1. A recombinant vector for expressing and secreting, by a propionibacterium , at least one eukaryotic peptide or protein of interest, comprising at least: under the control of at least one suitable promoter, at least one nucleic acid sequence encoding a propionibacterial signal peptide and, at least one nucleic acid sequence encoding said eukaryotic peptide or protein of interest; wherein said at least one nucleic acid sequence encoding a propionibacterial signal peptide is translationally fused to said at least one nucleic acid sequence encoding said eukaryotic peptide or protein of interest.