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Appl Environ Microbiol. 1989 May; 55(5): 1249–1257.
PMCID: PMC184285

Metal Interactions with Microbial Biofilms in Acidic and Neutral pH Environments

Abstract

Microbial biofilms were grown on strips of epoxy-impregnated filter paper submerged at four sites in water contaminated with metals from mine wastes. At two sample stations, the water was acidic (pH 3.1); the other sites were in a lake restored to a near neutral pH level by application of a crushed limestone slurry. During a 17-week study period, planktonic bacterial counts increased from 101 to 103 CFU/ml at all sites. Biofilm counts increased rapidly over the first 5 weeks and then leveled to 104 CFU/cm2 in the neutral pH system and 103 CFU/cm2 at the acidic sites. In each case, the biofilms bound Mn, Fe, Ni, and Cu in excess of the amounts adsorbed by control strips covered with nylon filters (pore size, 0.22 μm) to exclude microbial growth; Co bound under neutral conditions but not under acidic conditions. Conditional adsorption capacity constants, obtained graphically from the data, showed that biofilm metal uptake at a neutral pH level was enhanced by up to 12 orders of magnitude over acidic conditions. Similarly, adsorption strength values were usually higher at elevated pH levels. In thin sections of the biofilms, encapsulated bacterial cells were commonly found enmeshed together in microcolonies. The extracellular polymers often contained iron oxide precipitates which generated weak electron diffraction patterns with characteristic reflections for ferrihydrite (Fe2O3 · H2O) at d equaling 0.15 and 0.25 nm. At neutral pH levels, these deposits incorporated trace amounts of Si and exhibited a granular morphology, whereas acicular crystalloids containing S developed under acidic conditions.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Beveridge TJ, Meloche JD, Fyfe WS, Murray RG. Diagenesis of metals chemically complexed to bacteria: laboratory formation of metal phosphates, sulfides, and organic condensates in artificial sediments. Appl Environ Microbiol. 1983 Mar;45(3):1094–1108. [PMC free article] [PubMed]
  • Geesey GG, Richardson WT, Yeomans HG, Irvin RT, Costerton JW. Microscopic examination of natural sessile bacterial populations from an alpine stream. Can J Microbiol. 1977 Dec;23(12):1733–1736. [PubMed]
  • Ghiorse WC. Biology of iron- and manganese-depositing bacteria. Annu Rev Microbiol. 1984;38:515–550. [PubMed]
  • Ghiorse WC, Wilson JT. Microbial ecology of the terrestrial subsurface. Adv Appl Microbiol. 1988;33:107–172. [PubMed]
  • Huljev DJ. Interaction of some metals between marine-origin humic acids and aqueous solutions. Environ Res. 1986 Aug;40(2):470–478. [PubMed]
  • Weiner AA, Moore PA, Sheehan D. Current behavioral modes of reducing dental anxiety. Quintessence Int Dent Dig. 1982 Sep;13(9):981–985. [PubMed]
  • Mittelman MW, Geesey GG. Copper-binding characteristics of exopolymers from a freshwater-sediment bacterium. Appl Environ Microbiol. 1985 Apr;49(4):846–851. [PMC free article] [PubMed]
  • Palumbo AV, Bogle MA, Turner RR, Elwood JW, Mulholland PJ. Bacterial communities in acidic and circumneutral streams. Appl Environ Microbiol. 1987 Feb;53(2):337–344. [PMC free article] [PubMed]

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