Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Medicine and Health Sciences (162)
- Systems Biology (158)
- Medical Sciences (123)
- Ecology and Evolutionary Biology (99)
- Physical Sciences and Mathematics (81)
-
- Animal Sciences (80)
- Immunology and Infectious Disease (56)
- Entomology (49)
- Oceanography and Atmospheric Sciences and Meteorology (46)
- Biodiversity (42)
- Marine Biology (40)
- Parasitology (40)
- Genetics and Genomics (32)
- Environmental Sciences (30)
- Zoology (29)
- Plant Sciences (28)
- Aquaculture and Fisheries (23)
- Climate (22)
- Diseases (20)
- Natural Resources and Conservation (17)
- Botany (16)
- Genetics (15)
- Microbiology (15)
- Education (14)
- Physiology (13)
- Biochemistry, Biophysics, and Structural Biology (11)
- Forest Sciences (10)
- Oceanography (10)
- Institution
- Keyword
-
- Climate change (22)
- Ticks (20)
- Animals (14)
- Virginia (12)
- Biodiversity (11)
-
- Evolution (11)
- Ixodes scapularis (11)
- Algae (10)
- Conservation (9)
- Borrelia burgdorferi (8)
- Cyanobacteria (8)
- Dermacentor variabilis (8)
- Herbivory (8)
- Phytoplankton (8)
- Small mammals (8)
- Acorn woodpecker (7)
- Bacteria (7)
- Coral bleaching (7)
- Coral reefs (7)
- Corals (7)
- Gene expression (7)
- Biological Sciences (6)
- Biomass (6)
- Competition (6)
- Cooperative breeding (6)
- Dispersal (6)
- Ecology (6)
- Fitness (6)
- Index Medicus (6)
- Lyme disease (6)
- Publication Year
- File Type
Articles 721 - 750 of 1156
Full-Text Articles in Biology
Extant Or Extinct? White-Tailed Jack Rabbits And Yellowstone's Food Web, Joel Berger
Extant Or Extinct? White-Tailed Jack Rabbits And Yellowstone's Food Web, Joel Berger
Biological Sciences Faculty Publications
No abstract provided.
Novel Weapons: Invasive Plant Suppresses Fungal Mutualists In America But Not In Its Native Europe, Ragan M. Callaway, Don Cipollini, Kathryn Barto, Giles C. Thelen, Steven G. Hallett, Daniel Prati, Kristina Stinson, John Klironomos
Novel Weapons: Invasive Plant Suppresses Fungal Mutualists In America But Not In Its Native Europe, Ragan M. Callaway, Don Cipollini, Kathryn Barto, Giles C. Thelen, Steven G. Hallett, Daniel Prati, Kristina Stinson, John Klironomos
Biological Sciences Faculty Publications
Why some invasive plant species transmogrify from weak competitors at home to strong competitors abroad remains one of the most elusive questions in ecology. Some evidence suggests that disproportionately high densities of some invaders are due to the release of biochemicals that are novel, and therefore harmful, to naïve organisms in their new range. So far, such evidence has been restricted to the direct phytotoxic effects of plants on other plants. Here we found that one of North America's most aggressive invaders of undisturbed forest understories, Alliaria petiolata (garlic mustard) and a plant that inhibits mycorrhizal fungal mutualists of North …
Indirect Effects And Traditional Trophic Cascades: A Test Involving Wolves, Coyotes, And Pronghorn, Kim Murray Berger, Eric M. Gese, Joel Berger
Indirect Effects And Traditional Trophic Cascades: A Test Involving Wolves, Coyotes, And Pronghorn, Kim Murray Berger, Eric M. Gese, Joel Berger
Biological Sciences Faculty Publications
The traditional trophic cascades model is based on consumer - resource interactions at each link in a food chain. However, trophic-level interactions, such as mesocarnivore release resulting from intraguild predation, may also be important mediators of cascades. From September 2001 to August 2004, we used spatial and seasonal heterogeneity in wolf distribution and abundance in the southern Greater Yellowstone Ecosystem to evaluate whether mesopredator release of coyotes ( Canis latrans), resulting from the extirpation of wolves ( Canis lupus), accounts for high rates of coyote predation on pronghorn ( Antilocapra americana) fawns observed in some areas. Results of this ecological …
Dynamics In The Transient Complex Of Plastocyanin-Cytochrome F From Prochlorothrix Hollandica, Rinske Hulsker, Maria Baranova, George S. Bullerjahn, Marcellus Ubbink
