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Bionic Architectural Design: Assembly, Symbiosis, & Repetition, Henry Louth May 2007

Bionic Architectural Design: Assembly, Symbiosis, & Repetition, Henry Louth

Honors Capstones

No abstract provided.


Video Game Addiction: Truth Or Fiction, Lyles Thibodeaux-Harmony May 2007

Video Game Addiction: Truth Or Fiction, Lyles Thibodeaux-Harmony

Honors Capstones

No abstract provided.


Bacteria Homolog Of Frataxin, Cyay, And Its Role In The Interaction With The Isc System, Simon Yeung May 2007

Bacteria Homolog Of Frataxin, Cyay, And Its Role In The Interaction With The Isc System, Simon Yeung

Honors Capstones

No abstract provided.


Tests Of The Extension And Deadbolt Models Of Integrin Activation, Jieqing Zhu, Brian Boylan, Bing Hao Luo, Peter J. Newman, Timothy A. Springer Apr 2007

Tests Of The Extension And Deadbolt Models Of Integrin Activation, Jieqing Zhu, Brian Boylan, Bing Hao Luo, Peter J. Newman, Timothy A. Springer

Faculty Publications

Despite extensive evidence that integrin conformational changes between bent and extended conformations regulate affinity for ligands, an alternative hypothesis has been proposed in which a "deadbolt" can regulate affinity for ligand in the absence of extension. Here, we tested both the deadbolt and the extension models. According to the deadbolt model, a hairpin loop in the β3 tail domain could act as a deadbolt to restrain the displacement of the β3 I domain β6-α7 loop and maintain integrin in the low affinity state. We found that mutating or deleting the β3 tail domain loop has no effect on ligand binding …


The N-Terminal Extensions Of Deinococcus Radiodurans Dps-1 Mediate Dna Major Groove Interactions As Well As Assembly Of The Dodecamer, Gargi Bhattacharyya, Anne Grove Apr 2007

The N-Terminal Extensions Of Deinococcus Radiodurans Dps-1 Mediate Dna Major Groove Interactions As Well As Assembly Of The Dodecamer, Gargi Bhattacharyya, Anne Grove

Faculty Publications

Dps (DNA protection during starvation) proteins play an important role in the protection of prokaryotic macromolecules from damage by reactive oxygen species. Previous studies have suggested that the lysine-rich N-terminal tail of Dps proteins participates in DNA binding. In comparison with other Dps proteins, Dps-1 from Deinococcus radiodurans has an extended N terminus comprising 55 amino acids preceding the first helix of the 4-helix bundle monomer. In the crystal structure of Dps-1, the first ∼30 N-terminal residues are invisible, and the remaining 25 residues form a loop that harbors a novel metal-binding site. We show here that deletion of the …


Mobile Dna In Old World Monkeys: A Glimpse Through The Rhesus Macaque Genome, Kyudong Han, Miriam K. Konkel, Jinchuan Xing, Hui Wang, Jungnam Lee, Thomas J. Meyer, Charles T. Huang, Erin Sandifer, Kristi Hebert, Erin W. Barnes, Robert Hubley, Webb Miller, Arian F.A. Smit, Brygg Ullmer, Mark A. Batzer Apr 2007

Mobile Dna In Old World Monkeys: A Glimpse Through The Rhesus Macaque Genome, Kyudong Han, Miriam K. Konkel, Jinchuan Xing, Hui Wang, Jungnam Lee, Thomas J. Meyer, Charles T. Huang, Erin Sandifer, Kristi Hebert, Erin W. Barnes, Robert Hubley, Webb Miller, Arian F.A. Smit, Brygg Ullmer, Mark A. Batzer

Faculty Publications

The completion of the draft sequence of the rhesus macaque genome allowed us to study the genomic composition and evolution of transposable elements in this representative of the Old World monkey lineage, a group of diverse primates closely related to humans. The L1 family of long interspersed elements appears to have evolved as a single lineage, and Alu elements have evolved into four currently active lineages. We also found evidence of elevated horizontal transmissions of retroviruses and the absence of DNA transposon activity in the Old World monkey lineage. In addition, ∼100 precursors of composite SVA (short interspersed element, variable …


