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Articles 1111 - 1140 of 1323

Full-Text Articles in Environmental Microbiology and Microbial Ecology

Molecular Assays For Detecting Aphanomyces Invadans In Ulcerative Mycotic Fish Lesions, Mw Vandersea, Rw Litaker, B Yonnish,, Et Al, H Kator, Et Al Feb 2006

Molecular Assays For Detecting Aphanomyces Invadans In Ulcerative Mycotic Fish Lesions, Mw Vandersea, Rw Litaker, B Yonnish,, Et Al, H Kator, Et Al

VIMS Articles

The pathogenic oomycete Aphanomyces invadans is the primary etiological agent in ulcerative mycosis, an ulcerative skin disease caused by a fungus-like agent of wild and cultured fish. We developed sensitive PCR and fluorescent peptide nucleic acid in situ hybridization (FISH) assays to detect A. invadans. Laboratory-challenged killifish (Fundulus heteroclitus) were first tested to optimize and validate the assays. Skin ulcers of Atlantic menhaden (Brevoortia tyrannus) from populations found in the Pamlico and Neuse River estuaries in North Carolina were then surveyed. Results from both assays indicated that all of the lesioned menhaden (n = 50) collected in September 2004 were …

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Interactions Between Marine Snow And Heterotrophic Bacteria: Aggregate Formation And Microbial Dynamics, Hp Grossart, T Kiorboe, Kw Tang, Et Al Feb 2006

Interactions Between Marine Snow And Heterotrophic Bacteria: Aggregate Formation And Microbial Dynamics, Hp Grossart, T Kiorboe, Kw Tang, Et Al

VIMS Articles

Macroscopic aggregates (marine snow) contribute to new production and nutrient dynamics in the upper ocean and vertical fluxes of organic matter to the deep ocean. To test whether microorganisms play a significant role in phytoplankton aggregate formation we studied particle abundance and size as well as abundance, colonization behaviour, and community composition of bacteria during the growth of 2 marine diatoms (Thalassiosira weissflogii and Navicula sp.) under axenic and non-axenic conditions. Community composition of free-living and attached bacteria during phytoplankton growth and aggregation was studied by amplification of 16S rRNA gene fragments and denaturing gradient gel electrophoresis (DGGE). Our results …

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Densities Of Fecal Indicator Bacteria In Tidal Waters Of The Ballona Wetlands, Los Angeles County, California, John H. Dorsey Jan 2006

Densities Of Fecal Indicator Bacteria In Tidal Waters Of The Ballona Wetlands, Los Angeles County, California, John H. Dorsey

Center for Urban Resilience Scholarship

Densities of fecal indicator bacteria (FIB) represented by total coliforms, E. coli and enterococci were measured within tidal channels of the Ballona Wetlands (Los Angeles County) to see if the wetlands act as a sink or source for these bacteria and to measure increases in FIB densities during wet weather. Samples were collected on 10 days over a 1-yr period beginning February 2003 at four sites within the wetlands and one site in Ballona Creek opposite the west tide gate. Incoming flood and outgoing ebb tides were sampled during each sampling event at each station. Water from Ballona Creek may …

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Prevalence And Serovars Of Salmonella In The Feces Of Free-Ranging White-Tailed Deer (Odocoileus Virginianus) In Nebraska, David G. Renter, David P. Gnad, Jan M. Sargeant, Scott E. Hygnstrom Jan 2006

Prevalence And Serovars Of Salmonella In The Feces Of Free-Ranging White-Tailed Deer (Odocoileus Virginianus) In Nebraska, David G. Renter, David P. Gnad, Jan M. Sargeant, Scott E. Hygnstrom

School of Natural Resources: Faculty Publications

To determine the prevalence and serovars of Salmonella in free-ranging deer, we cultured feces from white-tailed deer (Odocoileus virginianus) harvested by hunters during a regular firearm season in southeastern Nebraska (USA). We recovered Salmonella from 5 (1%; 95% confidence interval: 0.37– 2.20%) of 500 samples and identified four different Salmonella enterica serovars [Litchfield (1), Dessau (1), Infantis (2), and Enteritidis (1)]. Although the prevalence of Salmonella in free-ranging deer appears to be low, the serovars recovered are known to be pathogenic to humans and animals.

