%0 Journal Article
%A Burke, Meghan
C.
%A Wang, Yan
%A Lee, Amanda E.
%A Dixon, Emma Kimm
%A Castaneda, Carlos A.
%A Fushman, David
%A Fenselau, Catherine
%D 2015
%T Unexpected Trypsin Cleavage at Ubiquitinated Lysines
%U https://acs.figshare.com/articles/journal_contribution/Unexpected_Trypsin_Cleavage_at_Ubiquitinated_Lysines/2052732
%R 10.1021/acs.analchem.5b01960.s001
%2 https://acs.figshare.com/ndownloader/files/3624084
%K K 48 residues
%K trimer
%K Lys 48. Trypsin
%K R 74
%K ubiquitin
%K peptide products
%K tryptic conditions
%K Ubiquitinated LysinesUnexpected tryptic cleavage
%K Initial cleavage
%K tryptic products
%K Unexpected Trypsin Cleavage
%X Unexpected tryptic
cleavage has been characterized at modified
K48 residues in polyubiquitins. In particular, the tryptic products
of all seven of the lysine-linked dimers of ubiquitin and of three
trimerslinear Ub–48Ub–48Ub, linear Ub–63Ub–63Ub, and
the branched trimer [Ub]2–6,48Ubhave
been analyzed. In addition to the peptide products expected under
commonly used tryptic conditions, we observe that peptides are formed
with an unexpected ε-glycinylglycinyl-Lys carboxyl terminus
when the site of linkage is Lys48. Trypsin from three different commercial
sources exhibited this aberration. Initial cleavage at R74 is proposed
in a distal ubiquitin to produce a glycinylglycinyl-lysine residue
which is bound by trypsin.
%I ACS Publications