Expression data of Actinobacillus pleuropneumoniae 4074 in response to serum, epinephrine, norepinephrine and dopamine

Bacteria can actively respond to host stress hormones (catecholamines), thereby regulate their growth, metabolism, virulence and other behaviors. This phenomenon provides new explanations of the fact that stress can influence the occurrence and development of infectious disease. Actinobacillus pleuropneumoniae is an important swine respiratory pathogen which has caused great economic losses worldwide. In our previous study, it has been discovered that catecholamines can regulate the expression of a great number of genes of A. pleuropneumoniae. In this study, the effect of catecholamines on A. pleuropneumoniae growth was detected using chemically defined medium (CDM). The results showed that in CDM, serum inhibited A. pleuropneumoniae growth, while epinephrine (Epi), norepinephrine (NE) and dopamine (DA) promoted A. pleuropneumoniae growth in the CDM containing serum. The known bacterial adrenergic receptor QseC didn’t play role in this process. According to growth features after supplementation of ions and genes expression changes caused by serum, Epi, NE and DA, it was discovered that serum established iron-restricted conditions for A. pleuropneumoniae and catecholamines removed the restrictions of iron. Apo-transferrin but not holo-transferrin also inhibited the growth of A. pleuropneumoniae in CDM. Catecholamines induced growth of A. pleuropneumoniae in the CDM containing apo-transferrin. Hence transferrin was one of the components in the serum that caused growth inhibition and was used by catecholamines to facilitate growth. In addition, TonB2 of A. pleuropneumoniae played essential roles in this process. The investigations in this study indicated that catecholamines promoted A. pleuropneumoniae growth by regulating iron acquisition and metabolism, which could be important during pathogenic processes. Five condition experiment, 4074 cultured in chemically defined medium (CDM) as control, in CDM+serum, in CDM+serum+epinephrine, in CDM+serum+norepinephrine, in CDM+serum+dopamine, respectively. Each condition has three biological replicates. Bacteria were harvested at mid-log phase and total RNA were extracted.