title: Extracellular metal-binding activity of the sulphate-reducing bacterium Desulfococcus multivorans.
abstract: Polarography was used to measure the copper-binding ability of culture filtrates from a range of sulphate-reducing bacteria (SRB), including pure cultures and environmental isolates. Of those tested, Desulfococcus multivorans was shown to have the greatest copper-binding capacity and this organism was used for further experiments. Extracellular copper- and zinc-binding activities of Dc. multivorans culture filtrates from batch cultures increased over time and reached a maximum after 10 d growth. The culture filtrate was shown to bind copper reversibly and zinc irreversibly. Twelve-day-old Dc. multivorans culture filtrates were shown to have a copper-binding capacity of 3.64 +/- 0.33 micromol ml(-1) with a stability constant, log10K, of 5.68 +/- 0.64 (n=4). The metal-binding compound was partially purified from culture growth media by dichloromethane extraction followed by HPLC using an acetonitrile gradient.
authors.affiliation: Department of Biological Sciences, University of Dundee, UK.
authors.forename: T A
authors.initials: TA
authors.lastname: Bridge
authors.forename: C
authors.initials: C
authors.lastname: White
authors.forename: G M
authors.initials: GM
authors.lastname: Gadd
mesh_terms: D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D003300:Copper / Q000032:analysis / Q000378:metabolism; D020564:Deltaproteobacteria / Q000254:growth & development / Q000378:metabolism*; D007700:Kinetics; D008024:Ligands; D008670:Metals / Q000032:analysis / Q000378:metabolism*; D010084:Oxidation-Reduction; D011048:Polarography; D013431:Sulfates / Q000032:analysis / Q000378:metabolism*; D016999:Sulfur-Reducing Bacteria / Q000254:growth & development / Q000378:metabolism; D015032:Zinc / Q000032:analysis / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D008024:Ligands; D008670:Metals; D013431:Sulfates; D003300:Copper; D015032:Zinc