Evolutionary And Biomedical Insights From The Rhesus Macaque Genome, Richard A. Gibbs, Jeffrey Rogers, Michael G. Katze, Roger Bumgarner, George M. Weinstock, Elaine R. Mardis, Karin A. Remington, Robert L. Strausberg, J. Craig Venter, Richard K. Wilson, Mark A. Batzer, Carlos D. Bustamante, Evan E. Eichler, Matthew W. Hahn, Ross C. Hardison, Kateryna D. Makova, Webb Miller, Aleksandar Milosavljevic, Robert E. Palermo, Adam Siepel, James M. Sikela, Tony Attaway, Stephanie Bell, Kelly E. Bernard, Christian J. Buhay, Mimi N. Chandrabose, Marvin Dao, Clay Davis, Kimberly D. Delehaunty, Yan Ding, Huyen H. Dinh, Shannon Dugan-Rocha, Lucinda A. Fulton, Ramatu Ayiesha Gabisi Apr 2007

Evolutionary And Biomedical Insights From The Rhesus Macaque Genome, Richard A. Gibbs, Jeffrey Rogers, Michael G. Katze, Roger Bumgarner, George M. Weinstock, Elaine R. Mardis, Karin A. Remington, Robert L. Strausberg, J. Craig Venter, Richard K. Wilson, Mark A. Batzer, Carlos D. Bustamante, Evan E. Eichler, Matthew W. Hahn, Ross C. Hardison, Kateryna D. Makova, Webb Miller, Aleksandar Milosavljevic, Robert E. Palermo, Adam Siepel, James M. Sikela, Tony Attaway, Stephanie Bell, Kelly E. Bernard, Christian J. Buhay, Mimi N. Chandrabose, Marvin Dao, Clay Davis, Kimberly D. Delehaunty, Yan Ding, Huyen H. Dinh, Shannon Dugan-Rocha, Lucinda A. Fulton, Ramatu Ayiesha Gabisi

Faculty Publications

The rhesus macaque (Macaca mulatta) is an abundant primate species that diverged from the ancestors of Homo sapiens about 25 million years ago. Because they are genetically and physiologically similar to humans, rhesus monkeys are the most widely used nonhuman primate in basic and applied biomedical research. We determined the genome sequence of an Indian-origin Macaca mulatta female and compared the data with chimpanzees and humans to reveal the structure of ancestral primate genomes and to identify evidence for positive selection and lineage-specific expansions and contractions of gene families. A comparison of sequences from individual animals was used to investigate …


Palmitoylation Of The Cysteine-Rich Endodomain Of The Sars-Coronavirus Spike Glycoprotein Is Important For Spike-Mediated Cell Fusion, Chad M. Petit, Vladimir N. Chouljenko, Arun Iyer, Robin Colgrove, Michael Farzan, David M. Knipe, K. G. Kousoulas Apr 2007

Palmitoylation Of The Cysteine-Rich Endodomain Of The Sars-Coronavirus Spike Glycoprotein Is Important For Spike-Mediated Cell Fusion, Chad M. Petit, Vladimir N. Chouljenko, Arun Iyer, Robin Colgrove, Michael Farzan, David M. Knipe, K. G. Kousoulas

Faculty Publications

The SARS-coronavirus (SARS-CoV) is the etiological agent of the severe acute respiratory syndrome (SARS). The SARS-CoV spike (S) glycoprotein mediates membrane fusion events during virus entry and virus-induced cell-to-cell fusion. The cytoplasmic portion of the S glycoprotein contains four cysteine-rich amino acid clusters. Individual cysteine clusters were altered via cysteine-to-alanine amino acid replacement and the modified S glycoproteins were tested for their transport to cell-surfaces and ability to cause cell fusion in transient transfection assays. Mutagenesis of the cysteine cluster I, located immediately proximal to the predicted transmembrane, domain did not appreciably reduce cell-surface expression, although S-mediated cell fusion was …


