首页 | 本学科首页   官方微博 | 高级检索  
     


Real‐time imaging of photodynamic action in bacteria
Authors:Anita Gollmer  Ariane Felgentraeger  Tim Maisch  Cristina Flors
Affiliation:1. Department of Dermatology, University Hospital Regensburg, Regensburg, Germany;2. Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia) and Nanobiotechnology Unit Associated to the National Center for Biotechnology (CSIC), Madrid, Spain
Abstract:Fluorescence imaging studies of the processes leading to photodynamic inactivation of bacteria have been limited due to the small size of microorganisms as well as by the faint fluorescence of most photosensitizers. A versatile method based on highly‐sensitive fluorescence microscopy is presented which allows to study, in real time, the incorporation of photosensitizers inside S. aureus upon photodynamic action. The method takes advantage of the fluorescence enhancement of phenothiazine and porphyrin photosensitizers upon entering the bacterial cytosol after the cell wall has been compromised. In combination with typical assays, such as the addition of specific enhancers of reactive oxygen species, it is possible to extract mechanistic information about the pathway of photodynamic damage at the single‐cell level. Imaging experiments in deuterated buffer strongly support a Type‐I mechanism for methylene blue and a very minor role of singlet oxygen.

Keywords:Fluorescence microscopy  photodynamic therapy  photosensitizers  reactive oxygen species  singlet oxygen  Staphylococcus aureus
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号