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Full-Text Articles in Life Sciences

Caenorhabditis Briggsae Methods, Scott Everet Baird, Helen M. Chamberlin Dec 2006

Caenorhabditis Briggsae Methods, Scott Everet Baird, Helen M. Chamberlin

Biological Sciences Faculty Publications

Caenorhabditis briggsae is being developed in parallel to C. elegans as a model system, primarily for the study of evolution. Like C. elegans, C. briggsae is a protandrous hermaphrodite and like C. elegans, its genome has been sequenced. From this point, these two model systems diverge. The development, behavior, and physiology of C. elegans have been characterized through tens of thousands of genetic and molecular studies. Genetic and molecular characterizations of C. briggsae are relatively few. Experimental resources in C. elegans include a high density recombination map that is well integrated with the genome sequence. The C. briggsae …


Evidence Of Influenza A Virus Rna In Siberian Lake Ice, Scott O. Rogers, Gang Zhang, Dany Shoham, David Gilchinsky, Sergei Davydov, John D. Castello Dec 2006

Evidence Of Influenza A Virus Rna In Siberian Lake Ice, Scott O. Rogers, Gang Zhang, Dany Shoham, David Gilchinsky, Sergei Davydov, John D. Castello

Biological Sciences Faculty Publications

Influenza A virus infects a large proportion of the human population annually, sometimes leading to the deaths of millions. The biotic cycles of infection are well characterized in the literature, including in studies of populations of humans, poultry, swine, and migratory waterfowl. However, there are few studies of abiotic reservoirs for this virus. Here, we report the preservation of influenza A virus genes in ice and water from high-latitude lakes that are visited by large numbers of migratory birds. The lakes are along the migratory flight paths of birds flying into Asia, North America, Europe, and Africa. The data suggest …


Desulfosporosinus Lacus Sp. Nov., A Sulfate-Reducing Bacterium Isolated From Pristine Freshwater Lake Sediments, S. Ramamoorthy, H. Sass, H. Langner, P. Schumann, R. M. Kroppenstedt, S. Spring, J. Overmann, R. Frank Rosenzweig Dec 2006

Desulfosporosinus Lacus Sp. Nov., A Sulfate-Reducing Bacterium Isolated From Pristine Freshwater Lake Sediments, S. Ramamoorthy, H. Sass, H. Langner, P. Schumann, R. M. Kroppenstedt, S. Spring, J. Overmann, R. Frank Rosenzweig

Biological Sciences Faculty Publications

A novel sulfate-reducing bacterium was isolated from pristine sediments of Lake Stechlin, Germany. This strain, STP12 , was found to contain predominantly c-type cytochromes and to reduce sulfate, sulfite and thiosulfate using lactate as an electron donor. Although STP12 could not utilize elemental sulfur as an electron acceptor, it could support growth by dissimilatory Fe(III) reduction. In a comparison of 16S rRNA gene sequences, STP12 was 96.7 % similar to Desulfosporosinus auripigmenti DSM 13351 , 96.5 % similar to Desulfosporosinus meridiei DSM 13257 and 96.4 % similar to Desulfosporosinus orientis DSM 765 . DNA-DNA hybridization experiments revealed that strain STP12 …


A Sex-Linked Allele, Autosomal Modifiers And Temperature-Dependence Appear To Regulate Melanism In Male Mosquitofish (Gambusia Holbrooki), Lisa Horth Dec 2006

A Sex-Linked Allele, Autosomal Modifiers And Temperature-Dependence Appear To Regulate Melanism In Male Mosquitofish (Gambusia Holbrooki), Lisa Horth

Biological Sciences Faculty Publications

About 1% of male mosquitofish (Gambusia holbrooki) express melanic (mottled-black) body coloration, which differs dramatically from the wild-type, silvery-gray coloration. Here, I report on the genetic inheritance pattern of melanic coloration, which indicates Y-linkage, and at least one autosomal modifier. Phenotypic expression of melanism is also affected by temperature. Expression is constitutive ( temperature insensitive) in some populations, inducible ( temperature sensitive) in others. Constitutive and inducible expression occur among geographically proximal populations. However, males from any single population demonstrate the same constitutive or inducible expression pattern as one another. The F1 males from inter-population crosses demonstrate temperature-related …


