Path: utzoo!utgpu!watserv1!watmath!uunet!bionet!agate!shelby!bu.edu!att!pacbell.com!ucsd!sdd.hp.com!zaphod.mps.ohio-state.edu!ub!boulder!binkley From: binkley@boulder.colorado.edu (Jon Binkley) Newsgroups: bionet.molbio.methds-reagnts Subject: Extra Sequence Needed for Restriction Enzymes Message-ID: <29607@boulder.Colorado.EDU> Date: 12 Nov 90 22:12:28 GMT Sender: news@boulder.Colorado.EDU Reply-To: binkley@boulder.colorado.edu (Jon Binkley) Organization: University of Colorado, Boulder Lines: 16 Nntp-Posting-Host: beagle.colorado.edu A while back someone asked for information about the minimum flanking sequence needed for cleavage by restriction enzymes. The new catalog from New England Biolabs ('90 - '91) has information for some commonly used enzymes. I don't have the time (or permission) to regurgitate the information, but it can be found on p. 132 of the catalog. The enzymes vary widely in their requirements. For example, EcoRI cut the sequence gGAATTCc (one extra base on either side of the recognition sequence) to >90% completion in a 2 hour incubation, while PstI cut the sequence tgcaCTGCAGtgca (four extra bases) to only 10% completion after a 20 hour incubation. Jon Binkley