Abstract
-
1.
The transport of guanine in autospores of light-dark synchronizedChlorella fusca was studied using radioactive guanine in the concentration range of 4 nM to 50 μM.
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2.
The transport system was constitutive, it had high specificity for the permeant, and theQ 10 value was in the range of 1.5 to 2.2. At concentrations lower than 0.2 μM the half saturating constant, S0.5 was 1 μM both for cells kept in dark and cells kept in light. At higher concentrations the S0.5 of darkened cells was about 0.23 μM, while that of illuminated cells was unchanged. Only above 0.2 μM guanine did illumination of the cells or addition of glucose increase the transport rate.
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3.
Guanine which had accumulated did not leak out at temperatures below 45°C or by treatment with 10 μM dinitrophenol, which completely inhibited transport. Furthermore, the accumulated guanine did not exchange with exogenous guanine.
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4.
The guanine accumulated, more than 105-fold over the external concentration, showing that the transport, was active.
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5.
The initial transport rate per cell revealed annual fluctuations.
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Abbreviations
- DNP:
-
2.4-dinitrophenol
- S0.5 :
-
the half saturating constant, i.e. the guanine concentration giving half maximum initial transport rateV/2
- TCA:
-
trichloroacetic acid
- TCAI:
-
trichloroacetic acid insoluble (fraction of the14C-labelled compounds in the cells)
- v D,v G andv L :
-
the initial transport rates measured in darkness, with glucose and with light, respectively
References
Amman, E. C. B., Lynch, V. H.: Purine metabolism by unicellular algae. II. Adenine, hypoxanthine, and xanthine degradation byChlorella pyrenoidosa. Biochim. biophys. Acta (Amst.)87, 370–379 (1964)
Bach, M. K., Fellig, J.: Stimulation of the respiration ofChlorella vulgaris by purines and purine analogues. Plant Physiol.35, 36–44 (1960)
Cowie, D. B., Bolton, E. T.: The use of metabolic pools of purine compound for nucleic acid synthesis in yeast. Biochim. biophys. Acta (Amst.)125, 292–298 (1957)
Kandler, O.: The effect of 2,4-dinitrophenol on respiration, oxydative assimilation, and photosynthesis inChlorella pyrenoidosa. Physiol. Plant.11, 675–684 (1958)
Knutsen, G.: Slide projector as an inexpensive automatic sample changer for radioactivity measurements. Lab. Pract.18, 164 (1969)
Knutsen, G.: Uptake of uracil by synchronousChlorella fusca. Physiol. Plant.27, 300–309 (1972)
Kuhl, A., Lorenzen, H.: Handling and culturing ofChlorella. In: Methods in cell physiology, D.M., Prescott, Ed., Vol. 1, Chapter 1, pp. 159–188. New York-London: Academic Press 1964
Kumamoto, J., Raison, J. K., Lyons, J. M.: Temperature “breaks” in Arrhenius plots: A thermodynamic consequence of a phase change. J. theoret. Biol.31, 47–51 (1971)
Lahou, J.: Métabolisme de la guanine-8-14C. Biochim. biophys. Acta (Amst.)27, 371–377 (1958)
Lien, T., Pettersen, R., Knntsen, G.: Effects of indole-3-acetic acid and gibberellin on synchronous cultures ofChlorella fusca. Physiol. Plant.24, 185–190 (1971)
Mangold, H. K.: Nucleinsäuren und Nucleotide. In: Dünnschicht-Chromatographie. Ein Laboratoriumshandbuch, E. Stahl, Ed., Chapter K. Berlin-Göttingen-Heidelberg: Springer 1962
Moberg, S., Knutsen, G., Goksoyr, J.: The “point of no return” concept in cell division. The effects of some metabolic inhibitors on synchronizedChlorella pyrenoidosa. Physiol. Plant.21, 390–400 (1968)
Pedersen, A., Knutsen, G.: Unpublished
Raa, J., Goksøyr, J.: Studies on the effects of the heartwood toxin β-thujaplicin on the metabolism of yeast. Physiol. Plant.18, 159–176 (1965)
Roush, A. H.: Crystallization of purines in the vacuole ofCandida utilis. Nature (Lond.)190, 449 (1961)
Vallée, M., Jeanjean, R.: Lesystème de transport de SO 2-4 chezChlorella pyrenoidosa et sa régulation. I. Etude cinétique, de la perméation. II. Recherches sur la régulation de l'entrée. Biochim. biophys. Acta (Amst.)150, 607–615 (1968)
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Pettersen, R., Knutsen, G. Uptake of guanine by synchronizedChlorella fusca . Arch. Microbiol. 96, 233–246 (1974). https://doi.org/10.1007/BF00590179
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DOI: https://doi.org/10.1007/BF00590179