén, S. E., Hansson, G., Hedqvist, P., Björck, T., Granström, E., and Dahlén, B. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 1712-1716). Over the last 25+ years, substantial progress has been made in understanding how LTs exert their effects, and a broader appreciation for the numerous biological processes they mediate has emerged. …

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Kinetic And Spectroscopic Studies Of Hemin Acquisition In The Hemophore Hasap From Pseudomonas Aeruginosa, Erik T. Yukl, Grace Jepkorir, Aileen Y. Alontaga, Lawrence Pautsch, Juan C. Rodriguez, Mario Rivera, Pierre Moënne-Loccoz Aug 2010

Kinetic And Spectroscopic Studies Of Hemin Acquisition In The Hemophore Hasap From Pseudomonas Aeruginosa, Erik T. Yukl, Grace Jepkorir, Aileen Y. Alontaga, Lawrence Pautsch, Juan C. Rodriguez, Mario Rivera, Pierre Moënne-Loccoz

Faculty Publications

The extreme limitation of free iron has driven various pathogens to acquire iron from the host in the form of heme. Specifically, several Gram-negative pathogens secrete a heme binding protein known as HasA to scavenge heme from the extracellular environment and to transfer it to the receptor protein HasR for import into the bacterial cell. Structures of heme-bound and apo-HasA homologues show that the heme iron(III) ligands, His32 and Tyr75, reside on loops extending from the core of the protein and that a significant conformational change must occur at the His32 loop upon heme binding. Here, we investigate the kinetics …

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Titer-Plate Formatted Continuous Flow Thermal Reactors: Design And Performance Of A Nanoliter Reactor, Pin Chuan Chen, Daniel S. Park, Byoung Hee You, Namwon Kim, Taehyun Park, Steven A. Soper, Dimitris E. Nikitopoulos, Michael C. Murphy Aug 2010

Titer-Plate Formatted Continuous Flow Thermal Reactors: Design And Performance Of A Nanoliter Reactor, Pin Chuan Chen, Daniel S. Park, Byoung Hee You, Namwon Kim, Taehyun Park, Steven A. Soper, Dimitris E. Nikitopoulos, Michael C. Murphy

Faculty Publications

Arrays of continuous flow thermal reactors were designed, configured, and fabricated in a 96-device (12 × 8) titer-plate format with overall dimensions of 120 mm × 96 mm, with each reactor confined to a 8 mm × 8 mm footprint. To demonstrate the potential, individual 20-cycle (740 nl) and 25-cycle (990 nl) reactors were used to perform the continuous flow polymerase chain reaction (CFPCR) for amplification of DNA fragments of different lengths. Since thermal isolation of the required temperature zones was essential for optimal biochemical reactions, three finite element models, executed with ANSYS (v. 11.0, Canonsburg, PA), were used to …

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Insights Into Particle Formation And Remineralization Using The Short-Lived Radionuclide, Thoruim-234, Kanchan Maiti, Claudia R. Benitez-Nelson, Ken O. Buesseler Aug 2010

Insights Into Particle Formation And Remineralization Using The Short-Lived Radionuclide, Thoruim-234, Kanchan Maiti, Claudia R. Benitez-Nelson, Ken O. Buesseler

Faculty Publications

Simple mass balance models are applied to a high resolution 234Th profile from the northwest Pacific to examine the magnitude, rate, and depth distribution of particle remineralization processes below the euphotic zone (Ez). Here, excess 234Th (234Th > 238U) below the Ez is attributed to fragmentation processes that result in the conversion of sinking to non-sinking particles. By considering particulate organic carbon (POC) to 234Th ratios on particles, we show that POC flux attenuation is larger than for 234Th, which we attribute to bacterial and zooplankton consumption of sinking POC. Three case studies are …

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Phase-Response Curves And Synchronized Neural Networks., Smeal Rm, Ermentrout Gb, White Ja Aug 2010

Phase-Response Curves And Synchronized Neural Networks., Smeal Rm, Ermentrout Gb, White Ja

Faculty Publications

No abstract provided.

