Expression of the lipopolysaccharide biosynthesis gene lpxD affects biofilm formation of Pseudomonas aeruginosa
Expression of the lipopolysaccharide biosynthesis gene lpxD affects biofilm formation of Pseudomonas aeruginosa
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DOI：
10.1007/s00203-014-1030-y
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发表时间：
2015-03-01
影响因子：
2.8
通讯作者：
Anderson, Gregory G.
中科院分区：
文献类型：
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作者：
Alshalchi, Sahar A.;Anderson, Gregory G.
细菌生物膜是引起医院感染的重要原因。微生物如铜绿假单胞菌定殖于生物和非生物表面，导致难以根除的慢性感染。为了表征参与生物膜形成的新基因，我们从铜绿假单胞菌的转座子突变库中鉴定了lpxD基因。该基因编码葡糖胺-N酰基转移酶，其对于脂多糖生物合成是重要的。我们的研究结果表明，lpxD的表达缺失突变体是有缺陷的生物和非生物表面上的生物膜形成。此外，该突变菌株表现出显著降低的细菌对培养的气道上皮细胞的附着，以及增加的细菌对气道细胞的细胞毒性。然而，与脂质A结构缺陷一致，与lpxD突变体或突变体脂质A提取物孵育的气道细胞分别表现出IL-8产生减少和坏死。总之，我们的数据表明，操纵lpxD表达可能会影响铜绿假单胞菌建立生物膜感染的能力。
Bacterial biofilms are an important cause of nosocomial infections. Microorganisms such as Pseudomonas aeruginosa colonize biotic and abiotic surfaces leading to chronic infections that are difficult to eradicate. To characterize novel genes involved in biofilm formation, we identified the lpxD gene from a transposon-mutant library of P. aeruginosa. This gene encodes a glucosamine-N acyltransferase, which is important for lipopolysaccharide biosynthesis. Our results showed that a loss-of-expression mutant of lpxD was defective for biofilm formation on biotic and abiotic surfaces. Additionally, this mutant strain exhibited significantly decreased bacterial attachment to cultured airway epithelial cells, as well as increased bacterial cytotoxicity toward airway cells. However, consistent with a defect in lipid A structure, airway cells incubated with the lpxD mutant or with mutant lipid A extracts exhibited decreased IL-8 production and necrosis, respectively. Overall, our data indicate that manipulating lpxD expression may influence P. aeruginosa's ability to establish biofilm infections.