Effect of hyperbaric oxygen on Vibrio vulnificus and murine infection caused by it.

Vibrio vulnificus is a bacterium known to cause fatal necrotizing soft tissue infection in humans. Here, a remarkable therapeutic effect of hyperbaric oxygen (HBO) on V. vulnificus infection provoked by its injection into mouse footpads is described. HBO was shown to be bactericidal to this bacterium in vitro as well as in the infected tissue. The bactericidal activity of HBO was shown to be due to reactive oxygen species (ROS), the efficacy of HBO against V. vulnificus infection being accounted for by the high sensitivity of this bacterium to ROS. Besides being somewhat weak in ROS-inactivating enzyme activities, this bacterium is also unusually sensitive to ultraviolet light and other DNA-damaging agents. It seems likely that the sensitivity of V. vulnificus to HBO is mainly due to its poor ability to repair oxidative damage to DNA. These findings encourage clinical application of HBO against potentially fatal V. vulnificus infection in humans.