Peacock sole

Peacock sole Pavonininus pavonininus Pavonins Steroid monoglycosides Sharks Shark repellent, affect olfaction... 

For example, the skin secretion of the fish peacock sole Pardachirus pavoninus (Soleidae), occurring in the Indo-Pacific region, contains linear peptides produced by a series of toxic glands along the bases of dorsal- and anal-fin rays. These toxic peptides, composed of 33 amino (2800 Da), are called pardaxin 1, pardaxin 2 and pardaxin 3. For example, the primary structure of pardaxin 1 is formed by the following sequence of amino acids Gly-Phe-Phe-Ala-Leu-lle-Pro-Lys-lle-lle-Ser-Ser-Pro-Leu-Phe-Lys-Thr-Leu-Leu-Ser-Ala-Val-Gly-Ser-Ala-Leu-Ser-Ser-Ser-Gly-Glu-Gln-Glu. Other pardaxins have similar structures. As with other polypeptides, paradaxins are labile compounds that are relatively easily hydrolysed by proteolytic enzymes, and partly also by cooking. 

Other compounds present in the toxic secretion of peacock sole are glycosides of steroid toxins called pavoninins (10-259 to 10-262). The skin secretion of a related fish species known as finless sole (P. marmoratus) are structurally related lipophilic toxins called mosesins (10-259,10-260 and 10-262). 

Pardaxins 33 Red Sea Moses sole and peacock sole of the western Pacific [92-94]... 

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