Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 17 of 17
Full-Text Articles in Biology
Long-Toed Salamanders In Harvested And Intact Douglas-Fir Forests Of Western Montana, George P. Naughton, Colin B. Henderson, Kerry R. Foresman, Rex L. Mcgraw Ii
Long-Toed Salamanders In Harvested And Intact Douglas-Fir Forests Of Western Montana, George P. Naughton, Colin B. Henderson, Kerry R. Foresman, Rex L. Mcgraw Ii
Biological Sciences Faculty Publications
There is little known about how timber harvest practices have affected terrestrial amphibians in the northern Rocky Mountains. Especially lacking is information on the effects of revised harvest methods that fall within the framework of environmental or New Forestry. We estimated the relative abundance of a common forest amphibian, the long-toed salamander (Ambystoma macrodactylum) captured in pitfall arrays on intact, environmentally harvested, and overstory-removal harvested sites in mixed-conifer forests of western Montana. Pitfall data from 1994 through 1996 showed that previously logged sites contained significantly fewer long-toed salamanders regardless of harvest method used. The number of salamanders captured …
Characterization Of Borrelia Burgdorferi Blya And Blyb Proteins: A Prophage-Encoded Holin-Like System, Christopher J. Damman, Christian H. Eggers, D. Scott Samuels
Characterization Of Borrelia Burgdorferi Blya And Blyb Proteins: A Prophage-Encoded Holin-Like System, Christopher J. Damman, Christian H. Eggers, D. Scott Samuels
Biological Sciences Faculty Publications
The conserved cp32 plasmid family of Borrelia burgdorferi was recently shown to be packaged into a bacteriophage particle (C. H. Eggers and D. S. Samuels, J. Bacteriol. 181:7308-7313, 1999), This plasmid encodes BlyA, a 7.4-kDa membrane-interactive protein, and BlyB, an accessory protein, which were previously proposed to comprise a hemolysis system. Our genetic and biochemical evidence suggests that this hypothesis is incorrect and that BlyA and BlyB function instead as a prophage-encoded holin or holin-like system for this newly described bacteriophage, An Escherichia coli mutant containing the blyAB locus that was defective for the normally cryptic host hemolysin SheA was …
Sensitivity Of Species Habitat-Relationship Model Performance To Factors Of Scale, J. W. Karl, P. J. Heglund, E. O. Garton, J. M. Scott, N. M. Wright, Richard L. Hutto
Sensitivity Of Species Habitat-Relationship Model Performance To Factors Of Scale, J. W. Karl, P. J. Heglund, E. O. Garton, J. M. Scott, N. M. Wright, Richard L. Hutto
Biological Sciences Faculty Publications
Researchers have come to different conclusions about the usefulness of habitat-relationship models for predicting species presence or absence. This difference frequently stems from a failure to recognize the effects of spatial scales at which the models are applied. We examined the effects of model complexity, spatial data resolution, and scale of application on the performance of bird habitat relationship (BHR) models on the Craig Mountain Wildlife Management Area and on the Idaho portion of the U.S. Forest Service's Northern Region. We constructed and tested BHR models for 60 bird species detected on the study areas. The models varied by three …
Hemin-Binding Surface Protein From Bartonella Quintana, James A. Carroll, Sherry A. Coleman, Laura S. Smitherman, Michael F. Minnick
Hemin-Binding Surface Protein From Bartonella Quintana, James A. Carroll, Sherry A. Coleman, Laura S. Smitherman, Michael F. Minnick
Biological Sciences Faculty Publications
Bartonella quintana, the agent of trench fever and a cause of endocarditis and bacillary angiomatosis in humans, has the highest reported in vitro hemin requirement for any bacterium. We determined that eight membrane-associated proteins from B. quintana bind hemin and that a similar to 25-kDa protein (HbpA) was the dominant hemin binding protein. Like many outer membrane proteins, HbpA partitions to the detergent phase of a Triton X-114 extract of the cell and is heat modifiable, displaying an apparent molecular mass shift from approximately 25 to 30 kDa when solubilized at 100 degreesC. Immunoblots of purified outer and inner membranes …
Monitoring Bacterial Transport By Stable Isotope Enrichment Of Cells, William Holben, Peggy H. Ostrom
Monitoring Bacterial Transport By Stable Isotope Enrichment Of Cells, William Holben, Peggy H. Ostrom
Biological Sciences Faculty Publications
Understanding the transport and behavior of bacteria in the environment has broad implications in diverse areas, ranging from agriculture to groundwater quality, risk assessment, and bioremediation. The ability to reliably track and enumerate specific bacterial populations in the context of native communities and environments is key to developing this understanding. We report a novel bacterial tracking approach, based on altering the stable carbon isotope value (delta C-13) Of bacterial cells, which provides specific and sensitive detection and quantification of those cells in environmental samples. This approach was applied to the study of bacterial transport in saturated porous media. The transport …
Facilitation May Buffer Competitive Effects: Indirect And Diffuse Interactions Among Salt Marsh Plants, Ragan M. Callaway, Steven C. Pennings
Facilitation May Buffer Competitive Effects: Indirect And Diffuse Interactions Among Salt Marsh Plants, Ragan M. Callaway, Steven C. Pennings
Biological Sciences Faculty Publications
Direct interactions among plant species may be highly modified by indirect or diffuse effects within a multispecies community. We investigated the direct and diffuse effects of two salt marsh perennials, Monanthechloe littoralis and Arthrocnemum subterminale, on winter annuals and the perennial herb Limonium californicum in a salt marsh in central California. In permanent plots, Monanthechloe had expanded substantially in the upper marsh over the past 13 yr, while Arthrocnemum and all annual species had decreased. These dynamics suggest that Monanthechloe may directly outcompete most other species in the upper marsh. In contrast, Arthrocnemum is known to facilitate some annual species. …
A Biochemical Mechanism For Nonrandom Mutations And Evolution, Barbara E. Wright
A Biochemical Mechanism For Nonrandom Mutations And Evolution, Barbara E. Wright
Biological Sciences Faculty Publications
No abstract provided.
