Data_Sheet_2_Integrating proteomic data with metabolic modeling provides insight into key pathways of Bordetella pertussis biofilms.docx

Pertussis, commonly known as whooping cough is a severe respiratory disease caused by the bacterium, Bordetella pertussis. Despite widespread vaccination, pertussis resurgence has been observed globally. The development of the current acellular vaccine (ACV) has been based on planktonic studies. However, recent studies have shown that B. pertussis readily forms biofilms. A better understanding of B. pertussis biofilms is important for developing novel vaccines that can target all aspects of B. pertussis infection. This study compared the proteomic expression of biofilm and planktonic B. pertussis cells to identify key changes between the conditions. Major differences were identified in virulence factors including an upregulation of toxins (adenylate cyclase toxin and dermonecrotic toxin) and downregulation of pertactin and type III secretion system proteins in biofilm cells. To further dissect metabolic pathways that are altered during the biofilm lifestyle, the proteomic data was then incorporated into a genome scale metabolic model using the Integrative Metabolic Analysis Tool (iMAT). The generated models predicted that planktonic cells utilised the glyoxylate shunt while biofilm cells completed the full tricarboxylic acid cycle. Differences in processing aspartate, arginine and alanine were identified as well as unique export of valine out of biofilm cells which may have a role in inter-bacterial communication and regulation. Finally, increased polyhydroxybutyrate accumulation and superoxide dismutase activity in biofilm cells may contribute to increased persistence during infection. Taken together, this study modeled major proteomic and metabolic changes that occur in biofilm cells which helps lay the groundwork for further understanding B. pertussis pathogenesis.

百日咳（Pertussis），英文俗称whooping cough，是由百日咳博德特氏菌（Bordetella pertussis）引发的严重呼吸道传染病。尽管疫苗接种已广泛普及，全球范围内仍观测到百日咳的复燃现象。当前使用的无细胞疫苗（acellular vaccine, ACV）的研发，均基于浮游态菌体研究开展，但近期研究表明，百日咳博德特氏菌极易形成生物被膜（biofilms）。深入解析百日咳博德特氏菌生物被膜的特性，对于开发能够全面覆盖其感染各个环节的新型疫苗具有重要意义。本研究对比了生物被膜态与浮游态百日咳博德特氏菌的蛋白质组表达谱，以明确两种生长状态下的关键差异。研究发现，生物被膜态菌体在毒力因子方面存在显著差异：腺苷酸环化酶毒素（adenylate cyclase toxin）与皮肤坏死毒素（dermonecrotic toxin）的表达显著上调，而pertactin与Ⅲ型分泌系统（type III secretion system）蛋白的表达则显著下调。为进一步解析生物被膜生长状态下发生改变的代谢通路，本研究借助整合代谢分析工具（Integrative Metabolic Analysis Tool, iMAT）将蛋白质组数据整合至全基因组规模代谢模型中。构建完成的模型预测显示：浮游态菌体利用乙醛酸分流（glyoxylate shunt）途径代谢，而生物被膜态菌体则完整运行三羧酸循环（tricarboxylic acid cycle）。研究还发现，菌体在天冬氨酸、精氨酸与丙氨酸的代谢处理过程中存在差异；此外，生物被膜态菌体存在独特的缬氨酸分泌现象，这可能在细菌间通讯与调控中发挥作用。最后，生物被膜态菌体的聚羟基丁酸酯（polyhydroxybutyrate）积累量与超氧化物歧化酶（superoxide dismutase）活性均有所提升，这可能有助于增强其在感染过程中的存续能力。综上，本研究解析了生物被膜态百日咳博德特氏菌的主要蛋白质组与代谢组变化，为进一步阐明百日咳博德特氏菌的致病机制奠定了基础。