EurekaMag.com logo
+ Site Statistics
References:
53,869,633
Abstracts:
29,686,251
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on LinkedInFollow on LinkedIn

+ Translate

Distinction between Hypoxanthine and Xanthine Transport in Chlamydomonas reinhardtii



Distinction between Hypoxanthine and Xanthine Transport in Chlamydomonas reinhardtii



Plant Physiology 95(1): 126-130



Chlamydomonas reinhardtii cells consumed hypoxanthine and xanthine by means of active systems which promoted purine intracellular accumulation against a high concentration gradient. Both uptake and accumulation were also observed in mutant strains lacking xanthine dehydrogenase activity. Xanthine and hypoxanthine uptake systems exhibited very similar Michaelis constants for transport and pH values, and both systems were induced by either hypoxanthine or xanthine. However, they differed greatly in the length of the lag phase before uptake induction, which was longer for hypoxanthine than for xanthine. Cells grown on ammonium and transferred to hypoxanthine media consumed xanthine before hypoxanthine, whereas cells transferred to xanthine media did not take up hypoxanthine until 2 hours after commencing xanthine consumption. Metabolic and photosynthetic inhibitors such as 2,4-dinitrophenol, 3-(3,4-dichlorophenyl)-1,1-dimethyl urea, and carbonylcyanide m-chlorophenylhydrazone inhibited to a different extent the hypoxanthine and xanthine uptake. Similarly, N-ethylmaleimide abolished xanthine uptake but slightly affected that of hypoxanthine. Hypoxhanthine consumption was inhibited by adenine and guanine whereas that of xanthine was inhibited only by urate. We conclude that hypoxanthine and xanthine in C. reinhardtii are taken up by different active transport systems which work independently of the intracellular enzymatic oxidation of these purines.

(PDF emailed within 0-6 h: $19.90)

Accession: 007218962

Download citation: RISBibTeXText

PMID: 16667938

DOI: 10.1104/pp.95.1.126



Related references

Energy-dependent transport of urate and xanthine in the unicellular green algae Chlamydomonas reinhardtii. NATO ASI Advanced Science Institutes Series Series A Life Sciences: 209-217 (157), 1988

Energy-dependent transport of urate and xanthine in the unicellular green alga Chlamydomonas reinhardtii. NATO ASI series: Series A: Life sciences57(157): 209-217, 1988

Hypoxanthine and xanthine transport through the blood-brain barrier in hypoxanthine phosphoribosyltransferase (HPRT) deficiency. Advances in Experimental Medicine and Biology 253a: 173-179, 1989

Isolation and characterization of xanthine dehydrogenase from chlamydomonas reinhardtii. Physiologia Plantarum 72(1): 101-107, 1988

Xanthine accumulation and vacuolization in Chlamydomonas reinhardtii cells. Protoplasma 186(1-2): 93-98, 1995

Purification and substrate inactivation of xanthine dehydrogenase from Chlamydomonas reinhardtii. Biochimica et Biophysica Acta 1117(2): 159-166, 1992

Occurrence of an NADH diaphorase activity associated with xanthine dehydrogenase in Chlamydomonas reinhardtii. FEMS microbiology letters Federation of European Microbiological Societies 43(3): 321-325, 1987

Ni induces the CRR1-dependent regulon revealing overlap and distinction between hypoxia and Cu deficiency responses in Chlamydomonas reinhardtii. Metallomics 8(7): 679-691, 2016

The effect of super mutagens on chlamydomonas reinhardtii part 2 relationship between mutability and size of chlamydomonas reinhardtii colony following exposure to n nitrosoalkyl urea derivatives. Acta Facultatis Rerum Naturalium Universitatis Comenianae Genetica 3: 45-54, 1972

Stable nuclear transformation of chlamydomonas reinhardtii by using a chlamydomonas reinhardtii gene as the selectable marker. Proceedings of the National Academy of Sciences of the United States of America 87(6): 2087-2091, 1990

Stable nuclear transformation of chlamydomonas reinhardtii using a chlamydomonas reinhardtii gene as the selectable marker. Journal of Cellular Biochemistry Supplement (13 PART D): 229, 1989

Effects of various agents on flagellar activity, flagellar autotomy and cell viability in four species of Chlamydomonas (Chlorophyta: Volvocales) Chlamydomonas dysosmos, Chlamydomonas moewusii, Chlamydomonas monoica, Chlamydomonas reinhardtii. Symposia of the Society for Experimental Biology: 5) 421-437, 1982

Potassium transport in Chlamydomonas reinhardtii: isolation and characterization of transport-deficient mutant strains. Planta 163(2): 208-213, 1985

Blue-light requirement for the biosynthesis of an NO2- transport system in the Chlamydomonas reinhardtii nitrate transport mutant S10. Plant cell and environment 22(9): 1169-1175, 1999

Transformation of chlamydomonas reinhardtii cw 15 with a plasmid containing chlamydomonas reinhardtii chloroplast sequences. Abstracts Of The Annual Meeting Of The American Society For Microbiology: 2, 1986