Recombinant protein expression in E. coli. Ten GST-tagged C. pneumoniae recombinant proteins (A) were loaded in equal amounts of total protein from crude lysates in each lane and subjected to SDS-PAGE and coomassie staining (B). Additionally the same crude lysates were examined by SDS-PAGE and western blotting (C). The given protein sizes are already calculated for GST-fusion proteins. The arrows indicate the recombinant proteins.