RATIONALE Antimicrobial photodynamic treatment is potentially an alternative to antibiotics and is also effective against viruses, fungi and some cancers. Our previous studies have shown that blue light combined with curcumin, a chemical from the turmeric plant, exerted effective antimicrobial activity via photodynamic treatment. The study reported in this paper investigates which target proteins are affected after the treatment. METHODS We treated imipenem-resistant Acinetobacter baumannii with blue light and curcumin and used protein carbonylation as a marker for oxidative damage. After treatment, the bacterial proteins were extracted and the protein carbonyls marked using dinitrophenylhydrazide. After enzyme digestion, we used liquid chromatography/nano-electrospray ionization (LC/nano-ESI) ion trap mass spectrometry to identify bacterial peptides from a customized database. The functional enrichment analyses of the identified proteins were performed using gene ontology annotation and the STRING protein-protein interaction network. RESULTS The application of curcumin with blue light showed good antibacterial activity against imipenem-resistant A. baumannii. Using a shotgun proteomics approach, the carbonylated proteins in A. baumannii caused by the photolytic curcumin were identified. The results showed that the proteins related to membrane structures, translation and response to oxidative stress were preferentially modified. CONCLUSIONS The photolytic curcumin treatment could be a potential alternative to antibiotics for bacterial infection. In this study, the shotgun proteomics strategy allows us to explore the possible bactericidal mechanisms under this oxidative stress. The result provides a reference for future studies on the enhancement of the action of photolytic curcumin.

中文翻译：

---

在耐亚胺培南的鲍曼不动杆菌上用蓝光照射姜黄素诱导的杀菌过程中羰基化蛋白的鉴定。

理由光抗微生物的光动力疗法可能是抗生素的替代品，并且也有效对抗病毒，真菌和某些癌症。我们以前的研究表明，蓝光与姜黄素（一种来自姜黄植物的化学物质）结合，通过光动力处理发挥了有效的抗菌活性。本文报道的研究调查了治疗后哪些靶蛋白受到影响。方法我们用蓝光和姜黄素处理了耐亚胺培南的鲍曼不动杆菌，并使用蛋白质羰基化作为氧化损伤的标记。处理后，提取细菌蛋白质，并使用二硝基苯酰肼标记蛋白质的羰基。酶消化后 我们使用液相色谱/纳米电喷雾电离（LC / nano-ESI）离子阱质谱法从定制数据库中鉴定细菌肽。使用基因本体注释和STRING蛋白质-蛋白质相互作用网络对鉴定出的蛋白质进行功能富集分析。结果姜黄素在蓝光下的应用对耐亚胺培南的鲍曼不动杆菌具有良好的抗菌活性。使用a弹枪蛋白质组学方法，鉴定了由光解姜黄素引起的鲍曼不动杆菌中的羰基化蛋白。结果表明，与膜结构，翻译和对氧化应激反应有关的蛋白质被优先修饰。结论光解姜黄素治疗细菌感染可能是抗生素的潜在替代方法。在这项研究中，shot弹枪蛋白质组学策略使我们能够探索在这种氧化胁迫下可能的杀菌机理。该结果为今后进一步研究光解姜黄素的作用提供了参考。