Oligomerization Of Hepatitis C Virus Core Protein Is Crucial For Interaction With The Cytoplasmic Domain Of E1 Envelope Protein, Kousuke Nakai, Toru Okamoto, Tomomi Kimura-Someya, Koji Ishii, Chang Kweng Lim, Hideki Tani, Eiko Matsuo, Takayuki Abe, Yoshio Mori, Tetsuro Suzuki, Tatsuo Miyamura, Jack H. Nunberg, Kohji Moriishi, Yoshiharu Matsuura Nov 2006

Oligomerization Of Hepatitis C Virus Core Protein Is Crucial For Interaction With The Cytoplasmic Domain Of E1 Envelope Protein, Kousuke Nakai, Toru Okamoto, Tomomi Kimura-Someya, Koji Ishii, Chang Kweng Lim, Hideki Tani, Eiko Matsuo, Takayuki Abe, Yoshio Mori, Tetsuro Suzuki, Tatsuo Miyamura, Jack H. Nunberg, Kohji Moriishi, Yoshiharu Matsuura

Biological Sciences Faculty Publications

Hepatitis C virus (HCV) contains two membrane-associated envelope glycoproteins, E1 and E2, which assemble as a heterodimer in the endoplasmic reticulum (ER). In this study, predictive algorithms and genetic analyses of deletion mutants and glycosylation site variants of the E1 glycoprotein were used to suggest that the glycoprotein can adopt two topologies in the ER membrane: the conventional type I membrane topology and a polytopic topology in which the protein spans the ER membrane twice with an intervening cytoplasmic loop (amino acid residues 288 to 360). We also demonstrate that the E1 glycoprotein is able to associate with the HCV …


The Effects Of Postfire Salvage Logging On Cavity-Nesting Birds, Richard L. Hutto, Susan M. Gallo Nov 2006

The Effects Of Postfire Salvage Logging On Cavity-Nesting Birds, Richard L. Hutto, Susan M. Gallo

Biological Sciences Faculty Publications

We investigated the effects of postfire salvage logging on cavity-nesting birds by comparing nest densities and patterns of nest reuse over a three-year period in seven logged and eight unlogged patches of mixed-conifer forest in the Blackfoot-Clearwater Wildlife Management Area, Montana. We found 563 active nests of 18 cavity-nesting birds; all species were found nesting in the uncut burned forest plots, but only eight nested in the salvage-logged plots. All except one species nested at a higher density in the unlogged areas, and half of the species were significantly more abundant in the unlogged plots. Every timber-drilling and timber-gleaning species …


Essential Elements Of A Defense-Review Of Dna Testing Results, Dan E. Krane Oct 2006

Essential Elements Of A Defense-Review Of Dna Testing Results, Dan E. Krane

Biological Sciences Faculty Publications

No abstract provided.


Effects Of Long-Term Hypoxia On Enzymes Of Carbohydrate Metabolism In The Gulf Killifish, Fundulus Grandis, Bernard Rees Oct 2006

Effects Of Long-Term Hypoxia On Enzymes Of Carbohydrate Metabolism In The Gulf Killifish, Fundulus Grandis, Bernard Rees

Biological Sciences Faculty Publications

The goal of the current study was to generate a comprehensive, multi-tissue perspective of the effects of chronic hypoxic exposure on carbohydrate metabolism in the Gulf killifish Fundulus grandis. Fish were held at approximately 1.3 mg l(-1) dissolved oxygen (approximately 3.6 kPa) for 4 weeks, after which maximal activities were measured for all glycolytic enzymes in four tissues (white skeletal muscle, liver, heart and brain), as well as for enzymes of glycogen metabolism (in muscle and liver) and gluconeogenesis (in liver). The specific activities of enzymes of glycolysis and glycogen metabolism were strongly suppressed by hypoxia in white skeletal muscle, …


