A proposed functional role for indole derivatives in reproduction and defense of the Muricidae (Neogastropoda : Mollusca)

The Muricidae, also known as Murex or purple snails, are remarkable both as a source of the ancient indigoid dye, Tyrian purple and the homeopathic remedy "Murex", prescribed for the relief of women's problems. This purple secretion contains brominated indoles and indirubins with established antibiotic and anticancer properties, as well as choline esters with muscle relaxing activity. These properties have prompted considerable speculation, but little directed research, into the selective benefits of these bioactive compounds for the Muricidae. Consequently, this paper reviews the current literature on indole derivatives, their biosynthesis and associated bioactivities, with the aim of amassing evidence for a naturally selected function in the Muricidae.