Clonagem e expressão do hormônio de crescimento de Colossoma macropomum em Escherichia coli.

Abstract

Growth hormone is a polypeptide essential for growth and development of vertebrates. The tambaqui (Colossoma macropomum) is a widely distributed fish species in the Amazon basin, considered as promising for farming. Aiming future applications in dietary supplementation of fish, this work has cloned and expressed the growth hormone from tambaqui (tGH), using the bacterium Escherichia coli strain BL21 DE3 as a host. For expression of heterologous protein, the synthetic gene tGH (611pb) was initially cloned into pUC19 vector and subsequently inserted into the vector PGSM-1, constructed specifically for this work, giving rise to plasmid PGSM-TGH. Induction of HGT was obtained by cultivating cells of E. coli / PGSM-GHT in the presence of the inducer IPTG (1 mM), where the peak of expression was observed after 4h of induction. Recombinant clones expressed a protein of approximately 24 kDa, similar in size to other works with fish GH. The recombinant tGH was confirmed by polyacrylamide gel electrophoresis SDS-PAGE 15%. The recombinant tGH coli described in this work will be used in ongoing studies, allowing additional characterization. Finally, the recombinant TGH should be further evaluated as a food supplement in the diet of fish, in order to provide greater economic value to the fish farming of tambaqui.