ia a course on protein and peptide analysis for biochemistry students we
perform the same experiments that you discribed using pure
beta-lactoglobulin from Sigma as the unknown protein. We also observe that
without reduction about 5% of the protein carries two instead of one
acetamide groups and after reduction about 10% of the protein carries 6
instead of 5 acetamide groups. We didn't looked at this very closely. Could
it be that one gets a slow alkylation of a Lys residue that has a somewhat
lower pK than all the others?
many regards
Peter
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Dr. Peter Hunziker | E-Mail: phunzi@bioc.unizh.ch
Universitaet Zuerich |
Biochemisches Institut | Tel: +41-1-635 55 20
Winterthurerstr. 190 | Fax: +41-1-635 68 05
CH-8057 Zuerich, Switzerland |
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Visit our department homepage: http://www.unizh.ch/biochem
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