Protein Isoeletric point calculation

Flip Hoedemaeker, CvF RUL/TNO, Leiden, The Netherlands sbtnfh at
Tue Sep 13 04:13:14 EST 1994

In article <Pine.SUN.3.90.940912131219.3226A-100000 at>, szeinfel at SNFMA1.IF.USP.BR (Rafael Iosef Najmanovich Szeinfeld {S) writes:
>	Hi All,
>	I read a recent message about Proteins Isoeletric point (PIP) and the 
>replayer said something about a progam that calculates PIP's so I'll like 
>someone to say something about the method used for such calculations...

Hi Rafael,

I don't want to disappoint you, but pI calculation is very diificult. You
have to take into account which amino acids are on the protein surface,
becauce their pK's are important for the charge of the protein. I've asked
Gert Vriend and the biocomputing group at the EMBL in Heidelberg just the same
question about a year ago. He said that at the time they were very busy with a
whole team to come up with a suitable algorithm, but that it could take quite
some time still. I don't know how far they are now, you'll have to ask him
(Gert.Vriend at Still you would need the 3D coordinates of
your protein. With other methods you'll end up with a pI, but it won't be very


More information about the Proteins mailing list