Thermal adaptation and acclimation of ecotypic populations of Spirodela polyrhiza (Lemnaceae): thermostability and apparent activation energy of NAD malate dehydrogenase

1981 ◽  
Vol 59 (6) ◽  
pp. 1061-1068 ◽  
Author(s):  
Dominique Davidson ◽  
Jean-Pierre Simon
Keyword(s):  
Activation Energy ◽  
Malate Dehydrogenase ◽  
Aquatic Plant ◽  
Thermal Adaptation ◽  
Terrestrial Plants ◽  
Spirodela Polyrhiza ◽  
Average Temperature ◽  
Origin Activation ◽  
Regulatory Systems ◽  
Bodies Of Water

Eleven ecotypes of Spirodela polyrhiza (L.) Schleid., an aquatic plant possessing an extensive geographic distribution, were studied to detect adaptive and acclimatory metabolic changes through a study of the thermostability and activation energy of malate dehydrogenase. Colonies were grown under controlled conditions with temperature (18, 23, and 28 °C) as the only variable. Thermostability is found to be affected by experimental temperatures (acclimation) but not by origin temperatures; there is genetic differentiation but related to some other environmental conditions than average temperature at the site of origin. Activation energy is unaffected by experimental temperatures or origin. It is suggested that, as S. polyrhiza naturally grows in bodies of water, it is less exposed to temperature variations than terrestrial plants, but is more affected by other physicochemical environmental factors; its main metabolic regulatory systems do not appear to be associated with thermal controls.

scholarly journals Identification, Phylogeny, and Comparative Expression of the Lipoxygenase Gene Family of the Aquatic Duckweed, Spirodela polyrhiza, during Growth and in Response to Methyl Jasmonate and Salt

2020 ◽  
Vol 21 (24) ◽  
pp. 9527
Author(s):  
Rakesh K. Upadhyay ◽  
Marvin Edelman ◽  
Autar K. Mattoo
Keyword(s):  
Fatty Acids ◽  
Gene Family ◽  
Methyl Jasmonate ◽  
Aquatic Plant ◽  
Plant Hormone ◽  
Feedback Regulation ◽  
Spirodela Polyrhiza ◽  
Opposite Trend ◽  
Lipoxygenase Gene ◽  
Lipoxygenase Gene Family

Lipoxygenases (LOXs) (EC 1.13.11.12) catalyze the oxygenation of fatty acids and produce oxylipins, including the plant hormone jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA). Little information is available about the LOX gene family in aquatic plants. We identified a novel LOX gene family comprising nine LOX genes in the aquatic plant Spirodela polyrhiza (greater duckweed). The reduced anatomy of S. polyrhiza did not lead to a reduction in LOX family genes. The 13-LOX subfamily, with seven genes, predominates, while the 9-LOX subfamily is reduced to two genes, an opposite trend from known LOX families of other plant species. As the 13-LOX subfamily is associated with the synthesis of JA/MeJA, its predominance in the Spirodela genome raises the possibility of a higher requirement for the hormone in the aquatic plant. JA-/MeJA-based feedback regulation during culture aging as well as the induction of LOX gene family members within 6 h of salt exposure are demonstrated.

Freezing Characteristics of Isolated Pig and Human Hepatocytes

1997 ◽  
Vol 6 (2) ◽  
pp. 173-183 ◽  
Author(s):  
T.B. Darr ◽  
A. Hubel
Keyword(s):  
Activation Energy ◽  
Thermodynamic Model ◽  
Cellular Response ◽  
Isolated Hepatocytes ◽  
Human Hepatocytes ◽  
Ice Formation ◽  
Hep G2 ◽  
Average Temperature ◽  
Intracellular Ice Formation ◽  
Intracellular Ice

The cellular response of isolated hepatocytes from pigs, humans, and human hepatoblastoma cells to freezing was characterized using cryomicroscopy and analyzed using a thermodynamic model for water transport and Intracellular Ice Formation (IIF). The value for the reference permeability, Lpg, was found to be 5.8(10)-13, 1.62(10)13, and 2.7(10)-14 m/Ns for pig, human, and Hep G2/C3A cells, respectively. The activation energy, Elp, was found to be 480 kJ/mol for pig hepatocytes, 216 kJ/mol for human, and 121 kJ/mol for Hep G2/C3A cells. The average temperature at which IIF (TavgIIF) occurs was calculated to be -7.24 + 2.3°C for pig hepatocytes, -8.5 + 2.6°C for human hepatocytes, and -9.6 + 4.5°C for Hep G2/C3A cells. These results indicate that the freezing characteristics of pig and human cells are distinct and that the specific freezing characteristics need to be understood for the development of appropriate freezing protocols.

scholarly journals Pathway of synthesis of 3,4- and 4,5-phosphorylated phosphatidylinositols in the duckweed Spirodela polyrhiza L

1993 ◽  
Vol 290 (1) ◽  
pp. 145-150 ◽  
Author(s):  
C A Brearley ◽  
D E Hanke
Keyword(s):  
Aquatic Plant ◽  
Kinase Activity ◽  
Specific Radioactivity ◽  
Animal Cells ◽  
Spirodela Polyrhiza ◽  
Atp Pool ◽  
The Individual ◽  
In Vivo Synthesis

