Figure 4. Purification of endogenously expressed CorA.

a) SDS-PAGE analysis of fractions obtained after the (NH₄)₂SO₄ precipitation of the CorA-containing NaCl extract (see M&M). A 12.5% PA-gel was used and stained with Coomassie Brilliant Blue R-250. Lane 1, PD10 desalted NaCl extract from the M. album BG8 outer membrane; lane 2, solubilized precipitated material after 50% (NH₄)₂SO₄ precipitation of 1); lane 3, The soluble fraction after 50% (NH₄)₂SO₄ precipitation of 1). b) A representative chromatogram of the anion exchanger elution profile of the (NH₄)₂SO₄-treated NaCl extract. Elution of CorA is indicated with an arrowhead. c) A representative gel filtration chromatogram of pooled CorA-containing fractions obtained in the anion exchanger chromatography. d) SDS-PAGE analysis of pooled fractions containing CorA obtained from the ion exchanger chromatography (lane 1), and the gel filtration (lane 2). CorA and molecular mass markers are indicated.