An improved smaller biotin ligase for BioID proximity labeling

The BioID method uses a promiscuous biotin ligase to detect protein-protein associations as well as proximate proteins in living cells. Here we report improvements to the BioID method centered on BioID2, a substantially smaller promiscuous biotin ligase. BioID2 enables more-selective targeting of fusion proteins, requires less biotin supplementation, and exhibits enhanced labeling of proximate proteins. Thus BioID2 improves the efficiency of screening for protein-protein associations. We also demonstrate that the biotinylation range of BioID2 can be considerably modulated using flexible linkers, thus enabling application-specific adjustment of the biotin-labeling radius.

• NI
  National Institutes of Health

  Awards: P20GM103548, P20GM103620
• NI
  National Institute of General Medical Sciences

  Awards: P20GM103620, P20GM103548