Problems with Promega Taq

[John Nash]

In article <Miao-030693075250 at fp1-molbio-13.uoregon.edu> Miao at oregon.uoregon.edu (Vivian Miao) writes:
>From: Miao at oregon.uoregon.edu (Vivian Miao)
>Subject: Re: Problems with Promega Taq
>Date: 3 Jun 1993 15:12:28 GMT

>By the way .....

>I've tried side by side tests with NEB's Vent (neither Deep nor
>Exo-) and it seems that for my setup, Taq makes a lot more
>product than Vent.  Before I elicit a host of questions from
>Andre  :-) .... the reactions are made up as a cocktail minus
>enzyme and its conc'd buffer stock which are added later, the
>same no. of units of enzyme are used, and reactions were run
>at the same time in the thermocycler;  I ran similar volumes of
>the reactions  on a gel and by inspection estimate that the product
>band from Taq is probably 3-4X brighter than that from Vent.  Is
>this within the range of variation, or is there something about 
>error correction by Vent that has a cost in yield?  I'm not knocking
> Vent (for some applications, like templates that require very high
> temperature denaturation, Vent is the only thing we've tried that
> works), but it seems that for routine work, (e.g. at 92-94C 
>denaturation, 45-55C annealing, 72C extension, 25-28 cycles)
>you get more product with Taq.  Comments?

In my hands, it's primer:template specific... Many of my PCRs make a similar 
amount of product whether it's Vent or Taq... a couple work better with 
Vent, and I have one combination which WON'T amplify with Vent, and I have 
the clone of the Taq-amplified product in my fridge!


  cheers, John

  John Nash                           | Email: Nash at biologysx.lan.nrc.ca.
  Institute for Biological Sciences   |
  National Research Council of Canada | Email to my other NRC accounts
  Ottawa, Ontario, Canada.            | is usually forwarded here.
	  *** Disclaimer:  All opinions are mine, not NRC's! ***