Figure 1.

Schematic representation of the genomic organization of the genes present in the five ESAT-6 gene cluster regions of Mycobacterium tuberculosis H37Rv as well as the regions in C. diphtheriae and S. coelicolor. ORFs are represented as blocked arrows showing the direction of transcription, with the different colors reflecting the specific gene family and the length of the arrow reflecting the relative lengths of the genes. Annotations of M. tuberculosis H37Rv genes are according to Cole et al. [13]. Black arrows indicate unconserved genes present in these regions. Gaps between genes do not represent physical gaps between genes on the genome, but have been inserted to aid in indicating conservation among gene positions. Gene families were named arbitrarily according to their position in M. tuberculosis H37Rv region 1. The regions were named after the numbering system of Brown et al. [19] used arbitrarily for the five mycosin (subtilisin-like serine protease) genes identified from these regions (family K). M. tuberculosis regions are shown in order of suggested duplication events (see phylogenetic results) and not by numbering. The results of the analyses of the primary features of these genes and their corresponding proteins are included in a short summary at the bottom of the figure (see also Table 2).