A general protein O-glycosylation system within the Burkholderia cepacia complex is involved in motility and virulence
A general protein O-glycosylation system within the Burkholderia cepacia complex is involved in motility and virulence
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DOI：
10.1111/mmi.12540
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发表时间：
2014-04-01
影响因子：
3.6
通讯作者：
Dennis, Jonathan J.
中科院分区：
文献类型：
--
作者：
Lithgow, Karen V.;Scott, Nichollas E.;Dennis, Jonathan J.
洋葱伯克霍尔德氏菌复合体（Bcc）的细菌是人类、植物和动物的病原体。新洋葱伯克霍尔德菌是囊性纤维化（CF）患者最常见的Bcc菌之一，其携带与预后不良相关。在这项研究中，我们的特点是一个一般的O-连接的蛋白质糖基化系统在B.cenocepaciaK56-2。由克隆的基因bcal 0960编码的PglL（Bc）O-寡糖基转移酶（O-OTase）被证明能够在大肠杆菌背景中将七糖从空肠弯曲杆菌N-糖基化系统转移到脑膜炎奈瑟氏菌衍生的受体蛋白，表明该酶对糖供体和蛋白受体都具有松弛的特异性。在BcenocepaciaK 56 -2中，PglL（Bc）负责参与不同细胞过程的23种蛋白质的糖基化。质谱分析显示，这些蛋白质被三糖HexNAc-HexNAc-Hex修饰，这与O-抗原生物合成过程无关。所鉴定的糖基化位点存在于低复杂性区域内，富含丝氨酸、丙氨酸和脯氨酸。破坏bcal 0960废除糖基化，并导致游泳运动性降低，对植物和昆虫模式生物的毒力减弱。这项研究证明了第一个翻译后修饰的BCC与发病机制的影响。
Bacteria of the Burkholderia cepacia complex (Bcc) are pathogens of humans, plants, and animals. Burkholderia cenocepacia is one of the most common Bcc species infecting cystic fibrosis (CF) patients and its carriage is associated with poor prognosis. In this study, we characterized a general O-linked protein glycosylation system in B.cenocepaciaK56-2. The PglL(Bc)O-oligosaccharyltransferase (O-OTase), encoded by the cloned gene bcal0960, was shown to be capable of transferring a heptasaccharide from the Campylobacter jejuniN-glycosylation system to a Neisseria meningitides-derived acceptor protein in an Escherichia coli background, indicating that the enzyme has relaxed specificities for both the sugar donor and protein acceptor. In BcenocepaciaK56-2, PglL(Bc) is responsible for the glycosylation of 23 proteins involved in diverse cellular processes. Mass spectrometry analysis revealed that these proteins are modified with a trisaccharide HexNAc-HexNAc-Hex, which is unrelated to the O-antigen biosynthetic process. The glycosylation sites that were identified existed within regions of low complexity, rich in serine, alanine, and proline. Disruption of bcal0960 abolished glycosylation and resulted in reduced swimming motility and attenuated virulence towards both plant and insect model organisms. This study demonstrates the first example of post-translational modification in Bcc with implications for pathogenesis.