The organic complexation of iron in the marine environment: A review

Frontiers in Microbiology

Volumn 3, Issue FEB, 2012, Pages

  Gledhiir, Martha ^a   Buck, Kristen N ^b  

^a UNIVERSITY OF SOUTHAMPTON   (United Kingdom)

^b BERMUDA INSTITUTE OF OCEAN SCIENCES   (Bermuda)

Author keywords

Colloids; Exopolymeric substances; Humic substances; Ligands; Nanoparticles; Seawater; Siderophores; Speciation

Indexed keywords

EID: 84872348968     PISSN: None     EISSN: 1664302X     Source Type: Journal    
DOI: 10.3389/fmicb.2012.00069     Document Type: Article

References (149)

1. Amin, S. A., Green, D. H., Hart, M. C., Kupper, E C., Sunda, W. G., and Carrano, C. J. (2009). Photolysis of iron-siderophore chelates promotes bacterial-algal mutualism. Proc. Natl. Acad. Sci. U.S.A. 106, 17071-17076.
2. Archer, D. E., and Johnson, K. (2000). A model of the iron cycle in the ocean. Global Biogeochem. Cycles 14, 269-279.
3. Baalousha, M., Stolpe, B., and Lead, J. R. (2011). Flow field-flow fractionation for the analysis and characterization of natural colloids and manufactured nanoparticles in environmental systems: a critical review. J. Chromatogr. A 1218, 4078-4103.
4. Barbeau, K., Rue, E. L., Trick, C. G., Bruland, K. T., and Butler, A. (2003). Photochemical reactivity of siderophores produced by marine heterotrophic bacteria and cyanobacteria based on characteristic Fe(III) binding groups. Limnol. Oceanogr. 48, 1069-1078.
5. Barbeau, K. A., Rue, E. L., Bruland, K., W" and Butler, A. (2001). Photochemical cycling of iron in the surface ocean mediated by microbial iron(III)-binding ligands. Nature 413,409-413.
6. Batchelli, S., Muller, E L. L., Baalousha, M., and Lead, J. R. (2009). Size fractionation and optical properties of colloids in an organic-rich estuary (Thurso, UK). Mar. Chem. 113, 227-237.
7. Batchelli, S., Muller, E L. L., Chang, K. C., and Lee, C. L. (2010). Evidence for strong but dynamic iron-humic colloidal associations in humic-rich coastal waters. Environ. Sci. Technol. 44,8485-8490.
8. Bennett, S. A., Achterberg, E. P., Connelly, D. P., Statharn, P. J., Fones, G. R., and Gernian, C. R. (2008). The distribution and stabilisation of dissolved Fe in deep-sea hydrothermal plumes. Earth Planet. Sci. Lett. 270, 157-167.
9. Bergquist, B. A., Wu, J., and Boyle, E. A. (2007). Variability in oceanic dissolved iron is dominated by the colloidal fraction. Geochim. Cosmochim. Acta 71, 2960-2974.
10. Bligh, M. W., and Waite, T. D. (2010). Role of heterogeneous precipitation in determining the nature of products formed on oxidation of Fe(II) in seawater containing natural organic matter. Environ. Sci. Technol. 44, 6667-6673.
11. Boyd, P. W., and Ellwood, M. J. (2010). The biogeochemical cycle of iron in the ocean. Nat. Geosci. 3, 675-682.
12. Boyd, P. W., Ibisanmi, E., Sander, S. G., Hunter, K. A., and Jackson, G. A. (2010). Remineralization of upper ocean particles: implications for iron biogeochemistry. Limnol. Oceanogr. 55, 1271-1288.
13. Boyd, P. W., Jickells, T., Law, C. S., Blain, S., Boyle, E. A., Buesseler, K. O., Coale, K. H., Cullen, J. J., De Baar, H. J. W., Follows, M., Harvey, M., Lancelot, C., Levasseur, M., Owens, N. P. J., Pollard, R., Rivkin, R. B., Sarmiento, J., Schoe-mann, V., Smetacek, V., Takeda, S., Tsuda, A., Turner, S., and Watson, A. J. (2007). Mesoscale iron enrichment experiments 1993-2005: synthesis and future directions. Science 315,612-617.
14. Boye, M., Aldrich, A., Van Den Berg, C. M. G., De Jong, J. T. M., Nirmaier, H., Veldhuis, M., Timmermans, K. R., and De Baar, H. J. W. (2006). The chemical speciation of iron in the north-east Atlantic Ocean. Deep Sea Res. PartI Oceanogr. Res. Pap. 53, 667-683.
