Procedure for the production and purification of somatostatin in escherichia coli cells from expression in the same of the coding gene cloned in the vector pgrv1.

Procedure for the production and purification of somatostatin in Escherichia coli cells from the expression therein of the coding gene cloned in the vector pGRV1. Through basic genetic engineering techniques, the N-terminal end of the beta-galactosidase of Kluyveromyces lactis has been cloned in the commercial plasmid pET17xb, generating two unique restriction sites that can be used for cloning of peptide coding sequences, giving rise to plasmid pGRV1. The somatostatin hormone coding sequence has been obtained by polymerase chain amplification (PCR) using overlapping oligonucleotides, subsequently cloning the gene into plasmid pGRV1, to give rise to plasmid pSOMA. Escherichia coli strain BL21 (DE3) was transformed with plasmid pSOMA giving rise to strain CECT5840. Using conventional fermentation equipment, sufficient amounts of fusion protein have been obtained, which, after digestion with cyanogen bromide, have been chromatographically purified. The peptide obtained shows chromatographic properties coinciding with those of a commercial standard.