Re: Extraction of a phosphopeptide

Young Moo Lee (ymlee@ucdavis.edu)
Fri, 24 Apr 1998 16:35:27 -0700 (PDT)

Dear Satya:

You may want try 0.05 to 0.1% SDS extraction (2x, 30 to 60 min each)
followed by acetonitrile. SDS can be removed easily by adding guanidinium
HCl and centrifugation to remove the precipitated guanidinium
dodecylsulfate. If the excess guanidine HCl interferes your analysis, it
can be removed by a short C4 column (hope your 3k peptide elutes). SDS can
be also removed by organic solvent partitioning (Hwang et al. J.
Chromatogr. B 686 (1996) 165-175). SDS extraction works well for aggregated
hydrophobic and/or large peptides in my experiences.

-Young Moo Lee

You wrote:
>Dear friends,
>We have isolated a 3KD peptide and have phosphorylated this with P32.
>We tried to extract the peptide from SDS gels using 60% acetonitrile +
>0.1% TFA but could be able to extract only about 10% radioactivity. Is
>there any other better extraction procedure available? We plan to try
>electroelution as a last choice.
>Thanks in advance for your suggestions
>
>Satya Yadav
>Lerner Research Institute
>The Cleveland Clinic Foundation
>Cleveland, Ohio

____

Young Moo Lee, Ph.D.
Director
Protein Structure Laboratory
University of California
Davis, California 95616-8656
530-752-4328 (voice)
530-752-8969 (fax)
ymlee@ucdavis.edu

http://pubweb.ucdavis.edu/Documents/psl/psl_pg.htm