Engineering of an l-arabinose metabolic pathway in Corynebacterium glutamicum

• Published in: Applied microbiology and biotechnology 2008, Vol.77 (5), p.1053-1062
• Main Authors: Kawaguchi, Hideo, Sasaki, Miho, Vertès, Alain A., Inui, Masayuki, Yukawa, Hideaki
• Format: Article
• Language: English
• Subjects: Acetic acid; Acetic Acid - metabolism; Acid production; Agricultural pollution; Anaerobiosis; Applied Genetics and Molecular Biotechnology; Arabinose - metabolism; Assimilation; Bioengineering; Biological and medical sciences; Biomass; Biotechnology; Carbon; Carbon - metabolism; Carboxylic Acids - metabolism; Commodities; Corynebacterium glutamicum; Corynebacterium glutamicum - genetics; Corynebacterium glutamicum - growth & development; Corynebacterium glutamicum - metabolism; Culture Media - chemistry; Dehydrogenases; E coli; Energy Metabolism; Energy sources; Escherichia coli; Escherichia coli - enzymology; Escherichia coli - genetics; Escherichia coli Proteins - biosynthesis; Escherichia coli Proteins - genetics; Ethanol; Fermentation; Fundamental and applied biological sciences. Psychology; Gene Expression; Genes; Glucose; Glucose - metabolism; Gram-positive bacteria; Industrial production; Lactic Acid - metabolism; Life Sciences; Lignocellulose; Metabolic Networks and Pathways; Metabolism; Microbial Genetics and Genomics; Microbiology; Organic acids; Phosphotransferases (Alcohol Group Acceptor) - biosynthesis; Phosphotransferases (Alcohol Group Acceptor) - genetics; Plasmids; Raw materials; Studies; Succinic Acid - metabolism; Sugar; Yeast
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-007-1244-x

Corynebacterium glutamicum was metabolically engineered to broaden its substrate utilization range to include the pentose sugar l -arabinose, a product of the degradation of lignocellulosic biomass. The resultant CRA1 recombinant strain expressed the Escherichia coli genes araA , araB , and araD encoding l -arabinose isomerase, l -ribulokinase, and l -ribulose-5-phosphate 4-epimerase, respectively, under the control of a constitutive promoter. Unlike the wild-type strain, CRA1 was able to grow on mineral salts medium containing l -arabinose as the sole carbon and energy source. The three cloned genes were expressed to the same levels whether cells were cultured in the presence of d -glucose or l -arabinose. Under oxygen deprivation and with l -arabinose as the sole carbon and energy source, strain CRA1 carbon flow was redirected to produce up to 40, 37, and 11%, respectively, of the theoretical yields of succinic, lactic, and acetic acids. Using a sugar mixture containing 5% d -glucose and 1% l -arabinose under oxygen deprivation, CRA1 cells metabolized l -arabinose at a constant rate, resulting in combined organic acids yield based on the amount of sugar mixture consumed after d -glucose depletion (83%) that was comparable to that before d -glucose depletion (89%). Strain CRA1 is, therefore, able to utilize l -arabinose as a substrate for organic acid production even in the presence of d -glucose.