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Increased Lipid Accumulation In The Chlamydomonas Reinhardtii Sta7-10 Starchless Isoamylase Mutant And Increased Carbohydrate Synthesis In Complemented Strains, Victoria H. Work, Randor Radakovits, Robert E. Jinkerson, Jonathan E. Meuser, Lee G. Elliott, David J. Vinyard, Lieve M.L. Laurens, G. Charles Dismukes, Matthew C. Posewitz Aug 2010

Increased Lipid Accumulation In The Chlamydomonas Reinhardtii Sta7-10 Starchless Isoamylase Mutant And Increased Carbohydrate Synthesis In Complemented Strains, Victoria H. Work, Randor Radakovits, Robert E. Jinkerson, Jonathan E. Meuser, Lee G. Elliott, David J. Vinyard, Lieve M.L. Laurens, G. Charles Dismukes, Matthew C. Posewitz

Faculty Publications

The accumulation of bioenergy carriers was assessed in two starchless mutants of Chlamydomonas reinhardtii (the sta6 [ADP-glucose pyrophosphorylase] and sta7-10 [isoamylase] mutants), a control strain (CC124), and two complemented strains of the sta7-10 mutant. The results indicate that the genetic blockage of starch synthesis in the sta6 and sta7-10 mutants increases the accumulation of lipids on a cellular basis during nitrogen deprivation relative to that in the CC124 control as determined by conversion to fatty acid methyl esters. However, this increased level of lipid accumulation is energetically insufficient to completely offset the loss of cellular starch that is synthesized by …

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Effect Of Overall Charge And Charge Distribution On Cellular Uptake, Distribution And Phototoxicity Of Cationic Porphyrins In Hep2 Cells, Timothy J. Jensen, M. Graça H. Vicente, Raymond Luguya, Jolanna Norton, Frank R. Fronczek, Kevin M. Smith Aug 2010

Effect Of Overall Charge And Charge Distribution On Cellular Uptake, Distribution And Phototoxicity Of Cationic Porphyrins In Hep2 Cells, Timothy J. Jensen, M. Graça H. Vicente, Raymond Luguya, Jolanna Norton, Frank R. Fronczek, Kevin M. Smith

Faculty Publications

Five cationic porphyrins bearing one to four -N(CH3)3+ groups linked to the p-phenyl positions of 5,10,15,20-tetraphenylporphyrin (TPP) were synthesized in order to study the effect of overall charge and its distribution on the cellular uptake, phototoxicity and intracellular localization using human carcinoma HEp2 cells. The di-cationic porphyrins DADP-o and DADP-a accumulated the most within cells and preferentially localize within vesicular compartments and in mitochondria. Of these two only DADP-a was phototoxic to the cells (IC50=3μM at 1J/cm2). The mono-cationic porphyrin MAP was found to be the most phototoxic of the series, and it localized mainly in lipid membranes, including the …

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A Comparative Study Of Salt Tolerance Parameters In 11 Wild Relatives Of Arabidopsis Thaliana, Francesco Orsini, Matilde Paino D'Urzo, Gunsu Inan, Sara Serra, Dong Ha Oh, Michael V. Mickelbart, Federica Consiglio, Xia Li, Jae Cheol Jeong, Dae Jin Yun, Hans J. Bohnert, Ray A. Bressan, Albino Maggio Aug 2010

A Comparative Study Of Salt Tolerance Parameters In 11 Wild Relatives Of Arabidopsis Thaliana, Francesco Orsini, Matilde Paino D'Urzo, Gunsu Inan, Sara Serra, Dong Ha Oh, Michael V. Mickelbart, Federica Consiglio, Xia Li, Jae Cheol Jeong, Dae Jin Yun, Hans J. Bohnert, Ray A. Bressan, Albino Maggio

Faculty Publications

Salinity is an abiotic stress that limits both yield and the expansion of agricultural crops to new areas. In the last 20 years our basic understanding of the mechanisms underlying plant tolerance and adaptation to saline environments has greatly improved owing to active development of advanced tools in molecular, genomics, and bioinformatics analyses. However, the full potential of investigative power has not been fully exploited, because the use of halophytes as model systems in plant salt tolerance research is largely neglected. The recent introduction of halophytic Arabidopsis-Relative Model Species (ARMS) has begun to compare and relate several unique genetic resources …

