title: One-step biosynthesis of α-ketoisocaproate from L-leucine by an Escherichia coli whole-cell biocatalyst expressing an L-amino acid deaminase from Proteus vulgaris.
abstract: This work aimed to develop a whole-cell biotransformation process for the production of α-ketoisocaproate from L-leucine. A recombinant Escherichia coli strain was constructed by expressing an L-amino acid deaminase from Proteus vulgaris. To enhance α-ketoisocaproate production, the reaction conditions were optimized as follows: whole-cell biocatalyst 0.8 g/L, leucine concentration 13.1 g/L, temperature 35 °C, pH 7.5, and reaction time 20 h. Under the above conditions, the α-ketoisocaproate titer reached 12.7 g/L with a leucine conversion rate of 97.8%. In addition, different leucine feeding strategies were examined to increase the α-ketoisocaproate titer. When 13.1 g/L leucine was added at 2-h intervals (from 0 to 22 h, 12 addition times), the α-ketoisocaproate titer reached 69.1 g/L, while the leucine conversion rate decreased to 50.3%. We have developed an effective process for the biotechnological production of α-ketoisocaproate that is more environmentally friendly than the traditional petrochemical synthesis approach.
authors.affiliation: 1] Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [2] Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [3] Synergetic Innovation Center Of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Song
authors.affiliation: 1] Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [2] Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [3] Synergetic Innovation Center Of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Jianghua
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Chemical and Biomolecular Engineeirng, Georgia Institute of Technology, Atlanta 30332, USA.
authors.forename: Hyun-dong
authors.initials: HD
authors.lastname: Shin
authors.affiliation: 1] Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [2] Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [3] Synergetic Innovation Center Of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Guocheng
authors.initials: G
authors.lastname: Du
authors.affiliation: 1] Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [2] Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [3] Synergetic Innovation Center Of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Long
authors.initials: L
authors.lastname: Liu
authors.affiliation: 1] Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China [2] Synergetic Innovation Center Of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
mesh_terms: D000642:Ammonia-Lyases / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods; D001711:Biotransformation / Q000502:physiology; D004926:Escherichia coli / Q000378:metabolism*; D007651:Keto Acids / Q000378:metabolism*; D007930:Leucine / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000502:physiology*; D011514:Proteus vulgaris / Q000378:metabolism*
chemical_list: D007651:Keto Acids; C013082:alpha-ketoisocaproic acid; D000642:Ammonia-Lyases; D007930:Leucine