Studies on marine occurring yeasts: Respiration, fermentation and salt tolerance

Norkrans, Birgitta

doi:10.1007/bf00425641

Cited by 47 publications

(28 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…cells grown in the presence of KCl (K-K and K-Na) had lower respiration rates, whether they had a high [K + ] i (K-K) or [Na + ] i (K-Na). These results are somewhat different from those reported by Norkrans (1968), who found only a slight stimulation of respiration in D. hansenii grown in the presence of 0·68  NaCl.…”

Section: Growth and Starvationcontrasting

confidence: 84%

Monovalent cation fluxes and physiological changes ofDebaryomyces hansenii grown at high concentrations of KCl and NaCl

Thomé‐Oritz

Peña

Ramı́rez

1998

Yeast

View full text Add to dashboard Cite

Debaryomyces hansenii showed an increased growth in the presence of either 1m KCl or 1m NaCl and a low acidification of the medium, higher for the cells grown in the presence of NaCl. These cells accumulated high concentrations of the cations, and showed a very fast capacity to exchange either Na+ or K+ for the opposite cation. They showed a rapid uptake of 86 Rb+ and 22 Na+ . 86 Rb+ transport was saturable, with Km and Vmax values higher for cells grown in 1m NaCl. 22 Na+ uptake showed a diffusion component, also higher for the cells grown with NaCl. Changes depended on growth conditions, and not on further incubation, which changed the internal ion concentration. K+ stimulated proton pumping produced a rapid extrusion of protons, and also a decrease of the membrane potential. Cells grown in 1m KCl showed a higher fermentation rate, but significantly lower respiratory capacity. ATP levels were higher in cells grown in the presence of NaCl; upon incubation with glucose, those grown in the presence of KCl reached values similar to the ones grown in the presence of NaCl. In both, the addition of KCl produced a transient decrease of the ATP levels. As to ion transport mechanisms, D. hansenii appears to have (a) an ATPase functioning as a proton pump, generating a membrane potential difference which drives K+ through a uniporter; (b) a K+ /H+ exchange system; and (c) a rapid cation/cation exchange system. Most interesting is that cells grown in different ionic environments change their studied capacities, which are not dependent on the cation content, but on differences in their genetic expression during growth. © 1998 John Wiley & Sons, Ltd.

show abstract

Section: Growth and Starvationcontrasting

confidence: 84%

Monovalent cation fluxes and physiological changes ofDebaryomyces hansenii grown at high concentrations of KCl and NaCl

Thomé‐Oritz

Peña

Ramı́rez

1998

Yeast

View full text Add to dashboard Cite

show abstract

“…Thus, a high respiratory capacity was shown not to favor a high tolerance to a sudden osmotic dehydration of S. cerevisiae. Respiration was shown earlier not to be the osmosensitive cellular function limiting growth under osmotic stress, since respiratory activity was found at salt concentrations that do not permit growth (22).…”

Section: Resultsmentioning

confidence: 99%

Microcalorimetric monitoring of growth of Saccharomyces cerevisiae: osmotolerance in relation to physiological state

1988

View full text Add to dashboard Cite

The importance of the physiological state of a culture of Saccharomyces cerevisiae for tolerance to sudden osmotic dehydration was studied, and it was investigated whether specific osmotolerance factors were demonstrable. The microcalorimeter was used to monitor growth, and different physiological states of the culture were selected and their osmotolerance was tested. In addition to cells in the stationary phase, cells from the transition phase between respirofermentative and respiratory catabolism were osmotolerant. S. cerevisiae exhibited ever-changing metabolism during batch growth on either glucose or ethanol as the carbon source. Instantaneous heat production per biomass formation (dQ/dX) and specific activity of sn-glycerol 3-phosphate dehydrogenase (GPDH) (EC 1.1.1.8) were shown to differ for different physiological states. Neither high respiratory activity nor low total cellular activity, nor factors involved in osmoregulation, i.e., intracellular glycerol or activity of GPDH, correlated with the osmotolerant phenotype.

