Synthesis of partial amino acid sequence of crustacean hyperglycemic hormone from Macrobrachium rosenbergii for antibody production against crustacean hyperglycemic hormone
Abstract:
Heptapeptide (YANAVQV-NH2 = T-) and octapeptide (YANAVQTV-NH2 = T+), the putative C-terminal of crustacean hyperglycemic hormone (CHH) from the eyestalk of the giant freshwater prawn Macrobrachium rosenbergii, were synthesized by solid phase peptide synthesis and conjugated to bovine serum albumin, then used to immunize swiss mice. The titer and quality of the anti-peptide antibodys were determined by indirect immunoperoxidase ELISA and dot-ELISA. The serum contain high titer of each antipeptide antibody was used to detect the presence of the natural CHH in the eyestalk extract after separated by one step RP-HPLC with Dot-ELISA. The immunoreactive substances were found in fraction 30 with anti T- antibody and in fraction 38 with anti T+ antibody. However, the CHH bioactivity was found in only fraction 37-39. Immunocytochemical localization using the anti T- antibody did not show any specific staining, but the anti T+ antibody revealed staining on a group of 24+-5 neurons with diameter 18+-3 um in Medulla Terminalis Ganglioic X-organ (MTGXO) and their processes leading to the sinus gland. These evidences show strong indication that the anti T+ antibody can bind to the natural CHH therefore this isoform of the CHH in M.rosenbergii consists of 72 residues and threonine is likely to be present at position 71.