Disparate Distributions Of Chemolithotrophs Containing Form Ia Or Ic Large Subunit Genes For Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase In Intertidal Marine And Littoral Lake Sediments, Lisa M. Nigro, Gary M. King Apr 2007

Disparate Distributions Of Chemolithotrophs Containing Form Ia Or Ic Large Subunit Genes For Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase In Intertidal Marine And Littoral Lake Sediments, Lisa M. Nigro, Gary M. King

Faculty Publications

The distributions of bacterial form IA and form IC ribulose-1,5- bisphosphate carboxylase/oxygenase (RuBisCO) were investigated using Lowes Cove intertidal mudflat and Damariscotta Lake littoral sediments by PCR amplification of 492-495 bp fragments of the large subunit RuBisCO gene, cbbL. Genomic extracts for amplification were obtained from lake surface (upper 2 mm), mudflat surface (upper 2 mm), subsurface (5-7 cm), and soft-shell clam (Mya arenaria) burrow-wall sediments, as well as from a sulfide-oxidizing mat. Phylogenetic analyses of cbbL clone libraries revealed that Lowes Cove sediments were dominated by form IA cbbL-containing sequences most closely related to cbbL genes of sulfur-oxidizing bacteria …


Bayesian Change-Point Analyses In Ecology, Brian Beckage, Lawrence Joseph, Patrick Belisle, David B. Wolfson, William J. Platt Apr 2007

Bayesian Change-Point Analyses In Ecology, Brian Beckage, Lawrence Joseph, Patrick Belisle, David B. Wolfson, William J. Platt

Faculty Publications

• Ecological and biological processes can change from one state to another once a threshold has been crossed in space or time. Threshold responses to incremental changes in underlying variables can characterize diverse processes from climate change to the desertification of arid lands from overgrazing. • Simultaneously estimating the location of thresholds and associated ecological parameters can be difficult: ecological data are often 'noisy', which can make the identification of the locations of ecological thresholds challenging. • We illustrate this problem using two ecological examples and apply a class of statistical models well-suited to addressing this problem. We first consider …


Ancestral Alleles And Population Origins: Inferences Depend On Mutation Rate, Alan R. Rogers, Stephen Wooding, Chad D. Huff, Mark A. Batzer, Lynn B. Jorde Apr 2007

Ancestral Alleles And Population Origins: Inferences Depend On Mutation Rate, Alan R. Rogers, Stephen Wooding, Chad D. Huff, Mark A. Batzer, Lynn B. Jorde

Faculty Publications

Previous studies have found that at most human loci, ancestral alleles are "African," in the sense that they reach their highest frequency there. Conventional wisdom holds that this reflects a recent African origin of modern humans. This paper challenges that view by showing that the empirical pattern (of elevated allele frequencies within Africa) is not as pervasive as has been thought. We confirm this African bias in a set of mainly protein-coding loci, but find a smaller bias in Alu insertion polymorphisms, and an even smaller bias in noncoding loci. Thus, the strong bias that was originally observed must reflect …


Introduction For The Gene Special Issue Dedicated To The Meeting "Genomic Impact Of Eukaryotic Transposable Elements" At Asilomar, Mark A. Batzer, Prescott L. Deininger, Jerzy Jurka, John V. Moran Apr 2007

Introduction For The Gene Special Issue Dedicated To The Meeting "Genomic Impact Of Eukaryotic Transposable Elements" At Asilomar, Mark A. Batzer, Prescott L. Deininger, Jerzy Jurka, John V. Moran

Faculty Publications

The issues related to 'Genomic Impact of Eukaryotic Transposable Elements', which took place in Pacific Grove, California between March 31st and April 4th 2006, are discussed. The meeting celebrated the extraordinary contributions of Dr. Carl W. Schmid to the study of repeated DNA sequences and mobile elements. With the advent of recombinant DNA technology, he led the discovery of human Alu elements, and the discovery of their amplification. The idea of the conference was to gather and disseminate information in transposable elements (TEs) on the state-of-the-art tools and approaches. The core sessions from the conference covered research on transposable elements …


