Production of ethanol from L-arabinose by Saccharomyces cerevisiae containing a fungal L-arabinose pathway.
The fungal pathway for L-arabinose catabolism converts L-arabinose to D-xylulose 5-phosphate in five steps. The intermediates are, in this order: L-arabinitol, L-xylulose, xylitol and D-xylulose. Only some of the genes for the corresponding enzymes were known. We have recently identified the two missing genes for L-arabinitol 4-dehydrogenase and L-xylulose reductase and shown that overexpression of all the genes of the pathway in Saccharomyces cerevisiae enables growth on L-arabinose. Under anaerobic conditions ethanol is produced from L-arabinose, but at a very low rate. The reasons for the low rate of L-arabinose fermentation are discussed.
Richard
Peter
P
VTT Biotechnology, P.O. Box 1500, Tietotie 2, Espoo 02044 VTT, Finland. peter.richard@vtt.fi
Verho
Ritva
R
Putkonen
Mikko
M
Londesborough
John
J
Penttilä
Merja
M
D000693:Anaerobiosis; D001089:Arabinose / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation / Q000502:physiology; D010084:Oxidation-Reduction; D010428:Pentosephosphates / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*
D010428:Pentosephosphates; D000431:Ethanol; C031625:xylulose-5-phosphate; D001089:Arabinose