Scholarly Work - Center for Biofilm Engineering
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Item Evaluation of occurrence and relative concentration of organic products of biofilm metabolism that accumulate at corroding copper surfaces(1989) Geesey, Gill G.; Jolley, John G.; Hankins, Michael R.Item Effects of environmental conditions on the sessile existence of an estuarine sediment bacterium(1984) Geesey, Gill G.; Salas, S. D.; Mittelman, M. W.A submerged glass coverslip technique was developed to determine dissolved organic nutrient uptake by adherent cells of a sediment isolate of Enterobacter cloacae . Cells which colonized the coverslips in swirling culture flasks during anaerobic growth remained firmly attached during manipulations employed to determine uptake of radiolabeled glucose by the adherent population. The attached cells were capable of a more rapid rate of glucose uptake than free cells. Lineweaver-Burk plots demonstrated different glucose uptake kinetics for the 2 cell populations. The data suggest that physiological changes occur in cells soon after they become attached to surfaces. These changes appear to enhance the metabolic activity of the adherent population.Item Role of Bacterial Exopolymers in the Deterioration of Metallic Copper Surfaces(1986) Geesey, Gill G.; Mittelman, M. W.; Iwaoka, Teika; Griffiths, Peter R.Item Binding of Metal Ions by Extracellular Polymers of Biofilm Bacteria(1988-11) Geesey, Gill G.; Jang, Larry K.; Jolley, John G.; Hankins, Michael R.; Iwaoka, Teika; Griffiths, Peter R.Exopolymers which anchor sessile bacteria to metallic surfaces exhibit the capacity to bind copper ions with high affinity. Ionized carboxyl groups on the polymers appear to participate in cupric ion binding. Formation of complexes between the polymers and cupric ions results in the release of protons from the polymer molecule. Attenuated total reflectance Fourier transform infrared spectroscopy showed that polymers composed of acidic polysaccharides promote ionization and deterioration of metallic copper surfaces. X-ray photoelectron spectroscopy studies revealed that the ionic state of the surface-derived copper varied depending on the type of acidic polysaccharide that was in contact with the surface. The results suggest that exopolymers elaborated by adherent bacteria can enhance corrosion of the surfaces with which they are associated.Item Copper Coated Cylindrical Internal Reflection Elements for Investigating Interfacial Phenomena(1986-09) Iwaoka, Teika; Griffiths, Peter R.; Kitasako, J. T.; Geesey, Gill G.Techniques for coating thin copper films on the surface of cylindrical germanium internal reflection elements are described. These films were then characterized in an aqueous environment. The expected exponential relationship between the depth of penetration of the evanescent wave into water and the thickness of the copper film was verified experimentally. The stability of vacuum-deposited copper coatings was strong enough that the internal reflection element could be exposed to an aqueous solution of a polysaccharide for more than 40 h. The weak adhesion of polysaccharides to copper surfaces was studied spectroscopically.Item Reversible Acceleration of the Corrosion of AISI 304 Stainless Steel Exposed to Seawater Induced by Growth and Secretions of the Marine Bacterium Vibrio natriegens(1986-04) Nivens, David E.; Nichols, P. D.; Henson, J. M.; Geesey, Gill G.; White, D. C.Item The Microphysiology of Consortia Within Adherent Bacterial Populations(1986-08) Geesey, Gill G.; Costerton, J. WilliamItem Bacterial Biofilms in Relation to Internal Corrosion Monitoring and Biocide Strategies(1988) Costerton, J. William; Geesey, Gill G.; Jones, P. A.This paper is a review of leading research in the field of bacterial corrosion monitoring with specific emphasis on systems that transport liquids rather than gases. However, the principles of bacterial corrosion presented below are universal and independent of whatever media is transported through the pipeline. It has now been established that the primary mechanism of bacterial corrosion of metal surfaces involves the creation, within an adherent biofilm, of local physiochemical ''corrosion cells''. The practical consequence of this perception is that we now know that bacteria must be in sustained contact with a metal surface, in well-organized microbial communities before the corrosion process is initiated. Decades of research in Aquatic Microbiology have shown that numbers and types of planktonic (floating) bacteria bear little relationship to the numbers and types of sessile (adherent) bacteria in biofilms in the same system, and that planktonic bacteria are much more susceptible to antibacterial agents than are their sessile counterparts.Item Application of epifluorescence microscopy to the enumeration of aquatic bacterial concentrated on membrane filters(1981) Geesey, Gill G.; Costerton, J. WilliamItem In situ, real time ft-ir/cir/atr study of the biocorrosion of copper by gum arabic, alginic acid, bacterial culture supernatant and pseudomonas atlantica exopolymer(1989-08) Jolley, John G.; Geesey, Gill G.; Hankins, Michael R.; Wright, Randy B.; Wichlacz, Paul L.Thin films (2.0 nm) of copper on germanium internal reflection elements (IREs) were exposed to 10% gum arabic (aqueous solution), 2% alginic acid (aqueous solution), 1% bacterial culture supernatant (BCS, simulated seawater solution), and 0.5% Pseudomonas atlantica exopolymer (simulated seawater solution) and monitored in situ, real time, with the use of Fourier transform infrared/cylindrical internal reflection/attenuated total reflection spectroscopy as a function of time at ambient conditions. Ancillary graphite furnace atomic absorption spectroscopy was used to monitor the removal process of the copper thin film from the germanium IREs. Results indicate that some of the copper was removed from the Cu/Ge interface by all four polymers and incorporated into the polymer matrix. Thus, biocorrosion of copper was exhibited by the four polymers in the order of alginic acid < gum arabic < BCS > Pseudomonas atlantica exopolymer. The FT-IR/CIR/ATR technique can be successfully used to monitor biocorrosion systems in in situ, real-time settings.
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