(448e) Analysis of Amino Acids Metabolism in Butanol Fermentation By Clostridium Tyrobutyricum

The objective of this study was to understand the metabolism of amino acids in biobutanol production by the engineered Clostridium tyrobutyricum, AKOKO-adhE2. First, we investigated the expression of the proteins involved in amino acids consumption and metabolism using proteomics analysis. The proteomics study showed that the expression of amino acid ABC transporter substrate binding protein was upregulated while the aminotransferase was downregulated during butanol production. The amino acids associated with the intermediates in the central metabolic pathway of butanol formation were then analyzed. The metabolites analysis indicated that the uptake rate of alanine (associated with pyruvate), leucine and oxoproline (acetyl-CoA) was reduced while the consumption rate of α-ketoglutamate and succinate (butyryl-CoA) was increased with the production of butanol. Butanol production was increased from 15 g/L to 19 g/L by yeast extract supplement. Finally the kinetics profiles of all 20 amino acids were collected to develop a systematic understanding of amino acids metabolism, which could be used to rationally optimize the butanol production medium or regulate the metabolism of the key metabolite in butanol production.