นโยบายงานวิจัย /จรรยาบรรณนักวิจัย /ระดับคุณภาพบทความวิจัยตีพิมพ์ /ระดับคุณภาพผลงานวิชาการ /แหล่งทุน /ดาวน์โหลด /ฐานข้อมูลวิจัย /วิเคราะห์-สังเคราะห์งานวิจัย /ลิขสิทธิ์ /ข่าว


Efficient reduction of the formation of by-products and improvement of production yield of 2,3-butanediol by a combined deletion of alcohol dehydrogenase, acetate kinase-phosphotransacetylase, and lactate dehydrogenase genes in metabolically engineered Klebsiella oxytoca in mineralsaltsmedium

Author

-

Kaemwich Jantama, Pattharasedthi Polyiam, Panwana Khunnonkwao, Sitha Chan, Maytawadee Sangproo, Kirin Khor, Sirima Suvarnakuta Jantama, Sunthorn Kanchanatawee


Journal

- Metabolic Engineering

Volume

- 30

Year

- 2015

Publication type

- Research article (Inter)

Page list

- 16-26

Abstract

   

Klebsiella oxytoca KMS005 (ΔadhEΔackA-ptaΔldhA) was metabolically engineered to improve2,3-butanediol (BDO) yield. Elimination of alcoholdehydrogenase E (adhE), acetate kinase A-phosphotransacetylase (ackA-pta), and lactate dehydrogenase A (ldhA) enzymes allowed BDO production as a primary pathway for NADH re-oxidation, and significantly reduced by-products. KMS005 was screened for the efficient glucose utilization by metabolic evolution. KMS005-73T improved BDO production at a concentration of 23.5 ± 0.5 g/L with yeild of 0.46 ± 0.02 g/g in mineral salts medium containing 50g/L glucose in a shake flask. KMS005-73T also exhibited BDO yields of about 0.40–0.42 g/g from sugarcane molasses, cassava starch, and maltodextrin. During fed-batch fermentation, KMS005-73T produced BDO at a concentration, yield, and overall and specific productivities of 117.4 ± 4.5 g/L, 0.49 ± 0.02 g/g, 1.20 ± 0.05  g/L h, and 27.2 ± 1.1g/gCDW, respectively. No acetoin, lactate, and formate were detected, and only trace amounts of acetate and ethanol were formed. The strain also produced the least by-products and the highest BDO yield among other Klebsiella strains previously developed.


Keywords

   

Klebsiella oxytoca, 2,3-Butanediol, Metabolic engineering