Re: [ccp4bb]: expression of highly basic protein

[Artem Evdokimov]

The pI by itself should not cause too many problems. Make sure that a) your codon counts and distribution are good (especially for the rare R codons if you have them) and that b) you do not have too many potential proteolytic sites (quite a few proteases clip after or near clusters of basic residues).   When you do express your stuff, don't be surprised if it comes out all stuck to DNA. Judicious use of either DNAse or non-disruptive lysis (such as offered by e.g. B-PER) should result in improvement.   Artem Evdokimov ex-PGP ----- Original Message ----- From: Yadong Yu To: ccp4bb@dl.ac.uk Sent: Monday, March 13, 2006 6:38 PM Subject: [ccp4bb]: _expression_ of highly basic protein Hi, Sorry for this off-topic. I have a highly basic protein, whose pI is over 11. I don't know if its pI causes the difference of _expression_ in E.coli pET system. Anyone has general experience of expressing such proteins? Thanks! Yadong Yu LCMN/NICHD/NIH Bldg 35, Room 3B 1006 35 Lincoln Drive Bethesda MD 20892 (301)496-9347 Fax (301)496-2396 [EMAIL PROTECTED]