Table_1_Peptidylarginine Deiminase Inhibitors Reduce Bacterial Membrane Vesicle Release and Sensitize Bacteria to Antibiotic Treatment.DOCX

Outer membrane and membrane vesicles (OMV/MV) are released from bacteria and participate in cell communication, biofilm formation and host-pathogen interactions. Peptidylarginine deiminases (PADs) are phylogenetically conserved enzymes that catalyze post-translational deimination/citrullination of proteins, causing structural and functional changes in target proteins. PADs also play major roles in the regulation of eukaryotic extracellular vesicle release. Here we show phylogenetically conserved pathways of PAD-mediated OMV/MV release in bacteria and describe deiminated/citrullinated proteins in E. coli and their derived OMV/MVs. Furthermore, we show that PAD inhibitors can be used to effectively reduce OMV/MV release, both in Gram-negative and Gram-positive bacteria. Importantly, this resulted in enhanced antibiotic sensitivity of both E. coli and S. aureus to a range of antibiotics tested. Our findings reveal novel strategies for applying pharmacological OMV/MV-inhibition to reduce antibiotic resistance.

外膜与膜囊泡（Outer membrane and membrane vesicles，OMV/MV）可从细菌中释放，并参与细胞通讯、生物膜形成以及宿主-病原体互作过程。肽基精氨酸脱亚胺酶（Peptidylarginine deiminases，PADs）是一类系统发育保守的酶，可催化蛋白质发生翻译后脱亚胺化/瓜氨酸化修饰，进而改变靶蛋白的结构与功能。PADs还在真核细胞外囊泡的释放调控中发挥关键作用。本研究揭示了细菌中由PADs介导的OMV/MV释放的系统发育保守通路，并解析了大肠杆菌（Escherichia coli，E. coli）及其衍生的OMV/MV中的脱亚胺化/瓜氨酸化蛋白。此外，本研究证实PAD抑制剂可有效降低革兰氏阴性菌与革兰氏阳性菌中的OMV/MV释放量。尤为重要的是，该处理可增强大肠杆菌与金黄色葡萄球菌（Staphylococcus aureus，S. aureus）对多种受试抗生素的敏感性。本研究结果为采用药理学手段抑制OMV/MV释放以降低抗生素耐药性提供了全新策略。