scholarly journals The Influence of Erythrocyte Maturity on Ion Transport and Membrane Lipid Composition in the Rat

2016 ◽  
pp. 91-99 ◽  
Author(s):  
M. VOKURKOVÁ ◽  
H. RAUCHOVÁ ◽  
Z. DOBEŠOVÁ ◽  
J. LOUKOTOVÁ ◽  
O. NOVÁKOVÁ ◽  
...  
Keyword(s):  
Ion Transport ◽  
Lipid Composition ◽  
Membrane Lipid ◽  
Phospholipid Content ◽  
Hemoglobin Content ◽  
Mature Erythrocyte ◽  
Membrane Lipid Composition ◽  
Significant Relationships ◽  
Pump Activity ◽  
Immature Cells

Significant relationships between ion transport and membrane lipid composition (cholesterol, total phospholipids and sphingomyelins) were found in erythrocytes of salt hypertensive Dahl rats. In these animals mean cellular hemoglobin content correlated negatively with Na+-K+ pump activity and Na+ leak but positively with Na+-K+ cotransport activity. Immature erythrocytes exhibit lower mean cellular hemoglobin content (MCHC) than mature ones. The aim of the present study was to find a relationship between erythrocyte maturity, membrane lipid composition and ion transport activity in Wistar rats aged three months which were subjected to repeated hemorrhage (blood loss 2 ml/day for 6 days) to enrich circulating erythrocytes with immature forms. Immature and mature erythrocyte fractions in control and hemorrhaged rats were separated by repeated centrifugation. Hemorrhaged rats had increased number of reticulocytes but reduced hematocrit and MCHC compared to control rats. Immature erythrocytes of hemorrhaged rats differed from mature ones of control animals by elevated Na+-K+ pump activity, reduced Na+-K+ cotransport activity and increased Rb+ leak. These ion transport changes in immature erythrocytes were accompanied by higher concentration of total phospholipids in their cell membranes. Membrane phospholipid content correlated positively with Na+-K+ pump activity and cation leaks but negatively with Na+-K+ cotransport activity. Moreover, they were also negatively related with MCHC which correlated negatively with Na+-K+ pump activity and Rb+ leak but positively with Na+-K+ cotransport activity. Thus certain abnormalities of erythrocyte ion transport and membrane lipid composition detected in hypertensive animals might be caused by higher incidence of immature cells.

Erythrocyte ion transport and membrane lipid composition in young and adult rats with NO-deficient hypertension

Life Sciences ◽  
2003 ◽  
Vol 73 (13) ◽  
pp. 1637-1644 ◽  
Author(s):  
Martina Vokurková ◽  
Zdena Dobešová ◽  
Olga Pecháňová ◽  
Jaroslav Kuneš ◽  
Josef Zicha
Keyword(s):  
Ion Transport ◽  
Lipid Composition ◽  
Membrane Lipid ◽  
Adult Rats ◽  
Membrane Lipid Composition

scholarly journals Membrane Lipid Composition of the Moderately Thermophilic Ammonia-Oxidizing Archaeon “Candidatus Nitrosotenuis uzonensis” at Different Growth Temperatures

2019 ◽  
Vol 85 (20) ◽  
Author(s):  
Nicole J. Bale ◽  
Marton Palatinszky ◽  
W. Irene C. Rijpstra ◽  
Craig W. Herbold ◽  
Michael Wagner ◽  
...  
Keyword(s):  
Lipid Composition ◽  
Strong Influence ◽  
Thermal Spring ◽  
Membrane Lipid ◽  
Effect Of Temperature ◽  
Environmental Niche ◽  
Membrane Lipid Composition ◽  
Moderately Thermophilic ◽  
Wide Range ◽  
Membrane Spanning

ABSTRACT “Candidatus Nitrosotenuis uzonensis” is the only cultured moderately thermophilic member of the thaumarchaeotal order Nitrosopumilales (NP) that contains many mesophilic marine strains. We examined its membrane lipid composition at different growth temperatures (37°C, 46°C, and 50°C). Its lipids were all membrane-spanning glycerol dialkyl glycerol tetraethers (GDGTs), with 0 to 4 cyclopentane moieties. Crenarchaeol (cren), the characteristic thaumarchaeotal GDGT, and its isomer (crenʹ) were present in high abundance (30 to 70%). The GDGT polar headgroups were mono-, di-, and trihexoses and hexose/phosphohexose. The ratio of glycolipid to phospholipid GDGTs was highest in the cultures grown at 50°C. With increasing growth temperatures, the relative contributions of cren and crenʹ increased, while those of GDGT-0 to GDGT-4 (including isomers) decreased. TEX86 (tetraether index of tetraethers consisting of 86 carbons)-derived temperatures were much lower than the actual growth temperatures, further demonstrating that TEX86 does not accurately reflect the membrane lipid adaptation of thermophilic Thaumarchaeota. As the temperature increased, specific GDGTs changed relative to their isomers, possibly representing temperature adaption-induced changes in cyclopentane ring stereochemistry. Comparison of a wide range of thaumarchaeotal core lipid compositions revealed that the “Ca. Nitrosotenuis uzonensis” cultures clustered separately from other members of the NP order and the Nitrososphaerales (NS) order. While phylogeny generally seems to have a strong influence on GDGT distribution, our analysis of “Ca. Nitrosotenuis uzonensis” demonstrates that its terrestrial, higher-temperature niche has led to a lipid composition that clearly differentiates it from other NP members and that this difference is mostly driven by its high crenʹ content. IMPORTANCE For Thaumarchaeota, the ratio of their glycerol dialkyl glycerol tetraether (GDGT) lipids depends on growth temperature, a premise that forms the basis of the widely applied TEX86 paleotemperature proxy. A thorough understanding of which GDGTs are produced by which Thaumarchaeota and what the effect of temperature is on their GDGT composition is essential for constraining the TEX86 proxy. “Ca. Nitrosotenuis uzonensis” is a moderately thermophilic thaumarchaeote enriched from a thermal spring, setting it apart in its environmental niche from the other marine mesophilic members of its order. Indeed, we found that the GDGT composition of “Ca. Nitrosotenuis uzonensis” cultures was distinct from those of other members of its order and was more similar to those of other thermophilic, terrestrial Thaumarchaeota. This suggests that while phylogeny has a strong influence on GDGT distribution, the environmental niche that a thaumarchaeote inhabits also shapes its GDGT composition.

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