Production of reactive oxygen species (ROS) is an important part of a hosts response to an infection. Examples of ROS include oxygen ions and peroxides that can damage bacterial cell structure. Analysis of ROS production was one of the factors studied in the recent paper 'Comparison of host response mechanisms evoked by extended spectrum beta lactamase (ESBL)- and non-ESBL-producing uropathogenic E. coli' which was published in BioMed Central Microbiology.
ROS-production was monitored with a luminol-horseradish peroxidase (HRP) assay using the FLUOstar Optima microplate reader from BMG LABTECH. In this assay luminol is activated by hydrogen peroxide and the resulting luminescence is proportional to ROS-production. The authors found the ESBL-producing bacteria produce higher levels of ROS and that this correlates with the decreased virulence of this bacteria.
The luminol-HRP assay is one of many approaches available to assess ROS levels. BMG LABTECH application notes have previously described other luminescent (lucigenin) or fluorescent (DCFH) probes that similarly monitor ROS levels. These approaches are suitable for use on all the classes of microplate readers from BMG LABTECH such as the Omega, PHERAstar and CLARIOstar.