Short chain oligogalacturonides induce ethylene production and expression of the gene encoding aminocyclopropane 1-carboxylic acid oxidase in tomato plants

Ethylene is important in industry and biological signaling. In plants, ethylene is produced by oxidation of 1-aminocyclopropane-1-carboxylic acid, as catalyzed by 1-aminocyclopropane-1-carboxylic acid oxidase. Bacteria catalyze ethylene production, but via the four-electron oxidation of 2-oxoglutarate to give ethylene in an arginine-dependent reaction. Crystallographic and biochemical studies on the Pseudomonas syringae ethylene-forming enzyme reveal a branched mechanism. In one branch, an apparently typical 2-oxoglutarate oxygenase reaction to give succinate, carbon dioxide, and sometimes pyrroline-5-carboxylate occurs. Alternatively, Grob-type oxidative fragmentation of a 2-oxoglutarate–derived intermediate occurs to give ethylene and carbon dioxide. Crystallographic and quantum chemical studies reveal that fragmentation to give ethylene is promoted by binding of l-arginine in a nonoxidized conformation and of 2-oxoglutarate in an unprecedented high-energy conformation that favors ethylene, relative to succinate formation.

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A tomato antisense 1-aminocyclopropane-1-carboxylic acid oxidase gene causes reduced ethylene production in transgenic broccoli

Functional Plant Biology ◽

10.1071/pp98083 ◽

1999 ◽

Vol 26 (2) ◽

pp. 179 ◽

Cited By ~ 18

Author(s):

Maria X. Henzi ◽

David L. McNeil ◽

Mary C. Christey ◽

Ross E. Lill

Keyword(s):

Carboxylic Acid ◽

Ethylene Production ◽

Oxidase Activity ◽

Production Systems ◽

Acc Oxidase ◽

Initial Increase ◽

Acid Oxidase ◽

Oxidase Gene ◽

Transgenic Lines ◽

Transgenic Broccoli

In this paper 11 transgenic broccoli (Brassica oleracea L. var. italica) lines containing a tomato antisense 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene from pTOM13 were evaluated. Changes in respiration, ethylene production and ACC oxidase activity were studied in mature flowers. Averaged across all ACC oxidase transgenic lines, there was an initial increase followed by a substantial decrease in ethylene production compared with the controls. Of the 11 transgenic lines, 10 lines showed a significant reduction in fethylene production relative to the controls from 50 h after harvest. Green Beauty flowers showed a significant reduction in respiration between the transgenics and control and demonstrated how ethylene levels could control the stable, or climacteric-like increase in respiration. ACC oxidase activity was higher in transgenic plants, consistent with the initially higher ethylene production. ACC oxidase activity did not, however, reflect the increase in ethylene production found after 50 h for the controls. These results suggest that two ethylene production systems may operate with only the second being inhibited by the antisense ACC oxidase used and that the later system was not detected by the ACC oxidase assay used. The results do show that post-harvest ethylene synthesis and therefore possibly broccoli senescence can be regulated by using an antisense ACC oxidase gene.

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Transport of 1-aminocyclopropane-1-carboxylic acid (ACC) in the transpiration stream of tomato (Lycopersicon esculentum) in relation to foliar ethylene production and petiole epinasty

Functional Plant Biology ◽

10.1071/pp97105 ◽

1998 ◽

Vol 25 (4) ◽

pp. 453 ◽

Cited By ~ 43

Author(s):

Mark A. Else ◽

Michael B. Jackson

Keyword(s):

