Comprehensive transcriptional profile of Gram-positive bacteria treated with Escherichia coli EVs

Extracellular vesicles (EVs) are 20-250 nm particles released extracellularly from the surface layer of many bacteria. It has been widely known that bacterial EVs encapsulate a variety of molecules including proteins and nucleic acids. And these enclosing molecules have a wide range of functions, including being involved in bacterial pathogenicity and survival strategies. We found that the growth of Streptococcus pyogenes or Methicillin-resistant Staphylococcus aureus (MRSA) treated with Escherichia coli EVs are remarkably decreased more than two times, suggesting that E. coli EVs significantly inhibit the growth of other bacterial species. In this study, we performed a comprehensive transcriptional profile of the bacteria cell treated with E. coli vesicles and demonstrate the mechanisms of how EVs contribute to inter-bacterial communications.

细胞外囊泡（Extracellular vesicles，EVs）是一类直径为20~250纳米的颗粒，由多种细菌的表层分泌至胞外。目前学界已广泛证实，细菌来源的细胞外囊泡可包裹包括蛋白质与核酸在内的多种生物分子。这类被包裹的分子具备多样生物学功能，参与细菌的致病过程与生存策略调控。本研究发现，经大肠埃希菌（Escherichia coli）细胞外囊泡处理后，化脓性链球菌（Streptococcus pyogenes）与耐甲氧西林金黄色葡萄球菌（Methicillin-resistant Staphylococcus aureus，MRSA）的生长量显著降低两倍以上，提示大肠埃希菌细胞外囊泡可有效抑制其他细菌物种的增殖。本研究对经大肠埃希菌细胞外囊泡处理的细菌细胞开展了全面的转录组分析，并阐明了细胞外囊泡介导细菌间通讯的具体分子机制。