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

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. Overall design: 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).