Identification and characterization of an Acinetobacter baumannii biofilm-associated protein
Identification and characterization of an Acinetobacter baumannii biofilm-associated protein
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DOI：
10.1128/jb.01416-07
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发表时间：
2008-02-01
影响因子：
3.2
通讯作者：
Campagnari, Anthony A.
中科院分区：
文献类型：
--
作者：
Loehfelm, Thomas W.;Luke, Nicole R.;Campagnari, Anthony A.
我们已经确定了同源的葡萄球菌生物膜相关蛋白（Bap）的血液分离鲍曼不动杆菌。完全测序的开放阅读框为25，863 bp，编码预测分子量为854 kDa的蛋白质。核苷酸序列的分析揭示了与细菌细胞表面粘附素一致的重复结构。Bap特异性单克隆抗体6E3针对A.最近在美国军事卫生保健系统爆发期间分离的鲍曼不动杆菌菌株。流式细胞术证实MAb 6E3表位表面暴露。采用随机转座子诱变技术获得A.鲍曼不动杆菌bap1302：：EZ-Tn5，一种对MAb 6E3表面反应性阴性的突变体，其中转座子破坏了bap的编码序列。时程共聚焦激光扫描显微镜和三维图像分析的积极增长的生物膜表明，这种突变体是无法维持生物膜的厚度和体积，这表明Bap在支持成熟的生物膜结构的发展的作用。这是首次鉴定出直接参与A.提示Bap参与成熟生物膜内的细胞间粘附。
We have identified a homologue to the staphylococcal biofilm-associated protein (Bap) in a bloodstream isolate of Acinetobacter baumannii. The fully sequenced open reading frame is 25,863 bp and encodes a protein with a predicted molecular mass of 854 kDa. Analysis of the nucleotide sequence reveals a repetitive structure consistent with bacterial cell surface adhesins. Bap-specific monoclonal antibody (MAb) 6E3 was generated to an epitope conserved among 41% of A. baumannii strains isolated during a recent outbreak in the U.S. military health care system. Flow cytometry confirms that the MAb 6E3 epitope is surface exposed. Random transposon mutagenesis was used to generate A. baumannii bap1302::EZ-Tn5, a mutant negative for surface reactivity to MAb 6E3 in which the transposon disrupts the coding sequence of bap. Time course confocal laser scanning microscopy and three-dimensional image analysis of actively growing biofilms demonstrates that this mutant is unable to sustain biofilm thickness and volume, suggesting a role for Bap in supporting the development of the mature biofilm structure. This is the first identification of a specific cell surface protein directly involved in biofilm formation by A. baumannii and suggests that Bap is involved in intercellular adhesion within the mature biofilm.