Update publication information. Natural transformation, as one of the horizontal gene transfer (HGT) modes of bacteria, allows bacteria to actively uptake foreign DNA under natural conditions and integrate it into their genome through homologous recombination. Natural transformation plays an vital role in the rapid spread of pathogen virulence factors and resistance genes, resulting in the emergence of multidrug resistant or highly pathogenic strains.To investigate the mechanism by which tfoX regulates the natural transformation process of Glaesserella parasuis, comparative proteomics studies were performed on the parent wild strain SC1401 and the tfoX deficient strain.