The single ECF sigma factor of Xylella fastidiosa is involved in the heat shock response

Genome sequence analysis of the bacterium Xylella fastidiosa revealed the presence of two genes, named rpoE and rseA, predicted to encode an ECF sigma factor and an anti-sigma factor, respectively. In this work, an rpoE null mutant was constructed in the citrus strain J1a12 and shown to be sensitive to exposure to heat shock and ethanol. To identify the X. fastidiosa σE regulon, global gene expression profiles were obtained by DNA microarray analysis of bacterial cells under heat shock identifying 23 sigmaE-dependent genes. Keywords: stress response, heat shock, rpoE mutant strain Direct comparison between wild type strain J1a12 and mutant strain rpoE- at normal temperatures and at heat shock (40oC, 25min). There are at least 3 biological replicates (independent harvest) and 2 technical replicates of each array (L - left and R - right).