Premium
Transmembrane distribution of substrate and product during the bioreduction of acetophenone with resting cells of Saccharomyces cerevisiae
Author(s) -
Zhao Yujun,
DeLancey George B.
Publication year - 1999
Publication title -
biotechnology and bioengineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.136
H-Index - 189
eISSN - 1097-0290
pISSN - 0006-3592
DOI - 10.1002/(sici)1097-0290(19990820)64:4<434::aid-bit6>3.0.co;2-1
Subject(s) - acetophenone , chemistry , extracellular , intracellular , partition coefficient , chromatography , substrate (aquarium) , biochemistry , biology , catalysis , ecology
The average volumetric intracellular concentrations of acetophenone and phenethyl alcohol were determined during the bioreduction of acetophenone using resting cells of Saccharomyces cerevisiae in aqueous solutions at 30°C. The behavior of their distribution coefficients (ratio of intracellular to extracellular concentrations) during the bioreduction process was evaluated with different cell preparation and extracellular conditions. The distribution coefficient of acetophenone was found to be in the range of 2.3–4.0. The distribution coefficient of phenethyl alcohol was found to be in the range of 1.3–1.8. Both the distribution coefficients were correlated significantly only with the physiological state of the resting cells as reflected by the relative cell mass (0.65–1.09). The correlation is approximately linear with the largest slope for the toxic reagent, acetophenone. No significant effects on the distribution coefficients were experimentally observed or were present in a regression analysis for the concentrations of acetophenone (0–0.30% v/v), phenethyl alcohol (0–0.20% v/v), ethanol (1.60–2.25% v/v), the extracellular pH (pH 2–7), or the presence of the salts: KCl, KH 2 PO 4 , MgSO 4 , NaCl, and CaCl 2 (each 0–0.1 M ) in the medium. Different cell initialization times (0–6 days) and initialization conditions were also included. © 1999 John Wiley & Sons, Inc. Biotechnol Bioeng 64: 434–441, 1999.