title: Effective improvement of the activity of membrane-bound alcohol dehydrogenase by overexpression of adhS in Gluconobacter oxydans.
abstract: OBJECTIVE
  To investigate the roles of adhS, which encodes the AdhS subunit of membrane-bound alcohol dehydrogenase (mADH) in Gluconobacter oxydans DSM2003, and to rationally improve mADH activity.
  
  
  RESULTS
  adhS was identified and overexpressed in G. oxydans DSM2003. Its overexpression promoted the AdhA subunit which serves as the primary dehydrogenase transfer from the periplasmic space to the periplasmic surface of the membrane thereby increasing the amount of active mADH and thus enhancing mADH activity up to 1.96-fold. The increased mADH activity significantly altered product selectivity (glyceric acid/dihydroxyacetone) during glycerol oxidation and increased the glyceric acid production by 7.6-fold. By comparison, overexpression of adhS and adhABS was equally effective in increasing the mADH activity and glyceric acid production.
  
  
  CONCLUSIONS
  adhS overexpression effectively improved mADH activity, indicating that for mADH, adhS might be a limiting component. The findings provide a guide for the efficient application of Gluconobacter spp. in hydroxy acid production.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Lulu
authors.initials: L
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China. jplin@ecust.edu.cn.
authors.forename: Jinping
authors.initials: J
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Dongzhi
authors.initials: D
authors.lastname: Wei
mesh_terms: D000426:Alcohol Dehydrogenase / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology*; D020600:Gluconobacter oxydans / Q000201:enzymology* / Q000378:metabolism; D005988:Glyceric Acids / Q000378:metabolism
chemical_list: D005988:Glyceric Acids; C042971:glyceric acid; D000426:Alcohol Dehydrogenase
keywords: Alcohol dehydrogenase; Dihydroxyaceton; Gluconobacter oxydans; Glyceric acid; Glycerol; Membrane-bound alcohol dehydrogenase