FIG. 4.

Copy numbers determined by qPCR of vcrA, tceA, and Dehalococcoides 16S rRNA genes in parallel 50-fold-diluted ANAS subcultures. Inoculum, dilution culture at time zero; Starved, culture incubated for 2 months in the absence of solvent; VC to Eth, the culture was fed VC and allowed to dechlorinate to ethene; TCE to cDCE, the culture was fed TCE and limited to dechlorination to DCE by flushing and refeeding as soon as VC was detected. The ratio of vcrA to tceA in each sample is shown above each set of columns. Note that a linear scale is used for copy numbers.