This sequence was updated recently to reflect information that is a closer approximation to published information and purchased goods. For instance, the MW of this protein is ~14kDa, as this is Lysozyme "C" which likely is purchased from comercial sources, and the pI of this has been reported as between 10.6 and 10.9, however this may be the pI under native conditions. See http://www.roche-applied-science.com/ Roche catalog# 10 837 059 001 . The estimated pI of this sequence (post-alkylation!) is 10.46. If you do not specifiy alkylation for basic proteins, at this pH you can expect much more disulphide exchange to be occurring and a lower pI will be observed.
(Also, pKa values may be affected in the presence of Urea, possibly tending toward pH 7. This affect may not have been taken into account in assignment/determination of pKa values for basic functional groups in references [2,3]. If you are uncertain of using the default pKa values listed in these references or noted on the previous page, please input your own pKa values for these functional groups.)
Sample sequence: Lysozyme
Obtained from the ExPasy server(identical to sequence of Roche Catalog 10 837 059 001)
UniProtKB/Swiss-Prot Entry: P00698
Sequence(mature peptide:129 amino acids):
KVFGRCELAAAMKRHGLDNYRGYSLGNWVCAAKFESNFNTQATNRNT
DGSTDYGILQINSRWWCNDGRTPGSRNLCNIPCSALLSSDITASVNCAK
KIVSDGNGMNAWVAWRNRCKGTDVQAWIRGCRL
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