Mwatson's 20 kbp PCR question.
cenobite at welchlink.welch.jhu.edu
Fri Aug 26 16:15:49 EST 1994
In article <aquilla.1126944584M at sadye.emba.uvm.edu>,
Tracy Aquilla <aquilla at salus.med.uvm.edu> wrote:
>In Article <1994Jul27.224302.5558 at news.cs.brandeis.edu>,
>story at binah.cc.brandeis.edu wrote:
>>One thing you should try for 20 kb PCR which is new on the market is PCR
>>extender additive from Stratagene. They will undoubtedly gove you a free sample
>>if you ask them. It's amazing stuff.
>>Also try the group bionet.molbio.methds-reagnts for ongoing discussion of the
>>topic of long range PCR.
>>story at binah.cc.brandeis.edu
>I just called, and they're not giving it away for free any more. Bummer!
Hmmmm, I'm truely curious as to the contents of the Extender, but
if you are interested in doing long range PCR, then get KlenTaq1 from a
Ab Peptides, Inc.
6272 Marmaduke Ave.
St. Louis, MO 63139
Tel (314) 644-1700
Fax (314) 644-2100
This enzyme, according to their info sheet, is Taq poly, without some of
the N-terminus. So it loses its 5' exo domain. When they originally
marketed this enzyme, they were bundling it with Pfu from Stratagene,
mixing it in a 1:6 (Pfu:KlenTaq1) ratio (by unit). Then I guess they got
sued for selling Stratagene enzymes and they stopped selling the mix (I
think they were calling it KlenTaqLA). The reason for mixing the two is
that KlenTaq1 cannot proofread, yet Pfu has a much lower processivity and
falls off, so working in tandem ...
Someone in my lab used the stuff to PCR genomic inserts out of
EMBL3. The PCR was very specific and yielded a 12.5-13 Kb band. Not
bad, huh! So I wonder if Taq Extender (tm) is actually a thermophillic
poly that is more processive than Pfu.
Hope this helps.
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