Mild temperature stress modulates cytokinin content and cytokinin oxidase/dehydrogenase activity in young pea plants

Cytokinin oxidase/dehydrogenase (CKX: EC 1.5.99.12) is able to provide a means for the rapid turnover of its substrate and it has been considered responsible for changes in the cytokinin pool in an adverse environment. Mild temperature stresses (10°C and 33°C average) were applied to young pea plants of two varieties (cvs. Manuela and Scinado) in order to assess the response of the cytokinin pool and CKX activity to altered growth conditions. Both temperature treatments increased the isopentenyl adenine (iP) and isopentenyl adenine riboside (iPR) contents in stressed plants. This trend was far more pronounced in the leaves. Low temperature additionally resulted in elevated cis zeatin riboside ( cis ZR) and CKX activity. Heat did not influence the enzymatic activity in the leaves, while opposing trends were observed in the root-derived CKX activity of the two tested varieties. The data suggest that variance in the temperature provokes adaptive reactions in the cytokinin pool, which is maintained by CKX activity.

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THE EFFECT OF BACTERIAL STRAINS ON THE ENZYMATIC ACTIVITY OF SOILS IN IMPACT ZONE OF ATAMAN LAKE

STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS. In the frame of the XXIII Agribusiness Forum of the South of Russia and the Exhibition «Interagromash» Volume 1 ◽

10.23947/interagro.2020.1.119-120 ◽

2020 ◽

Author(s):

V.V. Zinchenko ◽

◽

E.S Fedorenko ◽

A.V Gorovtsov ◽

T.M Minkina ◽

...

Keyword(s):

Enzymatic Activity ◽

Dehydrogenase Activity ◽

Contaminated Soil ◽

Model Experiment ◽

Impact Zone ◽

Bacterial Strains ◽

The Impact

As a result of the model experiment, an increase in the enzymatic activity of meadow chernozem of the impact zone of Ataman Lake with the introduction of a strains mixture of metal-resistant microorganisms into the soil was established. The experiment has shown that the application of bacterial strains increases the dehydrogenase activity of contaminated soil by 51.8% compared to the variant without remediation

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Low-Temperature Diffusivity of Hydrogen in Different Silicon Substrates

MRS Proceedings ◽

10.1557/proc-378-359 ◽

1995 ◽

Vol 378 ◽

Cited By ~ 1

Author(s):

Xiaojun Deng ◽

Bhushan L. Sopori

Keyword(s):

Low Temperature ◽

Carbon Content ◽

Oxygen Concentration ◽

Hydrogen Diffusion ◽

Growth Conditions ◽

Growth Speed ◽

Silicon Substrates ◽

Vacancy Mechanism ◽

Speed Increase

AbstractThe diffusivity of deuterium (D) at 250°C was determined in silicon samples grown by different techniques. It is found that the diffusivity increases with the growth speed, increase in carbon content and a decrease in oxygen concentration of the substrate. These growth conditions correlate well with the concentration of vacancy-type defects in the as-grown state. Hence, we conclude that a vacancy mechanism is responsible for low-temperature hydrogen diffusion in silicon. The highest diffusivity for hydrogen, calculated from these data, was found to be 3 × 10−7 cm2/s.

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GENETIC EVIDENCE FOR INTERACTION BETWEEN NONHOMOLOGOUS PROTEINS IN YEAST AND A CASE OF SUPPRESSION AT THE HIS1 LOCUS

Genetics ◽

10.1093/genetics/94.2.327 ◽

1980 ◽

Vol 94 (2) ◽

pp. 327-339 ◽

Cited By ~ 1

Author(s):

Richard Snow

Keyword(s):

Enzyme Activity ◽

Low Temperature ◽

Enzymatic Activity ◽

Temperature Effect ◽

Conformational Change ◽

Minimal Medium ◽

Genetic Evidence ◽

Structural Genes ◽

Wild Type ◽

Is Strain

ABSTRACT The HIS1 and THR4 loci are the structural genes for phosphoribosyl-ATP pyrophosphorylase and threonine synthetase, respectively. The allele his1-IS has no enzyme activity at 30", but does have activity at 15" provided the cell contains the wild-type THR4 allele or a suppressing allele at another locus, designated SUP(his1-1S). Under these conditions, cells with the hisl-IS mutation are capable of growth on minimal medium at 15". Three kinds of reversions of a hisl-IS thr4 sup(his1-IS) strain to histidine prototrophy have been obtained: (1) his1-IS locus reversions to HIS1 that restore growth without added histidine at 30", (2) thr4 reversions to THR4 that simultaneously eliminate the requirement for threonine and restore the low-temperature effect on the his1-IS allele, and (3)mutations from sup to SUP. The SUP allele is not an ochre suppressor, and it is not linked to either HISI, THR4 or a centromere. It may represent a missense suppressor. I t is proposed that the effect ofTHR4 is caused by aggregation of the wild-type threonine synthetase with defective his1-IS monomers, causing a favorable conformational change in the histidine protein that restores limited enzymatic activity. This can be regarded as a case of complementation between nonhomologous proteins.

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Tuning metal oxide defect chemistry by thermochemical quenching

Physical Chemistry Chemical Physics ◽

10.1039/c9cp06660h ◽

2020 ◽

Vol 22 (11) ◽

pp. 6308-6317

Author(s):

Shehab Shousha ◽

Sarah Khalil ◽

Mostafa Youssef

Keyword(s):

Low Temperature ◽

Metal Oxide ◽

Metal Oxides ◽

First Principles ◽

Growth Conditions ◽

Defect Chemistry ◽

First Principles Calculations

Based on first-principles calculations, we show how to tune the low temperature defect chemistry of metal oxides by varying growth conditions.