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Effects Of Feed Additives And Mixed Eimeria Species Infection On Intestinal Microbial Ecology Of Broilers, M. E. Hume, S. Clemente-Hernandez, E. O. Oviedo Rondon Jan 2006

Effects Of Feed Additives And Mixed Eimeria Species Infection On Intestinal Microbial Ecology Of Broilers, M. E. Hume, S. Clemente-Hernandez, E. O. Oviedo Rondon

Faculty Publications

Evaluation of digestive microbial ecology is necessary to understand effects of growth-promoting feed. In the current study, the dynamics of intestinal microbial communities (MC) were examined in broilers fed diets supplemented with a combination of antibiotic (bacitracin methylene disalicylate) and ionophore (Coban 60), and diets containing 1 of 2 essential oil (EO) blends, Crina Poultry (CP) and Crina Alternate (CA). Five treatments were analyzed: 1) unmedicated uninfected control; 2) unmedicated infected control; 3) feed additives monensin (bacitracin methylene disalicylate) + monensin (Coban 60; AI); 4) EO blend CP; and 5) EO blend CA. Additives were mixed into a basal feed …

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Desiccation Responses And Survival Of Sinorhizobium Meliloti Usda 1021 In Relation To Growth Phase, Temperature, Chloride And Sulfate Availability, Jan A.C. Vriezen Dr., Frans J. Debruijn Dr., Klaus R. Nusslein Dr. Jan 2006

Desiccation Responses And Survival Of Sinorhizobium Meliloti Usda 1021 In Relation To Growth Phase, Temperature, Chloride And Sulfate Availability, Jan A.C. Vriezen Dr., Frans J. Debruijn Dr., Klaus R. Nusslein Dr.

Jan A.C. Vriezen Dr.

Aims: To identify physical and physiological conditions that affect the survival of Sinorhizobium meliloti USDA 1021 during desiccation. Methods and Results: An assay was developed to study desiccation response of S. meliloti USDA 1021 over a range of environmental conditions. We deter- mined the survival during desiccation in relation to (i) matrices and media, (ii) growth phase, (iii) temperature, and (iv) chloride and sulfate availability. Conclusions: This study indicates that survival of S. meliloti USDA 1021 during desiccation is enhanced: (i) when cells were dried in the stationary phase, (ii) with increasing drying temperature at an optimum of 37°C, and …

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Survival And Growth Of Two Heterotrophic Hydrothermal Vent Archaea, Pyrococcus Strain Gb-D And Thermococcus Fumicolans, Under Low Ph And High Sulfide Concentrations In Combination With High Temperature And Pressure Regimes, Virginia P. Edgcomb, Stephen J. Molyneaux, Simone Böer, Carl O. Wirsen, Mark Saito, Michael S. Atkins, Karen Lloyd, Andreas Teske Jan 2006

Survival And Growth Of Two Heterotrophic Hydrothermal Vent Archaea, Pyrococcus Strain Gb-D And Thermococcus Fumicolans, Under Low Ph And High Sulfide Concentrations In Combination With High Temperature And Pressure Regimes, Virginia P. Edgcomb, Stephen J. Molyneaux, Simone Böer, Carl O. Wirsen, Mark Saito, Michael S. Atkins, Karen Lloyd, Andreas Teske

Karen Lloyd

Growth and survival of hyperthermophilic archaea in their extreme hydrothermal vent and subsurface environments are controlled by chemical and physical key parameters. This study examined the effects of elevated sulfide concentrations, temperature, and acidic pH on growth and survival of two hydrothermal vent archaea (Pyrococcus strain GB-D and Thermococcus fumicolans) under high temperature and pressure regimes. These two strains are members of the Thermococcales, a family of hyperthermophilic, heterotrophic, sulfur-reducing archaea that occur in high densities at vent sites. As actively growing cells, these two strains tolerated regimes of pH, pressure, and temperature that were in most cases not tolerated …

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Heterotrophic Archaea Dominate Sedimentary Subsurface Ecosystems Off Peru, Jennifer F. Biddle, Julius S. Lipp, Karen Lloyd, Ketil B. Sørensen, Rika Anderson, Helen F. Fredericks, Marcus Elvert, Timothy J. Kelly, Daniel P. Schrag, Mitchell L. Sogin, Jean E. Brenchley, Andreas Teske, Christopher H. House, Kaw-Uwe Hinrichs Jan 2006