Identification And Characterization Of Novel Polymorphic Line-1 Insertions Through Comparison Of Two Human Genome Sequence Assemblies, Miriam K. Konkel, Jianxin Wang, Ping Liang, Mark A. Batzer Apr 2007

Identification And Characterization Of Novel Polymorphic Line-1 Insertions Through Comparison Of Two Human Genome Sequence Assemblies, Miriam K. Konkel, Jianxin Wang, Ping Liang, Mark A. Batzer

Faculty Publications

Mobile elements represent a relatively new class of markers for the study of human evolution. Long interspersed elements (LINEs) belong to a group of retrotransposons comprising approximately 21% of the human genome. Young LINE-1 (L1) elements that have integrated recently into the human genome can be polymorphic for insertion presence/absence in different human populations at particular chromosomal locations. To identify putative novel L1 insertion polymorphisms, we computationally compared two draft assemblies of the whole human genome (Public and Celera Human Genome assemblies). We identified a total of 148 potential polymorphic L1 insertion loci, among which 73 were candidates for novel …


Louisiana Agriculture Spring, 2007, Lsu Agcenter Apr 2007

Louisiana Agriculture Spring, 2007, Lsu Agcenter

Louisiana Agriculture

No abstract provided.


Formation Of Tellurium Nanocrystals During Anaerobic Growth Of Bacteria That Use Te Oxyanions As Respiratory Electron Acceptors, Shaun M. Baesman, Thomas D. Bullen, James Dewald, Donghui Zhang, Seamus Curran, Farhana S. Islam, Terry J. Beveridge, Ronald S. Oremland Apr 2007

Formation Of Tellurium Nanocrystals During Anaerobic Growth Of Bacteria That Use Te Oxyanions As Respiratory Electron Acceptors, Shaun M. Baesman, Thomas D. Bullen, James Dewald, Donghui Zhang, Seamus Curran, Farhana S. Islam, Terry J. Beveridge, Ronald S. Oremland

Faculty Publications

Certain toxic elements support the metabolism of diverse prokaryotes by serving as respiratory electron acceptors for growth. Here, we demonstrate that two anaerobes previously shown to be capable of respiring oxyanions of selenium also achieve growth by reduction of either tellurate [Te(VI)] or tellurite [Te(IV)] to elemental tellurium [Te(0)]. This reduction achieves a sizeable stable-Te-isotopic fractionation (isotopic enrichment factor [ε] = -0.4 to -1.0 per ml per atomic mass unit) and results in the formation of unique crystalline Te(0) nanoarchitectures as end products. The Te(0) crystals occur internally within but mainly externally from the cells, and each microorganism forms a …


Interspecific Spawning Between A Recent Immigrant And An Endemic Damselfish (Pisces: Pomacentridae) In The Hawaiian Islands, Karen P. Maruska, Kimberly A. Peyton Apr 2007

Interspecific Spawning Between A Recent Immigrant And An Endemic Damselfish (Pisces: Pomacentridae) In The Hawaiian Islands, Karen P. Maruska, Kimberly A. Peyton

Faculty Publications

The Indo-Pacific damselfish Abudefduf vaigiensis (Quoy & Gaimard, 1825) was first observed in the Hawaiian Islands in the early 1990s and is now clearly established as a breeding population in the Islands. Sightings of fish with color patterns intermediate between those of A. vaigiensis and the very similar endemic Hawaiian sergeant, Abudefduf abdominalis (Quoy & Gaimard, 1825), suggest that hybridization of the two has occurred naturally. This study provides direct evidence of crossbreeding from observations and video footage of two separate spawnings in nearshore waters of O'ahu and a third spawning in a public aquarium display tank. Reproductive behaviors were …


Induction Of Host Chemotactic Response By Encephalitozoon Spp., Jeffrey Fischer, Jeffrey West, Nnenaya Agochukwu, Colby Suire, Hollie Hale-Donze Apr 2007

Induction Of Host Chemotactic Response By Encephalitozoon Spp., Jeffrey Fischer, Jeffrey West, Nnenaya Agochukwu, Colby Suire, Hollie Hale-Donze