15. Boye, M., Nishioka, J., Croot, P., Laan, P., Timmermans, K. R., Strass, V. H., Takeda, S., and De Baar, H. J. W. (2010). Significant portion of dissolved organic Fe complexes in fact is Fe colloids. Mar. Chem. 122, 20-27.
16. Boye, M., Nishioka, J., Croot, P. L., Laan, P., Timmermans, K. R., and De Baar, H. J. W. (2005). Major deviations of iron complexation during 22 days of a mesoscale iron enrichment in the open Southern Ocean. Mar. Chem. 96,257-271.
17. Boye, M., Van Den Berg, C. M. G., De Jong, J. T. M., Leach, H., Croot, P., and De Baar, H. J. W. (2001). Organic complexation of iron in the Southern Ocean. Deep Sea Res. PartI Oceanogr. Res. Pap. 48, 1477-1497.
18. Boye, M. B., Aldrich, A. P., Van Den Berg, C. M. G., De Jong, J. T. M., Veldhuis, M.J.W.,andDeBaar,H.J.W. (2003). Horizontal gradient of the chemical speciation of iron in surface waters of N.E. Atlantic Ocean. Mar. Chem. 80, 129-143.
19. Bruland, K. W., Rue, E. L., Donat, J. R., Skrabal, S. A., and Moffett, J. W. (2000). Intercomparison of voltammetric techniques to determine the chemical speciation of dissolved copper in a coastal seawater sample. Anal. Chim. Acta 405, 99-113.
20. Bruland, K. W., and Rue, E. L. (2001). "Analytical methods for the determination of concentrations and speciation of iron," in The Biogeochemistry of Iron in Seawater, eds D. R. Turner and K. A. Hunter (Chich-ester: Wiley), 255-290.
21. Buck, K. N., and Bruland, K. W. (2007). The physicochemical speciation of dissolved iron in the Bering Sea, Alaska. Limnol. Oceanogr. 52, 1800-1808.
22. Buck, K. N., Lohan, M. C., Berger, C. J. M., and Bruland, K. W. (2007). Dissolved iron speciation in two distinct river plumes and an estuary: implications for riverine iron supply. Limnol. Oceanogr. 52, 843-855.
23. Buck, K. N., Selph, K. E., and 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. Mar. Chem. 122, 148-159.
24. Byrne, R. H., Kump, L. R., and Cantrell, K. J. (1988). The influence of temperature and pH on trace metal speciation in seawater. Mar. Chem. 25, 163-181.
25. Cabaj, A., and Kosakowska, A. (2009). Iron-dependent growth of and siderophore production by two heterotrophic bacteria isolated from brackish water of the southern Baltic Sea. Microbiol. Res. 164, 570-577.
26. Chen, M., and Wang, W X. (2008). Accelerated uptake by phytoplankton of iron bound to humic acids. Aquat. Biol. 3, 155-166.
27. Croot, P. L., Andersson, K., Öztürk, M., and Turner, D. R. (2004). The distribution and speciation of iron along 6°E in the Southern Ocean. Deep Sea Res. Part II Top. Stud. Oceanogr. 51, 2857-2879.
28. Croot, P. L., and Johansson, M. (2000). Determination of iron speciation by cathodic stripping voltammetry in seawater using the competing ligand 2-(2-thiazolylazo)-p-cresol (TAC). Electroanalysis 12, 565-576.
29. Croot, P. L., Laan, P., Nishioka, J., Strass, V., Cisewski, B., Boye, M., Timmermans, K. R., Bellerby, R. G., Goldson, L., Nightingale, P., and De Baar, H. J. W. (2005). Spatial and temporal distribution of Fe(II) and H2O2 during EisenEx, an open ocean mescoscale iron enrichment. Mar. Chem. 95, 65-88.
30. Cullen, J. T., Bergquist, B. A., and Mof-fett, J. W. (2006). Thermodynamic characterization of the partitioning of iron between soluble and colloidal species in the Atlantic Ocean. Mar. Chem. 98, 295-303.
31. Cutter, G., Andersson, P., Codis-poti, L., Croot, P., Francois, R., Lohan, M., Obata, H., and Rutgers Van Der Loeff, M. (eds). (2010). Sampling and Sample-Handling Protocols for GEOTRACES Cruises. GEOTRACES. Available at: http://www.geotraces.org/library/ geotraces-policies/170-sampling-and-sample-handling-protocols-for-geotraces-cruises
32. De Baar, H. J. W., and De Jong, J. T. M. (2001). "Distribution, sources and sinks of iron in seawater," in The Biogeochemistry of Iron in Seawater, eds D. R. Turner and K. A. Hunter (Chichester: Wiley), 123-253.
