> Dear All: I recently synthesized a 17 mer (1R, 3K, 3Y, 1D, 2E, 1S, 1T, 1N, 1P,
> 2V, 1A), acetylated at the N-terminus using acetylimidazole, C-terminus was
> amidated. Synthesis looked normal, as did the yields of the crude peptide.
> Analytical HPLC showed two close peaks, I took the major one to be N-blocked (it
> was). However, the mass is +40 of the expected, any ideas?? Thanks in advance
> for the wisdom, Gautam Sarath
Dear Gautam, maybe you had extra acetylation at N epsilon of one of the Lys or
O of Ser.
------------------------------------------------------
Marcelo Valle de Sousa
Brazilian Center for Protein Research and Services - CBSP
Laboratory of Protein Chemistry and Biochemistry
Departament of Cell Biology
University of Brasilia
Brasilia - DF Brazil
CEP 70910-900
Tel: (55)(61)307-2142
Fax: (55)(61)272-4548
e-mail: mvsousa@unb.br
http://www.unb.br/cbsp
------------------------------------------------------