Dynamics In The Transient Complex Of Plastocyanin-Cytochrome F From Prochlorothrix Hollandica, Rinske Hulsker, Maria Baranova, George S. Bullerjahn, Marcellus Ubbink
Biological Sciences Faculty Publications
The nature of transient protein complexes can range from a highly dynamic ensemble of orientations to a single well-defined state. This represents variation in the equilibrium between the encounter and final, functional state. The transient complex between plastocyanin (Pc) and cytochrome f (cyt of the cyanobacterium Prochlorothrix hollandica was characterized by NMR spectroscopy. Intermolecular pseudocontact shifts and chemical shift perturbations were used as restraints in docking calculations to determine the structure of the wild-type Pc-cytf complex. The orientation of Pc is similar to orientations found in Pc-cytf complexes from other sources. Electrostatics seems to play a modest role in complex …
Tachinid Collecting In Southwest New Mexico And Arizona During The 2007 Nads Field Meeting, John O. Stireman Iii
Tachinid Collecting In Southwest New Mexico And Arizona During The 2007 Nads Field Meeting, John O. Stireman Iii
Biological Sciences Faculty Publications
The 2007 field meeting of the North American Dipterists Society (NADS) was held August 13–16 in southwestern New Mexico, centered in Silver City (at Western New Mexico University), and the surrounding Gila National Forest. This was the first NADS meeting that I have been able to attend, and I think I can speak for all in saying it was enjoyable, productive, and interesting; an overall success. A more detailed account and evaluation of this meeting is available in the 2007 Fly Times article (O’Hara 2007).
A Method To Determine 18 O Kinetic Isotope Effects In The Hydrolysis Of Nucleotide Triphosphates, Xinlin Du, Kurt Ferguson, Robert Gregory, Stephen R. Sprang
A Method To Determine 18 O Kinetic Isotope Effects In The Hydrolysis Of Nucleotide Triphosphates, Xinlin Du, Kurt Ferguson, Robert Gregory, Stephen R. Sprang
Biological Sciences Faculty Publications
A method to determine 18 O kinetic isotope effects (KIEs) in the hydrolysis of GTP that is generally applicable to reactions involving other nucleotide triphosphates is described. Internal competition, where the substrate of the reaction is a mixture of 18 O-labeled and unlabeled nucleotides, is employed, and the change in relative abundance of the two species in the course of the reaction is used to calculate KIE. The nucleotide labeled with 18 O at sites of mechanistic interest also contains 13C at all carbon positions, whereas the 16 O-labeled nucleotide is depleted of 13C. The relative abundance of the labeled …
Genomic Organization And Phylogenetic Utility Of Deer Mouse (Peromyscus Maniculatus) Lymphotoxin-Alpha And Lymphotoxin-Beta, Tiffany Richens, Aparna D.N. Palmer, Joseph Prescott, Tony Schountz
Genomic Organization And Phylogenetic Utility Of Deer Mouse (Peromyscus Maniculatus) Lymphotoxin-Alpha And Lymphotoxin-Beta, Tiffany Richens, Aparna D.N. Palmer, Joseph Prescott, Tony Schountz
Biological Sciences Faculty Publications
BACKGROUND: Deer mice (Peromyscus maniculatus) are among the most common mammals in North America and are important reservoirs of several human pathogens, including Sin Nombre hantavirus (SNV). SNV can establish a life-long apathogenic infection in deer mice, which can shed virus in excrement for transmission to humans. Patients that die from hantavirus cardiopulmonary syndrome (HCPS) have been found to express several proinflammatory cytokines, including lymphotoxin (LT), in the lungs. It is thought that these cytokines contribute to the pathogenesis of HCPS. LT is not expressed by virus-specific CD4+ T cells from infected deer mice, suggesting a limited role for this …
Competitive Abilities Of Native Grasses And Non-Native (Bothriochloa Spp.) Grasses, Cheryl D. Schmidt, Rob Channell Ph.D., Karen R. Hickman, Keith Harmoney, William J. Stark Ph.D.
Competitive Abilities Of Native Grasses And Non-Native (Bothriochloa Spp.) Grasses, Cheryl D. Schmidt, Rob Channell Ph.D., Karen R. Hickman, Keith Harmoney, William J. Stark Ph.D.