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Metabolic Preconditioning Of Cells With Aicar-Riboside: Improved Cryopreservation And Cell-Type Specific Impacts On Energetics And Proliferation, Michael A. Menze, Nilay Chakraborty, Matthew Clavenna, Mitali Banerjee, Xiang Hong Liu, Mehmet Toner, Steven C. Hand Aug 2010

Metabolic Preconditioning Of Cells With Aicar-Riboside: Improved Cryopreservation And Cell-Type Specific Impacts On Energetics And Proliferation, Michael A. Menze, Nilay Chakraborty, Matthew Clavenna, Mitali Banerjee, Xiang Hong Liu, Mehmet Toner, Steven C. Hand

Faculty Publications

In species whose evolutionary history has provided natural tolerance to dehydration and freezing, metabolic depression is often a pre-requisite for survival. We tested the hypothesis that preconditioning of mammalian cells with 5-aminoimidazole-4-carboxamide-1-b-d-ribofuranoside (AICAR) to achieve metabolic depression will promote greater survivorship during cryopreservation. AICAR is used extensively to stimulate AMP-activated protein kinase (AMPK), which can result in downregulation of biosynthetic processes. We showed that the metabolic interconversion of AICAR was cell-type dependent. Accumulation of 5-aminoimidazole-4-carboxamide-1b-d-ribofuranosyl-5'-monophosphate (ZMP), as well as other metabolites that possess multiple phosphates (i.e., ZDP, ZTP), varied approximately 3.5-fold across the cell lines tested. AICAR treatment also significantly …

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A Mobile Threat To Genome Stability: The Impact Of Non-Ltr Retrotransposons Upon The Human Genome, Miriam K. Konkel, Mark A. Batzer Aug 2010

A Mobile Threat To Genome Stability: The Impact Of Non-Ltr Retrotransposons Upon The Human Genome, Miriam K. Konkel, Mark A. Batzer

Faculty Publications

It is now commonly agreed that the human genome is not the stable entity originally presumed. Deletions, duplications, inversions, and insertions are common, and contribute significantly to genomic structural variations (SVs). Their collective impact generates much of the inter-individual genomic diversity observed among humans. Not only do these variations change the structure of the genome; they may also have functional implications, e.g. altered gene expression. Some SVs have been identified as the cause of genetic disorders, including cancer predisposition. Cancer cells are notorious for their genomic instability, and often show genomic rearrangements at the microscopic and submicroscopic level to which …

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Cryptotanshinone Inhibits Cancer Cell Proliferation By Suppressing Mammalian Target Of Rapamycin - Mediated Cyclin D1 Expression And Rb Phosphorylation, Wenxing Chen, Yan Luo, Lei Liu, Hongyu Zhou, Baoshan Xu, Xiuzhen Han, Tao Shen, Zhijun Liu, Yin Lu, Shile Huang Aug 2010

Cryptotanshinone Inhibits Cancer Cell Proliferation By Suppressing Mammalian Target Of Rapamycin - Mediated Cyclin D1 Expression And Rb Phosphorylation, Wenxing Chen, Yan Luo, Lei Liu, Hongyu Zhou, Baoshan Xu, Xiuzhen Han, Tao Shen, Zhijun Liu, Yin Lu, Shile Huang

Faculty Publications

Cryptotanshinone (CPT), a natural compound isolated from the plant Salvia miltiorrhiza Bunge, is a potential anticancer agent. However, little is known about its anticancer mechanism. Here, we show that CPT inhibited cancer cell proliferation by arresting cells in G1-G0 phase of the cell cycle. This is associated with the inhibition of cyclin D1 expression and retinoblastoma (Rb) protein phosphorylation. Furthermore, we found that CPT inhibited the signaling pathway of the mammalian target of rapamycin (mTOR), a central regulator of cell proliferation. This is evidenced by the findings that CPT inhibited type I insulin-like growth factor I- or 10% fetal bovine …

