Effects of OxyR regulator on oxidative stress, Apx toxin secretion and virulence of Actinobacillus pleuropneumoniae

• DOI: 10.3389/fcimb.2023.1324760
• Publication Date: 2024-01-10T04:50:37Z
• Authors: Fangfang Guo; Rong Quan; Yifang Cui; Xiaoya Cao; Tong Wen; Fuzhou Xu
• Keywords: Actinobacillus pleuropneumoniae; Virulence factor

Introduction Actinobacillus pleuropneumoniae , the causative agent of porcine pleuropneumonia, poses a significant threat to global swine populations due its high prevalence, mortality rates, and substantial economic ramifications. Understanding pathogen's defense mechanisms against host-produced reactive oxygen species is crucial for survival, with OxyR, conserved bacterial transcription factor, being pivotal in oxidative stress response. Methods This study investigated presence role OxyR A. serovar 1-12 reference strains. Transcriptomic analysis was conducted on an oxyR disruption mutant delineate biological activities influenced by OxyR. Additionally, specific assays were employed assess urease activity, catalase expression, ApxI toxin secretion, as well adhesion invasion abilities 3D4/21 PT cells. A mice challenge experiment also evaluate impact inactivation virulence. Results identified regulator present revealed involvement multiple activities. The resulted decreased elevated enhanced secretion—attributed binding apxIBD promoter—and reduced Furthermore, virulence experiment. Discussion findings highlight influencing . observed effects various underscore essential factor contributing pathogenicity this bacterium.