Open AccessEngineering Pseudomonas putida S12 for Efficient Utilization of d -Xylose and l -Arabinose
Author(s) -
Jean-Paul Meijnen,
Johannes H. de Winde,
Harald J. Ruijssenaars
Publication year - 2008
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.00924-08
Subject(s) - xylose , pseudomonas putida , arabinose , xylose isomerase , chemistry , biochemistry , yield (engineering) , xylose metabolism , substrate (aquarium) , isomerase , fermentation , biology , enzyme , materials science , ecology , metallurgy
The solvent-tolerant bacteriumPseudomonas putida S12 was engineered to utilize xylose as a substrate by expressing xylose isomerase (XylA) and xylulokinase (XylB) fromEscherichia coli . The initial yield on xylose was low (9% [g CDW g substrate−1 ], where CDW is cell dry weight), and the growth rate was poor (0.01 h−1 ). The main cause of the low yield was the oxidation of xylose into the dead-end product xylonate by endogenous glucose dehydrogenase (Gcd). Subjecting the XylAB-expressingP. putida S12 to laboratory evolution yielded a strain that efficiently utilized xylose (yield, 52% [g CDW g xylose−1 ]) at a considerably improved growth rate (0.35 h−1 ). The high yield could be attributed in part to Gcd inactivity, whereas the improved growth rate may be connected to alterations in the primary metabolism. Surprisingly, without any further engineering, the evolvedd -xylose-utilizing strain metabolizedl -arabinose as efficiently asd -xylose. Furthermore, despite the loss of Gcd activity, the ability to utilize glucose was not affected. Thus, aP. putida S12-derived strain was obtained that efficiently utilizes the three main sugars present in lignocellulosic hydrolysate: glucose, xylose, and arabinose. This strain will form the basis for a platform host for the efficient production of biochemicals from renewable feedstock.