Heterotrophic Archaea Dominate Sedimentary Subsurface Ecosystems Off Peru, Jennifer F. Biddle, Julius S. Lipp, Karen Lloyd, Ketil B. Sørensen, Rika Anderson, Helen F. Fredericks, Marcus Elvert, Timothy J. Kelly, Daniel P. Schrag, Mitchell L. Sogin, Jean E. Brenchley, Andreas Teske, Christopher H. House, Kaw-Uwe Hinrichs

Karen Lloyd

Studies of deeply buried, sedimentary microbial communities and associated biogeochemical processes during Ocean Drilling Program Leg 201 showed elevated prokaryotic cell numbers in sediment layers where methane is consumed anaerobically at the expense of sulfate. Here, we show that extractable archaeal rRNA, selecting only for active community members in these ecosystems, is dominated by sequences of uncultivated Archaea affiliated with the Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group, whereas known methanotrophic Archaea are not detectable. Carbon flow reconstructions based on stable isotopic compositions of whole archaeal cells, intact archaeal membrane lipids, and other sedimentary carbon pools indicate that …

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Comparison Study Of Sediment Microbial Enzyme Activities To Biochemical Oxygen Demand, Nitrate Concentration, Phosphate Concentration In The Sediments Of A Fecally-Contaminated Stream In Northeast Tennessee Relative To Season And Land Use, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman Jan 2006

Comparison Study Of Sediment Microbial Enzyme Activities To Biochemical Oxygen Demand, Nitrate Concentration, Phosphate Concentration In The Sediments Of A Fecally-Contaminated Stream In Northeast Tennessee Relative To Season And Land Use, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman

ETSU Faculty Works

Microbial metabolism reacts quickly to environmental conditions. These reactions are dependent on the need for nutrients and respiration and can be measured using an assay of individual microbial enzyme activities (MEA’s). In this study, we measured MEA’s in the sediments of a stream in northeast Tennessee that had an approved fecal coliform Total Maximum Daily Load (TMDL). These values were compared to biochemical oxygen demand (BOD), phosphate concentration and nitrate concentration in the water column of this stream. Comparisons were grouped by season and land use. Stream sediments and water were collected monthly for one year and then quarterly for …

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Antibiotic Resistant And Coliform Bacteria In The Ohio River; 2002 To 2004, Lisa Marie Smith Jan 2006

Antibiotic Resistant And Coliform Bacteria In The Ohio River; 2002 To 2004, Lisa Marie Smith

Theses, Dissertations and Capstones

During 2002 and 2003 samples, collected every five miles along the Ohio River, were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, erythromycin resistant bacteria, tetracycline resistant bacteria, and fecal coliforms. During 2004 samples were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, sulfamethizole resistant bacteria, tetracycline resistant bacteria, Virginiamycin resistant bacteria, total coliforms, and Escherichia coli. The objectives of this study were to systematically collect data on fecal coliforms, E. coli, and antibiotic resistant bacteria in the Ohio River and its major tributaries; to determine if antibiotic resistance populations are correlated to each other or to coliforms; and …

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Determination Of Mrna Half-Lives In Candida Albicans Using Thiolutin As A Transcription Inhibitor, Bessie W. Kebaara, Lindsey E. Nielsen, Kenneth Nickerson, Audrey L. Atkin Jan 2006

Determination Of Mrna Half-Lives In Candida Albicans Using Thiolutin As A Transcription Inhibitor, Bessie W. Kebaara, Lindsey E. Nielsen, Kenneth Nickerson, Audrey L. Atkin

Kenneth Nickerson Papers

A method for determining mRNA half-lives in the polymorphic fungus Candida albicans is described. It employs growth in a defined medium, the inhibition of transcription with thiolutin (10–20 μg/mL), and quantitative Northern blotting. The method is effective for the A72, SC5314, and CAI-4 strains of C. albicans, and for mRNAs that have a wide variety of decay rates and steady-state abundances. The range of half-lives detected (from 4–168 min) shows that this method is effective for mRNAs with widely varying half-lives. The mRNA decay rates obtained are compared with those for orthologous mRNAs from Saccharomyces cerevisiae. This procedure …

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Comparison Of Microbial Water Quality Parameters Of Four Geographically Similar Creeks In Northeast Tennessee, Kimberlee K. Hall, L. K. Gallagher, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman Jan 2006

Comparison Of Microbial Water Quality Parameters Of Four Geographically Similar Creeks In Northeast Tennessee, Kimberlee K. Hall, L. K. Gallagher, Brian G. Evanshen, Kurt J. Maier, Phillip R. Scheuerman

