The invention provides a genetically modified eukaryotic microorganism for anaerobic production of essential amino acids and optionally the co-production of one or more co-products. The microorganism is genetically modified to redirect carbon flow from PEP via oxaloacetate and asparatate semialdehyde, towards the synthesis of increased amounts of essential amino acids. The microorganism may be genetically modified to produce increased amounts of one or more co-product by enhancing carbon flow from PEP via pyruvate, acetyl CoA and malonyl CoA to produce alcohols and lipids, such as triglycerides, fatty esters, fatty alcohols, fatty aldehydes, fatty amides. The invention provides a method for anaerobic production of essential amino acids using the genetically modified eukaryotic microorganism and optionally co-production of said one or more co-products. The genetically modified eukaryotic microorganism may be used for the anaerobic production of essential amino acids and optionally the co-production of said one or more co-products.