has role virmugen virmugen role Actinobacillus pleuropneumoniae gene apxIIIB from Actinobacillus pleuropneumoniae gene Rebecca Racz An apxIIIB mutant, in combination with an apxIIID mutation, is highly attenuated in pigs and induces significant protection from challenge with wild type A. pleuropneumoniae. The mutant also was slightly attenuated in mice and induced protection in mice against challenge from the parent strain NCBI_Nucleotide_ID: 470686; PMID: 19887737 Oliver He