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Obesity Increases The Production Of Proinflammatory Mediators From Adipose Tissue T Cells And Compromises Tcr Repertoire Diversity: Implications For Systemic Inflammation And Insulin Resistance, Hyunwon Yang, Yun Hee Youm, Bolormaa Vandanmagsar, Anthony Ravussin, Jeffrey M. Gimble, Frank Greenway, Jacqueline M. Stephens, Randall L. Mynatt, Vishwa Deep Dixit Aug 2010

Obesity Increases The Production Of Proinflammatory Mediators From Adipose Tissue T Cells And Compromises Tcr Repertoire Diversity: Implications For Systemic Inflammation And Insulin Resistance, Hyunwon Yang, Yun Hee Youm, Bolormaa Vandanmagsar, Anthony Ravussin, Jeffrey M. Gimble, Frank Greenway, Jacqueline M. Stephens, Randall L. Mynatt, Vishwa Deep Dixit

Faculty Publications

Emerging evidence suggests that increases in activated T cell populations in adipose tissue may contribute toward obesity-associated metabolic syndrome. The present study investigates three unanswered questions: 1) Do adipose-resident T cells (ARTs) from lean and obese mice have altered cytokine production in response to TCR ligation?; 2) Do the extralymphoid ARTs possess a unique TCR repertoire compared with lymphoid-resident T cells and whether obesity alters the TCR diversity in specific adipose depots?; and 3) Does short-term elimination of T cells in epididymal fat pad without disturbing the systemic T cell homeostasis regulate inflammation and insulin-action during obesity? We found that …

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Cenozoic Mud Volcano Activity Along The Indus Fan: Offshore Pakistan, G. Calvès, A. M. Schwab, M. Huuse, P. Van Rensbergen, P. D. Clift, A. R. Tabrez, A. Inam Aug 2010

Cenozoic Mud Volcano Activity Along The Indus Fan: Offshore Pakistan, G. Calvès, A. M. Schwab, M. Huuse, P. Van Rensbergen, P. D. Clift, A. R. Tabrez, A. Inam

Faculty Publications

This study documents the tectono-stratigraphic setting and expulsion history of a major, previously undescribed mud volcano (MV) province in the Indus Submarine Fan, offshore Pakistan. A buried MV field of nine composite MVs has been recognized using two-dimensional (2D) and 3D seismic reflection data in a confined area of 50 × 65 km2. Conduits are recognized on each of these MVs connecting the pre-Eocene parent beds to the stacked mud cones. The buried MVs are up to 8.4 km wide (4.5 km average) with a central conduit of 1.23 km average diameter and an average mud cone thickness of 0.33 …

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Genetic Evidence For High Propagule Pressure And Long-Distance Dispersal In Monk Parakeet (Myiopsitta Monachus) Invasive Populations, Anders Gonçalves Da Silva, Jessica R. Eberhard, Timothy F. Wright, Michael L. Avery, Michael A. Russello Aug 2010

Genetic Evidence For High Propagule Pressure And Long-Distance Dispersal In Monk Parakeet (Myiopsitta Monachus) Invasive Populations, Anders Gonçalves Da Silva, Jessica R. Eberhard, Timothy F. Wright, Michael L. Avery, Michael A. Russello

Faculty Publications

The monk parakeet (Myiopsitta monachus) is a successful invasive species that does not exhibit life history traits typically associated with colonizing species (e.g., high reproductive rate or long-distance dispersal capacity). To investigate this apparent paradox, we examined individual and population genetic patterns of microsatellite loci at one native and two invasive sites. More specifically, we aimed at evaluating the role of propagule pressure, sexual monogamy and long-distance dispersal in monk parakeet invasion success. Our results indicate little loss of genetic variation at invasive sites relative to the native site. We also found strong evidence for sexual monogamy from patterns of …