ETSU Faculty Works

Four creeks within the Watauga River watershed in Northeast Tennessee are routinely monitored for water quality assessments. To identify sources and monitor remediation, Sinking Creek, Cash Hollow Creek, Buffalo Creek and Boones Creek are monitored for chemical and microbial parameters. These parameters include phosphates, nitrates, BOD and fecal coliforms. Sinking Creek is a tributary of the Watauga River with 10 miles of impaired water. Cash Hollow Creek enters the Watauga River at river mile 11.4 with 3.4 miles of impaired water. Boones Creek contains 18.6 impaired miles while the status of water quality in Buffalo Creek is not yet determined. …

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Toward A Conceptual And Operational Union Of Bacterial Systematics, Ecology, And Evolution, Frederick M. Cohan Dec 2005

Toward A Conceptual And Operational Union Of Bacterial Systematics, Ecology, And Evolution, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.

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Cyanobacterial Ecotypes In The Microbial Mat Community Of Mushroom Spring (Yellowstone National Park, Wyoming) As Species-Like Units Linking Microbial Community Composition, Structure And Function, D. M. Ward, M. M. Bateson, M. J. Ferris, M. Kuhl, A. Wieland, A. Koeppel, Frederick M. Cohan Dec 2005

Cyanobacterial Ecotypes In The Microbial Mat Community Of Mushroom Spring (Yellowstone National Park, Wyoming) As Species-Like Units Linking Microbial Community Composition, Structure And Function, D. M. Ward, M. M. Bateson, M. J. Ferris, M. Kuhl, A. Wieland, A. Koeppel, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.

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The Use Of Antibiotic Resistance Profiles To Access The Source Of Fecal Contamination In The Rowan County, Kentucky Watershed, Logan Harrison Burns Dec 2005

The Use Of Antibiotic Resistance Profiles To Access The Source Of Fecal Contamination In The Rowan County, Kentucky Watershed, Logan Harrison Burns

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Logan Harrison Burns on December 15, 2005.

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Effects Of Commercial Diazinon And Imidacloprid On Microbial Urease Activity In Soil And Sod, C. W. Ingram, Mark S. Coyne, David W. Williams Sep 2005

Effects Of Commercial Diazinon And Imidacloprid On Microbial Urease Activity In Soil And Sod, C. W. Ingram, Mark S. Coyne, David W. Williams

Plant and Soil Sciences Faculty Publications

Diazinon [O,O-diethyl O-2-isopropyl-6-methyl(pyrimidine-4-yl) phosphorothioate] and imidacloprid [1-(1-[6-chloro-3-pyridinyl]methyl)-N-nitro-2-imidazolidinimine] are applied to lawns for insect control simultaneously with nitrogenous fertilizers such as urea, but their potential effect on urease activity and nitrogen availability in turfgrass management has not been evaluated. Urease activity in enzyme assays, washed cell assays, and soil slurries was examined as a function of insecticide concentration. Intact cores from field sites were used to assess the effect of insecticide application on urease activity in creeping bentgrass (Agrostis palustris Huds.) and bluegrass (Poa pratensis L.) sod. Bacterial urease fromBacillus pasteurii and plant …

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Evolutionary Innovation: A Bone-Eating Marine Symbiosis, Shana K. Goffredi, Victoria J. Orphan, Greg W. Rouse, Linda Jahnke, Tsegeria Embaye, Kendra Turk, Ray Lee, Robert C. Vrijenhoek Aug 2005

Evolutionary Innovation: A Bone-Eating Marine Symbiosis, Shana K. Goffredi, Victoria J. Orphan, Greg W. Rouse, Linda Jahnke, Tsegeria Embaye, Kendra Turk, Ray Lee, Robert C. Vrijenhoek

Shana Goffredi

Symbiotic associations between microbes and invertebrates have resulted in some of the most unusual physiological and morphological adaptations that have evolved in the animal world. We document a new symbiosis between marine polychaetes of the genus Osedax and members of the bacterial group Oceanospirillales, known for heterotrophic degradation of complex organic compounds. These organisms were discovered living on the carcass of a grey whale at 2891 m depth in Monterey Canyon, off the coast of California. The mouthless and gutless worms are unique in their morphological specializations used to obtain nutrition from decomposing mammalian bones. Adult worms possess elaborate posterior …

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Ua3/9/5 Conservation Reserve Enhancement Program (Crep), Wku President's Office Aug 2005

Ua3/9/5 Conservation Reserve Enhancement Program (Crep), Wku President's Office

WKU Archives Records

Talking points used by WKU president Gary Ransdell regarding WKU's partnering with Conservation Reserve Enhancement Program.

