Search Constraints

Start Over
Filtering by: Advisor Hawkes, Stephen J. Remove constraint Advisor: Hawkes, Stephen J. Degree Level Doctoral Remove constraint Degree Level: Doctoral License All rights reserved Remove constraint License: All rights reserved

Search Results

  • Outliers: The Unusual Characteristics of Marine Carbon-Oxidizing Bacterial Cells Adapted to Oligotrophic Conditions

    Creator:
    Noell, Stephen E.
    Abstract:
    Oligotrophic bacteria are adapted to low nutrient concentrations. As most of the ocean is oligotrophic (low in nutrients), oligotrophic bacteria thrive in the ocean and make up the majority of planktonic cells. Because of this, oligotrophs are crucial to oceanic nutrient cycles. However, marine oligotrophic bacteria are dwarfed by their...
    Resource Type:
    Dissertation
    Full Text:
    : ______________________________________________________ Stephen J. Giovannoni ABSTRACT Oligotrophic bacteria are adapted to low nutrient

  • Single-Cell Genomics of Uncultivated Marine Bacteria

    Creator:
    Landry, Zachary
    Abstract:
    Historically, the difficulty of obtaining pure cultures of abundant marine microbial plankton has an obstacle to reconstructing the underlying mechanisms of biogeochemistry in the ocean. While a number of dominant marine species from the ocean surface have been cultured, the dominant microbial plankton of the dark ocean proved far more...
    Resource Type:
    Dissertation
    Full Text:
    : ______________________________________________________ Stephen Giovannoni Historically, the difficulty of obtaining pure cultures of abundant marine

  • Metabolism of one carbon (C1) and methylated compounds in SAR11 bacteria

    Creator:
    Sun, Jing
    Abstract:
    SAR11 Alphaproteobacteria are the most abundant aerobic chemoheterotrophs in ocean surface waters. Previous studies have indicated SAR11 cells play an important role in marine carbon cycling and consume up to half of some common dissolved organic compounds, such as amino acids. During sequencing of the first SAR11 genome, genes for...
    Resource Type:
    Dissertation
    Full Text:
    in SAR11 Bacteria Abstract approved: Stephen J. Giovannoni SAR11 Alphaproteobacteria are

  • Genome-enabled investigation of the minimal growth requirements andphosphate metabolism for Pelagibacter marine bacteria

    Creator:
    Carini, Paul J.
    Abstract:
    Members of the SAR11 clade of heterotrophic α-proteobacteria are ubiquitous and abundant in the world's oceans where they are thought to play a pivotal role in the global carbon cycle. The first SAR11 bacterium cultivated in vitro, 'Candidatus Pelagibacter ubique' HTCC1062 (Ca. P. ubique), was isolated by dilution into sterile...
    Resource Type:
    Dissertation
    Full Text:
    Phosphate Metabolism for Pelagibacter Marine Bacteria Abstract approved: Stephen J. Giovannoni

  • Culturing uncultured environmental microorganisms

    Creator:
    Connon, Stephanie A.
    Abstract:
    Research on natural environments, over the last decade, is replete with microbial diversity studies that used culture-independent approaches. The cloning and sequencing of the 16S rRNA genes has been the driving force in the expansion of awareness about the great diversity of previously undiscovered microorganisms. Well-known uncultured groups of microorganisms...
    Resource Type:
    Dissertation
    Full Text:
    Redacted for privacy ACKNOWLEDGMENTS I thank Stephen J. Giovannoni and Lewis Semprini for their

  • Microbial diversity, metabolic potential, and transcriptional activity along the inner continental shelf of the Northeast Pacific Ocean

    Creator:
    Bertagnolli, Anthony D.
    Abstract:
    Continental shelves located along eastern boundary currents occupy relatively small volumes of the world’s oceans, yet are responsible for a large proportion of global primary production. The Oregon coast is among these ecosystems. Recent analyses of dissolved oxygen at shallow depths in the water column has suggested increasing episodes of...
    Resource Type:
    Dissertation
    Full Text:
    : _____________________________________________________ Stephen J. Giovannoni Continental shelves located along eastern boundary currents occupy

  • Marine bacterioplankton abundances and distributions

    Creator:
    Morris, Robert M.
    Abstract:
    Microorganisms play key roles in ocean biogeochemistry. However, several predominant groups of uncultured bacterioplankton thought to contribute to important biogeochemical processes in the oceans are known primarily from gene cloning studies. Although these studies have greatly expanded our view of microbial diversity in the oceans, they are not quantitative and...
    Resource Type:
    Dissertation
    Full Text:
    ', Kevin L. Vergin', William A. Siebold1, Craig A. Carlson2, and Stephen J. Giovannoni' 'Department of

  • The proteomic and transcriptomic responses to iron, sulfur, and nitrogen limitation in the abundant marine bacterium Candidatus Pelagibacter ubique

    Creator:
    Smith, Daniel P.
    Abstract:
    Batch cultures of Candidatus Pelagibacter ubique were grown under iron-, organosulfur-, and nitrogen-limiting conditions to understand how this ubiquitous marine bacterium responds to and interacts with environments where growth is limited by the availability of these nutrients. Global gene expression was monitored using microarrays and quantitative mass spectrometry to observe...
    Resource Type:
    Dissertation
    Full Text:
    Abstract approved: ___________________________________________________ Stephen J. Giovannoni Batch

  • Proteomic analyses of marine bacteria

    Creator:
    Sowell, Sarah M.
    Abstract:
    Proteins are the metabolic machines of the cell and as such, the study of proteins could illuminate the dominant biological activities that are occurring within cells and reveal how an organism interacts with its environment. Here, we used proteomic techniques to study the abundant marine bacterium SAR11 both as an...
    Resource Type:
    Dissertation
    Full Text:
    Abstract approved: Douglas F. Barofsky Stephen J. Giovannoni Proteins are the metabolic

  • Prokaryotes associated with marine crust

    Creator:
    Mason, Olivia Underwood
    Abstract:
    Oceanic crust covers nearly 70% of the Earth's surface, of which, the upper, sediment layer is estimated to harbor substantial microbial biomass. Marine crust; however, extends several kilometers beyond this surficial layer, and includes the basalt and gabbro layers. In particular, the basalt layer has high permeabilities which allows for...
    Resource Type:
    Dissertation
    Full Text:
    : _______________________________________________ Stephen J. Giovannoni Martin R. Fisk Oceanic crust covers nearly 70% of the