Biological Sciences Faculty Publications
Old World Bluestems (OWB), introduced from Europe and Asia in the 1920s, recently have begun to raise concerns in the Great Plains. Despite suggestion in the late 1950s that OWB were weedy and negatively impacted biological diversity, they were widely introduced throughout the Great Plains for agricultural purposes. Anecdotal evidence suggests that OWB exhibit invasive characteristics that promote competitive exclusion of native species. The objective of our study was to quantify the competitive abilities of two OWB species (Caucasian bluestem; Bothriochloa bladhii (Retz.) S. T. Blake (= Bothriochloa caucasica (Trin.) C. E. Hubb.) and yellow bluestem; Bothriochloa ischaemum (L.) Keng) …
What Constitutes A Natural Fire Regime? Insight From The Ecology And Distribution Of Coniferous Forest Birds In North America, Richard L. Hutto, Courtney J. Conway, Victoria A. Saab, Jeffrey R. Walters
What Constitutes A Natural Fire Regime? Insight From The Ecology And Distribution Of Coniferous Forest Birds In North America, Richard L. Hutto, Courtney J. Conway, Victoria A. Saab, Jeffrey R. Walters
Biological Sciences Faculty Publications
Bird species that specialize in the use of burned forest conditions can provide insight into the prehistoric fire regimes associated with the forest types that they have occupied over evolutionary time. The nature of their adaptations reflects the specific post-fire conditions that occurred prior to the unnatural influence of humans after European settlement. Specifically, the post-fire conditions, nest site locations, and social systems of two species (Bachman's sparrow [Aimophila aestivalis] and red-cockaded woodpecker [Picoides borealis]) suggest that, prehistorically, a frequent, low-severity fire regime characterized the southeastern pine system in which they evolved. In contrast, the patterns …
Population Ecology Of The Golden Mouse, Robert K. Rose
Population Ecology Of The Golden Mouse, Robert K. Rose
Biological Sciences Faculty Publications
An understanding of the population dynamics of a species requires knowledge of the major life-history parameters of a population, including age at maturity, distribution of age classes, and lifetime reproductive contribution of the sexes, sex ratio, length of the breeding season, mean litter size, rates of growth and survival, and life span. Because few long-term studies have been conducted with Ochrotomys nuttalli as the focal species of investigation, only fragmentary information is available for many population parameters. As importantly, densities of golden mice often are low, making them difficult to evaluate statistically. Little has been published on age at maturity …
Scientific Review For The Identification Of Critical Habitat For Woodland Caribou (Rangifer Tarandus Caribou), Boreal Population, In Canada, Mark Hebblewhite, Environment Canada
Scientific Review For The Identification Of Critical Habitat For Woodland Caribou (Rangifer Tarandus Caribou), Boreal Population, In Canada, Mark Hebblewhite, Environment Canada
Biological Sciences Faculty Publications
Woodland Caribou (Rangifer tarandus caribou), Boreal Population (herein referred to as boreal caribou), are formally listed as Threatened under the federal Species at Risk Act (SARA). The Act requires the Minister of Environment to prepare a Recovery Strategy for the species that includes, to the extent possible and based upon the best available information, an identifi cation of its Critical Habitat and/or, if there is insuffi cient information available, a Schedule of Studies to determine that information. In August 2007, Environment Canada (EC) launched a science-based review with the mandate to identify Critical Habitat to the extent possible, using the …
Greenfall Links Groundwater To Aboveground Food Webs In Desert River Floodplains, John L. Sabo, Kevin E. Mccluney, Yevgeniy Marusenko, Andrew Keller, Candan U. Soykan
Greenfall Links Groundwater To Aboveground Food Webs In Desert River Floodplains, John L. Sabo, Kevin E. Mccluney, Yevgeniy Marusenko, Andrew Keller, Candan U. Soykan
Biological Sciences Faculty Publications
Groundwater makes up nearly 99% of unfrozen freshwater worldwide and sustains riparian trees rooted in shallow aquifers, especially in arid and semiarid climates. The goal of this paper is to root animals in the regional water cycle by quantifying the significance of groundwater to riparian animals. We focused our efforts on the cricket, Gryllus alogus: a common primary consumer found in floodplain forests along the San Pedro River, in southeast Arizona, USA. Cottonwood trees make groundwater available to G. alogus as dislodged, groundwater-laden leaves (greenfall). We hypothesized that groundwater fluxes mediated by greenfall sustain G. allogus through the prolonged dry …
Oviposition Behavior Partitions Aquatic Landscapes Along Predation And Nutrient Gradients, C. A. Binckley, W. J. Resetarits Jr.
