title: Catecholamines promote Actinobacillus pleuropneumoniae growth by regulating iron metabolism.
abstract: Catecholamines are host stress hormones that can induce the growth of many bacteria by facilitating iron utilization and/or regulate the expression of virulence genes through specific hormone receptors. Whether these two responsive pathways are interconnected is unknown. In our previous study, it was found that catecholamines can regulate the expression of a great number of genes of Actinobacillus pleuropneumoniae, an important swine respiratory pathogen. However, bacterial growth was not affected by catecholamines in rich medium. In this study, it was discovered that catecholamines affected A. pleuropneumoniae growth in chemically defined medium (CDM). We found that serum inhibited A. pleuropneumoniae growth in CDM, while epinephrine, norepinephrine and dopamine promoted A. pleuropneumoniae growth in the CDM containing serum. The known bacterial hormone receptor QseC didn't play roles in this process. Ion-supplementation and transcriptome analysis indicated that serum addition resulted in iron-restricted conditions which were alleviated by the addition of catecholamines. Transferrin, one of the components in serum, inhibited the growth of A. pleuropneumoniae in CDM, an effect reversed by addition of catecholamines in a TonB2-dependent manner. Our data demonstrate that catecholamines promote A. pleuropneumoniae growth by regulating iron-acquisition and metabolism, which is independent of the adrenergic receptor QseC.
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Lu
authors: L
authors: Li
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Zhaohui
authors: Z
authors: Chen
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Weicheng
authors: W
authors: Bei
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Zhipeng
authors: Z
authors: Su
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Qi
authors: Q
authors: Huang
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Liang
authors: L
authors: Zhang
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Huanchun
authors: H
authors: Chen
authors: State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
authors: Rui
authors: R
authors: Zhou
mesh_terms: D016977:Actinobacillus pleuropneumoniae / Q000254:growth & development*; D001426:Bacterial Proteins / Q000096:biosynthesis*; D002395:Catecholamines / Q000378:metabolism / Q000494:pharmacology*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects* / Q000502:physiology; D007501:Iron / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D002395:Catecholamines; D007501:Iron