Staphylococcal enterotoxin-like X (SElX) is a unique superantigen with functional features of two major families of staphylococcal virulence factors
Fig 9
(A) Alignment of the region upstream from selX with the known upstream regulatory regions of ssl1, ssl7, ssl9, and ssl11. The -10 and -35 promoter elements are boxed and the region of homology to the saeR binding site (GTTAA-n6-GTTAA) is highlighted in grey. Conserved residues are indicated with an asterisk. (B). Relative selX transcript levels in S. aureus isolated from abscesses (n = 6) removed at 24 hr, 48 hr, or 96 hr after subcutaneous infection of mice with 5x106 S. aureus Newman or JSNZ. selx, saeR expression normalized to reference genes gyrB and ftsZ and compared to in vitro expression of the inoculum. Each data point is the mean of triplicate values from an individual abscess, with the median of these mean values shown. Statistics were performed using Graphpad Prism. Kruskal—Wallis one way ANOVA was performed and comparisons between the in vivo samples and the inoculum were made using Dunn's Multiple Comparison Test. The p value of significantly different groups is shown.