Genetic engineering of Ketogulonigenium vulgare for enhanced production of 2-keto-l-gulonic acid

► Over-expression of folate gene cluster increased folate concentration 8 times. ► Cell density and 2-KGA production increased by 18% and 14% in shake flasks. ► A 25% cell density and 35% 2-KGA productivity enhancement was observed in fermentor. ► This was the first successful study of metabolic engineering on K. vulgare.