STP1235

    Mechanisms of Heavy Metal Uptake in a Mixed Microbial Ecosystem

    Published: Jan 1995


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    Abstract

    The potential use of a mixed microbial ecosystem for the bioremediation, and removal of heavy metals from contaminated water and soil was investigated. The study included the development of metal-tolerant microbial strains for increased metal recovery, and the investigation of the uptake dynamics of (CrVI), Pb, and Se. The results indicated that the microbial growth dynamics towards a stable mat structure resulted in a typical two microbial phase pattern: (1) a mixed bacterial bloom, during which the metal ions were enzymatically detoxified, and mobilized towards the pond surface, and (2) a cyanobacterial phase, a period marked by the stabilization of the metal species in the floating microbial mat. Investigation of the bioremediation processes suggested that reduction by microbial sulfate reactions, precipitation of metal ions, adsorption at bacterial membrane sites, reduction by change of oxidation states, and chelation played major roles in describing the strategies of bacterial response to the heavy metals investigated.

    Keywords:

    heavy metals, microbial mat, ecosystem, bacterial bloom, cyanobacteria, simulated pond


    Author Information:

    Ibeanusi, VM
    Professor, Center for Scientific Applications of Mathematics (CSAM), Spelman College, Atlanta, GA

    Archibold, EA
    Professor, Morehouse College, Atlanta, GA


    Paper ID: STP13036S

    Committee/Subcommittee: F20.24

    DOI: 10.1520/STP13036S


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