Carboxylic Acid ◽

Lycopersicon Esculentum ◽

Ethylene Production ◽

Xylem Sap ◽

Tomato Plants ◽

Transpiration Stream ◽

Whole Plant ◽

Xylem Sap Flow ◽

Nitrogen Phosphorus Detector ◽

Nitrogen Phosphorus

We investigated the concentration and delivery of 1-aminocyclopropane-1-carboxylic acid (ACC) in the transpiration stream of flooded and well-drained 1-month-old tomato plants (Lycopersicon esculentum Mill. cv. Ailsa Craig) over time in parallel with foliar ethylene production and petiole epinasty. ACC was measured by gas chromatography using a nitrogen–phosphorus detector. Before analysis, roots of freshly detopped plants were pressurised pneumatically to make xylem sap flow at rates similar to those of whole plant transpiration. Delivery of ACC from roots to shoots of well-drained plants was sufficient to support basal ethylene production in shoots of unstressed plants. Delivery from flooded, oxygen-deficient, roots increased after 6 h and coincided with the onset of epinastic leaf curvature. Further increases in ACC delivery and epinastic curvature occurred later in the photoperiod. After 24 h flooding, ACC delivery in xylem sap was 28 times more than in well-drained plants. This increased export of ACC from flooded roots was more than sufficient to account for the extra ethylene production in the shoots and coincided with ACC accumulation in the leaves. Removing the shoot before flooding did not reduce ACC export from oxygen-deficient roots indicating that the ACC originated in roots and not the shoot. Increased ethylene production in petioles of flooded plants lagged 18 h behind epinasty.

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Lipoxygenase and Its Relationship with Ethylene During Ripening of Genetically Modified Tomato (Solanum lycopersicum)

Food Technology and Biotechnology ◽

10.17113/ftb.58.02.20.6207 ◽

2020 ◽

Vol 58 (2) ◽

pp. 223-229

Author(s):

Arturo Alberto Velázquez-López ◽

Javier De La Cruz-Medina ◽

Elizabeth León-García ◽

Cristóbal Torres-Palacios ◽

Gilber Vela-Gutiérrez ◽

...

Keyword(s):

Gene Expression ◽

Carboxylic Acid ◽

Ethylene Production ◽

Oxidase Activity ◽

Genetically Modified ◽

Lipoxygenase Activity ◽

Acid Oxidase ◽

Wild Type ◽

Tomato Fruits ◽

Exogenous Ethylene

Research background. TomloxB is the main isoform of lipoxygenase associated with ripening and senescence of fruits. On the other hand, ethylene, a gaseous hormone, is essential for the regulation of ripening in climacteric fruits like tomatoes. However, the relationship between TomloxB and ethylene production has not been thoroughly studied. Therefore, we aim to assess the effect of exogenous ethylene in transgenic tomatoes that contain a silenced TomloxB gene, and subsequently evaluate lipoxygenase activity, 1-aminocyclopropane-1-carboxylic acid oxidase and ethylene production; as well as to quantify the expression of the genes encoding 1-aminocyclopropane-1-carboxylic acid oxidase and TomloxB.Experimental approach. To investigate the effect of lipoxygenase and 1-aminocyclopropane-1-carboxylic acid oxidase activity, fruits harvested at the stages of break, turning and pink were used. Tomatoes at break stage collected from transgenic and wild type plants were used to determine ethylene production and gene expression. Genetically modified and wild type tomato fruits were exposed to 100 μL/L exogenous ethylene. Lipoxygenase activity was measured spectrophotometrically. Activity of 1-aminocyclopropane-1-carboxylic acid oxidase and ethylene production were determined by gas chromatography. Oligonucleotides for differentially expressed genes: 1-aminocyclopropane-1-carboxylic acid oxidase and TomloxB were used to determine gene expression by real-time PCR.Results and conclusions. The data showed that silencing of TomloxB caused a reduction in lipoxygenase activity and ethylene production in tomato fruits, and also reduced 1-aminocyclopropane-1-carboxylic acid oxidase activity. Hence, the addition of exogenous ethylene increased lipoxygenase activity in all treatments and 1-aminocyclopropane-1-carboxylic acid oxidase activity only in transgenic lines at break stage, consequently there was a positive regulation between TomloxB and ethylene, as increasing the amount of ethylene increased the activity of lipoxygenase. The results suggest that lipoxygenase may be a regulator of 1-aminocyclopropane-1-carboxylic acid oxidase and production of ethylene at break stage.Novelty and scientific contribution. These results lead to a better understanding of the metabolic contribution of TomloxB in fruit ripening and how it is linked to the senescence-related process, which can lead to a longer shelf life of fruits. Understanding this relationship between lipoxygenase and ethylene can be useful for better post-harvest handling of tomatoes.

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