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Fertilizer, Tillage, And Dairy Manure Contributions To Nitrate And Herbicide Leaching, C. S. Stoddard, John H. Grove, Mark S. Coyne, William O. Thom Jul 2005

Fertilizer, Tillage, And Dairy Manure Contributions To Nitrate And Herbicide Leaching, C. S. Stoddard, John H. Grove, Mark S. Coyne, William O. Thom

Plant and Soil Sciences Faculty Publications

Few studies have examined the water quality impact of manure use in no-tillage systems. A lysimeter study in continuous corn (Zea mays L.) was performed on Maury silt loam (fine, mixed, semiactive, mesic Typic Paleudalf) to evaluate the effect(s) of tillage (no-till [NT] and chisel-disk [CD]), nitrogen fertilizer rate (0 and 168 kg N ha−1), and dairy manure application timing (none, spring, fall, or fall plus spring) on NO3–N, atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine), and alachlor [2-chloro-2′-6′-diethyl-N-(methoxymethyl)acetanilide] concentrations in leachate collected at a 90-cm depth. Herbicides were highest immediately after application, declining to less …

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Susceptibility Of Biofilms To Bdellovibrio Bacteriovorus Attack, Daniel Kadouri, George A. O'Toole Jul 2005

Susceptibility Of Biofilms To Bdellovibrio Bacteriovorus Attack, Daniel Kadouri, George A. O'Toole

Dartmouth Scholarship

Biofilms are communities of microorganisms attached to a surface, and the growth of these surface attached communities is thought to provide microorganisms with protection against a range of biotic and abiotic agents. The capability of the gram-negative predatory bacterium Bdellovibrio bacteriovorus to control and reduce an existing Escherichia coli biofilm was evaluated in a static assay. A reduction in biofilm biomass was observed as early as 3 h after exposure to the predator, and an 87% reduction in crystal violet staining corresponding to a 4-log reduction in biofilm cell viability was seen after a 24-h exposure period. We observed that …

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Cellulose Utilization By Clostridium Thermocellum: Bioenergetics And Hydrolysis Product Assimilation, Yi-Heng P. Zhang, Lee R. Lynd May 2005

Cellulose Utilization By Clostridium Thermocellum: Bioenergetics And Hydrolysis Product Assimilation, Yi-Heng P. Zhang, Lee R. Lynd

Dartmouth Scholarship

The bioenergetics of cellulose utilization by Clostridium thermocellum was investigated. Cell yield and maintenance parameters, Y(X/ATP)True = 16.44 g cell/mol ATP and m = 3.27 mmol ATP/g cell per hour, were obtained from cellobiose-grown chemostats, and it was shown that one ATP is required per glucan transported. Experimentally determined values for G(ATP)P-T (ATP from phosphorolytic beta-glucan cleavage minus ATP for substrate transport, mol ATP/mol hexose) from chemostats fed beta-glucans with degree of polymerization (DP) 2-6 agreed well with the predicted value of (n-2)/n [corrected] (n = mean cellodextrin DP assimilated). A mean G(ATP)(P-T) value of 0.52 +/- 0.06 was calculated …

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Mycobacterium Pseudoshottsii Sp Nov., A Slowly Growing Chromogenic Species Isolated From Chesapeake Bay Striped Bass (Morone Saxatilis), Mw Rhodes, H Kator, Et Al, I Kaattari, Kimberly S. Reece, Wolfgang K. Vogelbein, Ca Ottinger May 2005

Mycobacterium Pseudoshottsii Sp Nov., A Slowly Growing Chromogenic Species Isolated From Chesapeake Bay Striped Bass (Morone Saxatilis), Mw Rhodes, H Kator, Et Al, I Kaattari, Kimberly S. Reece, Wolfgang K. Vogelbein, Ca Ottinger

VIMS Articles

A group of slowly growing photochromogenic mycobacteria was isolated from Chesapeake Bay striped bass (Morone saxatilis) during an epizootic of mycobacteriosis. Growth characteristics, acid-fastness and 16S rRNA gene sequencing results were consistent with those of the genus Mycobacterium, Biochemical reactions, growth characteristics and mycolic acid profiles (HPLC) resembled those of Mycobacterium shottsii, a non-pigmented mycobacterium also isolated during the same epizootic. Sequencing of the 16S rRNA genes, the gene encoding the exported repeated protein (erp) and the gene encoding the 65 kDa heat-shock protein (hsp65) and restriction enzyme analysis of the hsp65 gene demonstrated that this group of isolates is …

