title: GRE2 from Scheffersomyces stipitis as an aldehyde reductase contributes tolerance to aldehyde inhibitors derived from lignocellulosic biomass.
abstract: Scheffersomyces (Pichia) stipitis is one of the most promising yeasts for industrial bioethanol production from lignocellulosic biomass. S. stipitis is able to in situ detoxify aldehyde inhibitors (such as furfural and 5-hydroxymethylfurfural (HMF)) to less toxic corresponding alcohols. However, the reduction enzymes involved in this reaction remain largely unknown. In this study, we reported that an uncharacterized open reading frame PICST_72153 (putative GRE2) from S. stipitis was highly induced in response to furfural and HMF stresses. Overexpression of this gene in Saccharomyces cerevisiae improved yeast tolerance to furfural and HMF. GRE2 was identified as an aldehyde reductase which can reduce furfural to FM with either NADH or NADPH as the co-factor and reduce HMF to FDM with NADPH as the co-factor. This enzyme can also reduce multiple aldehydes to their corresponding alcohols. Amino acid sequence analysis indicated that it is a member of the subclass "intermediate" of the short-chain dehydrogenase/reductase (SDR) superfamily. Although GRE2 from S. stipitis is similar to GRE2 from S. cerevisiae in a three-dimensional structure, some differences were predicted. GRE2 from S. stipitis forms loops at D133-E137 and T143-N145 locations with two α-helices at E154-K157 and E252-A254 locations, different GRE2 from S. cerevisiae with an α-helix at D133-E137 and a β-sheet at T143-N145 locations, and two loops at E154-K157 and E252-A254 locations. This research provided guidelines for the study of other SDR enzymes from S. stipitis and other yeasts on tolerant mechanisms to aldehyde inhibitors derived from lignocellulosic biomass.
authors.affiliation: Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Sichuan, 611130, People's Republic of China.
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Sichuan, 611130, People's Republic of China. mgen@sicau.edu.cn.
authors.forename: Menggen
authors.initials: M
authors.lastname: Ma
authors.affiliation: Bioenergy Research Unit, National Center for Agricultural Utilization Research, USDA-ARS, 1815 N University Street, Peoria, IL, 61604, USA. ZLewis.Liu@ars.usda.gov.
authors.forename: Z Lewis
authors.initials: ZL
authors.lastname: Liu
authors.affiliation: Institute of Natural Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Sichuan, 611130, People's Republic of China.
authors.forename: Quanju
authors.initials: Q
authors.lastname: Xiang
authors.affiliation: College of Landscape Architecture, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Sichuan, 611130, People's Republic of China.
authors.forename: Xi
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Plant Pathology, College of Agriculture, Sichuan Agricultural University, Wenjiang, Sichuan, 611130, People's Republic of China.
authors.forename: Na
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Sichuan, 611130, People's Republic of China. zhangxiaopingphd@126.com.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000449:Aldehyde Reductase / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D018533:Biomass; D000431:Ethanol / Q000378:metabolism*; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000378:metabolism*; D008031:Lignin / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D004718:Saccharomycetales / Q000235:genetics / Q000378:metabolism*
chemical_list: C036909:lignocellulose; D000431:Ethanol; C008046:5-hydroxymethylfurfural; D008031:Lignin; D005662:Furaldehyde; D000449:Aldehyde Reductase
keywords: Aldehyde inhibitors; Aldehyde reductase; Detoxification; Ethanol; Lignocellulosic biomass; Scheffersomyces stipitis