Faculty Publications

Microsporidians are a group of emerging pathogens typically associated with chronic diarrhea in immunocompromised individuals. The number of reports of infections with these organisms and the disseminated pathology is growing as diagnostic tools become more readily available. However, little is known about the innate immune response induced by and generated against these parasites. Using a coculture chemotaxis system, primary human macrophages were infected with Encephalitozoon cuniculi or Encephalitozoon intestinalis, and the recruitment of naïve monocytes was monitored. Encephalitozoon spp. induced an average threefold increase in migration of naïve cells 48 h postinfection, which corresponded to optimal infection of monocyte-derived- macrophages. …


Comparative Bacterial Diversity In Recent Hawaiian Volcanic Deposits Of Different Ages, Vicente Gomez-Alvarez, Gary M. King, Klaus Nüsslein Apr 2007

Comparative Bacterial Diversity In Recent Hawaiian Volcanic Deposits Of Different Ages, Vicente Gomez-Alvarez, Gary M. King, Klaus Nüsslein

Faculty Publications

Volcanic activity creates new landforms that can change dramatically over time as a consequence of biotic succession. Nonetheless, volcanic deposits present severe constraints for microbial colonization and activity. We have characterized bacterial diversity on four recent deposits at Kilauea volcano, Hawaii (KVD). Much of the diversity was either closely related to uncultured organisms or distinct from any reported 16S rRNA gene sequences. Diversity indices suggested that diversity was highest in a moderately vegetated 210-year-old ash deposit (1790-KVD), and lowest for a 79-year-old lava flow (1921-KVD). Diversity for a 41-year-old tephra deposit (1959-KVD) and a 300-year-old rainforest (1700-KVD) reached intermediate values. …


Corin I555(P568) Allele Is Associated With Enhanced Cardiac Hypertrophic Response To Increased Systemic Afterload, J. Eduardo Rame, Mark H. Drazner, Wendy Post, Ronald Peshock, Joao Lima, Richard S. Cooper, Daniel L. Dries Apr 2007

Corin I555(P568) Allele Is Associated With Enhanced Cardiac Hypertrophic Response To Increased Systemic Afterload, J. Eduardo Rame, Mark H. Drazner, Wendy Post, Ronald Peshock, Joao Lima, Richard S. Cooper, Daniel L. Dries

Faculty Publications

Corin activates pro-A-type naturetic peptide and pro-B-type naturetic peptide into biologically active molecules. We recently identified a minor allele in the corin gene defined by 2 highly linked single nucleotide polymorphisms (T555I and Q568P), which was associated with hypertension in blacks. Because of the direct antihypertrophic effects of the natriuretic peptide system, we hypothesized that the minor corin I555(P568) allele would be associated with an enhanced hypertrophic response to pressure overload. The relationship between systolic blood pressure and indexed left ventricular mass, derived from cardiac MRI, was analyzed in the Dallas Heart Study as a function of corin allele status. …


A Sine-Based Dichotomous Key For Primate Identification, Jacquelyn W. Zimmerman Apr 2007

A Sine-Based Dichotomous Key For Primate Identification, Jacquelyn W. Zimmerman

Honors Capstones

No abstract provided.


Paired Ig-Like Receptors Bind To Bacteria And Shape Tlr-Mediated Cytokine Production, Masafumi Nakayama, David M. Underhill, Timothy W. Petersen, Bin Li, Toshio Kitamura, Toshiyuki Takai, Alan Aderem Apr 2007

Paired Ig-Like Receptors Bind To Bacteria And Shape Tlr-Mediated Cytokine Production, Masafumi Nakayama, David M. Underhill, Timothy W. Petersen, Bin Li, Toshio Kitamura, Toshiyuki Takai, Alan Aderem

Faculty Publications

The innate immune system uses a wide variety of pattern recognition receptors including TLRs, scavenger receptors, and lectins to identify potential pathogens. A carefully regulated balance between activation and inhibition must be kept to avoid detrimental and inappropriate inflammatory responses. In this study, we identify murine-paired Ig-like receptor (PIR)-B, and its human orthologs Ig-like transcript 2 and Ig-like transcript 5 as novel receptors for Staphylococcus aureus. PIR-B contains four ITIM motifs and is thought to be an inhibitory receptor. Expression of these receptors enables NIH3T3 cells to bind S. aureus. In mouse bone marrow-derived macrophages, masking of PIR-B by anti-PIR …


