Pyridoxal phosphate synthases PdxS/PdxT are required for Actinobacillus pleuropneumoniae viability, stress tolerance and virulence

PLoS One

Yalei Wang¹  Yanhe Zhang²  Shuanghong Liu²  Siguo Liu²  Fang Xie²  Gang Li²  Long Zhou²  Chengcheng Wang²  Chunlai Wang² 

[1] Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, People’s Republic of China;State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China

关键词: Biosynthesis;    Mutant strains;    Glutamine;    Polymerase chain reaction;    Mouse models;    Oxidative stress;    Osmotic shock;    Plasmid construction;   

DOI  :  10.1371/journal.pone.0176374

学科分类：医学（综合）

来源: Public Library of Science

【 摘 要 】

Pyridoxal 5’-phosphate (PLP) is an essential cofactor for numerous enzymes involved in a diversity of cellular processes in living organisms. Previous analysis of the Actinobacillus pleuropneumoniae S-8 genome sequence revealed the presence of pdxS and pdxT genes, which are implicated in deoxyxylulose 5-phosphate (DXP)-independent pathway of PLP biosynthesis; however, little is known about their roles in A. pleuropneumoniae pathogenicity. Our data demonstrated that A. pleuropneumoniae could synthesize PLP by PdxS and PdxT enzymes. Disruption of the pdxS and pdxT genes rendered the pathogen auxotrophic for PLP, and the defective growth as a result of these mutants was chemically compensated by the addition of PLP, suggesting the importance of PLP production for A. pleuropneumoniae growth and viability. Additionally, the pdxS and pdxT deletion mutants displayed morphological defects as indicated by irregular and aberrant shapes in the absence of PLP. The reduced growth of the pdxS and pdxT deletion mutants under osmotic and oxidative stress conditions suggests that the PLP synthases PdxS/PdxT are associated with the stress tolerance of A. pleuropneumoniae. Furthermore, disruption of the PLP biosynthesis pathway led to reduced colonization and attenuated virulence of A. pleuropneumoniae in the BALB/c mouse model. The data presented in this study reveal the critical role of PLP synthases PdxS/PdxT in viability, stress tolerance, and virulence of A. pleuropneumoniae.

【 授权许可】

CC BY