FIG. 1.

Relationship of Dehalococcoides cell titers to Aroclor 1260 dechlorination in JN subcultures. Dechlorination is presented as the percent decrease in PCB congeners with six to nine chlorines, which comprise ∼90% of the PCBs in Aroclor 1260. Data are means ± standard deviations. (a) PCB-dependent growth of Dehalococcoides in JN cultures incubated with Aroclor 1260 (50 μg/ml) and decrease of Dehalococcoides cell titers in cultures transferred four times without PCBs. (b) PCB-dependent growth in subcultures when PCBs were restored following three transfers without PCBs. (c) Correlation between PCB dechlorination and Dehalococcoides (Dhc) cell growth in replicate cultures B and C.