A Sine-Based Dichotomous Key For Primate Identification, Scott W. Herke, Jinchuan Xing, David A. Ray, Jacquelyn W. Zimmerman, Richard Cordaux, Mark A. Batzer Apr 2007

A Sine-Based Dichotomous Key For Primate Identification, Scott W. Herke, Jinchuan Xing, David A. Ray, Jacquelyn W. Zimmerman, Richard Cordaux, Mark A. Batzer

Faculty Publications

For DNA samples or 'divorced' tissues, identifying the organism from which they were taken generally requires some type of analytical method. The ideal approach would be robust even in the hands of a novice, requiring minimal equipment, time, and effort. Genotyping SINEs (Short INterspersed Elements) is such an approach as it requires only PCR-related equipment, and the analysis consists solely of interpreting fragment sizes in agarose gels. Modern primate genomes are known to contain lineage-specific insertions of Alu elements (a primate-specific SINE); thus, to demonstrate the utility of this approach, we used members of the Alu family to identify DNA …


Different Evolutionary Fates Of Recently Integrated Human And Chimpanzee Line-1 Retrotransposons, Jungnam Lee, Richard Cordaux, Kyudong Han, Jianxin Wang, Dale J. Hedges, Ping Liang, Mark A. Batzer Apr 2007

Different Evolutionary Fates Of Recently Integrated Human And Chimpanzee Line-1 Retrotransposons, Jungnam Lee, Richard Cordaux, Kyudong Han, Jianxin Wang, Dale J. Hedges, Ping Liang, Mark A. Batzer

Faculty Publications

The long interspersed element-1 (LINE-1 or L1) is a highly successful retrotransposon in mammals. L1 elements have continued to actively propagate subsequent to the human-chimpanzee divergence, ∼ 6 million years ago, resulting in species-specific inserts. Here, we report a detailed characterization of chimpanzee-specific L1 subfamily diversity and a comparison with their human-specific counterparts. Our results indicate that L1 elements have experienced different evolutionary fates in humans and chimpanzees within the past ∼ 6 million years. Although the species-specific L1 copy numbers are on the same order in both species (1200-2000 copies), the number of retrotransposition-competent elements appears to be much …


Percolation In A Hierarchical Random Graph, D A Dawson, L G Gorostiza Apr 2007

Percolation In A Hierarchical Random Graph, D A Dawson, L G Gorostiza

Communications on Stochastic Analysis

No abstract provided.


The Purification Of Helicobacter Pylori Urease Β Subunit Protein And Dna For Vaccine Production, Alyson Moll Apr 2007

The Purification Of Helicobacter Pylori Urease Β Subunit Protein And Dna For Vaccine Production, Alyson Moll

Honors Capstones

No abstract provided.


Applying Model-View-Controller To An Embedded System Simulation, Joseph Dominic Cali Apr 2007

Applying Model-View-Controller To An Embedded System Simulation, Joseph Dominic Cali

Honors Capstones

No abstract provided.


Response Of A Native Bamboo [Arundinaria Gigantea (Walt.) Muhl.] In A Wind-Disturbed Forest, Paul R. Gagnon, William J. Platt, E. Barry Moser Mar 2007

Response Of A Native Bamboo [Arundinaria Gigantea (Walt.) Muhl.] In A Wind-Disturbed Forest, Paul R. Gagnon, William J. Platt, E. Barry Moser

Faculty Publications

Numerous bamboos are known to form extensive single-species stands, including species in the United States. Formerly prominent in the southeastern US, canebrakes are dense stands of the bamboos collectively called "cane" [Arundinaria (Michx)]. Canebrakes are now a critically endangered component of the bottomland hardwood forest ecosystem. Cane still occurs in its historic range, primarily in small remnant patches. A poor understanding of the ecological processes that generated large canebrakes limits their restoration and management. We hypothesize that cane's spreading clonal structure enables these bamboos to persist beneath a forest canopy and then respond rapidly to large-scale wind disturbances. We quantified …