Oviposition Behavior Partitions Aquatic Landscapes Along Predation And Nutrient Gradients, C. A. Binckley, W. J. Resetarits Jr.
Biological Sciences Faculty Publications
That individuals attempt to minimize the ratio of mortality risk/growth rate (μ/g) when foraging within individual habitat patches is well established. Do species partition among spatially discrete communities embedded in complex landscapes in a similar manner? We investigated how 3 ovipositing species (2 Hyla treefrogs and a hydrophilid beetle, Tropisternus lateralis) responded to simultaneous gradients of nutrients and predation risk. Species partitioned our experimental metacommunity primarily by reducing oviposition with fish. Tropisternus positively responded to increased nutrients, but the effect decreased with increasing risk, as predicted by μ/g theory. Use of fish habitats by Tropisternus was unrelated to breeding …
Accelerated Exchange Of Exon Segments In Viperid Three-Finger Toxin Genes (Sistrurus Catenatus Edwardsii; Desert Massasauga), Robin Doley, Susanta Pahari, Stephen P. Mackessy, Manjunatha Kini
Accelerated Exchange Of Exon Segments In Viperid Three-Finger Toxin Genes (Sistrurus Catenatus Edwardsii; Desert Massasauga), Robin Doley, Susanta Pahari, Stephen P. Mackessy, Manjunatha Kini
Biological Sciences Faculty Publications
BACKGROUND: Snake venoms consist primarily of proteins and peptides showing a myriad of potent biological activities which have been shaped by both adaptive and neutral selective forces. Venom proteins are encoded by multigene families that have evolved through a process of gene duplication followed by accelerated evolution in the protein coding region. RESULTS: Here we report five gene structures of three-finger toxins from a viperid snake, Sistrurus catenatus edwardsii. These toxin genes are structured similarly to elapid and hydrophiid three-finger toxin genes, with two introns and three exons. Both introns and exons show distinct patterns of segmentation, and the insertion/deletion …
Genome-Wide Compensatory Changes Accompany Drug-Selected Mutations In The Plasmodium Falciparum Crt Gene, Hongying Jiang, Jigar J. Patel, Ming Yi, Jianbing Mu, Jinhui Ding, Robert Stephens, Roland A. Cooper, Michael T. Ferdig, Xin-Zhuan Su
Genome-Wide Compensatory Changes Accompany Drug-Selected Mutations In The Plasmodium Falciparum Crt Gene, Hongying Jiang, Jigar J. Patel, Ming Yi, Jianbing Mu, Jinhui Ding, Robert Stephens, Roland A. Cooper, Michael T. Ferdig, Xin-Zhuan Su
Biological Sciences Faculty Publications
Mutations in PfCRT (Plasmodium falciparum chloroquine-resistant transporter), particularly the substitution at amino acid position 76, confer chloroquine (CQ) resistance in P. falciparum. Point mutations in the homolog of the mammalian multidrug resistance gene (pfmdr1) can also modulate the levels of CQ response. Moreover, parasites with the same pfcrt and pfmdr1 alleles exhibit a wide range of drug sensitivity, suggesting that additional genes contribute to levels of CQ resistance (CQR). Reemergence of CQ sensitive parasites after cessation of CQ use indicates that changes in PfCRT are deleterious to the parasite. Some CQR parasites, however, persist in the …
Swimming Dynamics And Propulsive Efficiency Of Squids Throughout Ontogeny, Ian K. Bartol, Paul S. Krueger, Joseph T. Thompson, William J. Stewart
Swimming Dynamics And Propulsive Efficiency Of Squids Throughout Ontogeny, Ian K. Bartol, Paul S. Krueger, Joseph T. Thompson, William J. Stewart
Biological Sciences Faculty Publications
Synopsis Squids encounter vastly different flow regimes throughout ontogeny as they undergo critical morphological changes to their two locomotive systems: the fins and jet. Squid hatchlings (paralarvae) operate at low and intermediate Reynolds numbers (Re) and typically have rounded bodies, small fins, and relatively large funnel apertures whereas juveniles and adults operate at higher Re and generally have more streamlined bodies, larger fins, and relatively small funnel apertures. These morphological changes and varying flow conditions affect swimming performance in squids. To determine how swimming dynamics and propulsive efficiency change throughout ontogeny, digital particle image velocimetry (DPIV) and kinematic …
Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes
Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes
Biological Sciences Faculty Publications
Compared to insects, little is known about innate immunity in ticks. This chapter addresses the molecular processes that recognize non-self and the cellular and molecular processes mobilized to phagocytose, engulf, inhibit or kill invaders. We discuss the receptors that recognize pathogen associated molecular patterns (PAMPs) and the putative up-regulation of regulatory cascades that lead, ultimately, to cellular or molecular responses. We describe the molecular events that activate the cellular processes and the array of humoral factors that are mobilized against invading organisms, including antimicrobial peptides, proteases and protease inhibitors, lectins, coagulation factors and others. Special attention is directed to the …
Historical Mammal Extinction On Christmas Island (Indian Ocean) Correlates With Introduced Infectious Disease, Kelly B. Wyatt, Paula F. Campos, M. Thomas P. Gilbert, Sergios-Orestis Kolokotronis, Wayne H. Hynes, Rob Desalle, Peter Daszak, Ross D.E. Macphee, Alex D. Greenwood
Historical Mammal Extinction On Christmas Island (Indian Ocean) Correlates With Introduced Infectious Disease, Kelly B. Wyatt, Paula F. Campos, M. Thomas P. Gilbert, Sergios-Orestis Kolokotronis, Wayne H. Hynes, Rob Desalle, Peter Daszak, Ross D.E. Macphee, Alex D. Greenwood
Biological Sciences Faculty Publications
It is now widely accepted that novel infectious disease can be a leading cause of serious population decline and even outright extinction in some invertebrate and vertebrate groups (e. g., amphibians). In the case of mammals, however, there are still no well-corroborated instances of such diseases having caused or significantly contributed to the complete collapse of species. A case in point is the extinction of the endemic Christmas Island rat (Rattus macleari): although it has been argued that its disappearance ca. AD 1900 may have been partly or wholly caused by a pathogenic trypanosome carried by fleas hosted …
A Novel Zinc-Binding Domain Is Essential For Formation Of The Functional Junin Virus Envelope Glycoprotein Complex, Joanne York, Jack H. Nunberg
A Novel Zinc-Binding Domain Is Essential For Formation Of The Functional Junin Virus Envelope Glycoprotein Complex, Joanne York, Jack H. Nunberg
Biological Sciences Faculty Publications
The envelope glycoprotein of the Junin arenavirus (GP-C) mediates entry into target cells through a pH-dependent membrane fusion mechanism. Unlike other class I viral fusion proteins, the mature GP-C complex retains a cleaved, 58-amino-acid signal peptide (SSP) as an essential subunit, required both for trafficking of GP-C to the cell surface and for the activation of membrane fusion. SSP has been shown to associate noncovalently in GP-C via the cytoplasmic domain (CTD) of the transmembrane fusion subunit G2. In this report we investigate the molecular basis for this intersubunit interaction. We identify an invariant series of six cysteine and histidine …
Pattern Analysis Of Microtubule-Polymerizing And -Depolymerizing Agent Combinations As Cancer Chemotherapies, Carol A. Heckman, S. O. Uppal, Y. Li, E. Wendt, M. L. Cayer, J. Barnes, D. Conway, N. Boudreau
Pattern Analysis Of Microtubule-Polymerizing And -Depolymerizing Agent Combinations As Cancer Chemotherapies, Carol A. Heckman, S. O. Uppal, Y. Li, E. Wendt, M. L. Cayer, J. Barnes, D. Conway, N. Boudreau
Biological Sciences Faculty Publications
Subcellular distribution of mass can be analyzed by a technique that involves culturing cells on interferometers and digitizing their interference contours. Contour sampling resulted in 102 variables per cell, which were predictors of oncogenic transformation. Cell phenotypes can be deconstructed by use of latent factors, which represent the covariance of the real variables. The reversal of the cancertype phenotype by a combination of microtubule- stabilizing and -depolymerizing agents was described previously. The implications of these results have been explored by clinicians who treated patients with the combination of docetaxel and vinorelbine (Navelbine®). The current study was performed to determine the …
