Purification of molt-inhibiting hormone-like peptides with hyperglycemic activity from the eyestalks of the crab Scylla serrata

In the present study, putative molt-inhibiting hormone (MIH)-like peptides from the sinus glands of Scylla serrata (S. serrata) were characterized by high-performance liquid chromatography, followed by immunoassay and bioassay (inhibition of ecdysteroid synthesis by Y-organs). Results of double immunodiffusion demonstrated the cross-reactivity of Homarus americanus MIH antiserum with the S. serrata MIH-like peptides, indicating the existence of close immunological relationship between crab and lobster peptides. Of the three molt-inhibiting immuno-reactive peptides, two also possess significant hyperglycemic activity.