Gene expression-based analysis of Streptococcus uberis 0140J and the MtuR (sub0472) mutant

Comparison of bacterial strain S. uberis 0140J with an isogenic mutant (same strain) with a lesion 338 basepairs downstream of the ATG start codon of the MtuR or sub0472 gene. Bacteria were grown in stationary culture in THB media at 37°C in the presence of 1mM manganese with triplicate samples of RNA extracted at early exponential (OD550 =0.43) and late exponential (OD550 =0.78) phases of growth. Microarray analysis was performed on custom-made S. uberis 0140J arrays containing 3780 features of 60mer oligonucleotides in triplicate with two probes for each individual gene. We investigated the role of MtuR in vivo and the effect of its absence on the transcriptional control of gene expression using a custom-designed genome-wide S. uberis 0140J microarray containing 3780 features in triplicate with two probes for each individual gene. Triplicate samples were analysed in a loop design with Cy5 and Cy3 dye-swaps performed, and gene expression was compared at two different phases of bacterial growth (early and late logarithmic).