Frequent Fire Alters Nitrogen Transformations In Ponderosa Pine Stands Of The Inland Northwest, Thomas H. Gremer, Anna Sala Oct 2006

Frequent Fire Alters Nitrogen Transformations In Ponderosa Pine Stands Of The Inland Northwest, Thomas H. Gremer, Anna Sala

Biological Sciences Faculty Publications

Recurrent, low-severity fire in ponderosa pine (Pinus ponderosa)linterior Douglas-fir (Pseudotsuga menziesii var. glauca) forests is thought to have directly influenced nitrogen (N) cycling and availability. However, no studies to date have investigated the influence of natural fire intervals on soil processes in undisturbed forests, thereby limiting our ability to understand ecological processes and successional dynamics in this important ecosystem of the Rocky Mountain West. Here, we tested the standing hypothesis that recurrent fire in ponderosa pine/Douglas-fir forests of the Inland Northwest decreases total soil N, but increases N turnover and nutrient availability. We compared soils in stands unburned over the …


Consumers Limit The Abundance And Dynamics Of A Perennial Shrub With A Seed Bank, Matthew J. Kauffman, John L. Maron Oct 2006

Consumers Limit The Abundance And Dynamics Of A Perennial Shrub With A Seed Bank, Matthew J. Kauffman, John L. Maron

Biological Sciences Faculty Publications

For nearly 30 years, ecologists have argued that predators of seeds and seedlings seldom have population-level effects on plants with persistent seed banks and density-dependent seedling survival. We parameterized stage-based population models that incorporated density dependence and seed dormancy with data from a 5.5-year experiment that quantified how granivorous mice and herbivorous voles influence bush lupine (Lupinus arboreus) demography. We asked how seed dormancy and density-dependent seedling survival mediate the impacts of these consumers in dune and grassland habitats. In dune habitat, mice reduced analytical lambda (the intrinsic rate of population growth) by 39%, the equilibrium number of above-ground plants …


Invasion Through Quantitative Effects: Intense Shade Drives Native Decline And Invasive Success, Kurt O. Reinhart, Julie Gurnee, Reyes Tirado, Ragan M. Callaway Oct 2006

Invasion Through Quantitative Effects: Intense Shade Drives Native Decline And Invasive Success, Kurt O. Reinhart, Julie Gurnee, Reyes Tirado, Ragan M. Callaway

Biological Sciences Faculty Publications

The effects of invasive nonnative species on community composition are well documented. However, few studies have determined the mechanisms by which invaders drive these changes. The literature indicates that many nonnative plant species alter light availability differently than natives in a given community, suggesting that shading may be such a mechanism. We compared light quantity (photosynthetically active radiation, PAR) and quality (red : far-red ratio, R:Fr) in riparian reaches heavily invaded by a nonnative tree (Acer platanoides) to that in an uninvaded forest and experimentally tested the effects of our measured differences in PAR and R:Fr on the …


Detection Of Panulirus Argus Virus 1 (Pav1) In The Caribbean Spiny Lobster Using Fluorescence In Situ Hybridization (Fish), Caiwen Li, Jeffrey D. Shields, Hamish J. Small, Kimberly S. Reece, Carmony L. Hartwig, Roland A. Cooper, Robert E. Ratzlaff Oct 2006

Detection Of Panulirus Argus Virus 1 (Pav1) In The Caribbean Spiny Lobster Using Fluorescence In Situ Hybridization (Fish), Caiwen Li, Jeffrey D. Shields, Hamish J. Small, Kimberly S. Reece, Carmony L. Hartwig, Roland A. Cooper, Robert E. Ratzlaff

