Candidate attenuators upstream the leuS opreron in Streptomyces spp. a) Coordinates and protein identifiers of the leuS genes. b) Alignment of the attenuators. Start, leucine and stop codons are shown in bold. The terminator hairpins are highlighted in grey, the antiterminator hairpins are underlined. The alignment contains fragments between the leader peptide ORFs and the terminator hairpin followed by poly-U-tracts.