Purification of rHtrA proteins. Each rHtrA protein (rHtrA1 in a and rHtrA2 in b), after production and secretion in L. lactis (by either strain MG1363(pVE8126) in a or strain MG1363(pVE8127) in b) grown in fermenter as described in Figure 3, was purified by affinity. At each purification step, an SDS-PAGE analysis followed by Coomassie Brilliant Blue staining was performed. Lane 1 concentrated supernatant from an induced culture after growth in fermenter, Lane 2 flow through, Lanes 3 and 4 washing number 1 and 2, Lanes
5–7 elution fractions number 1–3. MWM molecular weight marker.