Speciation despite globally overlapping distributions in Penicillium chrysogenum: the population genetics of Alexander Fleming's lucky fungus

Eighty years ago, Alexander Fleming described the antibiotic effects of a fungus that had contaminated his bacterial culture, kick starting the antimicrobial revolution. The fungus was later ascribed to a putatively globally distributed asexual species, Penicillium chrysogenum. Recently, the species has been shown to be genetically diverse, and possess mating-type genes. Here, phylogenetic and population genetic analyses show that this apparently ubiquitous fungus is actually composed of at least two genetically distinct species with only slight differences detected in physiology. We found each species in air and dust samples collected in and around St Mary’s Hospital where Fleming worked. Genotyping of 30 markers across the genome showed that preserved fungal material from Fleming’s laboratory was nearly identical to derived strains currently in culture collections and in the same distinct species as a wild progenitor strain of current penicillin producing industrial strains rather tha...八十余年前，亚历山大·弗莱明（Alexander Fleming）报道了一株污染其细菌培养物的真菌所具备的抗菌活性，由此开启了抗菌革命的序幕。该真菌后续被归为一种推测为全球分布的无性物种——产黄青霉（Penicillium chrysogenum）。近期研究表明，该物种存在遗传多样性，且携带有交配型基因。本研究通过系统发育与群体遗传分析发现，这一此前被认为广泛分布的真菌实则包含至少两个遗传分化显著的物种，二者仅在生理特征上存在细微差异。我们在弗莱明曾工作过的圣玛丽医院（St Mary’s Hospital）内外采集的空气与尘埃样本中，均分离得到了这两个物种。对全基因组30个遗传标记的基因分型结果显示，弗莱明实验室留存的真菌菌株与目前保藏于菌种保藏中心的衍生菌株几乎完全一致，且与当前工业青霉素生产菌株的野生祖先菌株同属一个独特物种，而非……