Adult bovine serum (10%) alters the expression of Pseudomonas aeruginosa genes

ABSTRACT: As production of virulence factors by Pseudomonas aeruginosa is influenced by the host environment, we examined the effect of 10% adult bovine serum (ABS) on the global transcription with P. aeruginoas PAO1 at different phases of growth. At early exponential phase (4 h), serum significantly enhanced expression of 138 genes, most of which are repressed by iron and carry binding sequences for the ferric uptake regulator or the Fur-regulated extracytoplasmic function sigma factor PvdS. The expression of another 40 genes was reduced at 4h. However, the expression of only a few genes was significantly altered (reduced) at the early stationary phase of growth (8 h). Transcriptional fusion analyses confirmed serum enhances the expression of toxA, regA, and their regulatory genes regA and pvdS, yet does not interfere with the repression of these genes by iron. The P. aeruginosa strain PAO1 was grown in the iron-limited medium TSB-DC with or without 10% (v/v) ABS. The presence of 10% ABS reduced PAO1 growth, but despite this reduction, the cultures reached early exponential phase at 4 h and early stationary phase at 8 h in both media. Accordingly, we determined the PAO1 transcriptome in both media at these two specific time points. To standardize the comprison, we adjusted the cultures to the same optical density at 600 nm (biomass) by diluting with fresh TSB-DC PAO1 grown in TSB-DC to the same OD as PAO1 grown in TSB-DC/ABS. We obtained the transcriptome profile of 5,552 genes representing the complete P. aeruginosa PAO1 genome.

ORGANISM(S): Pseudomonas aeruginosa

SUBMITTER: Jane Colmer-Hamood 

PROVIDER: E-GEOD-30698 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress