biological activity of persian sturgeon recombinant growth hormone molecules trapped in inclusion bodies (ibs)

The biological activity of persian sturgeon (ps) enfolded crude recombinant growth hormone (rgh) recovered from inclusion bodies (ib) estimated by administrating to fish fingerlings. the psrgh ibs expressed in e. coli were dissolved in cold guanidine hcl solution, immediately diluted ~1000 fold in cold sodium chloride 0.9% solution do not allow the rgh folding and administrated to fishes. it was revealed that intramuscularly injections of rgh at dosage of 0.5 μg/ g once a week for 8 weeks significantly accelerate the growth of fishes. comparison of the mean growth rate and daily weight and length gain dates of persian sturgeon fingerlings administrated by pure and crude grade rgh revealed the existence at list 25% potentially biologically active psrgh molecules in ibs. this fact enables to avoid the time and cost consuming processes of refolding and purification of rghs.