33. Elrod, V. A., Berelson, W. M., Coale, K. H., and Johnson, K. S. (2004). The flux of iron from continental shelf sediments: a missing source for global budgets. Geophys. Res. Lett. 31,L12307.
34. Fan, S. M. (2008). Photochemical and biochemical controls on reactive oxygen and iron speciation in the pelagic surface ocean. Mar. Chem. 109, 152-164.
35. Fan, S. M., and Dunne, J. P. (2011). Models of iron speciation and concentration in the stratified epipelagic ocean. Geophys. Res. Lett. 38, L15611.
36. Garnier, C., Pizeta, I., Mounier, S., Benaim, J. Y., and Branica, M. (2004). Influence of the type of titration and of data treatment methods on metal complexing parameters determination of single and multi-ligand systems measured by stripping voltammetry. Anal. Chim. Acta 505, 263-275.
37. Gerringa, L. J. A., Herman, P. M. J., and Poortvliet, T. C. W. (1995). Comparison of the linear Van den Berg/RuziC transformation and the non-linear fit of the Langmuir isotherm applied to Cu speciation data in the estuarine environ ment. Mar. Chem. 48,131-142.
38. Gerringa, L. J. A., Blain, S., Laan, P., Sarthou, G., Veldhuis, M. J. W., Brussaard, C. P. D., Viollier, E., and Timmermans, K. R. (2008). Fe-binding dissolved organic ligands near the Kerguelen Archipelago in the Southern Ocean (Indian Sector). Deep Sea Res. Part I Oceanogr. Res. Pap. 55, 606-621.
39. Gerringa, L. J. A., Rijkenberg, M. J. A., Wolterbeek, H. T., Verburg, T. G., Boye, M., and De Baar, H. J. W. (2007). Kinetic study reveals weak Fe-binding ligand, which affects the solubility of Fe in the Scheldt estuary. Mar. Chem. 103, 30-45.
40. Gerringa, L. J. A., Veldhuis, M. J. W., Timmermans, K. R., Sarthou, G., and De Baar, H. J. W. (2006). Co-variance of dissolved Fe-binding ligands with phytoplankton characteristics in the Canary Basin. Mar. Chem. 102,276-290.
41. Gledhill, M., Mccormack, P., Ussher, S., Achterberg, E. P., Mantoura, R. F. C., and Worsfold, P. J. (2004). Production of siderophore type chelates by mixed bacterioplankton populations in nutrient enriched seawater incubations. Mar. Chem. 88, 75-83.
42. Gledhill, M., and van den Berg, C. M. G. (1994). Determination of complexation of iron (III) with natural organic complexing ligands in sea water using cathodic stripping voltammetry. Mar. Chem. 47, 41-54.
43. Gledhill, M., and van den Berg, C. M. G. (1995). Measurement of the redox speciation of iron in seawater by catalytic cathodic stripping voltammetry. Mar. Chem. 50,51-61.
44. Gledhill, M., Van Den Berg, C. M. G., Nolting, R. F., and Timmermans, K. R. (1998). Variability in the speciation of iron in the northern North Sea. Mar. Chem. 59,283-300.
45. Gobler, C. J., Donat, J. R., Consolvo, J. A. III, and Sanudo-Whilhelmy, S. A. (2002). Physicochemical speciation of iron during coastal algal blooms. Mar. Chem. 77,71-89.
46. Gyurcsik, B., and Nagy, L. (2000). Carbohydrates as ligands: coordination equilibria and structure of the metal complexes. Coord. Chem. Rev. 203, 81-149.
47. Hansard, S. P., Landing, W. M., Measures, C. I., and Voelkar, B. M. (2009). Dissolved iron(II) in the Pacific Ocean: measurements from PO2 and P16N Clivar/CO2 repeat hydrography expeditions. Deep Sea Res. Part I Oceanogr. Res. Pap. 56, 1117-1129.
48. Harris, W. R., Carrano, C. J., and Raymond, K. N. (1979a). Coordination chemistry of microbial iron transport compounds.16. Isolation, characterization, and formation-constants of ferric aerobactin. J. Am. Chem. Soc. 101, 2722-2727.
49. Harris, W. R., Carrano, C. J., and Raymond, K. N. (1979b). Spectrophoto-metric determination of the proton-dependent stability constant of ferric enterobactin. J. Am. Chem. Soc. 101, 2213-2214.
50. Hassler, C. S., Alasonati, E., Nichols, C. A. M., and Slaveykova, V I. (2011a). Exopolysaccharides produced by bacteria isolated from the pelagic Southern Ocean - role in Fe binding, chemical reactivity, and bioavailability. Mar. Chem. 123, 88-98.
