title: Selective production of 2,3-butanediol and acetoin by a newly isolated bacterium Klebsiella oxytoca M1.
abstract: A newly isolated bacterium, designated as Klebsiella oxytoca M1, produced 2,3-butanediol (2,3-BDO) or acetoin selectively as a major product depending on temperature in a defined medium. K. oxytoca M1 produced 2,3-BDO mainly (0.32~0.34 g/g glucose) at 30 °C while acetoin was a major product (0.32~0.38 g/g glucose) at 37 °C. To investigate factors affecting product profiles according to temperature, the expression level of acetoin reductase (AR) that catalyzes the conversion of acetoin to 2,3-BDO was analyzed using crude protein extracted from K. oxytoca M1 grown at 30 and 37 °C. The AR expression at 37 °C was 12.8-fold lower than that at 30 °C at the stationary phase and reverse transcription PCR (RT-PCR) analysis of the budC (encoding AR) was also in agreement with the AR expression results. When AR was overexpressed using K. oxytoca M1 harboring pUC18CM-budC, 2,3-BDO became a major product at 37 °C, indicating that the AR expression level was a key factor determining the major product of K. oxytoca M1 at 37 °C. The results in this study demonstrate the feasibility of using K. oxytoca M1 for the production of not only 2,3-BDO but also acetoin as a major product.
authors.affiliation: Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 136-791, Republic of Korea.
authors.forename: Sukhyeong
authors.initials: S
authors.lastname: Cho
authors.forename: Kyung Duk
authors.initials: KD
authors.lastname: Kim
authors.forename: Jae-Hyung
authors.initials: JH
authors.lastname: Ahn
authors.forename: Jinwon
authors.initials: J
authors.lastname: Lee
authors.forename: Seon-Won
authors.initials: SW
authors.lastname: Kim
authors.forename: Youngsoon
authors.initials: Y
authors.lastname: Um
mesh_terms: D000093:Acetoin / Q000302:isolation & purification / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D002072:Butylene Glycols / Q000302:isolation & purification / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D041121:Klebsiella oxytoca / Q000145:classification* / Q000378:metabolism*; D013045:Species Specificity; D013696:Temperature
chemical_list: D002072:Butylene Glycols; C026978:2,3-butylene glycol; D000093:Acetoin; D005947:Glucose