Metabolic Engineering of Pichia pastoris for Production of Glucaric Acid

Abstract:

Glucaric acid is a kind of organic acid with important biological values. In order to achieve high-yield production of glucaric acid，a glucaric acid synthetic pathway was constructed in Pichia pastoris by co-expression of the mouse MIOX gene and the udh gene from Pseudomonas putida KT2440，which led to accumulation of glucaric acid. By fermentation optimization in shake flasks，the results showed the optimum carbon source was glucose（60 g/L was the best initial concentration），the optimum initial pH was 5.5，the optimum seed time was 24 h，and the optimum inoculation amount was 25%. The glucaric acid production was increased from （566.36±16.98） mg/L to （967.60±3.90） mg/L after optimization. According to the optimized conditions，the production of glucaric acid was substantially increased to （2.60±0.04） g/L in a 3 L fermentor.