Abstract: Novel tailor-made artificial non-ribosomal peptide synthetases (NRPSs) for non-ribosomal synthesis and/or modification of peptides of a predetermined length and composition and/or for modification of individual amino acids are described. The fusion of building units of said peptide synthetases in particular linker regions makes it possible to specifically prepare by means of “modular molecule construction kits” NRPSs which are capable of synthesizing peptides of a desired structure.

Abstract: Novel tailor-made artificial non-ribosomal peptide synthetases (NRPSs) for non-ribosomal synthesis and/or modification of peptides of a predetermined length and composition and/or for modification of individual amino acids are described. The fusion of building units of said peptide synthetases in particular linker regions makes it possible to specifically prepare by means of “modular molecule construction kits” NRPSs which are capable of synthesizing peptides of a desired structure.

Abstract: The present invention relates to a method for providing bacterial or yeast cells with the capacity to produce a protein, the amino acid sequence of which comprises at least one unconventional amino acid. The method involves (a) introducing at least one missense mutation in a target codon of a gene encoding a protein required for the growth of the bacterial or yeast cells, where the mutated protein synthesized from the mutated gene is not functional in the bacterial or yeast cells. The method also involves (b) selecting the bacterial or yeast cells obtained in (a) in a culture medium which (1) does not contain a nutrient compensating for the loss of functionality of the mutated protein and (2) contains an unconventional amino acid which restores the functionality of the protein required for growth of the bacterial or yeast cells, in which the unconventional amino acid is that encoded by the target codon.

Abstract: The invention concerns mutant prokaryotic cells, in particular E. coli, capable of producing proteins whereof the amino acid sequences comprise at least a non-conventional amino acid, methods for producing and purifying said proteins and the proteins obtained by said methods. The invention also concerns uses of said cells and proteins in different fields such as in therapy, cosmetics, diagnosis or biosynthesis or biodegradation of organic compounds.