Vertebrate Osmoregulation: A Student Laboratory Exercise Using Teleost Fish, Bernard Rees
Vertebrate Osmoregulation: A Student Laboratory Exercise Using Teleost Fish, Bernard Rees
Biological Sciences Faculty Publications
Anaerobic metabolism is recruited in vertebrates under conditions of intense exercise or lowered environmental oxygen availability (hypoxia), typically resulting in the accumulation of lactate in blood and tissues. Lactate will be cleared over time after the reoxygenation of tissues, eventually returning to control levels. Here, we present a laboratory exercise developed as part of an upper-level vertebrate physiology class that demonstrates the effects of exercise and hypoxia exposure on blood lactate in fish and the subsequent decrease in lactate during recovery. Typically, the results obtained by students demonstrate that both treatments cause significant increases in blood lactate concentrations (two to …
Fundulus As The Premier Teleost Model In Environmental Biology: Opportunities For New Insights Using Genomics, Bernard Rees
Fundulus As The Premier Teleost Model In Environmental Biology: Opportunities For New Insights Using Genomics, Bernard Rees
Biological Sciences Faculty Publications
A strong foundation of basic and applied research documents that the estuarine fish Fundulus heteroclitus and related species are unique laboratory and field models for understanding how individuals and populations interact with their environment. In this paper we summarize an extensive body of work examining the adaptive responses of Fundulus species to environmental conditions, and describe how this research has contributed importantly to our understanding of physiology, gene regulation, toxicology, and ecological and evolutionary genetics of teleosts and other vertebrates. These explorations have reached a critical juncture at which advancement is hindered by the lack of genomic resources for these …
Structural Biology: A Receptor Unlocked, Stephen R. Sprang
Structural Biology: A Receptor Unlocked, Stephen R. Sprang
Biological Sciences Faculty Publications
No abstract provided.
Additive And Synergistic Bactericidal Activity Of Antibodies Directed Against Minor Outer Membrane Proteins Of Neisseria Meningitidis, Vincent E. Weynants, Christiane M. Feron, Karine K. Goraj, Martine P. Bos, Philippe A. Denoeal, Vincent G. Verlant, Jan Tommassen, Ian R. A. Peak, Ralph C. Judd, Michael P. Jennings, Jan T. Poolman
Additive And Synergistic Bactericidal Activity Of Antibodies Directed Against Minor Outer Membrane Proteins Of Neisseria Meningitidis, Vincent E. Weynants, Christiane M. Feron, Karine K. Goraj, Martine P. Bos, Philippe A. Denoeal, Vincent G. Verlant, Jan Tommassen, Ian R. A. Peak, Ralph C. Judd, Michael P. Jennings, Jan T. Poolman
Biological Sciences Faculty Publications
Neisseria meningitidis serogroup B is a major cause of bacterial meningitis in younger populations. The available vaccines are based on outer membrane vesicles obtained from wild-type strains. In children less than 2 years old they confer protection only against strains expressing homologous PorA, a major, variable outer membrane protein (OMP). We genetically modified a strain in order to eliminate PorA and to overproduce one or several minor and conserved OMPs. Using a mouse model mimicking children's PorA-specific bactericidal activity, it was demonstrated that overproduction of more than one minor OMP is required to elicit antibodies able to induce complement-mediated killing …
Evaluating Forensic Dna Evidence - A Day-Long Workshop, Dan E. Krane, William C. Thompson
Evaluating Forensic Dna Evidence - A Day-Long Workshop, Dan E. Krane, William C. Thompson
Biological Sciences Faculty Publications
No abstract provided.
