Taq polymerase vs HotstartTaq polymerase - (Jun/15/2006 )

HI!

My lab has been using HotstarTaq master mix from qiagen, but now we are thinking of buying another brand because it's cheaper. Does anyone have experience with eppendorfs HotstartMastermix?
Also, someone told me if i have DNA from dirty samples such as sewage/feces it might be better to use a "normal" polymerase mastermix instead of a hotstart, is this correct? I have some problems ampifying some DNA, especially with certain primers when using the HotstartTaq but I dont know if the enzyme is really to blame..

torunn

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Hi,

I've used HostartMastermix from Eppendorf! I think it worked quite well.

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Hi,

the sales representatives from Eppendorf & Qiagen told me a few days ago, that Qiagen & Eppendorf will merge. So Eppendorf reagents will not exist very long in future (only their hardware), but you get the Eppendorf stuff 25% off (at least in Germany). But other companies also sell Hotstart Taq....

Hope this helps
hobglobin

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Hotstart polymerases are modified versions of the original one, modified in such a way that they need a 5-10 minute activation prior to PCR, which is convenient for reducing aspecific amplification and room temperature set up. The downside is that they are less processive (they have some altered amino acid, those are the modifications). If you really need hotstart, maybe you can try some antibody mediated hotstart formulations (there's plenty of them, they are the same polymerase that's inactivated due to the presence of an antibody, destroyed during initial denaturation).
Otherwise: make your master mixes on ice, add your DNA and keep on ice, and then put your tubes in a prewarmed thermocyler and you have a hotstart PCR as well, working with your regular taq!

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Thanks for the replys! I ordered some yesterday. The salesperson hinted that even though eppendorf is being bought by Qiagen they will probably stick with the eppendorf polymerase+buffer, but he counldt make any promises.

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