Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, PR China.
Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou, PR China.
J Proteomics. 2019 Mar 20;195:66-75. doi: 10.1016/j.jprot.2019.01.008. Epub 2019 Jan 17.
Brucella rough mutants are reported to induce infected macrophage death, which is type IV secretion system (T4SS) dependent. T4SS and its secretory proteins play a major role in host-bacteria interactions, but the crucial secretory proteins to promote macrophage death during Brucella rough mutant infection have not been characterized. In this study, we found that T4SS components played no role for macrophage death induced by Brucella rough mutant infection, but some T4SS effectors did. Proteomics of secretory proteins from Brucella rough mutants ΔrfbE and ΔrfbEΔvirB123 was analyzed by liquid chromatography/tandem mass spectrometry and 861 unique proteins were identified, among which 37 were differential secretory proteins. Gene ontology and pathway analysis showed that differential secretory proteins involved in cellular process and metabolic process, distributed in the cell and membrane, possessed molecular function of catalytic activity and binding, and were associated with ribosome, NOD-like receptor signaling pathway, two-component system and bacterial secretion system. Cell death analysis showed that T4SS effector VceC, and two differential secretory proteins OmpW family protein (BAB1_1579) and protein BAB1_1185 were associated with Brucella cytotoxicity. This study provides new insights into the molecular mechanisms associated with Brucella cytotoxicity and valuable information for screening vaccine candidates for Brucella. SIGNIFICANCE: Brucella rough mutants induce infected macrophage death, which is T4SS dependent. In the present report, a comparative proteomics analysis revealed 37 differential secretory proteins between Brucella rough mutants ΔrfbE and ΔrfbEΔvirB123. Further study demonstrated OmpW family protein (BAB1_1579) and uncharacterized protein BAB1_1185, two differential secretory proteins, were associated with Brucella cytotoxicity. This study provides novel information of the secretory proteins from the Brucella rough mutants and their effects on the Brucella cytotoxicity.
布氏 rough 突变体被报道可诱导感染的巨噬细胞死亡，这依赖于 IV 型分泌系统 (T4SS)。T4SS 及其分泌蛋白在宿主细菌相互作用中起着重要作用，但在布氏 rough 突变体感染过程中促进巨噬细胞死亡的关键分泌蛋白尚未被描述。在本研究中，我们发现 T4SS 成分在布氏 rough 突变体感染诱导的巨噬细胞死亡中不起作用，但一些 T4SS 效应子起作用。通过液相色谱/串联质谱分析布氏 rough 突变体 ΔrfbE 和 ΔrfbEΔvirB123 的分泌蛋白的蛋白质组学，鉴定出 861 个独特的蛋白质，其中 37 个是差异分泌蛋白。基因本体和途径分析表明，差异分泌蛋白参与细胞过程和代谢过程，分布在细胞和膜中，具有催化活性和结合的分子功能，并与核糖体、NOD 样受体信号通路、二组分系统和细菌分泌系统相关。细胞死亡分析表明，T4SS 效应子 VceC 以及两种差异分泌蛋白 OmpW 家族蛋白 (BAB1_1579) 和蛋白 BAB1_1185 与布鲁氏菌的细胞毒性有关。本研究为布鲁氏菌细胞毒性相关的分子机制提供了新的见解，并为布鲁氏菌疫苗候选物的筛选提供了有价值的信息。
布氏 rough 突变体诱导感染的巨噬细胞死亡，这依赖于 T4SS。在本报告中，比较蛋白质组学分析揭示了 Brucella rough 突变体 ΔrfbE 和 ΔrfbEΔvirB123 之间的 37 种差异分泌蛋白。进一步的研究表明，OmpW 家族蛋白 (BAB1_1579) 和未鉴定的蛋白 BAB1_1185 两种差异分泌蛋白与布鲁氏菌的细胞毒性有关。本研究提供了布氏 rough 突变体分泌蛋白的新信息及其对布鲁氏菌细胞毒性的影响。
