Ferric and cupric reductase activities by iron-limited cells of the green alga Chlorella kessleri: quantification via oxygen electrode

AbstractMembrane lipid remodeling contributes to the environmental acclimation of plants. In the green lineage, a betaine lipid, diacylglyceryl-N,N,N-trimethylhomoserine (DGTS), is included exclusively among green algae and nonflowering plants. Here, we show that the green alga Chlorella kessleri synthesizes DGTS under phosphorus-deficient conditions through the eukaryotic pathway via the ER. Simultaneously, phosphatidylcholine and phosphatidylethanolamine, which are similar to DGTS in their zwitterionic properties, are almost completely degraded to release 18.1% cellular phosphorus, and to provide diacylglycerol moieties for a part of DGTS synthesis. This lipid remodeling system that substitutes DGTS for extrachloroplast phospholipids to lower the P-quota operates through the expression induction of the BTA1 gene. Investigation of this lipid remodeling system is necessary in a wide range of lower green plants for a comprehensive understanding of their phosphorus deficiency acclimation strategies.

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Gene cloning, sequence analysis, and expression profiles of a novel β-ring carotenoid hydroxylase gene from the photoheterotrophic green alga Chlorella kessleri

Molecular Biology Reports ◽

10.1007/s11033-014-3524-8 ◽

2014 ◽

Vol 41 (11) ◽

pp. 7103-7113 ◽

Cited By ~ 2

Author(s):

Xiaona Yu ◽

Hongli Cui ◽

Yulin Cui ◽

Yan Wang ◽

Xueqin Li ◽

...

Keyword(s):

Sequence Analysis ◽

Gene Cloning ◽

Green Alga ◽

Expression Profiles ◽

Chlorella Kessleri ◽

Hydroxylase Gene ◽

Green Alga Chlorella ◽

Carotenoid Hydroxylase

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Optimization of seawater-based triacylglycerol accumulation in a freshwater green alga, Chlorella kessleri , through simultaneous imposition of lowered-temperature and enhanced-light intensity

Algal Research ◽

10.1016/j.algal.2017.10.016 ◽

2017 ◽

Vol 28 ◽

pp. 100-107 ◽

Cited By ~ 5

Author(s):

Taihei Hayashi ◽

Rie Otaki ◽

Kazuho Hirai ◽

Mikio Tsuzuki ◽

Norihiro Sato

Keyword(s):

Light Intensity ◽

Green Alga ◽

Chlorella Kessleri ◽

Green Alga Chlorella ◽

Triacylglycerol Accumulation

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Active transport of CO2 and bicarbonate is induced in response to external CO2 concentration in the green alga Chlorella kessleri

Journal of Experimental Botany ◽

10.1093/jexbot/51.349.1341 ◽

2000 ◽

Vol 51 (349) ◽

pp. 1341-1348 ◽

Cited By ~ 18

Author(s):

G. G. Bozzo

Keyword(s):

Active Transport ◽

Green Alga ◽

Co2 Concentration ◽

Chlorella Kessleri ◽

Green Alga Chlorella

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High stability ferric chelates result in decreased iron uptake by the green alga Chlorella kessleri owing to decreased ferric reductase activity and chelation of ferrous iron

Botany ◽

10.1139/b09-063 ◽

2009 ◽

Vol 87 (10) ◽

pp. 922-931 ◽

Cited By ~ 9

Author(s):

Harold G. Weger ◽

Jackie Lam ◽

Nikki L. Wirtz ◽

Crystal N. Walker ◽

Ron G. Treble

Keyword(s):

Stability Constant ◽

Green Alga ◽

Iron Uptake ◽

High Stability ◽

Reductase Activity ◽

Iron Acquisition ◽

Free Form ◽

Ferric Reductase ◽

Chlorella Kessleri ◽

Green Alga Chlorella

Cells of the green alga Chlorella kessleri Fott et Nováková use a reductive mechanism for iron acquisition. Iron-limited cells acquired iron more rapidly from a chelator with a lower stability constant for Fe3+ (hydroxyethylethylenediaminetriacetic acid (HEDTA)) than from a chelator with a higher stability constant (N,N′-di[2-hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (HBED)). Furthermore, iron uptake rates decreased with increasing chelator concentrations at constant iron concentration. The negative effects of elevated HBED levels on iron uptake could be partly alleviated by the addition of Ga3+, which suggests that iron-free chelator has a negative effect on iron acquisition by competing for Fe2+ with the ferrous transport system. Furthermore, ferric reductase activity progressively decreased with increasing concentrations of both chelators (in the iron-free form). This effect was not alleviated by Ga3+ addition and was apparently caused by the direct inhibition of the reductase. Overall, we conclude that chelators with high stability constants for Fe3+ decrease iron acquisition rates by Strategy I organisms via three separate mechanisms.

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