scholarly journals Nucleoside uptake inVibrio choleraeand its role in the transition fitness from host to environment

2015 ◽  
Vol 99 (3) ◽  
pp. 470-483 ◽  
Author(s):  
Tanja Gumpenberger ◽  
Dina Vorkapic ◽  
Franz G. Zingl ◽  
Katharina Pressler ◽  
Stefanie Lackner ◽  
...  
Keyword(s):  
Nucleoside Uptake

The specificity of purine base and nucleoside uptake in promastigotes ofLeishmania braziliensis panamensis

Parasitology ◽  
1982 ◽  
Vol 85 (2) ◽  
pp. 271-282 ◽  
Author(s):  
B. D. Hansen ◽  
J. Perez-Arbelo ◽  
J. F. Walkony ◽  
L. D. Hendricks
Keyword(s):  
Competitive Interactions ◽  
Leishmania Braziliensis ◽  
Purine Base ◽  
Purine Bases ◽  
Uptake Rates ◽  
Nucleoside Uptake ◽  
And Diffusion

SUMMARYPromastigotes ofLeishmania braziliensis panamensisabsorbed the purines adenine, hypoxanthine, adenosine and inosine by a combination of diffusion and mediated components. When the uptake rates for these substrates were corrected for diffusion and compared, the purine bases adenine and hypoxanthine were transported at a significantly slower rate than the purine nucleosides adenosine and inosine. Competitive interactions among those purines tested confirmed the presence of mediated and diffusion components and suggested that three transport loci may be operating (Fig. 6). The first transport locus, designated Locus 1, transported inosine, Locus 2, the purine bases hypoxanthine and adenine and Locus 3, adenosine. In addition, adenine and hypoxanthine inhibited the uptake of one another competitively. A comparison of Kivalues derived from double reciprocal plots of labelled hypoxanthine and adenine uptake in the presence of the unlabelled substrates as inhibitors suggested that adenine has a greater affinity for the transport locus.

Comparison of Clostridium difficile Detection by Monolayer and by Inhibition of Nucleoside Uptake

1987 ◽  
Vol 87 (2) ◽  
pp. 270-272
Author(s):  
Joseph E. Fuhr ◽  
Diane J. Trent ◽  
I. Reid Collmann
Keyword(s):  
Clostridium Difficile ◽  
Nucleoside Uptake

Passive diffusion of nucleosides into Micrococcus sodonensis membrane vesicles

1980 ◽  
Vol 58 (6) ◽  
pp. 457-460 ◽  
Author(s):  
M. A. Pickard
Keyword(s):  
Energy Source ◽  
Membrane Vesicles ◽  
Passive Diffusion ◽  
Membrane Bound ◽  
Nucleoside Uptake ◽  
Membrane Bound Enzymes ◽  
Isolated Membrane Vesicles

Nucleoside entry into isolated membrane vesicles of Micrococcus sodonensis (luteus) was studied using 14C-labelled nucleosides: adenosine, inosine, cytidine, uridine, guanosine, and thymidine. All nucleosides were recovered unmetabolized from the vesicles except adenosine and cytidine which were partly deaminated by membrane-bound enzymes. Vesicle preparations actively transported proline but no energy source was found capable of supporting concentrative nucleoside uptake. The entry of nucleosides into M. sodonensis vesicles was not saturable, nor was there competition between the nucleosides studied for entry. It was concluded that nucleoside entry into M. sodonensis vesicles occurs by passive diffusion.

Purine Base and Nucleoside Uptake in Plasmodium berghei and Host Erythrocytes

1980 ◽  
Vol 66 (2) ◽  
pp. 205 ◽  
Author(s):  
Brian D. Hansen ◽  
H. Kenneth Sleeman ◽  
Peter W. Pappas
Keyword(s):  
Plasmodium Berghei ◽  
Purine Base ◽  
Nucleoside Uptake

scholarly journals Regulation of proliferation of LLC-MK2 cells by nucleosides and nucleotides: the role of ecto-enzymes

1996 ◽  
Vol 316 (2) ◽  
pp. 551-557 ◽  
Author(s):  
Raf LEMMENS ◽  
Luc VANDUFFEL ◽  
Henri TEUCHY ◽  
Ognjen CULIC
Keyword(s):  
Cell Proliferation ◽  
Adenine Nucleotides ◽  
Inhibitory Effect ◽  
Pyrimidine Nucleoside ◽  
Purine Nucleotides ◽  
Pyrimidine Nucleotides ◽  
Nucleotides And Nucleosides ◽  
Nucleoside Uptake ◽  
Stimulate Cell Proliferation

1. Using the incorporation of [methyl-3H]thymidine as a proliferation marker, the effects of various nucleosides and nucleotides on endothelial LLC-MK2 cells were studied. We found that ATP, ADP, AMP and adenosine in concentrations of 10 μM or higher stimulate the proliferation of these cells. 2. Inhibition of ecto-ATPase (EC 3.6.1.15), 5´-nucleotidase (EC 3.1.3.5) or alkaline phosphatase (EC 3.1.3.1) significantly diminished the stimulatory effect of ATP, indicating that the effect is primarily caused by adenosine and not by adenine nucleotides. Also, the effect depends only on extracellular nucleosides, since inhibition of nucleoside uptake by dipyridamole has no influence on proliferation. 3. Other purine nucleotides and nucleosides (ITP, GTP, inosine and guanosine) also stimulate cell proliferation, while pyrimidine nucleotides and nucleosides (CTP, UTP, cytidine and uridine) inhibit proliferation. Furthermore, the simultaneous presence of adenosine and any of the other purine nucleosides is not entirely additive in its effect on cell proliferation. At the same time any pyrimidine nucleoside, when added together with adenosine, has the same inhibitory effect as the pyrimidine nucleoside alone. 4. Apparently these proliferative effects are neither caused by any pharmacologically known P1-purinoceptor, nor are they mediated by cyclic AMP, cyclic GMP, or D-myo-inositol 1,4,5-trisphosphate as second messenger, nor by extracellular Ca2+. 5. Therefore, we conclude that various purine and pyrimidine nucleosides can influence the proliferation of LLC-MK2 cells by acting on putative purinergic and pyrimidinergic receptors not previously described.

scholarly journals Pyrimidine Nucleoside Uptake by Petunia Pollen

1985 ◽  
Vol 79 (3) ◽  
pp. 801-805 ◽  
Author(s):  
Rajender K. Kamboj ◽  
John F. Jackson
Keyword(s):  
Pyrimidine Nucleoside ◽  
Nucleoside Uptake
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