Quantitative aerobic physiology of the yeast Dekkera bruxellensis, a major contaminant in bioethanol production plants.
Dekkera bruxellensis has been described as the major contaminant yeast of industrial ethanol production, although little is known about its physiology. The aim of this study was to investigate the growth of this yeast in diverse carbon sources and involved conducting shake-flask and glucose- or sucrose-limited chemostats experiments, and from the chemostat data, the stoichiometry of biomass formation during aerobic growth was established. As a result of the shake-flask experiments with hexoses or disaccharides, the specific growth rates were calculated, and a different behavior in rich and mineral medium was observed concerning to profile of acetate and ethanol production. In C-limited chemostats conditions, the metabolism of this yeast was completely respiratory, and the biomass yields reached values of 0.62 gDW gS(-1) . In addition, glucose pulses were applied to the glucose- or sucrose-limited chemostats. These results showed that D. bruxellensis has a short-term Crabtree effect. While the glucose pulse was at the sucrose-limited chemostat, sucrose accumulated at the reactor, indicating the presence of a glucose repression mechanism in D. bruxellensis.
Interdepartmental Research Group in Metabolic Engineering, Federal University of Pernambuco, Recife, Brazil.
Fernanda Cristina Bezerra
FC
Leite
Thiago Olitta
TO
Basso
Will de Barros
Wde B
Pita
Andreas Karoly
AK
Gombert
Diogo Ardaillon
DA
Simões
Marcos Antonio
MA
de Morais
D000085:Acetates / Q000378:metabolism; D000332:Aerobiosis; D018533:Biomass; D002244:Carbon / Q000378:metabolism*; D019069:Cell Respiration; D003470:Culture Media; D055167:Dekkera / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005656:Fungal Proteins / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D007218:Industrial Microbiology; D010100:Oxygen / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000737:chemistry*; D013395:Sucrose / Q000378:metabolism; D043324:beta-Fructofuranosidase / Q000378:metabolism
D000085:Acetates; D003470:Culture Media; D005656:Fungal Proteins; D000431:Ethanol; D013395:Sucrose; D002244:Carbon; D043324:beta-Fructofuranosidase; D005947:Glucose; D010100:Oxygen