51. Hassler, C. S., Schoemann, V., Nichols, C. M., Butler, E. C. V., and Boyd, P. W. (2011b). Saccharides enhance iron bioavailability to Southern Ocean phytoplankton. Proc. Natl. Acad. Sci. U.S.A. 108, 1076-1081.
52. Hider, R. C., and Kong, X. L. (2010). Chemistry and biology of siderophores. Nat. Prod. Rep. 27, 637-657.
53. Hirose, K. (2006). Chemical speciation of trace metals in seawater: a review. Anal. Sci. 22,1055-1063.
54. Hirose, K. (2007). Metal-organic matter interaction: ecological roles of ligands in oceanic DOM. Appl. Geochem. 22,1636-1645.
55. Homann, V V, Edwards, K. J., Webb, E. A., and Butler, A. (2009a). Siderophores of Marinobacter aquaeolei: petrobactin and its sulfonated derivatives. Biometals 22, 565-571.
56. Homann, V V, Sandy, M., Tincu, J. A., Templeton, A. S., Tebo, B. M., and Butler, A. (2009b). Loihichelins A-F, a suite of amphiphilic siderophores produced by the marine bacterium Halomonas LOB-5. J. Nat. Prod. 72, 884-888.
57. Hong, H., and Kester, D. R. (1986). Redox state of iron in the offshore waters of Peru. Limnol. Oceanogr. 31, 512-524.
58. Hopkinson, B. M., and Barbeau, K. A. (2007). Organic and redox speciation of iron in the eastern tropical North Pacific suboxic zone. Mar. Chem. 106,2-17.
59. Hudson, R. J. M., Covault, D. T., and Morel, F. M. M. (1992). Investigations of iron coordination and redox reactions in seawater using 59Fe radiometry and ion-pair solvent extraction of amphiphilic iron complexes. Mar. Chem. 38, 209-235.
60. Hunter, K. A., and Boyd, P. W. (2007). Iron-binding ligands and their role in the ocean biogeochemistry of iron. Environ. Chem. 4, 221-232.
61. Hurst, M. P., and Bruland, K. W (2008). The effects of the San Francisco Bay plume on trace metal and nutrient distributions in the Gulf of the Far-allones. Geochim. Cosmochim. Acta 72,395-411.
62. Hutchins, D. A., Witter, A. E., Butler, A., and Luther, G. W III. (1999). Competition among marine phytoplankton for different chelated iron species. Nature 400, 858-861.
63. Ibisanmi, E., Sander, S. G., Boyd, P. W., Bowie, A. R., and Hunter, K. A. (2011). Vertical distributions of iron-(III) complexing ligands in the Southern Ocean. Deep Sea Res. Part II Top. Stud. Oceanogr. 58, 2113-2125.
64. Ito, Y., and Butler, A. (2005). Structure of synechobactins, new siderophores of the marine cyanobacterium Synechococcus sp PCC 7002. Limnol. Oceanogr. 50, 1918-1923.
65. Johnson, K. S., Coale, K. H., Elrod, V. A., and Tindale, N. W. (1994). Iron photochemistry in waters from the equatorial Pacific. Mar. Chem. 46, 319-334.
66. King, A. L., Buck, K. N., and Barbeau, K. A. (2012). Quasi-Lagrangian drifter studies of iron speciation and cycling off Point Conception, California. Mar. Chem. 128-129,1-12.
67. Kitayama, S., Kuma, K., Manabe, E., Sugie, K., Takata, H., Isoda, Y., Toya, K., Saitoh, S. I., Takagi, S., Kamei, Y., and Sakaoka, K. (2009). Controls on iron distributions in the deep water column of the North Pacific Ocean: iron(III) hydroxide solubility and marine humic-type dissolved organic matter.J. Geophys. Res. 114, C08019.
68. Kondo, Y., Takeda, S., and Furuya, K. (2007). Distribution and speciation of dissolved iron in the Sulu Sea and its adjacent waters. Deep Sea Res. Part II Top. Stud. Oceanogr. 54, 60-80.
69. Kondo, Y., Takeda, S., Nishioka, J., Obata, H., Furuya, K., Johnson, W. K., and Wong, C. S. (2008). Organic iron(III) complexing ligands during an iron enrichment experiment in the western subarctic North Pacific. Geophys. Res. Lett. 35,L12601.
70. Kosakowska, A., Kupryszewski, G., Mucha, P., Rekowski, P., Lewandowska, J., and Pazdro, K. (1999). Identification of selected siderophores in the Baltic Sea environment by the use of capillary electrophoresis. Oceanologia 41, 573-587.
71. Kuma, K., and Matsunaga, K. (1995). Availability of colloidal ferric oxides to coastal marine-phytoplankton. Mar.Biol. 122, 1-11.