Biological Sciences Faculty Publications

Panulirus argus Virus 1 (PaV1) is the first virus known to be pathogenic to a wild lobster. It infects the Caribbean spiny lobster P. argus from the Florida Keys, and has a predilection for juveniles. The monitoring of the virus in wild populations and study of its behavior in the laboratory require the development of reliable diagnostic tools. A sensitive and specific fluorescence in situ hybridization (FISH) assay was developed for detection of PaV1. The lower detection limit using a 110 bp DNA probe in a dot-blot hybridization for PaV1 DNA was 10 pg of cloned template PaV1 DNA and …


Broad Specificity Of Mammalian Adenylyl Cyclase For Interaction With 2',3'-Substituted Purine- And Pyrimidine Nucleotide Inhibitors, Tung-Chung Mou, Andreas Gille, Srividya Suryanarayana, Mark Richter, Roland Seifert, Stephen R. Sprang Sep 2006

Broad Specificity Of Mammalian Adenylyl Cyclase For Interaction With 2',3'-Substituted Purine- And Pyrimidine Nucleotide Inhibitors, Tung-Chung Mou, Andreas Gille, Srividya Suryanarayana, Mark Richter, Roland Seifert, Stephen R. Sprang

Biological Sciences Faculty Publications

Membrane adenylyl cyclases (mACs) play an important role in signal transduction and are therefore potential drug targets. Earlier, we identified 2',3'-O-(N-methylanthraniloyl) (MANT)-substituted purine nucleotides as a novel class of highly potent competitive mAC inhibitors (Ki values in the 10 nM range). MANT nucleotides discriminate among various mAC isoforms through differential interactions with a binding pocket localized at the interface between the C1 and C2 domains of mAC. In this study, we examine the structure/activity relationships for 2',3'-substituted nucleotides and compare the crystal structures of mAC catalytic domains (VC1:IIC2) bound to MANT-GTP, MANT-ATP, and 2',3'-(2,4,6-trinitrophenyl) (TNP)-ATP. TNP-substituted purine and pyrimidine nucleotides …


Role Of The Stable Signal Peptide Of Junín Arenavirus Envelope Glycoprotein In Ph-Dependent Membrane Fusion, Joanne York, Jack H. Nunberg Aug 2006

Role Of The Stable Signal Peptide Of Junín Arenavirus Envelope Glycoprotein In Ph-Dependent Membrane Fusion, Joanne York, Jack H. Nunberg

Biological Sciences Faculty Publications

The envelope glycoprotein of the arenaviruses (GP-C) is unusual in that the mature complex retains the cleaved, 58-amino-acid signal peptide. Association of this stable signal peptide (SSP) has been shown to be essential for intracellular trafficking and proteolytic maturation of the GP-C complex. We identify here a specific and previously unrecognized role of SSP in pH-dependent membrane fusion. Amino acid substitutions that alter the positive charge at lysine K33 in SSP affect the ability of GP-C to mediate cell-cell fusion and the threshold pH at which membrane fusion is triggered. Based on the presumed location of K33 at or near …


Molecular Population Genetics And Phenotypic Diversification Of Two Populations Of The Thermophilic Cyanobacterium Mastigocladus Laminosus, Scott R. Miller, Michael D. Purugganan, Stephanie E. Curtis Aug 2006

Molecular Population Genetics And Phenotypic Diversification Of Two Populations Of The Thermophilic Cyanobacterium Mastigocladus Laminosus, Scott R. Miller, Michael D. Purugganan, Stephanie E. Curtis

Biological Sciences Faculty Publications

We investigated the distributions of genetic and phenotypic variation for two Yellowstone National Park populations of the heterocyst-forming cyanobacterium Mastigocladus (Fischerella) laminosus that exhibit dramatic phenotypic differences as a result of environmental differences in nitrogen availability. One population develops heterocysts and fixes nitrogen in situ in response to a deficiency of combined nitrogen in its environment, whereas the other population does neither due to the availability of a preferred nitrogen source. Slowly evolving molecular markers, including the 16S rRNA gene and the downstream internal transcribed spacer, are identical among all laboratory isolates from both populations but belie considerable genetic and …


