Chromatographic separation of the H
: BV oxidoreductase activity on a Superdex-S200 column. A. A representative elution profile of the enriched H2: BV oxidoreductase enzyme activity after size exclusion chromatography on Superdex-S200 is shown. The absorbance at 280 nm was monitored and the two main elution peaks were labelled P1 and P2. B. Samples of the fractions across the elution peaks P1 and P2 were separated by non-denaturing PAGE and subsequently stained for hydrogenase enzyme activity. Lane 1, crude cell extract (50 μg protein); lane 2, membrane fraction (50 μg protein); lane 3, solubilised membrane fraction (50 μg protein); lane 4, aliquot of the 400 mM fraction from the Q-sepharose column. The arrow identifies the H2: BV oxidoreductase enzyme activity.