Immunodetection of the hydrogenase large subunit (HupL) in TnHB100-containing strains. The immunoblot shows bands immunoreactive with antiserum raised against B. japonicum HupL in bacteroid crude extracts resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis on a 10% acrylamide gel. Numbers on the left of the panel indicate the molecular masses of unprocessed (66-kDa) and processed (65-kDa) forms of hydrogenase large subunit as deduced from the comparison to standard molecular mass markers. Strains: R. leguminosarum bv. viciae UPM791 (lane 1), PRE (lane 2), PRE-H4 (lane 3), UML2 (lane 4), and UML2-H3 (lane 5); R. etli CE3 (lane 6), CE3-H7 (lane 7), and CE3-H71 (lane 8); S. meliloti 102F34 (lane 9) and 102F34-H3 (lane 10); M. loti U226 (lane 11) and U226-H3 (lane 12).