Fig. (3) The protein exit tunnel of the ribosomal 50S subunit of the archaeon Haloarcula marismortui. View from the base of the 50S subunit in the absence (A) or the presence (B) of the macrolide carbomycin (red spacefill in (B)). The rRNA (pink) and ribosomal proteins (magenta, blue or green) are in ribbons. The figure was reproduced from [23] with permission.