Effects of hydrogen peroxide on light emission by various strains of marine luminescent bacteria

Abstract

Light-emitting bacteria are the most abundant and widespread luminescent organisms. Most species of such bacteria live in marine environments. However, until recently, biological role of bacterial luminescence remained unknown. Recent studies indicated that light produced in bacterial cells may stimulate DNA repair. Therefore, it is not surprising that agents that cause DNA damage induce expression of lux genes. Moreover, it was proposed previously that bacterial luciferases may be involved in detoxification of reactive oxygen species. Recently, this hypothesis was confirmed experimentally. Here we investigated effects of hydrogen peroxide on light emission by various strains of luminescent bacteria. We found that luminescence of strains with luciferase of fast kinetics of reaction decreased at considerably lower concentrations of H2O2 than that of strains with luciferase of the slow kinetics. The action (either direct or indirect) of luciferases as anti-oxidants seemed to be independent of activity of catalase, which was found to be different in various strains. Therefore, it seems that luciferases of the slow kinetics are more efficient in detoxification of reactive oxygen species than those of the fast kinetics.

The Mycobacterium marinum mel2 locus displays similarity to bacterial bioluminescence systems and plays a role in defense against reactive oxygen and nitrogen species

“…These data are particularly interesting in light of the recent observations that bioluminescent systems can protect cells against oxidative stress [28-32]. In search of a biological role for bioluminescence in bacteria that would explain how such an energy-consuming system could have developed evolutionarily, it has been proposed that these pathways protect against ROS generated in an aerobic atmosphere [35,54].…”

“…Bioluminescence systems can protect cells against ROS [28-32] through a catalase-like reaction between the electron donating ROS and oxidized luciferase-bound flavin mononucleotide, producing water and light [33]. The similarity of luciferases to oxidases [34] suggests that bioluminescence systems could have evolved from oxygen defense mechanisms [35].…”

A Novel lux Operon in the Cryptically Bioluminescent Fish Pathogen Vibrio salmonicida Is Associated with Virulence

“…We hypothesize that the attenuation may be directly due to the loss of luciferase, which results in the elimination of the dark luciferase reaction. The dark luciferase reaction produces toxic oxygen radicals that may serve as a direct virulence agent or a stimulant for bacterial DNA repair (15,22,23,25). Alternatively, the luciferase reaction may function as an alternative pathway to provide oxidized flavin at low oxygen tensions which may aid colonization if oxygen becomes limited (4,26).…”

Examination of the Mechanism of Phenanthrenequinone Toxicity To Vibrio Fischeri: Evidence for a Reactive Oxygen Species‐Mediated Toxicity Mechanism

“…The lysates were then centrifuged at 10,000 g for 10 min, and the supernatants were used for enzyme activity assays via native polyacrylamide gel electrophoresis (PAGE) or spectrophotometry. Total catalase activity was spectrophotometrically measured by the disappearance of H 2 O 2 at 240 nm [21]. Bacterial extracts (50 μl) were mixed with 1 ml of 2% NaCl containing 30 μl of 3% H 2 O 2 .…”