Fluctuations in phenotypes and genotypes within populations of Pseudomonas aeruginosa in the cystic fibrosis lung during pulmonary exacerbations
Fluctuations in phenotypes and genotypes within populations of Pseudomonas aeruginosa in the cystic fibrosis lung during pulmonary exacerbations
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DOI：
10.1099/jmm.0.015875-0
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发表时间：
2010-04-01
影响因子：
3
通讯作者：
Winstanley, Craig
中科院分区：
文献类型：
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作者：
Fothergill, Joanne L.;Mowat, Eilidh;Winstanley, Craig
铜绿假单胞菌引起的慢性呼吸道感染是囊性纤维化（CF）相关发病率和死亡率的重要原因。使用一系列的表型和基因型测试收集40个分离株/痰液样本，我们分析了铜绿假单胞菌利物浦流行株（LES）的痰液种群内的波动，在肺部急性加重。对于三名患者中的每一名，分析了三个连续的痰样本：（1）在利物浦地区成人囊性纤维化单位出现恶化时;（2）静脉内抗生素治疗几天后;（3）患者恢复时。在形态分布、与毒性相关的群体感应依赖性外产物（吩嗪化合物绿脓菌素和弹性蛋白酶LasA）的产生、抗生素敏感性概况和营养缺陷型水平方面观察到波动。PCR检测用于筛选LES基因组新区域（岛和原噬菌体）的存在的分离株，并检测游离β-内酰胺酶。在一名患者中，在采样期间，LESGI-5基因组岛的患病率从10%增加到97.5%。在大多数或所有测试的痰样品中检测到LES E2 -4，表明在采样期间广泛的噬菌体活性。本研究的结果表明，铜绿假单胞菌种群在短期肺恶化和静脉抗生素治疗期间发生显著波动。
Chronic respiratory infection by Pseudomonas aeruginosa contributes significantly to the morbidity and mortality associated with cystic fibrosis (CF). Using a series of phenotypic and genotypic tests on collections of 40 isolates per sputum sample, we analysed fluctuations within sputum populations of the P. aeruginosa Liverpool epidemic strain (LES) during pulmonary exacerbations. For each of three patients, three sequential sputum samples were analysed: (1) on presentation with exacerbation at the Regional Adult Cystic Fibrosis Unit, Liverpool; (2) a few days into intravenous antibiotic treatment; (3) when the patient had recovered. Fluctuations were observed in morphotype distribution, the production of virulence-associated quorum-sensing-dependent exoproducts (the phenazine compound pyocyanin and the elastase LasA), antibiotic susceptibility profiles and levels of auxotrophy. PCR assays were used to screen isolates for the presence of novel regions of the LES genome (islands and prophages) and to detect free phages. In one patient there was an increase in the prevalence of the LESGI-5 genomic island during the sampling period from 10 to 97.5% carriage. LES phages 2-4 were detected in either the majority or all sputum samples tested, indicating widespread phage activity during the sampling period. The results of this study are indicative that significant fluctuations occur within P. aeruginosa populations during short periods of pulmonary exacerbation and intravenous antibiotic therapy.