which enzymes are processive?

Vadim Kraynov vkraynov at pop.service.ohio-state.edu
Tue Jun 3 21:43:41 EST 1997


In article <338DED79.53CE at usc.edu>, adleman at usc.edu wrote:
>We are interested in enzyme processivity. 
>
>1. We know that polymerases are processive.
>Though in this regard, which DNA-polymerases incorporate the most 
>nucleotides before falling off? 

If the processivity = kcat/koff, then - most processive are the replicative 
enzymes - T7 Pol, T4 Pol, E.coli Pol III, mammalian pol alpha.  For T7 Pol 
processivity is around 1500 nt/binding event.
Repair polymerases are significantly less processive (pol beta - 3-30 
nt/binding, and is often considered a distributive enzyme).

>
>2. Are some restriction enzymes processive?

Meaning ?  Restriction enzyme is supposed to make a SINGLE cut per binding 
event, right ?

>
>3. Are some ligases processive?

Same with ligases

>
>4. Are there any other processive enzymes?

Any polymerase ? (Procesivity >/ 1 )

>
>Thanks
>Len Adleman
>USC
>adleman at cs.usc.edu



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