Abstract:
Bacteria can repurpose their own bacteriophage viruses (phage) to kill competing bacteria. Phage-derived elements are frequently strain specific in their killing activity, although there is limited evidence that this specificity drives bacterial population dynamics. Here, we identified intact phage and their derived elements in a metapopulation of wild plant-associated Pseudomonas genomes. We discovered that the most abundant viral cluster encodes a phage remnant resembling a phage tail called a tailocin, which bacteria have co-opted to kill bacterial competitors. Each pathogenic Pseudomonas strain carries one of a few distinct tailocin variants that target the variable polysaccharides in the outer membrane of co-occurring pathogenic Pseudomonas strains. Analysis of herbarium samples from the past 170 years revealed that the same tailocin and bacterial receptor variants have persisted in Pseudomonas populations. These results suggest that tailocin genetic diversity can be mined to develop targeted \"tailocin cocktails\" for microbial control.
摘要:
细菌可以重新利用自己的噬菌体病毒(噬菌体)来杀死竞争细菌。噬菌体衍生的元素通常在它们的杀伤活动中具有特异性,尽管有限的证据表明这种特异性驱动细菌种群动态。这里,我们在与野生植物相关的假单胞菌基因组的种群中鉴定了完整的噬菌体及其衍生元件。我们发现最丰富的病毒簇编码类似于噬菌体尾巴的噬菌体残留物,称为尾素,哪些细菌选择杀死细菌竞争者。每种致病性假单胞菌菌株都带有几种不同的尾素变体之一,这些变体靶向共同发生的致病性假单胞菌菌株的外膜中的可变多糖。对过去170年的植物标本室样品的分析表明,假单胞菌种群中仍然存在相同的尾素和细菌受体变体。这些结果表明,可以挖掘尾纤素的遗传多样性,以开发针对微生物控制的“尾纤素鸡尾酒”。