Genome-Wide High-Throughput Screening to Investigate Essential Genes Involved in Methicillin-Resistant Staphylococcus aureus Sequence Type 398 Survival
Genome-Wide High-Throughput Screening to Investigate Essential Genes Involved in Methicillin-Resistant Staphylococcus aureus Sequence Type 398 Survival
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DOI：
10.1371/journal.pone.0089018
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发表时间：
2014-02-12
期刊：
影响因子：
3.7
通讯作者：
Aarestrup, Frank M.
中科院分区：
文献类型：
--
作者：
Christiansen, Mette T.;Kaas, Rolf S.;Aarestrup, Frank M.
家畜相关耐甲氧西林金黄色葡萄球菌（LA-MRSA）序列类型398（ST 398）是能够在包括人类在内的若干动物物种中定殖并引起疾病的机会病原体。为了更好地了解适应，进化，传播和致病能力，需要进一步调查LA-MRSA ST 398所携带的不同基因的重要性。在这项研究中，我们在LA-MRSA ST 398分离株中产生了一个全基因组转座子突变库，以评估在实验室和宿主特异性环境中对细菌存活重要的基因。转座子突变体文库由大约100万个突变体组成，具有大约140，000个独特插入位点，每个基因的独特插入物的平均数量为44.8。我们鉴定了LA-MRSA ST 398与其他高通量S.金黄色葡萄球菌必需基因研究。由于ST 398是从猪分离的最常见的MRSA，因此在全血中筛选转座子突变体文库。24个基因被特别鉴定为对猪血液中细菌存活重要。其中23个基因的突变导致细菌适应性减弱。23个基因中有7个基因的功能未知，而16个基因被注释的功能主要与碳代谢，pH休克和各种法规，只有间接的毒力因子。一个功能未知的基因突变导致了一个超竞争突变体。需要对这些基因进行进一步评估，以确定其在血液存活中的特定相关性。
Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) Sequence Type 398 (ST398) is an opportunistic pathogen that is able to colonize and cause disease in several animal species including humans. To better understand the adaptation, evolution, transmission and pathogenic capacity, further investigations into the importance of the different genes harboured by LA-MRSA ST398 are required. In this study we generated a genome-wide transposon mutant library in an LA-MRSA ST398 isolate to evaluate genes important for bacterial survival in laboratory and host-specific environments. The transposon mutant library consisted of approximately 1 million mutants with around 140,000 unique insertion sites and an average number of unique inserts per gene of 44.8. We identified LA-MRSA ST398 essential genes comparable to other high-throughput S. aureus essential gene studies. As ST398 is the most common MRSA isolated from pigs, the transposon mutant library was screened in whole porcine blood. Twenty-four genes were specifically identified as important for bacterial survival in porcine blood. Mutations in 23 of these genes resulted in attenuated bacterial fitness. Seven of the 23 genes were of unknown function, whereas 16 genes were annotated with functions predominantly related to carbon metabolism, pH shock and a variety of regulations and only indirectly to virulence factors. Mutations in one gene of unknown function resulted in a hypercompetitive mutant. Further evaluation of these genes is required to determine their specific relevance in blood survival.