72. Kuma, K., Nakabayashi, S., Suzuki, Y., Kudo, I., and Matsunaga, K. (1992). Photo-reduction of Fe(III) by dissolved organic substances and existence of Fe(II) in seawater during spring blooms. Mar. Chem. 37, 15-27.
73. Kuma, K., Nishioka, J., and Matsunaga, K. (1996). Controls on iron(III) hydroxide solubility in seawater: the influence of pH and natural organic chelators. Limnol Oceanogr. 41,396-407.
74. Laglera, L. M., Battaglia, G., and Van Den Berg, C. M. G. (2007). Determination of humic substances in natural waters by cathodic stripping voltammetry of their complexes with iron. Anal. Chim. Acta 599, 58-66.
75. Laglera, L. M., Battaglia, G., and Van Den Berg, C. M. G. (2011). Effect of humic substances on the iron speciation in natural waters by CLE/CSV. Mar. Chem. 127, 134-143.
76. Laglera, L. M., and van den Berg, C. M. G. (2009). Evidence for geochemical control of iron by humic substances in seawater. Limnol. Oceanogr. 54, 610-619.
77. Lam, P. J., and Bishop, J. K. B. (2008). The continental margin is a key source of iron to the HNLC North Pacific Ocean. Geophys. Res. Lett. 35, L07608.
78. Liu, X., and Millero, E J. (2002). The solubility of iron in seawater. Mar. Chem. 77, 43-54.
79. Loomis, L. D., and Raymond, K. N. (1991). Solution equilibria of enterobactin and metal enter-obactin complexes. Inorg. Chem. 30, 906-911.
80. Macrellis, H. M., Trick, C. G., Rue, E. L., Smith, G., and Bruland, K. (2001). Collection and detection of natural iron-binding ligands from seawater. Mar. Chem. 76, 175-187.
81. Maldonado, M. T., and Price, N. M. (2001). Reduction and transport of organically bound iron by Thalas-siosira oceanica (Bacillariophyceae). J. Phycol. 37,298-309.
82. Maldonado, M. T., Strzepek, R. F., Sander, S., and Boyd, P. W. (2005). Acquisition of iron bound to strong organic complexes, with different Fe binding groups and photochemical reactivities, by plankton communities in Fe-limited subantarctic waters. GlobalBiogeochem. Cycles 19, GB4S23.
83. Mancuso Nichols, C. A., Garon, S., Bowman, J. P., Raguenes, G., and Guezennec, J. (2004). Production of exopolysaccharides by Antarctic marine bacterial isolates. J. Appl. Microbiol. 96, 1057-1066.
84. Martin, J. D., Ito,Y., Homann.V V, Haygood, M. G., and Butler, A. (2006). Structure and membrane affinity of new amphiphilic siderophores produced by Ochrobactrum sp SP18. J. Biol. Inorg. Chem. 11, 633-641.
85. Martin, J. H., and Fitzwater, S. (1988). Iron deficiency limits phytoplankton growth in the north-east Pacific subarctic. Nature 331, 341-343.
86. Martinez, J. S., and Butler, A. (2007). Marine amphiphilic siderophores: marinobactin structure, uptake, and microbial partitioning. J. Inorg. Biochem. 101,1692-1698.
87. Martinez, J. S., Carter-Franklin, J. N., Mann, E. L., Martin, J. D., Haygood, M. G., and Butler, A. (2003). Structure and membrane affinity of a suite of amphiphilic siderophores produced by a marine bacterium. Proc. Natl. Acad. Sci. U.S.A. 100, 3754-3759.
88. Martinez, J. S., Zhang, G. P., Holt, P. D., Jung, H.-T., Carrano, C. J., Haygood, M. G., and Butler, A. (2000). Self-assembling amphiphilic siderophores from marine bacteria. Science 287, 1245-1247.
89. Mawji, E., Gledhill, M., Milton, J. A., Tarran, G. A., Ussher, S., Thompson, A., Wolff, G. A., Worsfold, P. J., and Achterberg, E. P. (2008a). Hydroxa-mate siderophores: occurrence and importance in the Atlantic Ocean. Environ. Sci. Technol. 42, 8675-8680.
90. Mawji, E., Gledhill, M., Worsfold, P. J., and Achterberg, E. P. (2008b). Collision-induced dissociation of three groups of hydroxamate siderophores: ferrioxamines, fer-richromes and coprogens/fusigens. Rapid Commun. Mass Spectrom. 22, 2195-2202.
91. Mawji, E., Gledhill, M., Milton, J. A., Zubkov, M. V., Thompson, A., Wolff, G. A., and Achterberg, E. P. (2011). Production of siderophore type chelates in Atlantic Ocean waters enriched with different carbon and nitrogen sources. Mar. Chem. 124, 90-99.
