Use of Nitrogen-15-Enriched Escherichia coli as a Bacterial Tracer in Karst Aquifers.

Karst aquifers are susceptible to contamination by microorganisms, but relatively few studies have used bacteria as tracers. We demonstrate the utility of Escherichia coli enriched in the stable isotope nitrogen-15 ( N) as a novel bacterial tracer. Nonpathogenic E.

Precipitation influences on uptake of a global pollutant by a coastal avian species.

Climatic variation, including precipitation amounts and timing, has been linked to abundance and breeding success of many avian species. Less studied, but also of significance, is the consequence of climatic variability on the exposure and uptake of nutrients and contaminants by wildlife. The authors examined mercury (Hg) concentrations in nestling wood stork feathers in a coastal setting over a 16-yr period to understand the influence of rainfall amounts on Hg transfer by parental provisioning relative to habitat use, assuming differential bioavailability of Hg within freshwater and saltwater habitat types.

Mercury concentrations in nestling wading birds relative to diet in the southeastern United States: a stable isotope analysis.

Mercury (Hg) is a ubiquitous environmental contaminant that is transferred trophically through aquatic and terrestrial food webs. To better understand the routes of Hg uptake in organisms that rely on both aquatic and terrestrial food resources, we analyzed feather and down samples from nestling wading birds of varying trophic positions in both inland and coastal colonies. We used stable nitrogen and carbon isotope analyses to evaluate trophic positions of individual species (δ(15)N) and differences in foraging habitat use (δ(13)C).

Comparative geochemical and microbiological characterization of two thermal pools in the Uzon Caldera, Kamchatka, Russia.

Arkashin Schurf (Arkashin) and Zavarzin Spring (Zavarzin), two active thermal pools in the Uzon Caldera, Kamchatka, Russia, were studied for geochemical and microbiological characterization. Arkashin, the smaller of the two pools, had broader temperature and pH ranges, and the sediments had higher concentrations of total As (4,250 mg/kg) relative to Zavarzin (48.9 mg/kg).

Mercury contamination in turtles and implications for human health.

Mercury contamination threatens many ecosystems worldwide. Methylmercury bioaccumulates at each trophic level, and biomagnifies within individuals over time. Long-lived turtles often occupy high trophic positions and are likely to accumulate mercury in contaminated habitats.

Mesoscale patterns of altitudinal tenancy in migratory wood warblers inferred from stable carbon isotopes.

We analyzed carbon isotope ratios (delta13C) of liver and pectoral muscle of Black-throated Blue Warblers (Dendroica caerulescens) to provide a mesoscale perspective on altitudinal tenancy in the Appalachian Mountains, North Carolina, U.S.A.

Caldanaerovirga acetigignens gen. nov., sp. nov., an anaerobic xylanolytic, alkalithermophilic bacterium isolated from Trego Hot Spring, Nevada, USA.

An anaerobic thermophilic bacterium, designated strain JW/SA-NV4(T), was isolated from a xylan-supplemented enrichment culture from Trego hot spring located within the Black Rock Desert (NV, USA). Cells were generally straight or slightly bent rod-shaped, 0.4-0.

Desulfosporosinus youngiae sp. nov., a spore-forming, sulfate-reducing bacterium isolated from a constructed wetland treating acid mine drainage.

Strain JW/YJL-B18(T), a spore-forming, sulfate-reducing bacterium, was isolated from constructed wetland sediment. Cells were curved rods, 0.7-1.

Thermoanaerobacter uzonensis sp. nov., an anaerobic thermophilic bacterium isolated from a hot spring within the Uzon Caldera, Kamchatka, Far East Russia.

Several strains of heterotrophic, anaerobic thermophilic bacteria were isolated from hot springs of the Uzon Caldera, Kamchatka, Far East Russia. Strain JW/IW010(T) was isolated from a hot spring within the West sector of the Eastern Thermal field, near Pulsating Spring in the Winding Creek area. Cells of strain JW/IW010(T) were straight to slightly curved rods, 0.