Disturbance Facilitates Invasion: The Effects Are Stronger Abroad Than At Home, José L. Hierro, Diego Villarreal, Özkan Eren, Jon M. Graham, Ragan M. Callaway Aug 2006

Disturbance Facilitates Invasion: The Effects Are Stronger Abroad Than At Home, José L. Hierro, Diego Villarreal, Özkan Eren, Jon M. Graham, Ragan M. Callaway

Biological Sciences Faculty Publications

Disturbance is one of the most important factors promoting exotic invasion. However, if disturbance per se is sufficient to explain exotic success, then "invasion" abroad should not differ from "colonization" at home. Comparisons of the effects of disturbance on organisms in their native and introduced ranges are crucial to elucidate whether this is the case; however, such comparisons have not been conducted. We investigated the effects of disturbance on the success of Eurasian native Centaurea solstitialis in two invaded regions, California and Argentina, and one native region, Turkey, by conducting field experiments consisting of simulating different disturbances and adding locally …


Mbet3p Is Required For Homotypic Copii Vesicle Tethering In Mammalian Cells, Sidney Yu, Ayano Satoh, Marc Pypaert, Karl Mullen, Jesse C. Hay, Susan Ferro-Novick Jul 2006

Mbet3p Is Required For Homotypic Copii Vesicle Tethering In Mammalian Cells, Sidney Yu, Ayano Satoh, Marc Pypaert, Karl Mullen, Jesse C. Hay, Susan Ferro-Novick

Biological Sciences Faculty Publications

TRAPPI is a large complex that mediates the tethering of COPII vesicles to the Golgi (heterotypic tethering) in the yeast Saccharomyces cerevisiae. In mammalian cells, COPII vesicles derived from the transitional endoplasmic reticulum (tER) do not tether directly to the Golgi, instead, they appear to tether to each other ( homotypic tethering) to form vesicular tubular clusters (VTCs). We show that mammalian Bet3p (mBet3p), which is the most highly conserved TRAPP subunit, resides on the tER and adjacent VTCs. The inactivation of mBet3p results in the accumulation of cargo in membranes that colocalize with the COPII coat. Furthermore, using an …


Linking Scales In Stream Ecology, Winsor H. Lowe, Gene E. Likens, Mary E. Power Jul 2006

Linking Scales In Stream Ecology, Winsor H. Lowe, Gene E. Likens, Mary E. Power

Biological Sciences Faculty Publications

The hierarchical structure of natural systems can be useful in designing ecological studies that are informative at multiple spatial scales. Although stream systems have long been recognized as having a hierarchical spatial structure, there is a need for more empirical research that exploits this structure to generate an understanding of population biology, community ecology, and species-ecosystem linkages across spatial scales. We review studies that link pattern and process across multiple scales of stream-habitat organization, highlighting the insight derived from this multiscale approach and the role that mechanistic hypotheses play in its successful application. We also describe afrontier in stream research …


Estimating Detection Probablities Of River Birds Using Double Surveys, Robert J. Fletcher Jr., Richard L. Hutto Jul 2006

Estimating Detection Probablities Of River Birds Using Double Surveys, Robert J. Fletcher Jr., Richard L. Hutto

Biological Sciences Faculty Publications

We describe a method for surveying birds in river habitats that allows for rapid assessment across broad spatial scales and estimation of detection probabilities. Our river survey approach incorporates a double-survey technique, whereby observers in two canoes simultaneously survey birds along a river reach. Data are in the form of a two-sample mark-recapture history, and covariates suspected of influencing detection probabilities can be included in the modeling process and evaluated using information-theoretic approaches. We provide an example using the method along the Madison and upper Missouri rivers in Montana. Overall, detection probabilities for each observer ranged from 57% to 89%, …


