Abstract
The intracellular pH of the halotolerant green algae Dunaliella tertiolecta, was determined by the distribution of 5,5-dimethyl-2(14C)-oxalolidine-2,5-dione (DMO) between the cell and the surrounding medium. 5,5-dimethyl-2(14C)oxalolidine-2,4-dione was not metabolized by the algal cells. The intracellular pH of Dunaliella tertiolecta was 6.8 in the dark and 7.4 in the light. During a salt stress, after two hours, the intracellular pH was increased by 0.2 pH units in both light and dark. The salt stressed cells maintained a constant pH of about 7.5 over the pH range of 6.5 to 8.5. Because of the relatively low permeability coefficient of the plasma membrane for DMO, this technique does not permit rapid pH determinations during the induction period after a salt stress. The magnitude of the salt induced pH changes measured 2 h after the salt stress implies a minor importance of this alkalization in this time range, but does not exclude a larger importance of pH changes for osmoregulation during the induction period.
Similar content being viewed by others
Abbreviations
- Chl:
-
chlorophyll
- DMO:
-
5,5-dimethyl-2(14C)oxalolidine-2,4-dione
- PCV:
-
packed cell volume
- SDS:
-
sodium dodecyl sulfate
References
Badger MR, Kaplan A, Berry JA (1977) The internal CO2 pool of Chlamydomonas reinhardtii: Response to external CO2. Carnegie Inst Yearb 76:362–366
Borowitzka, LJ, Brown AD (1974) The salt relations of marine and halophilic species of the unicellular alga, Dunaliella: The role of glycerol as a compatible solute. Arch Microbiol 96:37–52
Bown AW (1985) CO2 and intracellular pH. Plant, Cell Environ 8:459–465
Brown AD (1978) Compatible solutes and extreme water stress in eukaryotic microorganisms. Adv Microbial Physiol 17:181–242
Coleman JR, Colman B (1981) Inorganic carbon accumulation and photosynthesis in a blue-green alga as a function of external pH. Plant Physiol 67:917–921
DeMichelis MI, Raven JA, Jayasuriya HD (1979) Measurement of cytoplasmic pH by the DMO technique in Hydrodictyon africanum. J Exp Bot 30:681–695
Ehrenfeld J, Cousin JL (1984) Ionic regulation of the unicellular green alga Dunaliella tertiolecta: Response to hyperosmotic shock. J Memb Biol 77:45–55
Falkner G, Horner F, Werdan K, Heldt HW (1976) pH changes in the cytoplasm of the blue-green alga Anacystis nidulans caused by light-dependent proton flux into the thylakoid space. Plant Physiol 58:717–718
Gilmour DJ; Kaaden R, Gimmler H (1985) Vanadate inhibition of ATPases of Dunaliella parva in vitro and in vivo. J Plant Physiol 118:111–126
Gimmler H, Hartung W (1988) Low permeability of the plasma membrane of Dunaliella parva for solutes. J Plant Physiol 133:165–172
Gimmler H, Schirling R (1978) Cation permeability of the plasmalemma of the halotolerant alga Dunaliella parva. II. Cation content and glycerol concentration of the cell as dependent upon external concentration. J Plant Physiol 87:435–444
Gimmler H, Schirling R, Tobler U (1977) Cation permeability of the plasmalemma of the halotolerant alga Dunaliella parva. I. Cation induced osmotic volume changes. J Plant Physiol 83:145–148
Gimmler H, Kugel H, Leibfritz D, Mayer A (1988) Cytoplasmic pH of Dunaliella parva and Dunaliella acidophila as monitored by in vivo 31P-NMR spectroscopy and the DMO method. Physiol Plant 74:521–530
Ginzburg M (1981) Measurements of ion concentration in Dunaliella parva subjected to hypertonic stress. J Exp Bot 32:333–340
Heldt HW (1980) Measurement of metabolite movements across the envelope and of the pH in the stroma and the thylakoid space in intact chloroplasts. Meth Enzymol 69:604–613
Heldt HW, Werdan R, Milovancev M, Geller G (1973) Alkalization of the chloroplast stroma caused by light-dependent proton flux into the thylakoid space. Biochem Biophys Acta 314:224–241
Johnson MK, Johnson EJ, MacElroy RD, Speer HL (1986) Effects of salts on the halophilic alga Dunaliella viridis. J Bacteriol 95:1461–1468
Lane AE, Burris JE (1981) Effects of environmental pH on the internal pH of Chlorella pyrenoidosa, Scenedesmus quadricauda, and Euglena mutabilis. Plant Physiol 68:439–442
Lerner HR, Avron M (1977) Dihydroxyacetone kinase activity in Dunaliella parva. Plant Physiol 59:15–17
McKinney G (1941) Absorption of light by chlorophyll solutions. J Biol Chem 140:313–322
Moroney, JV, Tolbert NE (1985) Inorganic carbon uptake by Chlamydomonas reinhardtii. Plant Physiol 77:253–258
Raven JA, Smith FA (1978) Effect of temperature and external pH on the cytoplasmic pH of Chara corallina. J Exp Bot 29:853–866
Sianoudis J, Küsel AC, Grimme LH, Leibfritz D (1987) The cytoplasmic pH in photosynthesizing cells of the green alga Chlorella fusca, measured by P-31 NMR spectroscopy. Arch Microbiol 147:25–29
Smith FA (1986) Short-term measurement of the cytoplasmic pH of Chara corallina derived from the intracellular equilibration of 5,5-dimethyloxazolidine-2,4-dione (DMO). J Exp Bot 37:1733–1745
Sussman I, Avron M (1981) Characterization and partial purification of DL-glycerol-1-phosphatase from Dunaliella salina. Biochem Biophys Acta 661:199–204
Walker NA, Smith FA (1975) Intracellular pH in Chara corallina measured by DMO distribution. Plant Sci Lett 4:125–132
Wegmann K (1979) Biochemical adaptation of Dunaliella tertiolecta to salinity and temperature changes. Ber Dt Bot Ges 92:43–52
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Goyal, A., Gimmler, H. Osmoregulation in Dunaliella tertiolecta: effects of salt stress, and the external pH on the internal pH. Arch. Microbiol. 152, 138–142 (1989). https://doi.org/10.1007/BF00456091
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00456091