9129767
MWYMG4GN
1
apa
50
date
desc
year
Barbeau
182
https://barbeaulab.ucsd.edu/wp-content/plugins/zotpress/
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Stow, P. R., Forsch, K. O., Thomsen, E., Naka, H., Haygood, M. G., Barbeau, K. A., & Butler, A. (2025). Stereospecific control of microbial growth by a combinatoric suite of chiral siderophores. Proceedings of the National Academy of Sciences, 122(10), e2423730122. https://doi.org/10.1073/pnas.2423730122
Manck, L. E., Coale, T. H., Stephens, B. M., Forsch, K. O., Aluwihare, L. I., Dupont, C. L., Allen, A. E., & Barbeau, K. A. (2024). Iron limitation of heterotrophic bacteria in the California Current System tracks relative availability of organic carbon and iron. The ISME Journal, 18(1), wrae061. https://doi.org/10.1093/ismejo/wrae061
Lampe, R. H., Coale, T. H., Forsch, K. O., Jabre, L. J., Kekuewa, S., Bertrand, E. M., Horák, A., Oborník, M., Rabines, A. J., Rowland, E., Zheng, H., Andersson, A. J., Barbeau, K. A., & Allen, A. E. (2023). Short-term acidification promotes diverse iron acquisition and conservation mechanisms in upwelling-associated phytoplankton. Nature Communications, 14(1), 7215. https://doi.org/10.1038/s41467-023-42949-1
Forsch, K. O., Fulton, K. C., Weiss, M. M., Krause, J. W., Stukel, M. R., & Barbeau, K. A. (2023). Iron Limitation and Biogeochemical Effects in Southern California Current Coastal Upwelling Filaments. Journal of Geophysical Research: Oceans, 128(11), e2023JC019961. https://doi.org/10.1029/2023JC019961
Forsch, K. O., Hahn-Woernle, L., Sherrell, R. M., Roccanova, V. J., Bu, K. X., Burdige, D., Vernet, M., & Barbeau, K. A. (2021). Seasonal dispersal of fjord meltwaters as an important source of iron and manganese to coastal Antarctic phytoplankton. Biogeosciences, 18(23), 6349–6375. https://doi.org/10.5194/bg-18-6349-2021
Moore, L. E., Heller, M. I., Barbeau, K. A., Moffett, J. W., & Bundy, R. M. (2021). Organic complexation of iron by strong ligands and siderophores in the eastern tropical North Pacific oxygen deficient zone. Marine Chemistry, 236, 16. https://doi.org/10.1016/j.marchem.2021.104021
Manck, L. E., Park, J., Tully, B. J., Poire, A. M., Bundy, R. M., Dupont, C. L., & Barbeau, K. A. (2021). Petrobactin, a siderophore produced by Alteromonas, mediates community iron acquisition in the global ocean. Isme Journal, 12. https://doi.org/10.1038/s41396-021-01065-y
Ruacho, A., Bundy, R. M., Till, C. P., Roshan, S., Wu, J. F., & Barbeau, K. A. (2020). Organic dissolved copper speciation across the US GEOTRACES equatorial Pacific zonal transect GP16. Marine Chemistry, 225. https://doi.org/10.1016/j.marchem.2020.103841
Pan, B. J., Vernet, M., Manck, L., Forsch, K., Ekern, L., Mascioni, M., Barbeau, K. A., Almandoz, G. O., & Orona, A. J. (2020). Environmental drivers of phytoplankton taxonomic composition in an Antarctic fjord. Progress in Oceanography, 183. https://doi.org/10.1016/j.pocean.2020.102295
Manck, L. E., Espinoza, J. L., Dupont, C. L., & Barbeau, K. A. (2020). Transcriptomic study of substrate-specific transport mechanisms for iron and carbon in the marine copiotroph Alteromonas macleodii. MSystems, 5(2). https://doi.org/10.1128/mSystems.00070-20
Stukel, M. R., & Barbeau, K. A. (2020). Investigating the nutrient landscape in a coastal upwelling region and its relationship to the biological carbon pump. Geophysical Research Letters, 47(6). https://doi.org/10.1029/2020gl087351
Coale, T. H., Moosburner, M., Horak, A., Obornik, M., Barbeau, K. A., & Allen, A. E. (2019). Reduction-dependent siderophore assimilation in a model pennate diatom. Proceedings of the National Academy of Sciences of the United States of America, 116(47), 23609–23617. https://doi.org/10.1073/pnas.1907234116
