Behavior, Ecology and Toxicity of Venomous Marine Fishes.

The writer has been studying the general biology of certain venomous marine fishes of nuisance importance to Navy personnel the cheimstry and electron microscope appearance of the skin of certain fishes recently found to be toxic the ultrastructure of the venom apparatus of the stingrays and scorpion fishes the chemistry and pharmacology of stingray and scorpionfish venom. Work on the chemistry of California scorpion fish venom indicate that sulfhydryl groups are required for the lethal activity of the venom. Cystine and reduced glutathione appear to have no significant effect on this activity until several days have passed. Clelands reagent, an effective sulfhydryl reagent, stabilizes the lethal activity. The lethal activity is sensitive to heat, oxidizing agents and extremes of concentration and pH. The venom contains nonsignificant amounts of proteolytic and phosphodiesterase activity. When the crude venom is fractionated by gel filtration chromatography, the lethal activity is associated with proteins having a molecular weight of more than 40,000 and would seem to have a molecular weight of less than 2,000,000. Following separation on Sephadex G-200, the semi-purified lethal fraction has an IV LD sub 50 in mice of 0.9 mgproteinkg body weight, while the LD sub 50 of the crude venom is 2.6 mgproteinkg.