Violacein

Lab experiments last year showed that J. liv produces a metabolite, violacein, that is toxic to the chytrid fungus. ❋ By ERICA REX (2010)

Colonies are purplish-black due to its water-insoluble pigment called violacein. ❋ Unknown (2009)

There is a correlation between violacein production, biofilm formation, and greater survival, suggesting that it may play a role in response to environmental stress. ❋ Unknown (2009)

While violacein benefits the host directly, it is also known to be toxic against protozoa, and fungi. ❋ Unknown (2009)

Results showed that adding J. lividum to the skin of the salamander increased the concentration levels of violacein already present and contributed to survival following experimental exposure to the fungus. ❋ Unknown (2009)

"Our study suggests that a threshold violacein concentration of about 18 μM on a salamander's skin prevents mortality and morbidity caused by B. dendrobatidis," say the researchers. ❋ Unknown (2009)

The bacterially produced metabolite violacein is associated with survival of amphibians infected with a lethal fungus. ❋ Unknown (2009)

In a prior study Janthinobacterium lividum was identified as a bacterium that produces the anti-B. dendrobatidis metabolite violacein. ❋ Unknown (2009)

"We show that over one-half of individuals in nature support antifungal bacteria that produce violacein, which suggests that there is a mutualism between violacein-producing bacteria and P. cinereus and that adding J. lividum is effective for protecting individuals that lack violacein-producing skin bacteria. ❋ Unknown (2009)

Plethodon cinereus) at concentration levels capable of inhibiting B. dendrobatidis, indicating a mutualistic community of violacein-producing bacteria. ❋ Unknown (2009)