are pathogenic bacteria antigenic
Many pathogenic bacteria exist in nature as multiple antigenic types or serotypes, meaning that they are variant strains of the same pathogenic species. For example, there are multiple serotypes of Salmonella typhimurium based on differences in cell wall (O) antigens or flagellar (H) antigens.any pathogenic bacteria exist in nature as multiple antigenic types or serotypes, meaning that they are variant strains of the same pathogenic species. For example, there are multiple serotypes of Salmonella typhimurium based on differences in cell wall (O) antigens or flagellar (H) antigens.