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Structural, Nmr Spectroscopic, And Computational Investigation Of Hemin Loading In The Hemophore Hasap From Pseudomonas Aeruginosa, Grace Jepkorir, Juan Carlos Rodríguez, Huan Rui, Wonpil Im, Scott Lovell, Kevin P. Battaile, Aileen Y. Alontaga, Erik T. Yukl, Pierre Moënne-Loccoz, Mario Rivera Jul 2010

Structural, Nmr Spectroscopic, And Computational Investigation Of Hemin Loading In The Hemophore Hasap From Pseudomonas Aeruginosa, Grace Jepkorir, Juan Carlos Rodríguez, Huan Rui, Wonpil Im, Scott Lovell, Kevin P. Battaile, Aileen Y. Alontaga, Erik T. Yukl, Pierre Moënne-Loccoz, Mario Rivera

Faculty Publications

When challenged by low-iron conditions several Gram-negative pathogens secrete a hemophore (HasA) to scavenge hemin from its host and deliver it to a receptor (HasR) on their outer membrane for internalization. Here we report results from studies aimed at probing the structural and dynamic processes at play in the loading of the apo-hemophore secreted by P. aeruginosa (apo-HasAp) with hemin. The structure of apo-HasAp shows a large conformational change in the loop harboring axial ligand His32 relative to the structure of holo-HasAp, whereas the loop bearing the other axial ligand, Tyr75, remains intact. To investigate the role played by the …

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A New Lysozyme From The Eastern Oyster, Crassostrea Virginica, And A Possible Evolutionary Pathway For I-Type Lysozymes In Bivalves From Host Defense To Digestion, Qinggang Xue, Michael E. Hellberg, Kevin L. Schey, Naoki Itoh, Ron I. Eytan, Richard K. Cooper, Jerome F. La Peyre Jul 2010

A New Lysozyme From The Eastern Oyster, Crassostrea Virginica, And A Possible Evolutionary Pathway For I-Type Lysozymes In Bivalves From Host Defense To Digestion, Qinggang Xue, Michael E. Hellberg, Kevin L. Schey, Naoki Itoh, Ron I. Eytan, Richard K. Cooper, Jerome F. La Peyre

Faculty Publications

Background. Lysozymes are enzymes that lyse bacterial cell walls, an activity widely used for host defense but also modified in some instances for digestion. The biochemical and evolutionary changes between these different functional forms has been well-studied in the c-type lysozymes of vertebrates, but less so in the i-type lysozymes prevalent in most invertebrate animals. Some bivalve molluscs possess both defensive and digestive lysozymes. Results. We report a third lysozyme from the oyster Crassostrea virginica, cv-lysozyme 3. The chemical properties of cv-lysozyme 3 (including molecular weight, isoelectric point, basic amino acid residue number, and predicted protease cutting sites) suggest it …

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A New Lysozyme From The Eastern Oyster, Crassostrea Virginica, And A Possible Evolutionary Pathway For I-Type Lysozymes In Bivalves From Host Defense To Digestion, Qinggang Xue, Michael E. Hellberg, Kevin L. Schey, Naoki Itoh, Ron I. Eytan, Richard K. Cooper, Jerome F. La Peyre Jul 2010

A New Lysozyme From The Eastern Oyster, Crassostrea Virginica, And A Possible Evolutionary Pathway For I-Type Lysozymes In Bivalves From Host Defense To Digestion, Qinggang Xue, Michael E. Hellberg, Kevin L. Schey, Naoki Itoh, Ron I. Eytan, Richard K. Cooper, Jerome F. La Peyre

Faculty Publications

Background. Lysozymes are enzymes that lyse bacterial cell walls, an activity widely used for host defense but also modified in some instances for digestion. The biochemical and evolutionary changes between these different functional forms has been well-studied in the c-type lysozymes of vertebrates, but less so in the i-type lysozymes prevalent in most invertebrate animals. Some bivalve molluscs possess both defensive and digestive lysozymes. Results. We report a third lysozyme from the oyster Crassostrea virginica, cv-lysozyme 3. The chemical properties of cv-lysozyme 3 (including molecular weight, isoelectric point, basic amino acid residue number, and predicted protease cutting sites) suggest it …