Outcrossing Rate And Inbreeding Depression In The Perennial Yellow Bush Lupine, Lupinus Arboreus (Fabaceae), Pamela Kittelson, John L. Maron
Outcrossing Rate And Inbreeding Depression In The Perennial Yellow Bush Lupine, Lupinus Arboreus (Fabaceae), Pamela Kittelson, John L. Maron
Biological Sciences Faculty Publications
Little is known about the breeding systems of perennial Lupinus species. We provide information about the breeding system of the perennial yellow bush lupine, Lupinus arboreus, specifically determining self-compatibility, outcrossing rate, and level of inbreeding depression. Flowers are self-compatible, but autonomous self-fertilization rarely occurs; thus selfed seed are a product of facilitated selfing. Based on four isozyme loci from 34 maternal progeny arrays of seeds we estimated an outcrossing rate of 0.78. However, when we accounted for differential maturation of selfed seeds, the outcrossing rate at fertilization was lower, ∼0.64. Fitness and inbreeding depression of 11 selfed and outcrossed families …
The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors
The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors
Biological Sciences Faculty Publications
Coastal marine ecosystems worldwide are being altered rapidly by the invasion of nonindigenous species. Unlike terrestrial and freshwater systems, the impacts of an invading species have never been quantified on multiple trophic levels for a marine food web. We measured the impact of the nonindigenous green crab, Carcinus maenas, on a coastal marine food web in central California and found that this predator exerted strong “top-down” control, significantly reducing the abundances of several of the 20 invertebrate species monitored over a 9-yr period. Densities of native clams, Nutricola tantilla and Nutricola confusa, and native shore crabs, Hemigrapsus oregonensis, showed 5-fold …
Integrating Development With Evolution: A Case Study With Beetle Horns, Douglas J. Emlen
Integrating Development With Evolution: A Case Study With Beetle Horns, Douglas J. Emlen
Biological Sciences Faculty Publications
No abstract provided.
Disruption Of The Borrelia Burgdorferi Gac Gene, Encoding The Naturally Synthesized Gyra C-Terminal Domain, Scott W. Knight, Betsy J. Kimmel, Christian H. Eggers, D. Scott Samuels
Disruption Of The Borrelia Burgdorferi Gac Gene, Encoding The Naturally Synthesized Gyra C-Terminal Domain, Scott W. Knight, Betsy J. Kimmel, Christian H. Eggers, D. Scott Samuels
Biological Sciences Faculty Publications
The C-terminal domain of the A subunit of DNA gyrase, which we term Gac, is naturally synthesized in Borrelia burgdorferi as an abundant DNA-binding protein. Full-length GyrA, which includes the C-terminal domain, is also synthesized by the spirochete and functions as a subunit of DNA gyrase, We have disrupted synthesis of Gac as an independent protein and demonstrated that it is not essential for growth in a coumarin-resistant background. We detected no alterations in DNA maintenance, condensation, or topology In B. burgdorferi lacking this small DNA-binding protein.