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Low-temperature growth conditions of YBa2Cu3O7−δ using Ba–Cu–Ag–O–F solvent

Journal of Crystal Growth ◽

10.1016/s0022-0248(01)02096-6 ◽

2002 ◽

Vol 236 (1-3) ◽

pp. 221-224 ◽

Cited By ~ 9

Author(s):

Yasuji Yamada ◽

Toshihiro Suga ◽

Izumi Hirabayashi

Keyword(s):

Low Temperature ◽

Growth Conditions ◽

Temperature Growth ◽

Low Temperature Growth

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Intrafibre distribution of succinate dehydrogenase in cat tibialis anterior motor units

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y92-133 ◽

1992 ◽

Vol 70 (7) ◽

pp. 970-976 ◽

Cited By ~ 7

Author(s):

Thomas P. Martin ◽

V. R. Edgerton

Keyword(s):

Mechanical Properties ◽

Enzymatic Activity ◽

Succinate Dehydrogenase ◽

Dehydrogenase Activity ◽

Tibialis Anterior ◽

Radial Distance ◽

Motor Units ◽

Computer Assisted ◽

Mitochondrial Enzymes ◽

Succinate Dehydrogenase Activity

Using isolated ventral root filament stimulation and glycogen depletion techniques, 14 motor units from the cat tibialis anterior were studied. Based on their mechanical properties, the units were classified as either slow-fatigue resistant, fast-fatigue resistant, fast-fatigue intermediate, or fast-fatigable. Quantitative histochemical and computer assisted image analysis techniques were used to determine the activity of succinate dehydrogenase in a population of fibres in each unit. In addition, the intrafibre distribution of succinate dehydrogenase activity was measured in those same fibres by calculating the enzymatic activity of circumferential layers every 0.5 μm starting from the fibre edge to its centre. It was established that enzymatic activity and radial distance were linearly related in the fibres. A range in succinate dehydrogenase activity (mean coefficient of variation, 29%) was observed among the fibres of a unit. In contrast, the intrafibre distribution of that activity was rather consistent (mean variation, 4%) across the fibres of a unit. Further, the intrafibre distribution was similar among the fibres of units classified as the same type. However, the intrafibre distribution was disparate among the different unit types. These data suggest that the intrafibre distribution of mitochondrial enzymes may contribute to the mechanical properties of a motor unit. In this regard, a hypothesis is proposed that describes how the absolute activity of a mitochondrial enzyme, and the intrafibre distribution of that activity, may interactively contribute to the fatigue resistance of a unit.Key words: mitochondria, quantitative histochemistry, fatigue.

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Group 5 LEA protein, ZmLEA5C , enhance tolerance to osmotic and low temperature stresses in transgenic tobacco and yeast

Plant Physiology and Biochemistry ◽

10.1016/j.plaphy.2014.08.016 ◽

2014 ◽

Vol 84 ◽

pp. 22-31 ◽

Cited By ~ 26

Author(s):

Yang Liu ◽

Li Wang ◽

Shanshan Jiang ◽

Jiaowen Pan ◽

Guohua Cai ◽

...

Keyword(s):

Low Temperature ◽

Transgenic Tobacco ◽

Lea Protein ◽

Temperature Stresses ◽

Group 5

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Effects of jointing and booting low temperature stresses on grain yield and yield components in wheat

Agricultural and Forest Meteorology ◽

10.1016/j.agrformet.2017.04.016 ◽

2017 ◽

Vol 243 ◽

pp. 33-42 ◽

Cited By ~ 21

Author(s):

Hongting Ji ◽

Liujun Xiao ◽

Yumin Xia ◽

Hang Song ◽

Bing Liu ◽

...

Keyword(s):

Low Temperature ◽

Grain Yield ◽

Yield Components ◽

Temperature Stresses ◽

Yield And Yield Components

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TEM observation for low-temperature grown spinel-type LiMn2O4crystals

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s205327331409250x ◽

2014 ◽

Vol 70 (a1) ◽

pp. C749-C749

Author(s):

Kunio Yubuta ◽

Yusuke Mizuno ◽

Nobuyuki Zettsu ◽

Shigeki Komine ◽

Kenichiro Kami ◽

...

Keyword(s):

Low Temperature ◽

Manganese Oxides ◽

Low Cost ◽

Active Material ◽

Lithium Ion ◽

Growth Conditions ◽

Rechargeable Batteries ◽

Chemical Compositions ◽

Spinel Type ◽

Average Size

Present spinel-type lithium manganese oxides have attracted much attention as positive-electrode active materials for lithium-ion rechargeable batteries, which are the most sought-after power source for various electric applications, because of their low cost, non-toxicity, and high abundance of source materials compared to the conventionally used LiCoO2 crystals. Spinel-type LiMn2O4 crystals were grown at low-temperature by using a LiCl-KCl flux. The chemical compositions, sizes, and shapes of the LiMn2O4 crystals could be tuned by simply changing the growth conditions. Among the various products, the crystals grown at a low temperature of 873 K showed a small average size of 200 nm. Electron diffraction patterns and TEM images reveal the truncated octahedral shape of the crystals. The flux growth driven by rapid cooling resulted in truncated octahedral LiMn2O4 crystals surrounded by both dominating {111} and minor {100} faces with {311} and {220} edges. Lattice images indicate that crystals grown at a lower temperature have the excellent crystallinity. The small LiMn2O4 crystals grown at 873 K showed better rate properties than the large crystals grown at 1173 K, when used as a positive active material in lithium-ion rechargeable batteries.

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