Global occurrence of archaeal amoA genes in terrestrial hot springs.

Despite the ubiquity of ammonium in geothermal environments and the thermodynamic favorability of aerobic ammonia oxidation, thermophilic ammonia-oxidizing microorganisms belonging to the crenarchaeota kingdom have only recently been described. In this study, we analyzed microbial mats and surface sediments from 21 hot spring samples (pH 3.4 to 9.

Description of Caldalkalibacillus uzonensis sp. nov. and emended description of the genus Caldalkalibacillus.

Strain JW/WZ-YB58T, a thermophilic (42-64 degrees C), aerobic, alkalitolerant (pH25 degrees C 6.4-9.7), heterotrophic, sporulating, retarded-peritrichously flagellated and slightly curved rod-shaped bacterium, was isolated from the hot spring Zarvarzin II in the East Thermal Field of the Uzon Caldera, Kamchatka (Far East Russia).

Factors controlling the distribution of archaeal tetraethers in terrestrial hot springs.

Glycerol dialkyl glycerol tetraethers (GDGTs) found in hot springs reflect the abundance and community structure of Archaea in these extreme environments. The relationships between GDGTs, archaeal communities, and physical or geochemical variables are underexamined to date and when reported often result in conflicting interpretations. Here, we examined profiles of GDGTs from pure cultures of Crenarchaeota and from terrestrial geothermal springs representing a wide distribution of locations, including Yellowstone National Park (United States), the Great Basin of Nevada and California (United States), Kamchatka (Russia), Tengchong thermal field (China), and Thailand.

Influence of feeding ecology on blood mercury concentrations in four species of turtles.

Mercury is a relatively well-studied pollutant because of its global distribution, toxicity, and ability to bioaccumulate and biomagnify in food webs: however, little is known about bioaccumulation and toxicity of Hg in turtles. Total Hg (THg) concentrations in blood were determined for 552 turtles representing four different species (Chelydra serpentina, Sternotherus odoratus, Chrysemys picta, and Pseudemys rubriventris) from a Hg-contaminated site on the South River (VA, USA) and upstream reference sites. Methylmercury and Se concentrations also were determined in a subset of samples.

Bioaccumulation of trace elements in omnivorous amphibian larvae: implications for amphibian health and contaminant transport.

Despite the influence that amphibians have on the flow of energy and nutrients in ecological systems, the role that amphibians play in transporting contaminants through food webs has received very little attention. This study was undertaken to investigate bioaccumulation of trace elements in amphibians relative to other small aquatic organisms in a contaminated wetland. We collected bullfrog larvae (Rana catesbeiana) along with three other species of small vertebrates and four species of invertebrates from a site contaminated with a wide array of trace elements and analyzed them for trace element concentrations and stable nitrogen and carbon isotope composition.

Clostridium aciditolerans sp. nov., an acid-tolerant spore-forming anaerobic bacterium from constructed wetland sediment.

An obligately anaerobic, spore-forming, moderately acid-tolerant bacterium, strain JW/YJL-B3T, was isolated from a sediment sample from a constructed wetland system receiving acid sulfate water. Based on 16S rRNA gene sequence analysis, the isolate belonged to the Firmicutes branch with Clostridium drakei SL1T (96.2 % gene sequence similarity) as its closest relative.

Gracilibacter thermotolerans gen. nov., sp. nov., an anaerobic, thermotolerant bacterium from a constructed wetland receiving acid sulfate water.

An obligatorily anaerobic, thermotolerant, asporogenic bacterium, strain JW/YJL-S1(T), was isolated from a sediment sample of a constructed wetland system receiving acid sulfate water (pH 1.6-3.0).

Effect of in ovo exposure to PCBs and Hg on Clapper Rail bone mineral chemistry from a contaminated salt marsh in coastal Georgia.

