title: Functional expression of xylose isomerase in flocculating industrial Saccharomyces cerevisiae strain for bioethanol production.
abstract: Saccharomyces cerevisiae strains with xylose isomerase (XI) pathway were constructed using a flocculating industrial strain (YC-8) as the host. Both strains expressing wild-type xylA (coding XI) from the fungus Orpinomyces sp. and the bacterium Prevotella ruminicola, respectively, showed better growth ability and fermentation capacity when using xylose as the sole sugar than most of the reported strains expressing XI. Codon optimization of both XIs did not improve the xylose fermentation ability of the strains. Adaption significantly increased XI activity resulting in improved growth and fermentation. The strains expressing codon-optimized XI showed a higher increase in xylose consumption and ethanol production compared to strains expressing wild XI. Among all strains, the adapted strain YCPA2E expressing XI from P. ruminicola showed the best performance in the fermentation of xylose to ethanol. After 48 h of fermentation, YCPA2E assimilated 16.95 g/L xylose and produced 6.98 g/L ethanol. These results indicate that YC-8 is a suitable host strain for XI expression, especially for the codon-optimized XI originating from P. ruminicola.
authors.affiliation: College of Light Industry, Textile and Food Engineering, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu 610065, China; College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu 610065, China.
authors.forename: Yun-Cheng
authors.initials: YC
authors.lastname: Li
authors.affiliation: College of Light Industry, Textile and Food Engineering, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu 610065, China.
authors.forename: Guo-Ying
authors.initials: GY
authors.lastname: Li
authors.affiliation: College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu 610065, China.
authors.forename: Min
authors.initials: M
authors.lastname: Gou
authors.affiliation: College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu 610065, China.
authors.forename: Zi-Yuan
authors.initials: ZY
authors.lastname: Xia
authors.affiliation: College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu 610065, China. Electronic address: tangyq@scu.edu.cn.
authors.forename: Yue-Qin
authors.initials: YQ
authors.lastname: Tang
authors.affiliation: College of Architecture and Environment, Sichuan University, No. 24, South Section 1, First Ring Road, Chengdu 610065, China.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kida
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D019149:Bioreactors; D003062:Codon / Q000235:genetics; D000431:Ethanol / Q000378:metabolism* / Q000600:supply & distribution; D005285:Fermentation; D005427:Flocculation; D020085:Neocallimastigales / Q000201:enzymology / Q000235:genetics; D045243:Prevotella ruminicola / Q000201:enzymology / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism
chemical_list: D003062:Codon; D000431:Ethanol; D014994:Xylose; D019747:Aldose-Ketose Isomerases; C023298:xylose isomerase
keywords: Bioethanol production; Industrial Saccharomyces cerevisiae; Strain adaption; Xylose fermentation; Xylose isomerase