Purification of ACL proteins (SDS-PAGE). Lanes 1 and 6, standard markers; lane 2, purified recombinant CLS (approximately 0.9 μg); lane 3, purified recombinant CLL (approximately 0.8 μg); lane 4, reconstituted CLS and CLL (approximately 2.7 μg); lane 5, purified recombinant holo-ACL from coexpressed aclA and aclB on a single plasmid (approximately 2 μg).