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Methanogen Diversity Evidenced By Molecular Characterization Of Methyl Coenzyme M Reductase A (Mcra) Genes In Hydrothermal Sediments Of The Guaymas Basin, Ashita Dhillon, Mark Lever, Karen Lloyd, Daniel B. Albert, Mitchell L. Sogin, Andreas Teske Mar 2005

Methanogen Diversity Evidenced By Molecular Characterization Of Methyl Coenzyme M Reductase A (Mcra) Genes In Hydrothermal Sediments Of The Guaymas Basin, Ashita Dhillon, Mark Lever, Karen Lloyd, Daniel B. Albert, Mitchell L. Sogin, Andreas Teske

Microbiology Publications and Other Works

The methanogenic community in hydrothermally active sediments of Guaymas Basin (Gulf of California, Mexico) was analyzed by PCR amplification, cloning, and sequencing of methyl coenzyme M reductase (mcrA) and 16S rRNA genes. Members of the Methanomicrobiales and Methanosarcinales dominated the mcrA and 16S rRNA clone libraries from the upper 15 cm of the sediments. Within the H2/CO2- and formate-utilizing family Methanomicrobiales, two mcrA and 16S rRNA lineages were closely affiliated with cultured species of the genera Methanoculleus and Methanocorpusculum. The most frequently recovered mcrA PCR amplicons within the Methanomicrobiales did not branch with any cultured genera. Within the nutritionally versatile …

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Methanogen Diversity Evidenced By Molecular Characterization Of Methyl Coenzyme M Reductase A (Mcra) Genes In Hydrothermal Sediments Of The Guaymas Basin, Ashita Dhillon, Mark Lever, Karen Lloyd, Daniel B. Albert, Mitchell L. Sogin, Andreas Teske Mar 2005

Methanogen Diversity Evidenced By Molecular Characterization Of Methyl Coenzyme M Reductase A (Mcra) Genes In Hydrothermal Sediments Of The Guaymas Basin, Ashita Dhillon, Mark Lever, Karen Lloyd, Daniel B. Albert, Mitchell L. Sogin, Andreas Teske

Karen Lloyd

The methanogenic community in hydrothermally active sediments of Guaymas Basin (Gulf of California, Mexico) was analyzed by PCR amplification, cloning, and sequencing of methyl coenzyme M reductase (mcrA) and 16S rRNA genes. Members of the Methanomicrobiales and Methanosarcinales dominated the mcrA and 16S rRNA clone libraries from the upper 15 cm of the sediments. Within the H2/CO2- and formate-utilizing family Methanomicrobiales, two mcrA and 16S rRNA lineages were closely affiliated with cultured species of the genera Methanoculleus and Methanocorpusculum. The most frequently recovered mcrA PCR amplicons within the Methanomicrobiales did not branch with any cultured genera. Within the nutritionally versatile …

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Characterization Of Microbial Activity, Mark P. Buttner, Patricia Cruz, Klaus J. Stetzenbach, Abe Van Luik, Thomas Williams, Amy J. Smiecinski Jan 2005

Characterization Of Microbial Activity, Mark P. Buttner, Patricia Cruz, Klaus J. Stetzenbach, Abe Van Luik, Thomas Williams, Amy J. Smiecinski

Publications (YM)

The overall goal of this study is to investigate the phenomena that affect the fate and transport of radionuclides in the environment. The objective of this task, “Characterization of Microbial Activity”, is to develop a molecular biological method for the characterization of the microbial population indigenous to the Yucca Mountain Project site, with emphasis in detection and measurement of species or groups of microorganisms that could be involved in actinide and/or metal reduction, and subsurface transport. Subtasks consist of QA planning and preparation, and literature review. This task is part of a cooperative agreement between the UNLV Research Foundation and …

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The Uptake Of Amino Acids By Microbes And Trees In Three Cold-Temperate Forests, Adrien C. Finzi, Sean T. Berthrong Jan 2005

The Uptake Of Amino Acids By Microbes And Trees In Three Cold-Temperate Forests, Adrien C. Finzi, Sean T. Berthrong

