Described are recombinant Escherichia coli Nissle 1917 ("EcN") cellstransformed withgenes that express proteins or polypeptides involved in omega 3 fatty acidbiosynthesis.The recombinant EcN cells produce eicosapentaenoic acid (EPA) and/ordocosahexaenoic acids (DHA). Associated compositions, methods and uses of therecombinant EcN cells are also provided.