Overexpression of alcohol dehydrogenase or pyruvate decarboxylase improves growth of hairy roots at reduced oxygen concentrations.
Overexpression of Arabidopsis thaliana genes for the fermentation enzymes, alcohol dehydrogenase and pyruvate decarboxylase, improved the tolerance of A. thaliana hairy roots to low oxygen conditions. Whereas the specific growth rate of untransformed hairy roots in shake flasks and in a multiple-tube recirculation bioreactor declined significantly with decreasing oxygen tension down to 25% air saturation, growth of the transformant root lines was maintained at rates similar to those achieved with full aeration. This work demonstrates that altering the expression of selected genes involved in anaerobic metabolism can alleviate the problems of oxygen deficiency in hairy root cultures caused by poor mixing and mass transfer conditions.
Shiao
Tien-li
TL
Department of Biotechnology, University of New South Wales, Sydney NSW 2052, Australia.
Ellis
Marc H
MH
Dolferus
Rudy
R
Dennis
Elizabeth S
ES
Doran
Pauline M
PM
D000426:Alcohol Dehydrogenase / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005786:Gene Expression Regulation; D000860:Hypoxia / Q000378:metabolism; D010101:Oxygen Consumption; D018517:Plant Roots / Q000201:enzymology / Q000235:genetics / Q000254:growth & development*; D030821:Plants, Genetically Modified / Q000254:growth & development / Q000502:physiology*; D011767:Pyruvate Decarboxylase / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D014170:Transformation, Genetic; D015854:Up-Regulation
D000426:Alcohol Dehydrogenase; D011767:Pyruvate Decarboxylase