Advantages of 33-P

[Dan Diaz]

In a previous article, jow at helix.nih.gov (Jim Owens) says:
>I have reasoned this way myself.  But is not the product with
>[35-S]dATP(alpha-S) that heat labile sulfate diester?  Why would this be
>more stable than one generated by 33-P decay?
>
>Perhaps the radiodecay of phosphorus to sulfur leads to the problem and
>not heat instability of the sulfate diester?  I believe the problem also
>occurs with 32-P -> 32-S.

Use of dATP(alpha-S) leads to the formation of phosphorothioates, whose
structure is:
               S
      5'-dN~ O P O ~dA-3'
               O

which is still a (thio)phosphate diester and not thermolabile, as are sulfate
diesters. 

diz