Microbial synthesis of 3-dehydroshikimic acid: a comparative analysis of D-xylose, L-arabinose, and D-glucose carbon sources.
3-Dehydroshikimic acid is a hydroaromatic precursor to chemicals ranging from L-phenylalanine to adipic acid. The concentration and yield of 3-dehydroshikimic acid microbially synthesized from various carbon sources has been examined under fed-batch fermentor conditions. Examined carbon sources included D-xylose, L-arabinose, and D-glucose. A mixture consisting of a 3:3:2 molar ratio of glucose/xylose/arabinose was also evaluated as a carbon source to model the composition of pentose streams potentially resulting from the hydrolysis of corn fiber. Escherichia coli KL3/pKL4.79B, which overexpresses feedback-insensitive DAHP synthase, synthesizes higher concentrations and yields of 3-dehydroshikimic acid when either xylose, arabinose, or the glucose/xylose/arabinose mixture is used as a carbon source relative to when glucose alone is used as a carbon source. E. coli KL3/pKL4.124A, which overexpresses transketolase and feedback-insensitive DAHP synthase, synthesizes higher concentrations and yields of 3-dehydroshikimic acid when the glucose/xylose/arabinose mixture is used as the carbon source relative to when either xylose or glucose is used as a carbon source. Observed high-titer, high-yielding synthesis of 3-dehydroshikimic acid from the glucose/xylose/arabinose mixture carries significant ramifications relevant to the employment of corn fiber in the microbial synthesis of value-added chemicals.
Li
K
K
Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
Frost
J W
JW
D001089:Arabinose / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D012765:Shikimic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D014174:Transketolase / Q000096:biosynthesis / Q000378:metabolism; D014994:Xylose / Q000378:metabolism*
C096387:3-dehydroshikimate; D012765:Shikimic Acid; D014994:Xylose; D001089:Arabinose; D014174:Transketolase; D005947:Glucose