Meskhidze, N., Volker, C., Al-Abadleh, H. A., Barbeau, K., Bressac, M., Buck, C., Bundy, R. M., Croot, P., Feng, Y., Ito, A., Johansen, A. M., Landing, W. M., Mao, J. Q., Myriokefalitakis, S., Ohnemus, D., Pasquier, B., & Ye, Y. (2019). Perspective on identifying and characterizing the processes controlling iron speciation and residence time at the atmosphere-ocean interface. Marine Chemistry, 217. https://doi.org/10.1016/j.marchem.2019.103704
Jiang, M., Measures, C. I., Barbeau, K. A., Charette, M. A., Gille, S. T., Hatta, M., Kahru, M., Mitchell, B. G., Garabato, A. C. N., Reiss, C., Selph, K., & Zhou, M. (2019). Fe sources and transport from the Antarctic Peninsula shelf to the southern Scotia Sea. Deep-Sea Research Part I-Oceanographic Research Papers, 150. https://doi.org/10.1016/j.dsr.2019.06.006
Stukel, M. R., Kelly, T. B., Aluwihare, L. I., Barbeau, K. A., Goericke, R., Krause, J. W., Landry, M. R., & Ohman, M. D. (2019). The Carbon:(234)Thorium ratios of sinking particles in the California current ecosystem 1: relationships with plankton ecosystem dynamics. Marine Chemistry, 212, 1–15. https://doi.org/10.1016/j.marchem.2019.01.003
Chappell, P. D., Armbrust, E. V., Barbeau, K. A., Bundy, R. M., Moffett, J. W., Vedamati, J., & Jenkins, B. D. (2019). Patterns of diatom diversity correlate with dissolved trace metal concentrations and longitudinal position in the northeast Pacific coastal-offshore transition zone. Marine Ecology Progress Series, 609, 69–86. https://doi.org/10.3354/meps12810
Hogle, S. L., Dupont, C. L., Hopkinson, B. M., King, A. L., Buck, K. N., Roe, K. L., Stuart, R. K., Allen, A. E., Mann, E. L., Johnson, Z. I., & Barbeau, K. A. (2018). Pervasive iron limitation at subsurface chlorophyll maxima of the California Current. Proceedings of the National Academy of Sciences of the United States of America, 115(52), 13300–13305. https://doi.org/10.1073/pnas.1813192115
McQuaid, J. B., Kustka, A. B., Oborník, M., Horák, A., McCrow, J. P., Karas, B. J., Zheng, H., Kindeberg, T., Andersson, A. J., Barbeau, K. A., & Allen, A. E. (2018). Carbonate-sensitive phytotransferrin controls high-affinity iron uptake in diatoms. Nature, 555, 534. https://doi.org/10.1038/nature25982
Stuart, R. K., Bundy, R., Buck, K., Ghassemain, M., Barbeau, K., & Palenik, B. (2017). Copper toxicity response influences mesotrophic Synechococcus community structure. Environmental Microbiology, 19(2), 756–769. https://doi.org/10.1111/1462-2920.13630
Stukel, M. R., Aluwihare, L. I., Barbeau, K. A., Chekalyuk, A. M., Goericke, R., Miller, A. J., Ohman, M. D., Ruacho, A., Song, H., Stephens, B. M., & Landry, M. R. (2017). Mesoscale ocean fronts enhance carbon export due to gravitational sinking and subduction. Proceedings of the National Academy of Sciences of the United States of America, 114(6), 1252–1257. https://doi.org/10.1073/pnas.1609435114
Hogle, S. L., Brahamsha, B., & Barbeau, K. A. (2017). Direct heme uptake by phytoplankton-associated Roseobacter bacteria. MSystems, 2. https://doi.org/10.1128/mSystems.00124-16
Boiteau, R. M., Till, C. P., Ruacho, A., Bundy, R. M., Hawco, N. J., McKenna, A. M., Barbeau, K. A., Bruland, K. W., Saito, M. A., & Repeta, D. J. (2016). Structural characterization of natural nickel and copper binding ligands along the US GEOTRACES Eastern Pacific Zonal Transect. Frontiers in Marine Science, 3(243). https://doi.org/10.3389/fmars.2016.00243
Hogle, S. L., Bundy, R. M., Blanton, J. M., Allen, E. E., & Barbeau, K. A. (2016). Copiotrophic marine bacteria are associated with strong iron-binding ligand production during phytoplankton blooms. Limnology and Oceanography Letters. https://doi.org/10.1002/lol2.10026
Semeniuk, D. M., Bundy, R. M., Posacka, A. M., Robert, M., Barbeau, K. A., & Maldonado, M. T. (2016). Using 67Cu to study the biogeochemical cycling of copper in the northeast subarctic Pacific Ocean. Frontiers in Marine Science, 3(78). https://doi.org/10.3389/fmars.2016.00078
Hogle, S. L., Thrash, J. C., Dupont, C. L., & Barbeau, K. A. (2016). Trace metal acquisition by marine heterotrophic bacterioplankton with contrasting trophic strategies. Applied and Environmental Microbiology, 82(5), 1613–1624. https://doi.org/10.1128/aem.03128-15