Stress Responses In Tropical Sparrows: Comparing Tropical And Temperate Zonotrichia, Haruka Wada, Ignacio T. Moore, Creagh W. Breuner, John C. Wingfield Jul 2006

Stress Responses In Tropical Sparrows: Comparing Tropical And Temperate Zonotrichia, Haruka Wada, Ignacio T. Moore, Creagh W. Breuner, John C. Wingfield

Biological Sciences Faculty Publications

Seasonal modulation of the adrenocortical response appears to be ubiquitous in mid- to high- latitude vertebrates but has not been investigated in tropical vertebrates. Previous studies demonstrate that temperate passerines show seasonality in corticosterone secretion and corticosteroid binding globulin capacities. We examined seasonal and sex differences in the stress response in an equatorial population of Zonotrichia capensis, the only Zonotrichia that breeds in the tropics, and compared the results with those of northern Zonotrichia. Seasonal differences in tropical Zonotrichia would presumably be independent of photoperiod and thus directly related to such activities as reproduction and feather molt. In addition, we …


Facilitation By Pinus Flexilis During Succession: A Hierarchy Of Mechanisms Benefits Other Plant Species, Dayna Baumeister, Ragan M. Callaway Jul 2006

Facilitation By Pinus Flexilis During Succession: A Hierarchy Of Mechanisms Benefits Other Plant Species, Dayna Baumeister, Ragan M. Callaway

Biological Sciences Faculty Publications

Studies of facilitation have primarily been limited to single mechanisms, species, or environments. We examined interacting mechanisms governing the facilitative effects of Pinus flexilis on two later successional understory species, Pseudotsuga menziesii and Ribes cereum, in different microhabitats and seasons at the ecotone between the Rocky Mountain forests and Great Plains grasslands in Montana, USA. In field surveys, 69% of Pseudotsuga and 91% of Ribes were located beneath P. flexilis even though P. flexilis subcrowns accounted for a small proportion of available habitat. For three years, we monitored the survival of Pseudotsuga and Ribes seedlings experimentally planted beneath …


Role Of The Stable Signal Peptide And Cytoplasmic Domain Of G2 In Regulating Intracellular Transport Of The Junín Virus Envelope Glycoprotein Complex, Sudhakar S. Agnihothram, Joanne York, Jack H. Nunberg Jun 2006

Role Of The Stable Signal Peptide And Cytoplasmic Domain Of G2 In Regulating Intracellular Transport Of The Junín Virus Envelope Glycoprotein Complex, Sudhakar S. Agnihothram, Joanne York, Jack H. Nunberg

Biological Sciences Faculty Publications

Enveloped viruses utilize the membranous compartments of the host cell for the assembly and budding of new virion particles. In this report, we have investigated the biogenesis and trafficking of the envelope glycoprotein (GP-Q of the Junin arenavirus. The mature GP-C complex is unusual in that it retains a stable signal peptide (SSP) as an essential component in association with the typical receptor-binding (G1) and transmembrane fusion (G2) subunits. We demonstrate that, in the absence of SSP, the G1-G2 precursor is restricted to the endoplasmic reticulum (ER). This constraint is relieved by coexpression of SSP in trans, allowing transit of …


Environmental Signals Generate A Differential And Coordinated Expression Of The Heme Receptor Gene Family Of Bartonella Quintana, James M. Battisti, Kate N. Sappington, Laura S, Smitherman, Nermi L. Parrow, Michael F. Minnick Jun 2006

Environmental Signals Generate A Differential And Coordinated Expression Of The Heme Receptor Gene Family Of Bartonella Quintana, James M. Battisti, Kate N. Sappington, Laura S, Smitherman, Nermi L. Parrow, Michael F. Minnick

