A peptide sequence of a guide protein for the production of a peptide of interest; a peptide sequence that has a similarity of at least 90% to SEQ. ID. NO 1; a nucleotide sequence encoding the guide protein; an expression vector comprising the nucleotide sequence; a host cell that expresses a fusion protein comprising a peptide of interest; a method of production of a peptide of interest, comprising the steps of A) constructing an expression vector; B) inserting the expression vector into a host cell; C) expressing the fusion protein, culturing the host cell in a culture medium; D) recovering the accumulated fusion protein in the host cell; E) cleaving the fusion protein; F) purifying the peptide of interest.