92. McCormack, P., Worsfold, P. J., and Gledhill, M. (2003). Separation and detection of siderophores produced by marine bacterioplankton using high-performance liquid chromatography with electrospray ionization mass spectrometry. Anal. Chem. 75, 2647-2652.
93. Mochizuki, N., Tanaka, R., Grimm, B., Masuda, T., Moulin, M., Smith, A. G., Tanaka, A., and Terry, M. J. (2010). The cell biology of tetrapyrroles: a life and death struggle. Trends Plant Sci. 15,488-498.
94. Mohamed, K. N., Steigenberger, S., Nielsdottir, M. C., Gledhill, M., and Achterberg, E. P. (2011). Dissolved iron(III) speciation in the high latitude North Atlantic Ocean. Deep Sea Res. Part I Oceanogr. Res. Pap. 58, 1049-1059.
95. Moore, J. K., and Braucher, O. (2008). Sedimentary and mineral dust sources of dissolved iron to the world ocean. Biogeosciences 5, 631-656.
96. Moore, J. K., Doney, S. C., and Lindsay, K. (2004). Upper ocean ecosystem dynamics and iron cycling in a global three-dimensional model. Global Biogeochem. Cycles 18, GB4028.
97. Mucha, P., Rekowski, P., Kosakowska, A., and Kupryszewski, G. (1999). Separation of siderophores by capillary electrophoresis. J. Chromatogr. A 830,183-189.
98. Nishioka, J., Takeda, S., Wong, C. S., and Johnson, W K. (2001). Size-fractionated iron concentrations in the northeast Pacific Ocean: distribution of soluble and small colloidal iron. Mar. Chem. 74, 157-179.
99. Nolting, R. F., Gerringa, L. J. A., Swa-german, M. J. W., Timmermans, K. R., and De Baar, H. J. W. (1998). Fe (III) speciation in the high nutrient, low chlorophyll Pacific region of the Southern Ocean. Mar. Chem. 62, 335-352.
100. Owen, T., Pynn, R., Martinez, J. S., and Butler, A. (2005). Micelle-to-vesicle transition of an iron-chelating microbial surfactant, marinobactin E.Langmuir 21, 12109-12114.
101. Parekh, P., Follows, M. J., and Boyle, E. A. (2005). Decoupling of iron and phosphate in the global ocean. Global Biogeochem. Cycles 19, GB2020.
102. Poorvin, L., Sander, S. G., Velasquez, I., Ibisanmi, E., Lecleir, G. R., and Wilhelm, S. W. (2011). A comparison of Fe bioavailability and binding of a catecholate siderophore with virus-mediated lysates from the marine bacterium Vibrio alginolyticus PWH3a. J. Exp. Mar. Biol. Ecol. 399, 43-47.
103. Powell, R. T., and Wilson-Finelli, A. (2003a). Importance of organic Fe complexing ligands in the Mississippi River plume. Estuar Coast Shelf Sci 58, 757-763.
104. Powell, R. T., and Wilson-Finelli, A. (2003b). Photochemical degradation of organic iron complexing ligands in seawater. Aquat Sci 65, 367-374.
105. 2-evolving organisms. Photosyn. Res. 60,111-149.
106. Rijkenberg, M. J. A., Gerringa, L. J. A., Carolus, V E., Velzeboer, I., and De Baar, H. J. W. (2006a). Enhancement and inhibition of iron photoreduction by individual ligands in open ocean seawater. Geochim. Cosmochim. Acta 70,2790-2805.
107. Rijkenberg, M. J. A., Gerringa, L. J. A., Velzeboer, I., Timmermans, K. R., Buma, A. G. J., and De Baar, H. J. W. (2006b). Iron-binding ligands in Dutch estuaries are not affected by UV induced photochemical degradation. Mar. Chem. 100, 11-23.
108. Rijkenberg, M. J. A., Gerringa, L. J. A., Timmermans, K. R., Fischer, A. C., Kroon, K. J., Buma, A. G. J., Wolterbeek, B. T., and De Baar, H. J. W. (2008a). Enhancement of the reactive iron pool by marine diatoms. Mar. Chem. 109, 29-44.
109. Rijkenberg, M. J. A., Powell, C. F., Dall'osto, M., Nielsdottir, M. C., Patey M. D., Hill, P. G., Baker, A. R., Jickells, T. D., Harrison, R. M., and Achterberg, E. P. (2008b). Changes in iron speciation following a Saharan dust event in the tropical North Atlantic Ocean. Mar. Chem. 110, 56-67.