Biological Sciences Faculty Publications

Of all bacteria, Bartonella quintana has the highest reported in vitro hemin requirement, yet an explanation for this remains elusive. To produce diseases such as trench fever, endocarditis, and bacillary angiomatosis, B. quintana must survive and replicate in the disparate environments of the Pediculus humanus corporis (body louse) gut and the human vasculature. We previously identified a five-member family of hemin binding proteins (Hbps) synthesized by B. quintana that bind hemin on the outer surface but share no similarity to known bacterial heme receptors. In the present study, we examine the transcription, regulation, and synthesis of this virulence factor family …


Invasive Plant Suppresses The Growth Of Native Tree Seedlings By Disrupting Belowground Mutualisms, Kristina A. Stinson, Stuart A. Campbell, Jeff R. Powell, Benjamin E. Wolfe, Ragan M. Callaway, Giles C. Thelen, Steven G. Hallett, Daniel Prati, John N. Klironomos May 2006

Invasive Plant Suppresses The Growth Of Native Tree Seedlings By Disrupting Belowground Mutualisms, Kristina A. Stinson, Stuart A. Campbell, Jeff R. Powell, Benjamin E. Wolfe, Ragan M. Callaway, Giles C. Thelen, Steven G. Hallett, Daniel Prati, John N. Klironomos

Biological Sciences Faculty Publications

The impact of exotic species on native organisms is widely acknowledged, but poorly understood. Very few studies have empirically investigated how invading plants may alter delicate ecological interactions among resident species in the invaded range. We present novel evidence that antifungal phytochemistry of the invasive plant, Alliaria petiolata, a European invader of North American forests, suppresses native plant growth by disrupting mutualistic associations between native canopy tree seedlings and belowground arbuscular mycorrhizal fungi. Our results elucidate an indirect mechanism by which invasive plants can impact native flora, and may help explain how this plant successfully invades relatively undisturbed forest habitat.


A Framework For Understanding Ecological Traps And An Evaluation Of Existing Evidence, Bruce A. Robertson, Richard L. Hutto May 2006

A Framework For Understanding Ecological Traps And An Evaluation Of Existing Evidence, Bruce A. Robertson, Richard L. Hutto

Biological Sciences Faculty Publications

When an animal settles preferentially in a habitat within which it does poorly relative to other available habitats, it is said to have been caught in an “ecological trap.” Although the theoretical possibility that animals may be so trapped is widely recognized, the absence of a clear mechanistic understanding of what constitutes a trap means that much of the literature cited as support for the idea may be weak, at best. Here, we develop a conceptual model to explain how an ecological trap might work, outline the specific criteria that are necessary for demonstrating the existence of an ecological trap, …


What Use Is Half A Wing In The Ecology And Evolution Of Birds?, Kenneth P. Dial, Ross J. Randall, Terry R. Dial May 2006

What Use Is Half A Wing In The Ecology And Evolution Of Birds?, Kenneth P. Dial, Ross J. Randall, Terry R. Dial

Biological Sciences Faculty Publications

The use of incipient wings during ontogeny in living birds reveals not only the function of these developing forelimbs in growing birds’ survival but also the possible employment of protowings during transitional stages in the evolution of flight. When startled, juvenile galliform birds attempt aerial flight even though their wings are not fully developed. They also flap their incipient wings when they run up precipitous inclines, a behavior we have described as wing-assisted incline running (WAIR), and when they launch from elevated structures. The functional benefit of beating these protowings has only recently been evaluated. We report the first ontogenetic …


Unexpected Diversity And Complexity Of The Guerrero Negro Hypersaline Microbial Mat, Ruth E. Ley, J. Kirk Harris, Joshua Wilcox, John R. Spear, Scott R. Miller, Brad M. Bebout, Julia A. Maresca, Donald A. Bryant, Mithcell L. Sogin, Norman R. Pace May 2006

Unexpected Diversity And Complexity Of The Guerrero Negro Hypersaline Microbial Mat, Ruth E. Ley, J. Kirk Harris, Joshua Wilcox, John R. Spear, Scott R. Miller, Brad M. Bebout, Julia A. Maresca, Donald A. Bryant, Mithcell L. Sogin, Norman R. Pace