Bundy, R. M., Jiang, M., Carter, M., & Barbeau, K. A. (2016). Iron-binding ligands in the southern California Current System: Mechanistic studies. Frontiers in Marine Science, 3(27). https://doi.org/10.3389/fmars.2016.00027
Semeniuk, D. M., Taylor, R. L., Bundy, R. M., Johnson, W. K., Cullen, J. T., Robert, M., Barbeau, K. A., & Maldonado, M. T. (2016). Iron-copper interactions in iron-limited phytoplankton in the northeast subarctic Pacific Ocean. Limnology and Oceanography, 61(1), 279–297. https://doi.org/10.1002/lno.10210
Brzezinski, M. A., Krause, J. W., Bundy, R. M., Barbeau, K. A., Franks, P., Goericke, R., Landry, M. R., & Stukel, M. R. (2015). Enhanced silica ballasting from iron stress sustains carbon export in a frontal zone within the California Current. Journal of Geophysical Research-Oceans, 120(7), 4654–4669. https://doi.org/10.1002/2015jc010829
Bundy, R. M., Abdulla, H. A. N., Hatcher, P. G., Biller, D. V., Buck, K. N., & Barbeau, K. A. (2015). Iron-binding ligands and humic substances in the San Francisco Bay estuary and estuarine-influenced shelf regions of coastal California. Marine Chemistry, 173, 183–194. https://doi.org/10.1016/j.marchem.2014.11.005
Pizeta, I., Sander, S. G., Hudson, R. J. M., Omanovic, D., Baars, O., Barbeau, K. A., Buck, K. N., Bundy, R. M., Carrasco, G., Croot, P. L., Garnier, C., Gerringa, L. J. A., Gledhill, M., Hirose, K., Kondo, Y., Laglera, L. M., Nuester, J., Rijkenberg, M. J. A., Takeda, S., … Wells, M. (2015). Interpretation of complexometric titration data: An intercomparison of methods for estimating models of trace metal complexation by natural organic ligands. Marine Chemistry, 173, 3–24. https://doi.org/10.1016/j.marchem.2015.03.006
Fitzsimmons, J. N., Bundy, R. M., Al-Subiai, S. N., Barbeau, K. A., & Boyle, E. A. (2015). The composition of dissolved iron in the dusty surface ocean: An exploration using size-fractionated iron-binding ligands. Marine Chemistry, 173, 125–135. https://doi.org/10.1016/j.marchem.2014.09.002
Semeniuk, D. M., Bundy, R. M., Payne, C. D., Barbeau, K. A., & Maldonado, M. T. (2015). Acquisition of organically complexed copper by marine phytoplankton and bacteria in the northeast subarctic Pacific Ocean. Marine Chemistry, 173, 222–233. https://doi.org/10.1016/j.marchem.2015.01.005
Dupont, C. L., McCrow, J. P., Valas, R., Moustafa, A., Walworth, N., Goodenough, U., Roth, R., Hogle, S. L., Bai, J., Johnson, Z. I., Mann, E., Palenik, B., Barbeau, K. A., Craig Venter, J., & Allen, A. E. (2014). Genomes and gene expression across light and productivity gradients in eastern subtropical Pacific microbial communities. Isme Journal, 9(5), 1076–1092. https://doi.org/10.1038/ismej.2014.198
Roe, K. L., & Barbeau, K. A. (2014). Uptake mechanisms for inorganic iron and ferric citrate in Trichodesmium erythraeum IMS101. Metallomics, 6(11), 2042–2051. https://doi.org/10.1039/c4mt00026a
Bundy, R. M., Biller, D. V., Buck, K. N., Bruland, K. W., & Barbeau, K. A. (2014). Distinct pools of dissolved iron-binding ligands in the surface and benthic boundary layer of the California Current. Limnology and Oceanography, 59(3), 769–787. https://doi.org/10.4319/lo.2014.59.3.0769
Hogle, S. L., Barbeau, K. A., & Gledhill, M. (2014). Heme in the marine environment: from cells to the iron cycle. Metallomics, 6(6), 1107–1120. https://doi.org/10.1039/c4mt00031e
Earley, P. J., Swope, B. L., Barbeau, K., Bundy, R., McDonald, J. A., & Rivera-Duarte, I. (2014). Life cycle contributions of copper from vessel painting and maintenance activities. Biofouling, 30(1), 51–68. https://doi.org/10.1080/08927014.2013.841891
Ohman, M. D., Barbeau, K., Franks, P. J. S., Goericke, R., Landry, M. R., & Miller, A. J. (2013). Ecological transitions in a coastal upwelling ecosystem. Oceanography, 26(3), 210–219.