show abstract

“…One of the problems associated with growth in highsalinity media is the establishment of a positive turgor pressure, which is considered to provide the mechanical force for expansion of the cell wall during growth (18,21 When D. hansenii was subjected to increased NaCl stress, there was a decrease of intracellular K+ and an increase of intracellular Na+ (27,28). However, the total salt level in the cells was not sufficient to balance the water potential of the medium; this is why there must be additional osmotically active solutes (28).…”

mentioning

confidence: 99%

“…When D. hansenii was subjected to increased NaCl stress, there was a decrease of intracellular K+ and an increase of intracellular Na+ (27,28). However, the total salt level in the cells was not sufficient to balance the water potential of the medium; this is why there must be additional osmotically active solutes (28).…”

mentioning

confidence: 99%

Osmoregulation of the salt-tolerant yeast Debaryomyces hansenii grown in a chemostat at different salinities

et al. 1990

View full text Add to dashboard Cite

The intracellular solute composition of the salt-tolerant yeast Debaryomyces hansenii was studied in glucose-limited chemostat cultures at different concentrations of NaCl (4 mM, 0.68 M, and 1.35 M). A strong positive correlation between the total intracellular polyol concentration (glycerol and arabinitol) and medium salinity was demonstrated. The intracellular polyol concentration'was sufficient to balance about 75% of the osmotic pressure of the medium in cultures with 0.68 and 1.35'M NaCl. The intracellular concentration of K+ and Na+, which at low external salinity gave a considerable contribution to the intracellular water potential, was only slightly enhanced with raised medium salinity. However, the ratio of intracellular K+ to Na+ decreased; but this decrease was less drastic in the cells than in the surrounding medium, i.e., the cells were able to select for K+ in favor of Na+. The turgor pressure, which was estimated on the basis of intracellular solute concentrations, was 2,200 kPa in cultures with 4 mM NaCl and decreased when the external salinity was raised, resulting in a value of about 500 kPa in cultures with 1.35 M NaCl. The maintenance of a positive'turgor pressure at high salinity was mainly due to an increased production and accumulation of glycerol.Microorganisms differ in their tolerances to osmotic stress, but in general yeasts and fungi are more tolerant than bacteria (6). Among yeasts, strains of Debaryomyces hansenii and Saccharomyces rouxii are highly osmotolerant and capable of growth in media containing up to about 4 M NaCl (26, 29), whereas Saccharomyces cerevisiae is limited by NaCl concentrations above 1.7 M (29).One of the problems associated with growth in highsalinity media is the establishment of a positive turgor pressure, which is considered to provide the mechanical force for expansion of the cell wall during growth (18,21 When D. hansenii was subjected to increased NaCl stress, there was a decrease of intracellular K+ and an increase of intracellular Na+ (27,28). However, the total salt level in the cells was not sufficient to balance the water potential of the medium; this is why there must be additional osmotically active solutes (28). Many eucaryotic microorganisms accumulate polyols intracellularly when exposed to osmotic stress (1,6,7,15,24), and in D. hansenii a positive correlation was demonstrated between the internal glycerol level and the salinity of the surrounding medium (1, 3). It was also observed that the tolerance for a sudden osmotic dehydration was better in cells having an increased amount of intracellular polyols (2). The two polyols produced and accumulated by D. hansenii are glycerol, which is the major internal solute in exponentially growing cells, and arabinitol, which predominates in stationary-phase cells (2). (8), and at the flow rate used an effective flowthrough cell volume of 0.39 ml was obtained. The culture was pumped at a rate of 80 ml/h from the growth vessel by a peristaltic pump (Microperpex LKB 2132) to a T connection outside the cal...

show abstract

Studies on marine occurring yeasts: Respiration, fermentation and salt tolerance

Cited by 47 publications

References 15 publications

Monovalent cation fluxes and physiological changes ofDebaryomyces hansenii grown at high concentrations of KCl and NaCl

Monovalent cation fluxes and physiological changes ofDebaryomyces hansenii grown at high concentrations of KCl and NaCl

Microcalorimetric monitoring of growth of Saccharomyces cerevisiae: osmotolerance in relation to physiological state

Osmoregulation of the salt-tolerant yeast Debaryomyces hansenii grown in a chemostat at different salinities

Contact Info

Product

Resources

About