TABLE 3.
Effects of different combinations of four amplification facilitators on amplification capacities of rTth and Taq DNA polymerases in the presence of blood, feces, and meat
| Polymerase and facilitator (facilitators concnc) | PCR resultsa with the following at the indicated concn (% [vol/vol])b:
|
||||||||
|---|---|---|---|---|---|---|---|---|---|
| Bloodd
|
Feces
|
Meat
|
|||||||
| 20 | 4 | 2 | 20 | 4 | 2 | 20 | 4 | 2 | |
| rTth | |||||||||
| BSA (0.4), gp32 (0.01) | −, − | +, + | +, + | +, + | +, + | +, + | |||
| Betaine (11.7), gp32 (0.01) | −, − | −, + | +, + | −, − | +, + | +, + | |||
| gp32 (0.01), proteinase inhibitor (1×) | −, − | −, − | −, − | −, − | +, + | +, + | |||
| BSA (0.4), betaine (11.7) | −, ± | +, + | +, + | +, + | +, + | +, + | |||
| BSA (0.4), proteinase inhibitor (1×) | −, − | +, + | +, + | −, − | +, + | +, + | |||
| Betaine (11.7), proteinase inhibitor (1×) | −, − | +, + | +, + | −, − | −, − | −, − | |||
| Taq | |||||||||
| BSA (0.4), gp32 (0.01) | −, − | +, + | +, + | −, − | +, + | +, + | +, − | +, + | +, + |
| Betaine (11.7), gp32 (0.01) | −, − | −, − | −, − | −, − | +, + | +, + | −, − | +, + | +, + |
| gp32 (0.01), proteinase inhibitor (1×) | −, − | −, − | −, − | −, − | −, − | −, − | −, − | +, − | +, − |
| BSA (0.4), betaine (11.7) | −, − | +, + | +, + | −, − | +, + | +, + | −, − | +, + | +, + |
| BSA (0.4), proteinase inhibitor (1×) | −, − | +, + | +, + | −, − | +, + | +, + | −, − | +, + | +, + |
| Betaine (11.7), proteinase inhibitor (1×) | −, − | +, + | +, + | −, − | −, − | −, − | −, − | −, + | −, + |
a
Results are of two independent PCRs; +, PCR product of high yield; ±, PCR product of low yield; −, no PCR product. The results were recorded in the same order in which the PCRs were done.
b
Percentage (vol/vol) of blood and homogenates of feces and meat in the PCR mixtures for rTth and Taq DNA polymerase containing 1 ng of L. monocytogenes DNA.
c
Percentage (wt/vol) of amplification facilitators in the reaction mixtures.
d
The polymerase rTth was able to amplify DNA in the presence of all concentrations of blood tested without the addition of any amplification facilitators.