title: Improving xylitol production at elevated temperature with engineered Kluyveromyces marxianus through over-expressing transporters.
abstract: Three transporter genes including Kluyveromyces marxianus aquaglyceroporin gene (KmFPS1), Candida intermedia glucose/xylose facilitator gene (CiGXF1) or glucose/xylose symporter gene (CiGXS1) were over-expressed in K. marxianus YZJ017 to improve xylitol production at elevated temperatures. The xylitol production of YZJ074 that harbored CiGXF1 was improved to 147.62g/L in Erlenmeyer flask at 42°C. In fermenter, 99.29 and 149.60g/L xylitol were produced from 99.55 and 151.91g/L xylose with productivity of 4.14 and 3.40g/L/h respectively at 42°C. Even at 45°C, YZJ074 could produce 101.30g/L xylitol from 101.41g/L xylose with productivity of 2.81g/L/h. Using fed-batch fermentation through repeatedly adding non-sterilized substrate directly, YZJ074 could produce 312.05g/L xylitol which is the highest yield reported to date. The engineered strains YZJ074 which can produce xylitol at elevated temperatures is an excellent foundation for xylitol bioconversion.
authors.affiliation: School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China.
authors.forename: Jia
authors.initials: J
authors.lastname: Zhang
authors.affiliation: School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China.
authors.forename: Biao
authors.initials: B
authors.lastname: Zhang
authors.affiliation: School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Wang
authors.affiliation: School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Department of Biology and Biochemistry, University of Houston, Houston, TX 77004-5001, USA; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China.
authors.forename: Xiaolian
authors.initials: X
authors.lastname: Gao
authors.affiliation: School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China; Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China. Electronic address: hjiong@ustc.edu.cn.
authors.forename: Jiong
authors.initials: J
authors.lastname: Hong
mesh_terms: D061249:Batch Cell Culture Techniques; D019149:Bioreactors; D002175:Candida / Q000235:genetics; D005285:Fermentation; D005818:Genetic Engineering / Q000379:methods; D005947:Glucose / Q000378:metabolism; D007218:Industrial Microbiology / Q000295:instrumentation / Q000379:methods*; D007716:Kluyveromyces / Q000235:genetics* / Q000378:metabolism*; D009004:Monosaccharide Transport Proteins / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013696:Temperature; D014993:Xylitol / Q000096:biosynthesis*; D014994:Xylose / Q000378:metabolism
chemical_list: D009004:Monosaccharide Transport Proteins; D011994:Recombinant Proteins; D014994:Xylose; D005947:Glucose; D014993:Xylitol
keywords: CiGXF1; Elevated temperature; K. marxianus; Xylitol; Xylose