Table 1.

Characteristics of sediment and aquifer samples used as starting material for DNA extraction and anaerobic microcosms and test resultsa

Site of sample collectionContaminantsDate of sample collection (mo/yr)Amplification of 16S rDNA fragmentsEnd product(s) of PCE dechlorination in microcosms, with electron donorb:
Initial PCR, universal primersSecond PCRAcetateHydrogen
BB1-targeted primersDehalococcoides-targeted primers
Bachman 1AtPCE, TCE,cis-DCE8/1997ccis-DCEPCEe
Bachman 1BbPCE, TCE,cis-DCE8/1997+dcis-DCEPCEe
Bachman 2AtPCE, TCE,cis-DCE8/1997+dcis-DCEPCEe
Bachman 2BbPCE, TCE,cis-DCE8/1997+dcis-DCEPCEe
Bachman ANone8/1997PCEePCEe
Bachman DNone8/1997PCEePCEe
Cape CanaveralChloroethenes9/1998cis-DCE
Jacksonville MW 510PCE, TCE (dissolved plume)6/1998++PCEeVC, ETH
Jacksonville IW001PCE, TCE (source area)6/1998PCEePCEe
B & J Industrial, sites C and DPCE, TCE, BTEXf7/1998PCEePCEe
SchoolcraftChlorinated solvents1995, 1998PCEePCEe
Red Cedar RiverNone7/1995, 5/1998, 11/1998+++cis-DCEETH
Père Marquette RiverNone4/1995, 9/1998+++cis-DCEETH
Au Sable RiverNone5/1995, 5/1997+++cis-DCEETH
  • a DNA was isolated by using the UltraClean Soil DNA Kit from Mo Bio Laboratories, Inc. Microcosms were amended with PCE and acetate or hydrogen as the electron donor.

  • b Microcosms were analyzed after 10 weeks of incubation, and the major end products (>90% of the initial PCE concentration) are given. VC, vinyl chloride; ETH, ethene.

  • c −, no visible bands were obtained in the initial amplification with universal primers. The initial PCR, however, yielded PCR-amplifiable DNA, as confirmed in a control experiment with a pair of universal internal primers.

  • d Location 1Bb tested positive when DNA was extracted from fresh aquifer material. In addition, location 2Bb tested positive when an alternate DNA extraction method was used, and locations 2Bb and 2At tested positive after enrichment.

  • e Less than 5% of the initial amount of PCE was dechlorinated to TCE and cis-DCE.

  • f BTEX, benzene, toluene, ethylbenzene, and xylenes.