TABLE 5.

AmpliTaq Gold and rTth DNA polymerase detection sensitivity in water and in the presence of PIgG and effects of heating of PIgG and L. monocytogenes DNA together and adding bacteriophage λ DNA^a

Amt of L. monocytogenes DNA (g)/reaction tube	PCR resultb
	Water		IgGc		Heated IgG, AmpliTaqd	Heated IgG and DNAe		IgG and λ DNA,f AmpliTaq
	AmpliTaq	rTth	AmpliTaq	rTth		AmpliTaq	rTth
10−6	+	+	+	+	+	+	+	+
10−7	+	+	+	+	+	−	+	+
10−8	+	+	−	+	+	−	−	+
10−9	+	+	−	±	±	−	−	+
10−10	+	+	−	−	−	−	−	+
10−11	+	+	−	−	−	−	−	+
10−12	−	−	−	−	−	−	−	−

^aAbility of AmpliTaq Gold and rTth DNA polymerases to amplify different concentrations of L. monocytogenes DNA in water and in the presence of 0.41 μg PIgG and the effects of heating PIgG together with different concentrations of L. monocytogenes DNA and the addition of 1.25 ng of bacteriophage λ DNA on the detection level. 

^bPCR results: +, band of high intensity; ±, band of low intensity; −, no band. 

^cPCR detection in the presence of 0.41 μg of PIgG. 

^dPCR detection in the presence of 0.41 μg of PIgG heated at 95°C for 10 min. 

^ePCR detection in the presence of 0.41 μg of PIgG heated together with L. monocytogenes DNA at 95°C for 10 min. 

^fPCR detection in the presence of 0.41 μg of PIgG and 1.25 ng of bacteriophage λ DNA.