Extended Data Fig. 5: Histidine intermediate in SdeA catalysis.
From: Insights into catalysis and function of phosphoribosyl-linked serine ubiquitination
a, In vitro ubiquitination reactions by various SdeA213–907 PDE site histidine mutants probed by Coomassie-stained SDS–PAGE. b, High-energy HCD fragmentation was used to generate fragments of the peptide backbone. We could identify multiple fragments of SdeA275–284 and Ub34–48, to further validate the identity of the bridged active site. c, In vitro ubiquitination reaction by SdeA213–907(H407N) mutant using rhodamine-labelled ubiquitin. d, In vitro ubiquitination reaction using HA-tagged ubiquitin. e, In vitro ubiquitination reaction by SdeA213–907(H407N) without and with heating probed by phosphostain. f, In vitro ubiquitination reaction using HA–ubiquitin by various PDE mutants. These experiments were repeated independently twice with similar results. For gel source data, see Supplementary Fig. 1.
