Purification of Recombinant WT A3A Protein

The WT A3A was purified as described in Sharma et al. (2015) (link). Briefly, Rosetta 2(DE3)pLysS E. coli (EMD Millipore, Burlington, MA, USA) transformed with a bacterial expression construct for C-terminal His₆-tagged WT A3A was grown in Luria broth at 37 °C. The cells were induced for expression of the recombinant protein with 0.3 mM isopropyl β-D-1-thiogalactopyranoside and cultured overnight at 18 °C. A3A protein was purified from the lysates by affinity chromatography using the Ni-NTA His bind Resin (EMD Millipore).  The concentrated protein was stored in 25 mM Tris (pH 8.0) with 50 mM NaCl, 1 mM DTT, 5% v/v glycerol and 0.02% w/v sodium azide at −80 °C.