[Growth of a turbidostat culture of yeasts in the presence of a high concentration of compounds in a stationary mode and under osmotic shock conditions].
The growth of a turbidostat culture of the yeast strain Saccharomyces cerevisiae 14 was studied under steady-state conditions in the presence of high (1.2-3 M) concentrations of various soluble compounds and under transition conditions upon rapid concentration changes. The concentration was varied from the optimal one to that decreasing the growth rate two times and back to the optimal one. The effects of the following compounds on yeast growth in the steady-state regime were studied: glucose, sucrose, (NH4)2SO4, MgSO4, NaH2PO4, Na2SO4, KCl, NaCl, NH4Cl, MgCl2, and LiCl. To study transition processes, the following compounds were used: NH4Cl, NaH2PO4, MgCl2, MgSO4, (NH4)2SO4, KCl, and NaCl. When the NaCl concentration increased rapidly, the transition process was completed in the first generation. For the other compounds, this process lasted for several generations. The transition process was completed in the first generation in cultures previously inhibited by (NH4)2SO4 or NaH2PO4. Cell volume varied insignificantly among steady-state cultures grown under different conditions, except for those inhibited by NH4Cl or MgSO4. The level of glucose utilization increased with an increase in the concentrations of the compounds studied. The ratio of the duration of the juvenile developmental phases (prophase, metaphase) to the duration of the postjuvenile phases (anaphase, telophase) was constant over the concentration ranges tested. The inhibitory effect of a compound depended on its chemical nature rather than on its osmotic effect.
Kaliuzhin
V A
VA
Research Institute of Biology and Biophysics, Tomsk State University, Russia.
D019149:Bioreactors; D003470:Culture Media; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D009997:Osmotic Pressure; D012441:Saccharomyces cerevisiae / Q000254:growth & development* / Q000378:metabolism; D012492:Salts; D013395:Sucrose / Q000378:metabolism
D003470:Culture Media; D012492:Salts; D013395:Sucrose; D005947:Glucose