The Advantages Of Clonal Integration Under Different Ecological Conditions: A Community-Wide Test, Steven C. Pennings, Ragan M. Callaway
The Advantages Of Clonal Integration Under Different Ecological Conditions: A Community-Wide Test, Steven C. Pennings, Ragan M. Callaway
Biological Sciences Faculty Publications
The "connectedness" of clonal plants has been shown to promote survival and growth in a variety of single-species, single-factor studies, but experiments comparing the relative advantages of clonality across multiple habitats and species are rare, raising the concern that generalizations about the benefits of clonality might be biased by the particular species or habitat studied. We studied the importance of clonal integration in southeastern USA salt marsh plants, using all six of the common clonal species in the community, by following the success of intact and severed clonal fragments invading three habitat treatments. Clonal integration was most important for growth …
A Bacteriophage-Like Particle From Bartonella Bacilliformis, Kent D. Barbian, Michael F. Minnick
A Bacteriophage-Like Particle From Bartonella Bacilliformis, Kent D. Barbian, Michael F. Minnick
Biological Sciences Faculty Publications
Bartonella bacilliformis and Bartonella henselae, the respective agents of Oroya fever and cat-scratch disease in humans, are known to produce bacteriophage-like particles (BLPs) that package 14 kbp segments of the host chromosome. Data from this study suggest that other Bartonella species including Bartonella quintana, Bartonella doshiae and Bartonella grahamii also contain similar BLPs, as evidenced by the presence of a 14 kbp extrachromosomal DNA element in their genomes, whereas Bartonella elizabethae and Bartonella clarridgeiae do not. A purification scheme utilizing chloroform, DNase I and centrifugation was devised to isolate BLPs from B. bacilliformis. Intact BLPs were observed by transmission electron …
Stress And Developmental Stability: Vegetation Removal Causes Increased Fluctuating Asymmetry In Shrews, Alexander V. Badyaev, Kerry R. Foresman, Miguel V. Fernandes
Stress And Developmental Stability: Vegetation Removal Causes Increased Fluctuating Asymmetry In Shrews, Alexander V. Badyaev, Kerry R. Foresman, Miguel V. Fernandes
Biological Sciences Faculty Publications
Environmental stress can increase phenotypic variation in populations by affecting developmental stability of individuals. While such increase in variation results from individual differences in ability to buffer stress, groups of individuals and different traits may have different sensitivity to stressful conditions. For example, the sex that is under stronger directional selection for faster growth may be more sensitive to stressful conditions during development. On an individual level, stress-induced variation in a trait may be related to the strength of stabilizing selection that acts on the trait. We experimentally examined sensitivity of mandibular development to stress in a free-living population of …
Genetic Variation Among Endosymbionts Of Widely Distributed Vestimentiferan Tubeworms, Carol A. Di Meo, Ami E. Wilbur, William E. Holben, Robert A. Feldman, Robert C. Vrijenhoek, S. Craig Cary
Genetic Variation Among Endosymbionts Of Widely Distributed Vestimentiferan Tubeworms, Carol A. Di Meo, Ami E. Wilbur, William E. Holben, Robert A. Feldman, Robert C. Vrijenhoek, S. Craig Cary
Biological Sciences Faculty Publications
Vestimentiferan tubeworms thriving in sulfidic deep-sea hydrothermal vents and cold seeps are constrained by their nutritional reliance on chemoautotrophic endosymbionts. In a recent phylogenetic study using 16S ribosomal DNA, we found that endosymbionts from vent and seep habitats form two distinct clades,vith little variation within each clade. In the present study, we used two different approaches to assess the genetic variation among biogeographically distinct vestimentiferan symbionts, DNA sequences were obtained for the noncoding, internal transcribed spacer (ITS) regions of the rRNA operons of symbionts associated with six different genera of vestimentiferan tubeworms. ITS sequences from endosymbionts of host genera collected …
Structure Of A Rat Α1-Macroglobulin Receptor-Binding Domain Dimer, Tsan Xiao, Dianne L. Decamp, Stephen R. Sprang
Structure Of A Rat Α1-Macroglobulin Receptor-Binding Domain Dimer, Tsan Xiao, Dianne L. Decamp, Stephen R. Sprang
Biological Sciences Faculty Publications
α-Macroglobulin inhibits a broad spectrum of proteinases by forming macromolecular cages inside which proteinases are cross-linked and trapped. Upon formation of a complex with proteinase, α-macroglobulin undergoes a large conformational change that results in the exposure of its receptor-binding domain (RBD). Engagement of this domain by α-macroglobulin receptor permits clearance of the α-macroglobulin: proteinase complex from circulation. The crystal structure of rat α1-macroglobulin RBD has been determined at 2.3 Å resolution. The RBD is composed of a nine-stranded β-sandwich and a single α-helix that has been implicated as part of the receptor binding site and that lies on …
Evidence For Microbial Fe(Iii) Reduction In Anoxic, Mining-Impacted Lake Sediments (Lake Coeur D’Alene, Idaho), David E. Cummings, Anthony W. March, Benjamin Bostick, Stefan Spring, Frank Caccavo Jr., Scott Fendorf, Frank Rosenzweig
Evidence For Microbial Fe(Iii) Reduction In Anoxic, Mining-Impacted Lake Sediments (Lake Coeur D’Alene, Idaho), David E. Cummings, Anthony W. March, Benjamin Bostick, Stefan Spring, Frank Caccavo Jr., Scott Fendorf, Frank Rosenzweig
Biological Sciences Faculty Publications
Mining-impacted sediments of Lake Coeur d'Alene, Idaho, contain more than 10% metals on a dry weight basis, approximately 80% of which is iron. Since iron (hydr)oxides adsorb toxic, ore-associated elements, such as arsenic, iron (hydr)oxide reduction may in part control the mobility and bioavailability of these elements. Geochemical and microbiological data were collected to examine the ecological role of dissimilatory Fe(III)-reducing bacteria in this habitat. The concentration of mild-acid-extractable Fe(II) increased with sediment depth up to 50 g kg−1, suggesting that iron reduction has occurred recently. The maximum concentrations of dissolved Fe(II) in interstitial water (41 mg liter …