The effect of Hg and PCBs (Aroclor 1268) on bone characteristics was investigated in a population of Clapper Rails (Rallus longirostris) inhabiting contaminated and unimpacted estuarine marsh systems in coastal Georgia. Exposure to contaminants did not affect the length or weight of leg bones, but it significantly altered the chemical composition of the bone. Specifically, bone in the contaminated site had a higher Ca to P, and lower carbonate and acid phosphate content.

Isolation and partial characterization of proteins involved in maternal transfer of selenium in the western fence lizard (Sceloporus occidentalis).

Selenium from dietary exposure is efficiently transferred from mother to offspring in oviparous vertebrates, where it can cause severe teratogenic effects. We isolated and partially characterized proteins involved in maternal transfer of selenium in the oviparous lizard Sceloporus occidentalis using size-exclusion chromatography, inductively coupled plasma-mass spectrometry, and polyacrylamide gel electrophoresis. Selenium from dietary selenomethionine exposure was incorporated into at least three egg proteins.

Thermalkalibacillus uzonensis gen. nov. sp. nov, a novel aerobic alkali-tolerant thermophilic bacterium isolated from a hot spring in Uzon Caldera, Kamchatka.

A novel thermophilic, alkali-tolerant, and CO-tolerant strain JW/WZ-YB58(T) was isolated from green mat samples obtained from the Zarvarzin II hot spring in the Uzon Caldera, Kamchatka (Far East Russia). Cells were Gram-type and Gram stain-positive, strictly aerobic, 0.7-0.

Shifts in relative tissue delta15N values in snowy egret nestlings with dietary mercury exposure: a marker for increased protein degradation.

Shifts in tissue nitrogen isotope composition may be a more sensitive general indicator of stress than measurement of high-turnover defensive biomolecules such as metallothionein and glutathione. As a physical resource transmitted along the trophic web, perturbations in protein nitrogen metabolism may also help resolve issues concerning the effects of contaminants on organisms and their consequential hierarchical linkages in ecotoxicology. Snowy egret nestlings (Egretta thula) fed mercury-contaminated diets of constant nitrogen isotope composition exhibited increased relative delta15N values in whole liver (p = 0.

Thermosediminibacter oceani gen. nov., sp. nov. and Thermosediminibacter litoriperuensis sp. nov., new anaerobic thermophilic bacteria isolated from Peru Margin.

A new group of anaerobic thermophilic bacteria was isolated from enrichment cultures obtained from deep sea sediments of Peru Margin collected during Leg 201 of the Ocean Drilling Program. A total of ten isolates were obtained from cores of 1-2 m below seafloor (mbsf) incubated at 60 degrees C: three isolates came from the sediment 426 m below sea level with a surface temperature of 9 degrees C (Site 1227), one from 252 m below sea level with a temperature of 12 degrees C (Site 1228), and six isolates under sulfate-reducing condition from the lower slope of the Peru Trench (Site 1230). Strain JW/IW-1228P from the Site 1228 and strain JW/YJL-1230-7/2 from the Site 1230 were chosen as representatives of the two identified clades.

Stable isotope signature of philopatry and dispersal in a migratory songbird.

Stable isotope analysis is widely promoted as a practical method for tracing the geographic origins of migratory birds. However, the extent to which geospatial patterns of isotope ratios in avian tissues are influenced by age-specific, altitudinal, and temporal factors remains largely unexplored. We measured carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) isotope ratios in feathers of black-throated blue warblers (Dendroica caerulescens) breeding along a relatively steep altitudinal gradient in the Appalachian Mountains to evaluate the effects of altitude and year on the isotopic signatures of yearling (first breeding season) and older males (>2 years).

Otolith delta 18O record of mid-Holocene sea surface temperatures in Peru.

Peruvian sea catfish (Galeichthys peruvianus) sagittal otoliths preserve a record of modern and mid-Holocene sea surface temperatures (SSTs). Oxygen isotope profiles in otoliths excavated from Ostra [6010 +/- 90 years before the present (yr B.P.