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Full-Text Articles in Life Sciences
Occurrence Of Lysogenic Bacteria In Marine Microbial Communities As Determined By Prophage Induction, Sunny C. Jiang, John H Paul
Occurrence Of Lysogenic Bacteria In Marine Microbial Communities As Determined By Prophage Induction, Sunny C. Jiang, John H Paul
Marine Science Faculty Publications
Viruses are abundant and dynamic members of the marine microbial community, and it is important to understand their role in the ecology of natural microbial populations. We have previously found lysogenic bacteria to be a significant proportion (43%) of the cultivable heterotrophic microbial population. As the majority of marine bacteria are not cultivable using standard plating methods, we measured the proportion of marine lysogenic bacteria in natural communities by prophage induction. Mitomycin C, UV radiation, sunlight, temperature and pressure were used to induce prophage in lysogenic bacteria from estuarine, coastal and oligotrophic offshore environments. To determine if hydrocarbon pollutants may …
Evaluation Of Sampling Resolution In Coral Stable Isotope Records: A Case Study Using Records From New Caledonia And Tarawa, Terrence M. Quinn, Frederick W. Taylor, Thomas J. Crowley, Suzanne M. Link
Evaluation Of Sampling Resolution In Coral Stable Isotope Records: A Case Study Using Records From New Caledonia And Tarawa, Terrence M. Quinn, Frederick W. Taylor, Thomas J. Crowley, Suzanne M. Link
Marine Science Faculty Publications
We have generated a 40‐year‐long, monthly stable isotope record from a Porites lutea coral collected offshore of Amedee, New Caledonia (22°S, 167°E) to investigate the relation between sampling resolution in coral isotope studies and retrieval of sea‐surface environmental information. We interpret the high correlation between our oxygen isotope record and a twenty‐year long sea‐surface temperature record at the monthly timescale (r=0.88) to indicate that our coral isotope record is an accurate monitor of environmental conditions offshore of Amedee. The character of the signal and the percent variance explained in the record at the annual band, at the quasi‐biennial oscillation band …
Nitrogen Fixation Within A Tropical Upwelling Ecosystem: Evidence For A Redfield Budget Of Carbon/Nitrogen Cycling By The Total Phytoplankton Community, John J. Walsh
Marine Science Faculty Publications
Recent measurements and paradigms suggest that (1) the uptake of dissolved carbon and nitrate by phytoplankton may be greater than the Redfield ratio of 6.6 and (2) the oceans may be loosing nitrogen from an imbalance in the global rates of nitrogen fixation and denitrification. An analysis of concurrent ΔDIC/ΔNO3 depletion ratios within the Venezuelan and Peruvian upwelling ecosystems, indeed, suggests that values of 10.1–28.6 may pertain to these tropical eutrophic habitats. Nitrogen fixation may provide a Redfield balance in at least the former system, with 34–77% of the new production attributed to assimilation of N2. Independent …
Regulation Of Ribulose Bisphosphate Carboxylase Gene Expression In Natural Phytoplankton Communities .1. Diel Rhythms, S. L. Pichard, L. Campbell, J. B. Kang, F. Robert Tabita, John H Paul
Regulation Of Ribulose Bisphosphate Carboxylase Gene Expression In Natural Phytoplankton Communities .1. Diel Rhythms, S. L. Pichard, L. Campbell, J. B. Kang, F. Robert Tabita, John H Paul
Marine Science Faculty Publications
Marine phytoplankton fix carbon dioxide primarily through the action of ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO), the first enzyme in the Calvin Cycle. Although the regulation of this enzyme has been studied in algal cultures and higher plants, little is known regarding RubisCO regulation in natural phytoplankton populations. To determine if natural communities of phytoplankton utilize transcriptional regulation to control RubisCO expression, we investigated the diel relationship between 14C carbon fixation and RubisCO large subunit (rbcL) transcript levels, rbcL DNA, chlorophyll a, autofluorescent cell counts and bacterial direct counts for natural communities of the southeastern Gulf of Mexico. Studies …
High-Resolution (104) Years Deep-Sea Foraminiferal Stable Isotope Records Of The Eocene-Oligocene Climate Transition, James C. Zachos, Terrence M. Quinn, Karen A. Salamy
High-Resolution (104) Years Deep-Sea Foraminiferal Stable Isotope Records Of The Eocene-Oligocene Climate Transition, James C. Zachos, Terrence M. Quinn, Karen A. Salamy
Marine Science Faculty Publications
We have constructed high‐resolution (104– 105 years) benthic foraminiferal δ13C and δ18O records for the upper Eocene through lower Oligocene of two pelagic sequences, Deep Sea Drilling Project (DSDP) Site 522 in the Angola Basin, South Atlantic Ocean, and Ocean Drilling Program (ODP) Site 744 in the southern Indian Ocean. These records provide improved constraints on both the timing and magnitude of marine oxygen and carbon isotope events from 30 to 35 Ma. The oxygen isotope records indicate that the ubiquitous δ18O increase (Oi‐1), which marks the rapid expansion of continental ice sheets and a minimum of 3° to 4°C …