Does RNA - PCR ??

[Duncan Clark]

In article: <DBxnyo.Gn3 at midway.uchicago.edu>  rmoldwin at midway.uchicago.edu writes:

> I also have seen several reports of RT activity in Taq.  Perhaps, it varies 
> according to the manufacturer, and the specific origin of the Taq, e.g. 
> recombinant/modified vs. wild type.  In my lab, we very rarely see this RT 
> activity when using standard Perkin Elmer recombinant AmpliTaq, which PE 
> reports in their catalog to have "minimal, low" RT activity.  AmpliTaq is 
> modified from the wild-type Taq, but I can't determine what the difference is 
> from their literature.

AmpliTaq is not modified at the aa level just a recombinant version with 
modified codon usage. It has the same level of RT activity ie low.

As far as I am aware all thermus polymerases show a level of RT activity, but
some are better than others ie Tth from Thermus thermophilus HB8. Most have
an extremely poor level of RT activity. 

On a similar note all thermus pols have the terminal transferase activity ie
they add a single base to the 5' end of the PCR product which is usually (but
not always) a T.

Duncan   

 
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My mind's made up. Don't confuse me with the facts!