Roe, K. L., Hogle, S. L., & Barbeau, K. A. (2013). Utilization of heme as an iron source by marine alphaproteobacteria in the roseobacter clade. Applied and Environmental Microbiology, 79(18), 5753–5762. https://doi.org/10.1128/aem.01562-13
Hopkinson, B. M., Seegers, B., Hatta, M., Measures, C. I., Mitchell, B. G., & Barbeau, K. A. (2013). Planktonic C:Fe ratios and carrying capacity in the southern Drake Passage. Deep-Sea Research Part Ii-Topical Studies in Oceanography, 90, 102–111. https://doi.org/10.1016/j.dsr2.2012.09.001
Jiang, M. S., Barbeau, K. A., Selph, K. E., Measures, C. I., Buck, K. N., Azam, F., Mitchell, B. G., & Zhou, M. (2013). The role of organic ligands in iron cycling and primary productivity in the Antarctic Peninsula: A modeling study. Deep-Sea Research Part Ii-Topical Studies in Oceanography, 90, 112–133. https://doi.org/10.1016/j.dsr2.2013.01.029
Bundy, R. M., Barbeau, K. A., & Buck, K. N. (2013). Sources of strong copper-binding ligands in Antarctic Peninsula surface waters. Deep-Sea Research Part Ii-Topical Studies in Oceanography, 90, 134–146. https://doi.org/10.1016/j.dsr2.2012.07.023
Landry, M. R., Ohman, M. D., Goericke, R., Stukel, M. R., Barbeau, K. A., Bundy, R., & Kahru, M. (2012). Pelagic community responses to a deep-water front in the California Current Ecosystem: overview of the A-Front Study. Journal of Plankton Research, 34(9), 739–748. https://doi.org/10.1093/plankt/fbs025
Buck, K. N., Moffett, J., Barbeau, K. A., Bundy, R. M., Kondo, Y., & Wu, J. F. (2012). The organic complexation of iron and copper: an intercomparison of competitive ligand exchange-adsorptive cathodic stripping voltammetry (CLE-ACSV) techniques. Limnology and Oceanography-Methods, 10, 496–515. https://doi.org/10.4319/lom.2012.10.496
Roe, K. L., Barbeau, K., Mann, E. L., & Haygood, M. G. (2012). Acquisition of iron by Trichodesmium and associated bacteria in culture. Environmental Microbiology, 14(7), 1681–1695. https://doi.org/10.1111/j.1462-2920.2011.02653.x
King, A. L., Buck, K. N., & Barbeau, K. A. (2012). Quasi-Lagrangian drifter studies of iron speciation and cycling off Point Conception, California. Marine Chemistry, 128, 1–12. https://doi.org/10.1016/j.marchem.2011.11.001
Hopkinson, B. M., & Barbeau, K. A. (2012). Iron transporters in marine prokaryotic genomes and metagenomes. Environmental Microbiology, 14(1), 114–128. https://doi.org/10.1111/j.1462-2920.2011.02539.x
King, A. L., & Barbeau, K. A. (2011). Dissolved iron and macronutrient distributions in the southern California Current System. Journal of Geophysical Research-Oceans, 116. https://doi.org/10.1029/2010jc006324
Buck, K. N., Selph, K. E., & Barbeau, K. A. (2010). Iron-binding ligand production and copper speciation in an incubation experiment of Antarctic Peninsula shelf waters from the Bransfield Strait, Southern Ocean. Marine Chemistry, 122(1–4), 148–159. https://doi.org/10.1016/j.marchem.2010.06.002
Dupont, C. L., Buck, K. N., Palenik, B., & Barbeau, K. (2010). Nickel utilization in phytoplankton assemblages from contrasting oceanic regimes. Deep-Sea Research Part I-Oceanographic Research Papers, 57(4), 553–566. https://doi.org/10.1016/j.dsr.2009.12.014