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A New Lysozyme From The Eastern Oyster, Crassostrea Virginica, And A Possible Evolutionary Pathway For I-Type Lysozymes In Bivalves From Host Defense To Digestion, Qinggang Xue, Michael E. Hellberg, Kevin L. Schey, Naoki Itoh, Ron I. Eytan, Richard K. Cooper, Jerome F. La Peyre Jul 2010

A New Lysozyme From The Eastern Oyster, Crassostrea Virginica, And A Possible Evolutionary Pathway For I-Type Lysozymes In Bivalves From Host Defense To Digestion, Qinggang Xue, Michael E. Hellberg, Kevin L. Schey, Naoki Itoh, Ron I. Eytan, Richard K. Cooper, Jerome F. La Peyre

Faculty Publications

Background. Lysozymes are enzymes that lyse bacterial cell walls, an activity widely used for host defense but also modified in some instances for digestion. The biochemical and evolutionary changes between these different functional forms has been well-studied in the c-type lysozymes of vertebrates, but less so in the i-type lysozymes prevalent in most invertebrate animals. Some bivalve molluscs possess both defensive and digestive lysozymes. Results. We report a third lysozyme from the oyster Crassostrea virginica, cv-lysozyme 3. The chemical properties of cv-lysozyme 3 (including molecular weight, isoelectric point, basic amino acid residue number, and predicted protease cutting sites) suggest it …

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Oxygen Is Required For The L-Cysteine-Mediated Decomposition Of Protein-Bound Dinitrosyl-Iron Complexes, Juanjuan Yang, Xuewu Duan, Aaron P. Landry, Huangen Ding Jul 2010

Oxygen Is Required For The L-Cysteine-Mediated Decomposition Of Protein-Bound Dinitrosyl-Iron Complexes, Juanjuan Yang, Xuewu Duan, Aaron P. Landry, Huangen Ding

Faculty Publications

Increasing evidence suggests that iron-sulfur proteins are the primary targets of nitric oxide (NO). Exposure of Escherichia coli cells to NO readily converts iron-sulfur proteins to protein-bound dinitrosyl-iron complexes (DNICs). Although the protein-bound DNICs are stable in vitro under aerobic or anaerobic conditions, they are efficiently repaired in aerobically growing E. coli cells even without new protein synthesis. The cellular repair mechanism for the NO-modified iron-sulfur proteins remains largely elusive. Here we report that, unlike aerobically growing E. coli cells, starved E. coli cells fail to reactivate the NO-modified iron-sulfur proteins. Significantly, the addition of l-cysteine, but not other related …

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Pangea: Pipeline For Analysis Of Next Generation Amplicons, Adriana Giongo, David B. Crabb, Austin G. Davis-Richardson, Diane Chauliac, Jennifer M. Mobberley, Kelsey A. Gano, Nabanita Mukherjee, George Casella, Luiz F.W. Roesch, Brandon Walts, Alberto Riva, Gary King, Eric W. Triplett Jul 2010

Pangea: Pipeline For Analysis Of Next Generation Amplicons, Adriana Giongo, David B. Crabb, Austin G. Davis-Richardson, Diane Chauliac, Jennifer M. Mobberley, Kelsey A. Gano, Nabanita Mukherjee, George Casella, Luiz F.W. Roesch, Brandon Walts, Alberto Riva, Gary King, Eric W. Triplett

Faculty Publications

High-throughput DNA sequencing can identify organisms and describe population structures in many environmental and clinical samples. Current technologies generate millions of reads in a single run, requiring extensive computational strategies to organize, analyze and interpret those sequences. A series of bioinformatics tools for high-throughput sequencing analysis, including pre-processing, clustering, database matching and classification, have been compiled into a pipeline called PANGEA. The PANGEA pipeline was written in Perl and can be run on Mac OSX, Windows or Linux. With PANGEA, sequences obtained directly from the sequencer can be processed quickly to provide the files needed for sequence identification by BLAST …

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Behavioral And Physiological Plasticity: Rapid Changes During Social Ascent In An African Cichlid Fish, Karen P. Maruska, Russell D. Fernald Jul 2010

