Abstract: There is provided a method to increase the production of a desired protein in a microorganism by introduction of slowly translated codons in the encoding DNA gene sequence capable of slowing down the translation speed of the ribosomes moving along the mRNA, whereby the ribosomes protect the mRNA from being enzymatically degraded. This increases the stability of the mRNA transcript and thus results in an increased production of the desired protein. Moreover, there is provided a method of decreasing the half-life of a mRNA transcript from a gene encoding a peptide.