Streptavidin and Biotin interactions

Toumy Guettouche tguettou at
Mon Feb 10 16:37:40 EST 1997

On 9 Feb 1997, Diane Webster wrote:

> Hi,
> I am currently using biotin labelled oligo(dT) to capture my 
> polyA tail potyvirus in streptavidin coated tubes for RT-PCR 
> (Boehringer Mannheim's mRNA capture kit).
> I would like to know more about how streptavidin and biotin interact.
>   Specifically do they dissociate when heated during PCR (94 C)? 
> And does the oligo(dT) dissociate from the biotin label during PCR?
> General related details on streptavidin and biotin would be useful
> Thanks in advance
> Diane
> Diane at
> Botany Department
> University of Otago
> PO Box 56
> Dunedin
> New Zealand 
Hi Diane,

The interaction between Biotin (Vitamin) and Avidin (protein) is one of 
the strongest known in biological systems. It is stronger than any 
antibody/antigen interaction. You are using streptavidin which lacks a 
glycosylation site thereby decreasing nonspecific binding. Since avidin 
is a protein, it will be denatured during PCR and therefore release 
biotin. I don't know if it will bind Biotin again, when you lower the 
temperature during the cycle, but I doubt it. Biotin is fairly stable and 
since it is covalently attached to your oligo it should not come off. You 
can also check its temp stability in the Merck index or call the company 
you bought it from.
BTW there is a lot of literature about this out there. A lot of companies 
have handbooks describing the interaction and properties (e.g. Pierce).
 Hope that helps


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