Coevolution of antibiotic production and counter-resistance in soil bacteria
Coevolution of antibiotic production and counter-resistance in soil bacteria
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DOI：
10.1111/j.1462-2920.2009.02125.x
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发表时间：
2010-03-01
影响因子：
5.1
通讯作者：
Wellington, Liz
中科院分区：
文献类型：
--
作者：
Laskaris, Paris;Tolba, Sahar;Wellington, Liz
P>；我们提出了土壤细菌中抗生素耐药性基因和生物合成基因共存和共同进化的证据。检测链霉菌对链霉素(StrA)和万古霉素(VPh)耐药基因的分布。StrA和VPh存在于生物合成基因簇中或独立存在。具有链霉素簇的灰色链霉菌菌株形成了克隆复合体的一部分。所有只具有StrA的灰链霉菌都属于两个分支，都与链霉素产生菌有密切的关系。其他亲缘关系较远的灰链霉菌株不含StrA。只含有VPH的稻瘟病菌菌株也形成了两个分支，但它们与生产者和彼此之间的亲缘关系更远。StrA基因在纯抗性菌株中的表达是结构性的，而链霉素产生菌的StrA表达在对数后期达到峰值，这与链霉素生物合成的开启有关。虽然有证据表明抗生素在自然界中有不同的作用，但我们的数据显然支持在密切相关的土壤细菌中存在抗生素生物合成能力的情况下耐药性的共同进化。这强化了这样一种观点，即，至少对某些抗生素来说，在土壤中争夺资源的过程中，抗生素的主要作用之一。
P>We present evidence for the coexistence and coevolution of antibiotic resistance and biosynthesis genes in soil bacteria. The distribution of the streptomycin (strA) and viomycin (vph) resistance genes was examined in Streptomyces isolates. strA and vph were found either within a biosynthetic gene cluster or independently. Streptomyces griseus strains possessing the streptomycin cluster formed part of a clonal complex. All S. griseus strains possessing solely strA belonged to two clades; both were closely related to the streptomycin producers. Other more distantly related S. griseus strains did not contain strA. S. griseus strains with only vph also formed two clades, but they were more distantly related to the producers and to one another. The expression of the strA gene was constitutive in a resistance-only strain whereas streptomycin producers showed peak strA expression in late log phase that correlates with the switch on of streptomycin biosynthesis. While there is evidence that antibiotics have diverse roles in nature, our data clearly support the coevolution of resistance in the presence of antibiotic biosynthetic capability within closely related soil dwelling bacteria. This reinforces the view that, for some antibiotics at least, the primary role is one of antibiosis during competition in soil for resources.