Human milk oligosaccharides (HMOs) may be used e.g. as functional ingredients in infant nutrition, medical nutrition, functional foods and animal feed. There is still a need of improved means of producing HMOs. The present invention provides genetically modified microorganisms for the improved production of HMOs and HMO production methods using the same. The microorganisms of the invention may have one or more yield-enhancing modifications, including an inducible lysis system, which allows for the easy extraction of intracellular and extracellular HMOs, lactose permease mutants, which may increase intracellular lactose levels, or chaperones, which may increase intracellular availability of key enzymes for the production of HMOs.