Scholarship and Professional Work - LAS

Amino acids are emerging as a critical component of the terrestrial N cycle, yet there is little understanding of amino acid cycling in temperate forests. This research studied the uptake and turnover of amino acid N by soil microbes and the capacity of forest trees to take up the amino acid glycine in comparison to NH4+ and NO3−. This research was conducted in three temperate forests located in northwest Connecticut, USA. The three forests differed in soil parent material and canopy tree species composition. At all three sites, amino acids were released from soil organic …

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Effects Of Dissolved Sulfide, Ph, And Temperature On Growth And Survival Of Marine Hyperthermophilic Archaea, Karen Lloyd, Virginia P. Edgcomb, Stephen J. Molyneaux, Simone Böer, Carl O. Wirsen, Michael S. Atkins, Andreas Teske Jan 2005

Effects Of Dissolved Sulfide, Ph, And Temperature On Growth And Survival Of Marine Hyperthermophilic Archaea, Karen Lloyd, Virginia P. Edgcomb, Stephen J. Molyneaux, Simone Böer, Carl O. Wirsen, Michael S. Atkins, Andreas Teske

Microbiology Publications and Other Works

The ability of metabolically diverse hyperthermophilic archaea to withstand high temperatures, low pHs, high sulfide concentrations, and the absence of carbon and energy sources was investigated. Close relatives of our study organisms, Methanocaldococcus jannaschii, Archaeoglobus profundus, Thermococcus fumicolans, and Pyrococcus sp. strain GB-D, are commonly found in hydrothermal vent chimney walls and hot sediments and possibly deeper in the subsurface, where highly dynamic hydrothermal flow patterns and steep chemical and temperature gradients provide an ever-changing mosaic of microhabitats. These organisms (with the possible exception of Pyrococcus strain GB-D) tolerated greater extremes of low pH, high sulfide concentration, and high temperature …

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Periodic Selection And Ecological Diversity In Bacteria, Frederick Cohan Jan 2005

Periodic Selection And Ecological Diversity In Bacteria, Frederick Cohan

Frederick M. Cohan

No abstract provided.

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Effects Of Dissolved Sulfide, Ph, And Temperature On Growth And Survival Of Marine Hyperthermophilic Archaea, Karen Lloyd, Virginia P. Edgcomb, Stephen J. Molyneaux, Simone Böer, Carl O. Wirsen, Michael S. Atkins, Andreas Teske Jan 2005

Effects Of Dissolved Sulfide, Ph, And Temperature On Growth And Survival Of Marine Hyperthermophilic Archaea, Karen Lloyd, Virginia P. Edgcomb, Stephen J. Molyneaux, Simone Böer, Carl O. Wirsen, Michael S. Atkins, Andreas Teske

Karen Lloyd

The ability of metabolically diverse hyperthermophilic archaea to withstand high temperatures, low pHs, high sulfide concentrations, and the absence of carbon and energy sources was investigated. Close relatives of our study organisms, Methanocaldococcus jannaschii, Archaeoglobus profundus, Thermococcus fumicolans, and Pyrococcus sp. strain GB-D, are commonly found in hydrothermal vent chimney walls and hot sediments and possibly deeper in the subsurface, where highly dynamic hydrothermal flow patterns and steep chemical and temperature gradients provide an ever-changing mosaic of microhabitats. These organisms (with the possible exception of Pyrococcus strain GB-D) tolerated greater extremes of low pH, high sulfide concentration, and high temperature …

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The Effects Of Dams In The Big Sandy Watershed Using A Novel Bacteria-Based Bioindicator Of Water Quality, Kathleen Riha Loughman Jan 2005

The Effects Of Dams In The Big Sandy Watershed Using A Novel Bacteria-Based Bioindicator Of Water Quality, Kathleen Riha Loughman

Theses, Dissertations and Capstones

During 2003, water samples from the Big Sandy watershed were collected in conjunction with the United States Army Corps of Engineers (USACE). Objectives were to determine the effects of dams on bacterial populations and to test a bioindicator of water quality based on antibiotic-resistant and fecal indicator bacteria. Thirty-five samples were taken each season within the Big Sandy Watershed, which includes six USACE dams. Total cultivable, ciprofloxacin-resistant, erythromycin-resistant, tetracycline- resistant, total coliform, and fecal coliform bacteria were enumerated. Data on water chemistry and physical parameters were collected by the USACE in the spring and summer seasons. Antibiotic-resistant bacteria and fecal …

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