TABLE 3.

Results of PCRs assessing the BTEX-catabolic gene compositions in the in situ mesocosm material and aquifer samples obtained at different time points^a

Primer pair (detected gene family)	PCR result for uncontaminated area A0							PCR result for contaminated area A1
	Sterile A0Z material	Nonsterile A0Z material		Nonsterile A0Z material in mesocosms in well PV8811				Nonsterile A0Z material in mesocosms in well PV8809				Sterile A0Z material in mesocosms in well PV8810				A1Z material
	Jan 9	Jan 9	May 20	Jan 16	Jan 30	March 10	May 20	Jan 16	Jan 30	March 10	May 20	Jan 16	Jan 30	March 10	May 20	May 20
TBMD-F/TBMD-R (tbmD)	−	−	−	−	−	−	−	(+)	(+)	−	−	−	−	−	−	−
TMOA-F/TMOA-R (tmoA)	−	++	++	++	++	++	++	++	++	++	++	++	++	++	++	++
TOL-F/TOL-R (xylM)	−	−	−	−	−	−	−	+	+	+	+	+	+	+	+	+
XYLE-F/XYLE-R (xylEl)	−	−	−	−	−	−	−	+	+	+	+	+	+	+	+	+

^aAll sample data were from 2003. ++, strong signal; +, signal; (+), weak signal; −, no signal. No signals were obtained with the primer sets XYLA-F/XYLA-R (xylA), TODC1-F/TODC1-R (todC1), XYLE2-F/XYLE2-R (xylE2), TBUE-F/TBUE-R (tbuE), TODE-F/TODE-R (todE), and CDO-F/CDO-R (cdo).