Transcriptomic comparison of serotype M1 S. pyogenes

S. pyogenes strains were compared with the intact covRS form of the globally disseminated M1T1 clone to track transcriptomic changes engendered during the emergence of the M1T1 clone. The mutant covRS form of the M1T1 clone was included as a transcriptomic outlier and to provide a context for the magnitude of transcriptional shifts detected within the isolate set examined. Microarray was performed on RNA extracted from mid-logarithmic phase S. pyogenes grown in Todd-Hewitt with 1% yeast extract in vitro. Experiments were performed using a single color method. Each sample was labelled with Cy3 and hybridized to separate arrays. Each strain was analysed in 3 biological replicates. cDNA hybridized to JCVI PFGRC Streptococcus pyogenes v2 oligo arrays. Only probed representing the core M1 genome were used for analysis.