Biogeochemical Stoichiometry Of Antarctic Dry Valley Ecosystems, J. E. Barrett, R. A. Virginia, W. B. Lyons, D. M. Mcknight, J. C. Priscu, P. T. Doran, A. G. Fountain, D. H. Wall, D. L. Moorhead Mar 2007

Biogeochemical Stoichiometry Of Antarctic Dry Valley Ecosystems, J. E. Barrett, R. A. Virginia, W. B. Lyons, D. M. Mcknight, J. C. Priscu, P. T. Doran, A. G. Fountain, D. H. Wall, D. L. Moorhead

Faculty Publications

Among aquatic and terrestrial landscapes of the McMurdo Dry Valleys, Antarctica, ecosystem stoichiometry ranges from values near the Redfield ratios for C:N:P to nutrient concentrations in proportions far above or below ratios necessary to support balanced microbial growth. This polar desert provides an opportunity to evaluate stoichiometric approaches to understand nutrient cycling in an ecosystem where biological diversity and activity are low, and controls over the movement and mass balances of nutrients operate over 10-106 years. The simple organisms (microbial and metazoan) comprising dry valley foodwebs adhere to strict biochemical requirements in the composition of their biomass, and when activated …


Geochemistry Of Martian Soil And Bedrock In Mantled And Less Mantled Terrains With Gamma Ray Data From Mars Odyssey, Horton E. Newsom, Larry S. Crumpler, Robert C. Reedy, Michael T. Petersen, Gary C. Newsom, Larry G. Evans, G. Jeffrey Taylor, John M. Keller, Daniel M. Janes, William V. Boynton, Kris E. Kerry, Suniti Karunatillake Mar 2007

Geochemistry Of Martian Soil And Bedrock In Mantled And Less Mantled Terrains With Gamma Ray Data From Mars Odyssey, Horton E. Newsom, Larry S. Crumpler, Robert C. Reedy, Michael T. Petersen, Gary C. Newsom, Larry G. Evans, G. Jeffrey Taylor, John M. Keller, Daniel M. Janes, William V. Boynton, Kris E. Kerry, Suniti Karunatillake

Faculty Publications

Surficial materials, including soil and dust, are abundant in the upper tens of centimeters of the Martian surface sensed by the Mars Odyssey Gamma Ray Spectrometer (GRS). Seven large areas (14% of the Martian surface) that represent possible compositional end-members were selected, including three regions heavily mantled with surficial materials. The selection process included mapping the ratio of exposed rocky terrain to surficial materials using high-resolution imagery. GRS data for H, Cl, Fe, Si, K, and Th were obtained for each area. The areas are chemically homogeneous within each area, given the spatial resolution and analytical uncertainty of the GRS …


Distinct Iron Binding Property Of Two Putative Iron Donors For The Iron-Sulfur Cluster Assembly: Isca And The Bacterial Frataxin Ortholog Cyay Under Physiological And Oxidative Stress Conditions, Huangen Ding, Juanjuan Yang, Liana C. Coleman, Simon Yeung Mar 2007

Distinct Iron Binding Property Of Two Putative Iron Donors For The Iron-Sulfur Cluster Assembly: Isca And The Bacterial Frataxin Ortholog Cyay Under Physiological And Oxidative Stress Conditions, Huangen Ding, Juanjuan Yang, Liana C. Coleman, Simon Yeung

Faculty Publications

Frataxin, a small mitochondrial protein linked to the neurodegenerative disease Friedreich ataxia, has recently been proposed as an iron donor for the iron-sulfur cluster assembly. An analogous function has also been attributed to IscA, a key member of the iron-sulfur cluster assembly machinery found in bacteria, yeast, and humans. Here we have compared the iron binding property of IscA and the frataxin ortholog CyaY from Escherichia coli under physiological and oxidative stress conditions. In the presence of the thioredoxin reductase system, which emulates the intracellular redox potential, CyaY fails to bind any iron even at a 10-fold excess of iron …