Biological Sciences Faculty Publications

We applied nucleic acid-based molecular methods, combined with estimates of biomass (ATP), pigments, and microelectrode measurements of chemical gradients, to map microbial diversity vertically on a millimeter scale in a hypersaline microbial mat from Guerrero Negro, Baja California Sur, Mexico. To identify the constituents of the mat, small-subunit rRNA genes were amplified by PCR from community genomic DNA extracted from layers, cloned, and sequenced. Bacteria dominated the mat and displayed unexpected and unprecedented diversity. The majority (1,336) of the 1,586 bacterial 16S rRNA sequences generated were unique, representing 752 species (>= 97% rRNA sequence identity) in 42 of the …


Time For International Policies On Biological Invasions, Inderjit, Ragan M. Callaway, Shalini Kaushik Mar 2006

Time For International Policies On Biological Invasions, Inderjit, Ragan M. Callaway, Shalini Kaushik

Biological Sciences Faculty Publications

No abstract provided.


Photo Processes On Self-Associated Cationic Porphyrins And Plastocyanin Complexes 1. Ligation Of Plastocyanin Tyrosine 83 Onto Metalloporphyrins And Electron-Transfer Fluorescence Quenching, Hewa Anula, Eugene Myshkin, Anton Guliaev, Charles Luman, Evgeny Danilov, Felix Castellano, George S. Bullerjahn, Michael Rogers Feb 2006

Photo Processes On Self-Associated Cationic Porphyrins And Plastocyanin Complexes 1. Ligation Of Plastocyanin Tyrosine 83 Onto Metalloporphyrins And Electron-Transfer Fluorescence Quenching, Hewa Anula, Eugene Myshkin, Anton Guliaev, Charles Luman, Evgeny Danilov, Felix Castellano, George S. Bullerjahn, Michael Rogers

Biological Sciences Faculty Publications

The spectroscopic properties of the self-associated complexes formed between the anionic surface docking site of spinach plastocyanin and the cationic metalloporphyrins, in which the tyrosine 83 (Y83) moiety is placed just below the docking site, tetrakis(N-methyl-4-pyridyl)porphyrin (Pd(II)TMPyP4+ and Zn(II)TMPyP4+), have been studied and reported herein. The fluorescence quenching phenomenon of the self-assembled complex of Zn(II)TMPyP4+/plastocyanin has also been discovered. The observed red-shifting of the Soret and Q-bands of the UV-visible spectra, ca. 9 nm for Pd(II)TMPyP4+/plastocyanin and ca. 6 nm for the Zn(II)TMPyP4+/ plastocyanin complexes, was explained in terms of exciton theory coupled with the Gouterman model. Thus, the hydroxyphenyl …


Mutations Conferring Aminoglycoside And Spectinomycin Resistance In Borrelia Burgdorferi, Daniel Criswell, Virginia L. Tobiason, J. Stephen Lodmell, D. Scott Samuels Feb 2006

Mutations Conferring Aminoglycoside And Spectinomycin Resistance In Borrelia Burgdorferi, Daniel Criswell, Virginia L. Tobiason, J. Stephen Lodmell, D. Scott Samuels

Biological Sciences Faculty Publications

We have isolated and characterized in vitro mutants of the Lyme disease agent Borrelia burgdorferi that are resistant to spectinomycin, kanamycin, gentamicin, or streptomycin, antibiotics that target the small subunit of the ribosome. 16S rRNA mutations A1185G and C1186U, homologous to Escherichia coli nucleotides A1191 and C1192, conferred > 2,200-fold and 1,300-fold resistance to spectinomycin, respectively. A 16S rRNA A1402G mutation, homologous to E. coli A1408, conferred > 90-fold resistance to kanamycin and > 240-fold resistance to gentamicin. Two mutations were identified in the gene for ribosomal protein S12, at a site homologous to E. coli residue Lys-87, in mutants selected in streptomycin. …