Characterization of new polyol/H+ symporters in Debaryomyces hansenii

PLoS One. 2014 Feb 4;9(2):e88180. doi: 10.1371/journal.pone.0088180. eCollection 2014.

Abstract

Debaryomyces hansenii is a halotolerant yeast that produces and assimilates a wide variety of polyols. In this work we evaluate polyol transport in D. hansenii CBS 767, detecting the occurrence of polyol/H(+) (and sugar/H(+)) symporter activity, through the transient extracellular alkalinization of unbuffered starved cell suspensions. From the D. hansenii genome database, we selected nine ORFs encoding putative transporter proteins to clone in a centromeric plasmid with C-terminal GFP tagging and screened for polyol/H(+) symporters by heterologous expression in Saccharomyces cerevisiae. Five distinct D. hansenii polyol/H(+) symporters were identified and characterized, with different specificities and affinities for polyols, namely one glycerol-specific (DhStl1), one D-galactitol-specific (DhSgl1, Symporter galactitol/H(+) 1), one D-(+)-chiro-inositol-specific (DhSyi1, Symporter D-(+)-chiro-inositol/H(+) 1), one for D-sorbitol/D-mannitol/ribitol/D-arabitol/D-galactitol (DhSyl1, Symporter Polyols 1) and another for D-sorbitol/D-mannitol/ribitol/D-arabitol (DhSyl2, Symporter Polyols 2). This work contributed to the annotation of new yeast polyol transporters, including two specific for uncommon substrates as galactitol and D-(+)-chiro-inositol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Transport / physiology*
  • Debaryomyces / metabolism*
  • Galactose / analogs & derivatives
  • Galactose / metabolism
  • Glycerol / metabolism
  • Hydrogen / metabolism*
  • Inositol / metabolism
  • Mannitol / metabolism
  • Polymers / metabolism*
  • Saccharomyces cerevisiae / metabolism
  • Sorbitol / metabolism
  • Sugar Alcohols / metabolism
  • Symporters / metabolism*

Substances

  • Polymers
  • Sugar Alcohols
  • Symporters
  • polyol
  • galactal
  • Mannitol
  • Inositol
  • Sorbitol
  • Hydrogen
  • Glycerol
  • Galactose
  • arabitol

Grants and funding

This work was supported by Fundação para a Ciência e Tecnologia, Portugal (Post-Doctoral fellowships SFRH/BPD/41812/2007 to M.J.L. and SFRH/BPD/85143/2012 to C.P., PhD fellowship SFRH/BD/45930/2008 to A.M., FCT Ciência 2007 and Research Project “To promote xylitol release to improve bioethanol business” (PTDC/AGR-CFL/71792/2006)). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.