[3H]Inositol and [32P]Pi labelling of the aquatic plant Spirodela polyrhiza L. revealed the presence of PtdIns(3,4)P2, in addition to PtdIns3P, PtdIns4P and PtdIns(4,5)P2 previously identified [Brearley and Hanke (1992) Biochem. J. 283, 255-260]. PtdIns(3,4,5)P3 was not detected. Throughout a 40 min [32P]Pi-labelling period the specific radioactivity of the gamma-phosphate of ATP and of the ATP pool as a whole increased. Chemical and enzymic dissection of phosphoinositides obtained from plants labelled for 35 min with [32P]Pi showed that over 99.7% of the label in PtdIns3P and PtdIns4P was accounted for by the monoester phosphates. The 3- and 4-monoester phosphates of PtdIns(3,4)P2 accounted for 23.1% and 76.6% respectively of the label, whereas the 4- and 5-monoester phosphates of PtdIns(4,5)P2 accounted for 21.1% and 78.6% respectively. These results are consistent with the synthesis of PtdIns(4,5)P2 via PtdIns4P. The labelling of the individual phosphates of PtdIns(3,4)P2 is, however, inconsistent with synthesis from PtdIns(4,5)P2 via PtdIns(3,4,5)P3, but instead suggests that PtdIns(3,4)P2 is synthesized by 4-phosphorylation of PtdIns3P. These results afford the first evidence that in plants in vivo, synthesis of PtdIns(4,5)P2 follows the pathway described in animal cells and also that plants possess PtdIns3P 4-kinase activity similar to that reported from animal cells.

scholarly journals Florida Native Aquatic Plants for Ornamental Water Gardens

EDIS ◽  
1969 ◽  
Vol 2005 (2) ◽  
Author(s):  
Eva C. Worden ◽  
David L. Sutton
Keyword(s):  
Plant Species ◽  
Aquatic Plants ◽  
Aquatic Plant ◽  
Cooperative Extension Service ◽  
Extension Service ◽  
Publication Date ◽  
Original Publication ◽  
Terrestrial Plants ◽  
University Of Florida ◽  
Growing Conditions

Water gardening is increasing in popularity in ornamental landscapes across the country. Ornamental aquatic plants can be grown in small ponds and in containers on the patio or in the yard. Many water-tight containers of many sizes and shapes are available for displaying ornamental aquatic plants. Water gardens provide additional, attractive features to landscapes not available with terrestrial plants. An aquatic plant palette of considerable variety is available for water gardens in Florida (Table 1). The abundance of sunshine and warm temperatures provides ideal growing conditions for many aquatic plant species. This document is ENH988, one of a series of the Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date February 2005. 

Distribution of unusual polyamines in aquatic plants and gramineous seeds

1994 ◽  
Vol 72 (8) ◽  
pp. 1114-1120 ◽  
Author(s):  
Koei Hamana ◽  
Shigeru Matsuzaki ◽  
Masaru Niitsu ◽  
Keijiro Samejima
Keyword(s):  
Key Words ◽  
Aquatic Plants ◽  
Water Hyacinth ◽  
Eichhornia Crassipes ◽  
Aquatic Plant ◽  
Nelumbo Nucifera ◽  
Water Lily ◽  
Spirodela Polyrhiza ◽  
A Minor ◽  
Seedling Leaf

We tested several plants for the occurrence of unusual polyamines such as homospermidine, aminopropylhomospermidine, norspermidine, norspermine, thermospermine, and caldopentamine. The leaf and root of aquatic plants ubiquitously contained homospermidine in addition to usual polyamines such as putrescine, spermidine, spermine, and cadaverine. Homospermidine was widely distributed in the seed, seedling, leaf, and root of gramineous plants such as rice, millet, oat, rye, wheat, barley, corn, sorghum, and timothy as a minor polyamine. Aminopropylhomospermidine was found in the two aquatic plants, the water lily Nymphaca tetragona and the lotus Nelumbo nucifera as a major polyamine, and in the gramineous seeds as a minor polyamine. Norspermidine, norspermine, homospermine, and caldopentamine were detected in two floating aquatic plants, the duckweed Spirodela polyrhiza and the water hyacinth Eichhornia crassipes. Thermospermine was sporadically detected in some aquatic plants and gramineous seeds. Key words: Gramineae, aquatic plant, polyamine, homospermidine, caldopentamine.

scholarly journals 14C Dating of Plant Macrofossils in Lake Sediment

Radiocarbon ◽  
1986 ◽  
Vol 28 (2A) ◽  
pp. 411-416 ◽  
Author(s):  
Michael Andree ◽  
Hans Oeschger ◽  
Ulrich Siegenthaler ◽  
Trudi Riesen ◽  
Markus Moell ◽  
...  
Keyword(s):  
Aquatic Plant ◽  
Hard Water ◽  
Late Glacial ◽  
Plant Macrofossils ◽  
Water Effect ◽  
Terrestrial Plants ◽  
14C Dating ◽  
Pollen Zone ◽  
Swiss Plateau ◽  
Terrestrial Material

Macrofossils of terrestrial plants have been picked from a sediment core taken in Lake Lobsigen, a small lake on the Western Swiss Plateau. The sediments were previously analyzed for pollen composition, plant and animal macrofossils, and stable isotopes. Plant macrofossils were selected near pollen zone boundaries in Late Glacial and early Postglacial sediment for 14C dating by AMS. In the same lake carbonate and gyttja (aquatic plant) samples were dated by decay counting. The dates on terrestrial material are generally younger than those on carbonate and gyttja, ie, material reflecting the 14C/C ratio of dissolved bicarbonate in lake water. This is probably due to a contribution of dissolved limestone carbonate and thus a somewhat reduced 14C/C ratio in the lake's water (hard water effect).

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