110. Rue, E., and Bruland, K. (2001). Domoic acid binds iron and copper: a possible role for the toxin produced by the marine diatom Pseudo-nitzschia. Mar. Chem. 76, 127-134.
111. Rue, E. L., and Bruland, K. W (1995). Complexation of iron(III) by natural organic ligands as determined by a new competitive equilibration/adsorptive cathodic stripping voltammetry method. Mar. Chem. 50,117-139.
112. Rue, E. L., and Bruland, K. W (1997). The role of organic complexation on ambient iron chemistry in the Equatorial Pacific Ocean and the response of a mesoscale iron addition experiment. Limnol. Oceanogr. 42,901-910.
113. Ružic, I. (1982). Theoretical aspects of the direct titration of natural-waters and its information yield for trace-metal speciation. Anal. Chim. Acta 140,99-113.
114. Sander, S. G., Hunter, K. A., Harms, H., and Wells, M. (2011). Numerical approach to speciation and estimation of parameters used in modeling trace metal bioavailability. Environ. Sci. Technol. 45, 6388-6395.
115. Sander, S. G., and Koschinsky, A. (2011). Metal flux from hydrothermal vents increased by organic complexation. Nat. Geosci. 4, 145-150.
116. Sarthou, G., Bucciarelli, E., Chever, F., Hansard, S. P., Gonzalez-Davila, M., Santana-Casiano, J. M., Planchon, F., and Speich, S. (2011). Labile Fe(II) concentrations in the Atlantic sector of the Southern Ocean along a transect from the subtropical domain to the Weddell Sea Gyre. Biogeosciences 8,2461-2479.
117. Sato, M., Takeda, S., and Furuya, K. (2007). Iron regeneration and organic iron(III)-binding ligand production during in situ zooplankton grazing experiment. Mar. Chem. 106,471-488.
118. Scatchard, G. (1949). The attractions of proteins for small molecules and ions. Ann. N.Y. Acad. Sci. 51, 606-672.
119. Schlosser, C., and Croot, P. L. (2008). Application of cross-flow filtration for determining the solubility of iron species in open ocean seawater. Limnol. Oceanogr. 6, 630-642.
120. Silver, M. W., Bargu, S., Coale, S. L., Benitez-Nelson, C. R., Garcia, A. C., Roberts, K. J., Sekula-Wood, E., Bruland, K. W., and Coale, K. H. (2010). Toxic diatoms and domoic acid in natural and iron enriched waters of the oceanic Pacific. Proc. Natl. Acad. Sci. U.S.A. 107, 20762-20767.
121. Stintzi, A., Barnes, C., Xu, L., and Raymond, K. N. (2000). Microbial iron transport via a siderophore shuttle: a membrane ion transport paradigm. Proc. Natl Acad. Sci. U.S.A. 97,10691-10696.
122. Stolpe, B., Guo, L., Shiller, A. M., and Hassellov, M. (2010). Size and composition of colloidal organic matter and trace elements in the Mississippi River, Pearl River and the northern Gulf of Mexico, as characterized by flow field-flow fractionation. Mar. Chem. 118, 119-128.
123. Stolpe, B., and Hassellov, M. (2010). Nanofibrils and other colloidal biopolymers binding trace elements in coastal seawater: significance for variations in element size distributions. Limnol. Oceanogr. 55, 187-202.
124. Strmecki, S., Plavsic, M., Steigenberger, S., and Passow, U. (2010). Characterization of phytoplankton exu-dates and carbohydrates in relation to their complexation of copper, cadmium and iron. Mar. Ecol. 408, 33-46.
125. Sunda, W., and Huntsman, S. (2003). Effect of pH, light, and temperature on Fe-EDTA chelation and Fe hydrolysis in seawater. Mar. Chem. 84, 35-47.
126. Tagliabue, A., Bopp, L., Aumont, O., and Arrigo, K. R. (2009). Influence of light and temperature on the marine iron cycle: from theoretical to global modeling. Global Biogeochem. Cycles 23,2017.
127. Tagliabue, A., and Voelker, C. (2011). Towards accounting for dissolved iron speciation in global ocean models. Biogeosciences 8, 3025-3039.
128. Thuroczy, C. E., Gerringa, L. J. A., Klunder, M. B., Middag, R., Laan, P., Timmermans, K. R., and De Baar, H. J. W. (2010). Speciation of Fe in the Eastern North Atlantic Ocean. Deep Sea Res. PartI Oceanogr. Res. Pap. 57, 1444-1453.
129. Tian, F., Frew, R. D., Sander, S., Hunter, K. A., and Ellwood, M. J. (2006). Organic iron(III) speciation in surface transects across a frontal zone: the Chatham Rise, New Zealand. Mar. Freshw. Res. 57, 533-544.
