I'd like to clarify that Ssc2 is CT576 and Ssc3 is CT862 - as outlined in the gene map of Fig 2 and not as described in the Discussion section and throughout the rest of the text.

I'd like to thank Jejun Wang at the Bioinformatics Group of the Plant Metabolic Engineering & Systems Biology Laboratory
Department of Biology, CUHK for pointing out the typo in the discussion section and I apologize for any confusion it may have caused.

The issue of the annotation of CT274 as a T3S chaperone was also raised. Such similarities where brought up first by Ken Fields on a review chapter "The Chlamydia Type III secretion System" in the book "Chlamydia: Genomics & Pathogenesis" edited by Bavoil and Wyrick, as a small acidic protein with amphiphatic alpha helices and TPR repeats. More recently, "The chlamydial type III secretion mechanism: revealing cracks in a tough nut" in Frontiers in Microbiology also covers this putative T3S chaperone and Chlamydia T3S in general. They also state that it has similarity to SycD. Indeed, PSI-BAST searches picked some weak similarities. Other folks have noted similarities between CT274 and T3S chaperones, including JF Kim (Trends in Genetics 2001) and RS Ghupta (BMC Genomics 2006).