A5056674259- Microbial Community Ecology and Physiology
- Marine and coastal ecosystems
- Metabolomics and Mass Spectrometry Studies
- Isotope Analysis in Ecology
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
- Genomics and Phylogenetic Studies
- Mass Spectrometry Techniques and Applications
- Protist diversity and phylogeny
- Analytical chemistry methods development
- Oil Spill Detection and Mitigation
- Coral and Marine Ecosystems Studies
- Marine Sponges and Natural Products
- Ocean Acidification Effects and Responses
- Aquaculture disease management and microbiota
- Wastewater Treatment and Nitrogen Removal
- Atmospheric and Environmental Gas Dynamics
- Oceanographic and Atmospheric Processes
- Per- and polyfluoroalkyl substances research
- Amino Acid Enzymes and Metabolism
- Toxic Organic Pollutants Impact
- Algal biology and biofuel production
- Groundwater and Isotope Geochemistry
- Arctic and Antarctic ice dynamics
- Advanced Proteomics Techniques and Applications
Woods Hole Oceanographic Institution
2016-2025
Woodwell Climate Research Center
2014-2022
Oregon State University
2000-2006
Portland State University
2000-2001
Rutgers, The State University of New Jersey
2000
Response actions to the Deepwater Horizon oil spill included injection of ∼771,000 gallons (2,900,000 L) chemical dispersant into flow near seafloor. Prior this incident, no deepwater applications had been conducted, and thus data exist on environmental fate dispersants in deepwater. We used ultrahigh resolution mass spectrometry liquid chromatography with tandem (LC/MS/MS) identify quantify one key ingredient dispersant, anionic surfactant DOSS (dioctyl sodium sulfosuccinate), Gulf Mexico...
Dissolved organic matter (DOM) in the oceans is one of largest pools reduced carbon on Earth, comparable size to atmospheric CO 2 reservoir. A vast number compounds are present DOM, and they play important roles all major element cycles, contribute storage ocean, support marine ecosystems, facilitate interactions between organisms. At heart DOM cycle lie molecular-level relationships individual members ocean microbiome that produce consume them. In past, these connections have eluded clear...
Ultrahigh resolution mass spectrometry, such as Fourier transform ion cyclotron resonance spectrometry (FT ICR MS), can resolve thousands of molecular ions in complex organic matrices. A Compound Identification Algorithm (CIA) was previously developed for automated elemental formula assignment natural matter (NOM). In this work, we describe software Formularity with a user-friendly interface CIA function and newly search Isotopic Pattern (IPA). While assigns formulas compounds containing C,...
ABSTRACT The phylogenetic diversity was determined for a microbial community obtained from an in situ growth chamber placed on deep-sea hydrothermal vent the Mid-Atlantic Ridge (23°22′ N, 44°57′ W). deployed 5 days, and temperature within gradually decreased 70 to 20°C. Upon retrieval of chamber, DNA extracted small-subunit rRNA genes (16S rDNA) were amplified by PCR using primers specific Archaea or Bacteria domain cloned. Unique rDNA sequences identified restriction fragment length...
Summary Although bacterioplankton and phytoplankton are generally perceived as closely linked in marine systems, specific interactions between discrete populations largely unknown. However, measurements of distributions during blooms may indicate microbial lineages that responding to populations, potentially controlling them by producing allelopathic compounds. Here we use a comprehensive molecular approach identify, characterize quantify community responses an Oregon coast diatom bloom....
Summary Photoautotrophic plankton in the surface ocean release organic compounds that fuel secondary production by heterotrophic bacteria. Here we show an abundant marine cyanobacterium, S ynechococcus elongatus , contributes a variety of nitrogen‐rich and sulfur‐containing to dissolved matter. A combination targeted untargeted metabolomics genomic tools was used characterize intracellular extracellular metabolites . Aromatic compounds, such as 4‐hydroxybenzoic acid phenylalanine, well...
ABSTRACT We evaluated whether bacteria with higher cell-specific nucleic acid content (HNA) or an active electron transport system, i.e., positive for reduction of 5-cyano-2,3-ditolyl tetrazolium chloride (CTC), were responsible the bulk bacterioplankton metabolic activity. also examined phylogenetic diversity HNA and CTC-positive cells differed from Bacteria low (LNA). Bacterial assemblages sampled both in eutrophic shelf waters mesotrophic offshore Oregon coastal upwelling region....