Native Plant Diversity Resists Invasion At Both Low And High Resource Levels, John L. Maron, Marilyn Marler
Native Plant Diversity Resists Invasion At Both Low And High Resource Levels, John L. Maron, Marilyn Marler
Biological Sciences Faculty Publications
Human modification of the environment is causing both loss of species and changes in resource availability. While studies have examined how species loss at the local level can influence invasion resistance, interactions between species loss and other components of environmental change remain poorly studied. In particular, the manner in which native diversity interacts with resource availability to influence invasion resistance is not well understood. We created experimental plant assemblages that varied in native species (1–16 species) and/or functional richness (defined by rooting morphology and phenology; one to five functional groups). We crossed these diversity treatments with resource (water) addition to …
The Unusual 23s Rrna Gene Of Coxiella Burnetii: Two Self-Splicing Group I Introns Flank A 34-Base-Pair Exon, And One Element Lacks The Canonical Omega G, Rahul Raghavan, Scott R. Miller, Linda D. Hicks, Michael F. Minnick
The Unusual 23s Rrna Gene Of Coxiella Burnetii: Two Self-Splicing Group I Introns Flank A 34-Base-Pair Exon, And One Element Lacks The Canonical Omega G, Rahul Raghavan, Scott R. Miller, Linda D. Hicks, Michael F. Minnick
Biological Sciences Faculty Publications
We describe the presence and characteristics of two self-splicing group I introns in the sole 23S rRNA gene of Coxiella burnetii. The two group I introns, Cbu.L1917 and Cbu.L1951, are inserted at sites 1917 and 1951 (Escherichia coli numbering), respectively, in the 23S rRNA gene of C. bumetii. Both introns were found to be self-splicing in vivo and in vitro even though the terminal nucleotide of Cbu.L1917 is adenine and not the canonical conserved guanine, termed Omega G, found in Cbu.L1951 and all other group I introns described to date. Predicted secondary structures for both introns were constructed and revealed …
Transcriptional Regulation Of The Heme Binding Protein Gene Family Of Bartonella Quintana Is Accomplished By A Novel Promoter Element And Iron Response Regulator, James M. Battisti, Laura S. Smitherman, Kate N. Sappington, Nermi L. Parrow, Rahul Raghavan, Michael F. Minnick
Transcriptional Regulation Of The Heme Binding Protein Gene Family Of Bartonella Quintana Is Accomplished By A Novel Promoter Element And Iron Response Regulator, James M. Battisti, Laura S. Smitherman, Kate N. Sappington, Nermi L. Parrow, Rahul Raghavan, Michael F. Minnick
Biological Sciences Faculty Publications
We previously identified a five-member family of hemin-binding proteins (Hbp's) of Bartonella quintana that bind hemin on the outer surface but share no homology with known bacterial heme receptors. Subsequently, we demonstrated that expression of the hbp family is significantly influenced by oxygen, heme, and temperature conditions encountered by the pathogen in the human host and the body louse vector; e.g., we observed a dramatic (>100-fold) increase in hbpC transcript levels in response to the "louse-like" temperature of 30 degrees C. The goal of the present study was to identify a transcription factor(s) involved in the coordinated and differential …
Hiv-2 Rna Dimerization Is Regulated By Intramolecular Interactions In Vitro, Tayyba T. Baig, Jean-Marc Lanchy, J. Stephen Lodmell
Hiv-2 Rna Dimerization Is Regulated By Intramolecular Interactions In Vitro, Tayyba T. Baig, Jean-Marc Lanchy, J. Stephen Lodmell
Biological Sciences Faculty Publications
Genomic RNA dimerization is an essential process in the retroviral replication cycle. In vitro, HIV-2 RNA dimerization is mediated at least in part by direct intermolecular interaction at stem-loop 1 (SL1) within the 5'-untranslated leader region (UTR). RNA dimerization is thought to be regulated via alternate presentation and sequestration of dimerization signals by intramolecular base- pairings. One of the proposed regulatory elements is a palindrome sequence ( pal) located upstream of SL1. To investigate the role of pal in the regulation of HIV-2 dimerization, we randomized this motif and selected in vitro for dimerization- competent and dimerization-impaired RNAs. Energy minimization …
High Rates Of Sulfate Reduction In A Low-Sulfate Hot Spring Microbial Mat Are Driven By A Low Level Of Diversity Of Sulfate-Respiring Microorganisms, Jesse G. Dillon, Susan Fishbain, Scott R. Miller, Brad M. Bebout, Kristen S. Habicht, Samuel M. Webb, David A. Stahl
High Rates Of Sulfate Reduction In A Low-Sulfate Hot Spring Microbial Mat Are Driven By A Low Level Of Diversity Of Sulfate-Respiring Microorganisms, Jesse G. Dillon, Susan Fishbain, Scott R. Miller, Brad M. Bebout, Kristen S. Habicht, Samuel M. Webb, David A. Stahl
Biological Sciences Faculty Publications
The importance of sulfate respiration in the microbial mat found in the low-sulfate thermal outflow of Mushroom Spring in Yellowstone National Park was evaluated using a combination of molecular, microelectrode, and radiotracer studies. Despite very low sulfate concentrations, this mat community was shown to sustain a highly active sulfur cycle. The highest rates of sulfate respiration were measured close to the surface of the mat late in the day when photosynthetic oxygen production ceased and were associated with a Thermodesuffiovibrio-like population. Reduced activity at greater depths was correlated with novel populations of sulfate-reducing microorganisms, unrelated to characterized species, and most …