130. Toner, B. M., Fakra, S. C., Man-ganini, S. J., Santelli, C. M., Marcus, M. A., Moffett, J., Rouxel, O., German, C. R., and Edwards, K. J. (2009). Preservation of iron(II) by carbon-rich matrices in a hydrothermal plume. Nat. Geosci. 2, 197-201.
131. Ussher, S. J., Worsfold, P. J., Achterberg, E. P., Laes, A., Blain, S., Laan, P., and De Baar, H. J. W. (2007). Distribution and redox speciation of dissolved iron on the European continental margin. Limnol. Oceanogr. 52, 2530-2539.
132. Van Den Berg, C. M. G. (1982). Determination of copper complexation with natural organic ligands in seawater by equilibration with MnO2. I. theory. Mar. Chem. 11, 307-322.
133. van den Berg, C. M. G. (1995). Evidence for organic complexation of iron in seawater. Mar. Chem. 50, 139-157.
134. van den Berg, C. M. G. (2006). Chemical speciation of iron in seawater by cathodic stripping voltammetry with dihydroxynaphthalene. Anal. Chem. 78, 156-163.
135. van der Merwe, P., Lannuzel, D., Nichols, C. A. M., Meiners, K., Heil, P., Norman, L., Thomas, D. N., and Bowie, A. R. (2009). Biogeochemical observations during the winter-spring transition in East Antarctic sea ice: evidence of iron and exopolysaccharide controls. Mar. Chem. 115, 163-175.
136. Velasquez, I., Nunn, B. L., Ibisanmi, E., Goodlet, D. R., Hunter, K. A., and Sander, S. G. (2011). Detection of hydroxamate siderophores in coastal and sub-Antarctic waters off the South Eastern coast of New Zealand. Mar. Chem. 126, 97-107.
137. Vong, L., Laes, A., and Blain, S. (2007). Determination of iron-porphyrin-like complexes at nanomolar levels in seawater. Anal. Chim. Acta 588, 237-244.
138. Vraspir, J., and Butler, A. (2009). Chemistry of marine ligands and siderophores. Ann. Rev. Mar. Sci. 1, 43-63.
139. Wagener, T., Pulido-Villena, E., and Guieu, C. (2008). Dust iron dissolution in seawater: results from a one-year time-series in the Mediterranean Sea. Geophys. Res. Lett. 35, L16601.
140. Weber, L., Volker, C., Schartau, M., and Wolf-Gladrow, D. A. (2005). Modeling the speciation and biogeochem-istry of iron at the Bermuda Atlantic Time-series Study site. Global Biogeochem. Cycles 19,GB1019.
141. Wells, M. L., Trick, C. G., Cochlan, W. P., Hughes, M. P., and Trainer, V. L. (2005). Domoic acid: the synergy of iron, copper, and the toxicity of diatoms. Limnol. Oceanogr. 50, 1908-1917.
142. Witter, A. E., Hutchins, D. A., Butler, A., and Luther, G. W. III. (2000). Determination of conditional stability constants and kinetic constants for strong model Fe-binding ligands in seawater. Mar. Chem. 69, 1-17.
143. Witter, A. E., and Luther, G. W. III. (1998). Variation in Fe-organic complexation with depth in the Northwestern Atlantic Ocean as determined using a kinetic approach. Mar. Chem. 62,241-258.
144. Wu,J., and Luther, G. W.III. (1994). Size fractionated iron concentrations in the water column of the Northwest Atlantic Ocean. Limnol. Oceanogr. 39, 1119-1129.
145. Wu, J., and Luther, G. W. III. (1995). Complexation of iron(III) by natural organic ligands in the Northwest Atlantic Ocean by a competitive ligand equilibration method and a kinetic approach. Mar. Chem. 50, 159-179.
146. Wu, J. F., Boyle, E., Sunda, W., and Wen, L. S. (2001). Soluble and colloidal iron in the oligotrophic North Atlantic and North Pacific. Science 293, 847-849.
147. Xu, G. F., Martinez, J. S., Groves, J. T., and Butler, A. (2002). Membrane affinity of the amphiphilic marinobactin siderophores. J. Am. Chem. Soc. 124, 13408-13415.
148. Ye, Y., Voelker, C., and Wolf-Gladrow, D. A. (2009). A model of Fe speciation and biogeochemistry at the Tropical Eastern North Atlantic Time-Series Observatory site. Biogeosciences 6, 2041-2061.
149. Yoshida, M., Kuma, K., Iwade, S., Isoda, Y., Takata, H., and Yamada, M. (2006). Effect of aging time on the availability of freshly precipitated ferric hydroxide to coastal marine diatoms. Mar. Biol. 149, 379-392.