Department chemists makes cover story of journal ChemBioChem

2006 April: Associate Professor Knud J. Jensen, Ph.D. Malene Brandt et al. has made the cover of ChemBioChem with their article "On-Bead Chemical Synthesis and Display of Phosphopeptides for Affinity Pull-Down Proteomics" ( article link)

 

Knud J. Jensen explains: We describe a new method for phosphopeptide proteomics based on the solid-phase synthesis of phosphopeptides on beads suitable for affinity pull-down experiments. Peptide sequences containing the Bad Ser112 and Ser136 phosphorylation motifs were used as bait in affinity pull-down experiments to determine their ability to bind 14-3-3 proteins.

 

Support-bound peptides were assembled directly on the solid support (PEGA) by standard solid-phase synthesis through a BAL-type handle. The peptides were varied in length and sequence. This synthetic strategy also allowed introduction of a soft electrophile (aldehyde) at the C terminus for potential activity-based proteomics. The synthetic support-bound Bad phosphopeptides were able to pull down 14-3-3.

 

 

Furthermore, Bad phosphopeptides bound endogenous 14-3-3 proteins, and all seven members of the 14-3-3 family were identified by mass spectrometry. In control experiments, none of the unphosphorylated Bad peptides bound transfected 14-3-3 or endogenous 14-3-3. We conclude that the combined synthesis and display of phosphopeptides on-bead is a fast and efficient method for affinity pull-down proteomics.