Behavioral And Physiological Plasticity: Rapid Changes During Social Ascent In An African Cichlid Fish, Karen P. Maruska, Russell D. Fernald

Faculty Publications

In many vertebrates, reproduction is regulated by social interactions in which dominant males control access to females and food. Subordinate males that displace dominant individuals must rapidly adopt behavioral and physiological traits of the higher rank to gain reproductive success. To understand the process of phenotypic plasticity during social ascent, we analyzed the temporal expression pattern of dominance behaviors and circulating androgen levels when socially-suppressed males of an African cichlid fish Astatotilapia burtoni ascended in status. These experiments tested a prediction of the 'challenge hypothesis' that, during periods of social instability, male androgen levels are higher than during socially stable …

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Laboratory Evaluation Of The Efficacy Of Fluorescent Biomarkers For Sugar-Feeding Sand Flies (Diptera: Psychodidae), T. M. Mascari, L. D. Foil Jul 2010

Laboratory Evaluation Of The Efficacy Of Fluorescent Biomarkers For Sugar-Feeding Sand Flies (Diptera: Psychodidae), T. M. Mascari, L. D. Foil

Faculty Publications

The purpose of this study was to evaluate the use of four fluorescent dyes (rhodamine B, uranine O, auramine O, and erythrosin B) and two nonfluorescent dyes (carmoisine and indigotine) incorporated into sugar baits as biomarkers for phlebotomine sand flies, Each dye could be detected in sand flies fed baits with dye for 24 h when examined using bright field microscopy, although there was considerable variability in the marking produced; all sand flies that had ingested rhodamine B-treated sucrose solution were marked clearly. Sand flies that had ingested sucrose solution containing rhodamine B or uranine O at concentrations as low …

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Rapid Identification Of Oil-Contaminated Soils Using Visible Near-Infrared Diffuse Reflectance Spectroscopy, Somsubhra Chakraborty, David C. Weindorf, Cristine L.S. Morgan, Yufeng Ge, John M. Galbraith, Bin Li, Charanjit S. Kahlon Jul 2010

Rapid Identification Of Oil-Contaminated Soils Using Visible Near-Infrared Diffuse Reflectance Spectroscopy, Somsubhra Chakraborty, David C. Weindorf, Cristine L.S. Morgan, Yufeng Ge, John M. Galbraith, Bin Li, Charanjit S. Kahlon

Faculty Publications

In the United States, petroleum extraction, refinement, and transportation present countless opportunities for spillage mishaps. A method for rapid field appraisal and mapping of petroleum hydrocarbon-contaminated soils for environmental cleanup purposes would be useful. Visible near-infrared (VisNIR, 350-2500 nm) diffuse reflectance spectroscopy (DRS) is a rapid, nondestructive, proximal-sensing technique that has proven adept at quantifying soil properties in situ. The objective of this study was to determine the prediction accuracy of VisNIR DRS in quantifying petroleum hydrocarbons in contaminated soils. Forty-six soil samples (including both contaminated and reference samples) were collected from six different parishes in Louisiana. Each soil sample …

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Host Behaviour And Exposure Risk In An Insect-Pathogen Interaction, Benjamin J. Parker, Bret D. Elderd, Greg Dwyer Jul 2010

Host Behaviour And Exposure Risk In An Insect-Pathogen Interaction, Benjamin J. Parker, Bret D. Elderd, Greg Dwyer

Faculty Publications

1. Studies of variability in host resistance to disease generally emphasize variability in susceptibility given exposure, neglecting the possibility that hosts may vary in behaviours that affect the risk of exposure. 2. In many insects, horizontal transmission of baculoviruses occurs when larvae consume foliage contaminated by the cadavers of virus-infected conspecific larvae; so, host behaviour may have a strong effect on the risk of infection. 3. We studied variability in the behaviour of gypsy moth (Lymantria dispar) larvae, which are able to detect and avoid virus-contaminated foliage. 4. Our results show that detection ability can be affected by the family …

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