The Deepwater Horizon oil spill was one of the largest spills in history, and fate this within Gulf Mexico ecosystem remains to be fully understood. goal study—conducted mid-June 2010, approximately two months after began—was understand key role that microbes would play degradation offshore oligotrophic surface waters near site. As utilization organic carbon by bacteria had been previously shown phosphorus limited, we hypothesized unable rapidly utilize released from Macondo well. Although...
We investigated the patterns in bacterial growth, production, respiration, growth efficiency (BGE), and leucine respiration C‐to‐leucine yield (i.e., conversion factor [CF]) along a transect off coast of Oregon. Plankton averaged 1.15 ± 0.16 mg C L −1 h , peaking coastal upwelling region. The filtered fraction, which was dominated by biomass, accounted for 79% total respiration. different approaches that we used converged to an average BGE 13% 1%, with peaks over 20% more productive areas...
Phosphorus loads are strongly associated with the severity of harmful algal blooms in Lake Erie, a Great situated between United States and Canada. Inorganic total phosphorus measurements have historically been used to estimate nonpoint point source contributions, from contributing watersheds organic often neglected. Here, we ultrahigh resolution mass spectrometry characterize dissolved matter specifically composition several nutrient pollutant materials aqueous samples Erie tributary. We...
Abstract Marine dissolved organic matter (DOM) varies in its recalcitrance to rapid microbial degradation. DOM of varying can be exported from the ocean surface depth by subduction or convective mixing and oxidized over months decades deeper seawater. Carboxyl‐rich alicyclic molecules (CRAM) are characterized as a major component recalcitrant throughout oceanic water column. The oxidation CRAM‐like compounds may depend on specific bacterioplankton lineages with oxidative enzymes capable...
It has been hypothesized that the abundant heterotrophic ocean bacterioplankton in SAR202 clade of phylum Chloroflexi evolved specialized metabolisms for oxidation organic compounds are resistant to microbial degradation via common metabolic pathways. Expansions paralogous enzymes were reported and implicated hypothetical metabolism involving monooxygenase dioxygenase enzymes. In proposed schemes, paralogs serve purpose diversifying range molecules cells can utilize. To further explore...
Abstract As coral reef ecosystems experience unprecedented change, effective monitoring of features supports management, conservation, and intervention efforts. Omic techniques show promise in quantifying key components including dissolved metabolites microorganisms that may serve as invisible sensors for ecosystem dynamics. Dissolved are released by organisms transferred among microorganisms, acting chemical currencies contributing to nutrient cycling signaling on reefs. Here, we applied...
The diversity associated with a microbial mat sample collected from deep-sea hydrothermal vent on the Southern East Pacific Rise was determined using molecular phylogenetic approach based comparison of sequences small subunit ribosomal RNA gene (16S rDNA). DNA extracted and 16S rDNA amplified by PCR. Sixteen different phylotypes were identified restriction fragment length polymorphism analysis; four later as putative chimeras. Analysis placed all within Proteobacteria. majority (98%) most...
Marine microbes are critical players in the global carbon cycle, affecting both reduction of inorganic and remineralization reduced organic compounds back to dioxide. Members microbial consortia all depend on marine dissolved matter (DOM) turn, affect molecules present this heterogeneous pool. Our understanding DOM produced by is biased towards single species laboratory cultures or simplified field incubations, which exclude large phototrophs protozoan grazers. Here we explore...
Metabolomics is the study of small molecules, or ‘metabolites’, that are end products biological processes. While -omics technologies such as genomics, transcriptomics, and proteomics measure metabolic potential organisms, metabolomics provides detailed information on organic compounds produced during metabolism found within cells in environment. Improvements analytical techniques have expanded our understanding developments computational tools made data accessible to a broad segment...
Abstract Marine sinking particles transport carbon from the surface and bury it in deep‐sea sediments, where can be sequestered on geologic time scales. The combination of ocean food web that produces these particle‐associated microbial community degrades them creates a complex set variables control organic matter cycling. We use targeted metabolomics to characterize suite small biomolecules, or metabolites, compare their metabolite composition suspended euphotic zone which they are likely...
Marine dissolved organic matter (DOM) has long been recognized as a large and dynamic component of the global carbon cycle. Yet, DOM is chemically varied complex these attributes present challenges to researchers interested in addressing questions about role biogeochemical cycles.Organic extracts from seawater were analyzed by direct infusion with electrospray ionization into Fourier transform ion cyclotron resonance mass spectrometer. Network analysis was used quantify number chemical...