微生物变异问题在历史上曾经是许久以来悬而未决的问题。这个问题在十九世纪曾引起很大的争论,唯心论和机械唯物论的学者主张微生物是不会变的,认为偶然发现的变异菌种只是污染的杂菌或细菌的衰残型,或是不相干的新菌种;菌落变异和其相关的生物化学性质、毒性、抗原性等的变异不过是同一菌种内所发生的相当性质 The issue of microbial variation has historically been a pending issue for a long time. This issue has caused considerable controversy in the nineteenth century. The scholars of idealism and mechanical materialism argue that the microorganisms will not change. It is believed that the mutant species discovered by accident is only the decaying bacteria or bacteria that are contaminated, or Irrespective of the new species; the variation of the colony and its associated biochemical properties, toxicity, antigenicity, etc. are but rather equivalent properties that occur within the same species