Serendipitous discovery of an immunoglobulin-binding autotransporter in Bordetella species.
Serendipitous discovery of an immunoglobulin-binding autotransporter in Bordetella species.
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在博德特氏菌属中偶然发现了一种免疫球蛋白结合自转运蛋白。
DOI：
10.1128/iai.00323-08
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发表时间：
2008
影响因子：
3.1
通讯作者：
Cotter,PeggyA
中科院分区：
文献类型：
--
作者：
Williams,CorinneL;Haines,Robert;Cotter,PeggyA
We describe the serendipitous discovery of BatB, a classical-typeBordetellaautotransporter (AT) protein with an ∼180-kDa passenger domain that remains noncovalently associated with the outer membrane. Like genes encoding all characterized protein virulence factors inBordetellaspecies,batBtranscription is positively regulated by the master virulence regulatory system BvgAS. BatB is predicted to share similarity with immunoglobulin A (IgA) proteases, and we showed that BatB binds Ig in vitro. In vivo, aBordetella bronchisepticaΔbatBmutant was unable to overcome innate immune defenses and was cleared from the lower respiratory tracts of mice more rapidly than wild-typeB. bronchiseptica. This defect was abrogated in SCID mice, suggesting that BatB functions to resist clearance during the first week postinoculation in a manner dependent on B- and T-cell-mediated activities. Taken together with the previous demonstration that polymorphonuclear neutrophils (PMN) are critical for the control ofB. bronchisepticain mice, our data support the hypothesis that BatB prevents nonspecific antibodies from facilitating PMN-mediated clearance during the first few days postinoculation. Neither of the strictly human-adaptedBordetellasubspecies produces a fully functional BatB protein; nucleotide differences within the putative promoter region preventbatBtranscription inBordetella pertussis, and although expressed, thebatBgene of human-derivedBordetella parapertussis(B. parapertussishu) contains a large in-frame deletion relative tobatBofB. bronchiseptica. Taken together, our data suggest that BatB played an important role in the evolution of virulence and host specificity among the mammalian-adapted bordetellae.
