Extracellular expression, purification and bioreactor production of tambaqui (Colossoma macropomum) growth hormone in the yeast Komagataella phaffii (formerly Pichia pastoris)

ABSTRACT Due to its zootechnical importance, the gene encoding growth hormone (GH) from several fish species has been isolated and expressed in heterologous systems. In this study, we isolated the cDNA sequence of GH of tambaqui (Colossoma macropomum), a species native to the Amazon basin and considered promising for Brazilian fish farming, and expressed it in the yeast Komagataella phaffii GS115. Heterologous expression was regulated by the AOX1 promoter and recombinant tambaqui GH (rtGH) secreted to the culture supernatant via the alpha factor of Saccharomyces cerevisiae. The rtGH was successfully expressed in shaken flask and bioreactor systems and purified using affinity chromatography. In the bioreactor, the production reached 250 mg L-1. This is the first report of the heterologous expression, purification and production of rtGH in a bioreactor. Our results contribute to making tambaqui a target species for future biotechnological innovations based on the significant levels of rtGH obtained in the bioreactor and the future zootechnical applications of this protein, which can be exploited in aquaculture.