HM bases needed around rest. enz. sites for cutting

[jjw at rsbs0.anu.oz]

Hello Netlanders,
	I've just spent a little time designing some oligo primers
to use in some PCR reactions for generating fragments with specific
restriction sites on the ends.  I searched high and low for information 
on what the minimum number of bases around a recognition site different
R. enzymmes need for correct and efficient cutting. I found a reference on 
primer design for this purpose in a book on PCR which glibbly advises one 
to include a few extra bases 5'- to the restriction site being introduced
but give no real info on how many are needed for which enzymees. So this 
I did and sent the sequences off to the university facillity for 
construction. Then I sat back and thought how nice it would be to have had
the info. I needed; hence, this note.
	So much for the intro. I remember seeing *years ago!* some chart
or table which had this sort of info. neatly listed. ie. - how many flanking
nucleotides around a restriction site different R. enzymes need. Of course,
I now don't remember where I saw this snippet of information.  Does anybody
out there remember where this table came out? Or where this info might be 
obtained?  I think that the table I remember seeing was designed for the 
purpose of ensuring multiple enzyme digestions were compatible (ie. sites 
not too close together), but in this day and age this type of info. has 
great value in PCR primer design.  
	So, ten brownie points for those with great memories who reply!
Any many thanks in advance to those who don't remember the table I so dimly
recall but who can suggest a likely souce of information.

			Cheers!


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Jeremy Weinman		Plant Microbe Interaction group
			Research School of Biological Sciences
			Australian National University

	Email:		jjw at rsbs0.anu.oz
	Phone:		61 6 2495051
	Fax:		61 6 2490754		
	Snail:		PO Box 475, Canberra, ACT 2601, AUSTRALIA

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