Fig. 1.

Chlamydial HrcA contains an additional C-terminal tail. Alignment of the C-terminal sequence of HrcA from six Chlamydia spp. (C. trachomatis, C. muridarum, C. abortus, C. felis, C. caviae, and C. pneumoniae), the related organism Protochlamydia amoebophila, and selected bacteria in which HrcA has been previously studied and/or identified. The amino acid sequence was inferred from each nucleotide sequence and analyzed with ClustalW software at http://www.ebi.ac.uk/Tools/clustalw2/index.html. Amino acid residues in the C terminus that are identical, strongly similar, or weakly similar among all HrcA orthologs are marked by an asterisk, colon, or period, respectively. The total number of amino acids (aa) in each HrcA ortholog is listed. The tandem arginine residues of C. trachomatis HrcA implicated in the premature termination of translation in E. coli are bolded and underlined.