Fig. 3: Expression, purification, and conjugation of DogTag-HA6 and fPE-SnoopTagjr.

a DogTag-HA6 expression: 1–3 IPTG-induced lysate, 4–6 HB-PET auto-induction lysate, 7–9 IPTG-induced precipitate, 10–12 HB-PET auto-induction precipitate. b fPE-SnoopTagjr expression: 1–3 IPTG-induced lysate, 4–6 HB-PET auto-induction lysate, 7–9 IPTG-induced precipitate, 10–12 HB-PET auto-induction precipitate. c DogTag-HA6 purification: 1 elution peak, 2 20 mM imidazole elution, 3 100 mM imidazole elution, 4–5 250 mM imidazole elution. d fPE-SnoopTagjr purification: 1 elution peak, 2 20 mM imidazole elution, 3 100 mM imidazole elution, 4–5 250 mM imidazole elution. e Purification and conjugation of fPE-HA6: 1. Coupling in the free system 2. Purification of coupled enzymes 3. Washing of unreacted substrates in the coupled enzyme.