Identification of Burkholderia mallei and Burkholderia pseudomallei adhesins for human respiratory epithelial cells
Identification of Burkholderia mallei and Burkholderia pseudomallei adhesins for human respiratory epithelial cells
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DOI：
10.1186/1471-2180-10-250
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发表时间：
2010-09-28
期刊：
影响因子：
4.2
通讯作者：
Lafontaine, Eric R.
中科院分区：
文献类型：
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作者：
Balder, Rachel;Lipski, Serena;Lafontaine, Eric R.
背景：类鼻疽伯克霍尔德菌和鼻疽伯克霍尔德菌分别引起类鼻疽和鼻疽。这些密切相关的细菌的致病机制的一个充分研究的方面是它们在真核细胞内侵入和繁殖的能力。相反，B.类鼻疽和B.锤骨粘附细胞的界限不清。本研究的目的是确定这些organis.Results表达的粘附因子：比较序列分析确定了一个基因产物中公布的基因组B。鼻疽菌株ATCC 23344（基因座#BMAA 0649），其类似于充分表征的小肠结肠炎耶尔森氏菌自转运体粘附素YadA。编码这种B的基因。命名为boaA的鼻疽蛋白在大肠杆菌中表达，并显示出显著增加对人上皮细胞系，特别是HEp 2（喉细胞）和A549（II型肺细胞），以及对正常人支气管上皮（NHBE）培养物的粘附。与这些发现一致，在B.鼻疽ATCC 23344使对所有三种细胞类型的粘附降低了约50%。B的基因组。还发现类鼻疽菌株K96243和DD 503含有boaA，DD 503中基因的失活显著降低了与HEp 2和A549细胞单层以及NHBE培养物的结合。在已发表的B的基因组序列中鉴定出与BoaA高度相似的第二个YadA样基因产物（65%同一性）。类鼻疽菌株K96243（基因座#BPSL1705）。指定这种蛋白质的基因称为boa B，似乎是B。假鼻疽特异性。定量吸附实验表明，重组E.表达BoaB的大肠杆菌显示出与A549肺细胞、HEp 2细胞和NHBE培养物更强的结合。此外，还获得了B的boa B突变体。类鼻疽菌DD 503对这些呼吸细胞的粘附性降低。此外，一个B。pseudomallei菌株缺乏表达的boaA和boaB的能力受损的J774A.1小鼠巨噬细胞内茁壮成长，这表明这些蛋白质在专业吞噬细胞内的生存可能发挥的作用。结论：boaA和boaB基因指定粘附素介导的粘附到人呼吸道上皮细胞。boaA基因产物由B共享。类鼻疽和B.而Boa B似乎是一个B。假鼻疽特异性粘附因子。
Background: Burkholderia pseudomallei and Burkholderia mallei cause the diseases melioidosis and glanders, respectively. A well-studied aspect of pathogenesis by these closely-related bacteria is their ability to invade and multiply within eukaryotic cells. In contrast, the means by which B. pseudomallei and B. mallei adhere to cells are poorly defined. The purpose of this study was to identify adherence factors expressed by these organisms.Results: Comparative sequence analyses identified a gene product in the published genome of B. mallei strain ATCC23344 (locus # BMAA0649) that resembles the well-characterized Yersinia enterocolitica autotransporter adhesin YadA. The gene encoding this B. mallei protein, designated boaA, was expressed in Escherichia coli and shown to significantly increase adherence to human epithelial cell lines, specifically HEp2 (laryngeal cells) and A549 (type II pneumocytes), as well as to cultures of normal human bronchial epithelium (NHBE). Consistent with these findings, disruption of the boaA gene in B. mallei ATCC23344 reduced adherence to all three cell types by similar to 50%. The genomes of the B. pseudomallei strains K96243 and DD503 were also found to contain boaA and inactivation of the gene in DD503 considerably decreased binding to monolayers of HEp2 and A549 cells and to NHBE cultures. A second YadA-like gene product highly similar to BoaA (65% identity) was identified in the published genomic sequence of B. pseudomallei strain K96243 (locus # BPSL1705). The gene specifying this protein, termed boaB, appears to be B. pseudomallei-specific. Quantitative attachment assays demonstrated that recombinant E. coli expressing BoaB displayed greater binding to A549 pneumocytes, HEp2 cells and NHBE cultures. Moreover, a boaB mutant of B. pseudomallei DD503 showed decreased adherence to these respiratory cells. Additionally, a B. pseudomallei strain lacking expression of both boaA and boaB was impaired in its ability to thrive inside J774A.1 murine macrophages, suggesting a possible role for these proteins in survival within professional phagocytic cells.Conclusions: The boaA and boaB genes specify adhesins that mediate adherence to epithelial cells of the human respiratory tract. The boaA gene product is shared by B. pseudomallei and B. mallei whereas BoaB appears to be a B. pseudomallei-specific adherence factor.