Accession Number : ADA266115


Title :   Biotransformation of Toxic Metals by Bacteria


Descriptive Note : Annual rept. 1 May 1992-30 Apr 1993


Corporate Author : MEHARRY MEDICAL COLL NASHVILLE TN


Personal Author(s) : Blake II, Robert,


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a266115.pdf


Report Date : 31 May 1993


Pagination or Media Count : 5


Abstract : The aims of this research are to study each of the various molecular mechanisms whereby toxic metal cations and oxyanions are chemically transformed by bacteria that live in the soil. The research effort for the current year has focused on the Xanthomonas-dependent transformations of selenium and lead. Conversion of selenite and ionic lead into insoluble biocolloids was found to occur widely in the genus Xanthomonas. The resulting biocolloids were shown to bear negative charges derived from biological polymers associated with the metals in the colloid. The formation of a lead biocolloid was accomplished from a lead-citrate complex where citrate was the sole carbon source for the bacterium. These observations could prove useful for the eventual exploitation of Xanthomonas and related genera for the removal of toxic wastes from selected, heavily polluted sites.


Descriptors :   *POLYMERS , *SOIL MECHANICS , *SOIL STRUCTURE INTERACTIONS , *SELENIUM , *CHEMICAL REACTIONS , *LEAD(METAL) , INDUSTRIES , WASTES , COLLOIDS , WASTE TREATMENT


Subject Categories : Microbiology
      Solid Wastes Pollution and Control
      Environmental Health and Safety


Distribution Statement : APPROVED FOR PUBLIC RELEASE