Papaya (Carica papaya) is a very important crop in many tropical countries but it is highly susceptible to parasitic diseases, physiological disorders, mechanical damage and fruit overripening. Here we report a study on ACC oxidase cosuppression and its effects on papaya fruit ripening. Papaya ACC ...

In this paper are presented structural analysis and expression studies of one genomic clone encoding a 1-aminocyclopropane-1-carboxylate oxidase (ACC oxidase) from papaya. Using RT-PCR amplification of ACC oxidase cDNAs from ripe papaya, a product of 800 bp was obtained, which after sequence ...

Effects of the synthetic auxin 2,4-dichlorophenoxy-propionic acid (2,4-DP) on 1-aminocyclopropane-1-carboxylate (ACC) synthase and oxidase gene expression by `La France¿ and aroma production by `Bartlett¿ pears (Pyrus communis L.) were investigated. In non-stored, non-treated `LaFrance¿ fruit, the ...

The differential expression of the petunia 1-aminocyclopropane-1-carboxylate (ACC) oxidase gene family during flower development and senescence was investigated. ACC oxidase catalyzes the conversion of ACC to ethylene. The increase in ethylene production by petunia corollas during senescence ...

Differential screening, aimed at the isolation of cDNA clones of mRNAs whose accumulation is influenced by GA3, resulted in the isolation of a cDNA clone of an mRNA whose level was decreased by GA3 in segments of epicotyls of Vigna angularis. The putative protein encoded by this cDNA resembled the 1-aminocyclopropane-1-carboxylate oxidases (ACC ...

Mangoes (Mangifera indica L.) 'Manila' were subjected to the USDA-approved hot water treatment and then exposed to synthetic air mixtures containing 0.5, 0.75 or 1 ml l(-1) of ethylene for 6, 12 or 18 h at 25 degrees C, to induce accelerated ripening. After treatment the mangoes were allowed to ripen in air at 24-25 degrees C. The content of 1-aminocyclopropane-1-carboxylic acid ...

Ethylene formation was studied in 5- to 6-d-old Chenopodium rubrum seedlings under the following light regimes: continuous light (CL), continuous darkness (CD), and alternating light/darkness (12 h of each). No significant regular oscillations in ethylene formation were found in either the CL or CD groups. In the light/dark regime, pronounced diurnal fluctuations in ethylene formation were ...

1-Aminocyclopropane-1-carboxylate (ACC) oxidase catalyzes the oxidation of ACC to ethylene. Following conventional column fractionation, the enzyme was purified 180-fold to near homogeneity with a specific activity of 20 nmol/(mg.min). This purified enzyme preparation migrated as a single protein band with an apparent molecular mass of ...

We investigated the characteristics of ethylene biosynthesis associated with ripening in banana (Musa sp. [AAA group, Cavendish subgroup] cv Grand Nain) fruit. MA-ACS1 encoding 1-aminocyclopropane-1-carboxylic acid (ACC) synthase in banana fruit was the gene related to the ripening process and was inducible by exogenous ethylene. At the onset of the climacteric period in ...

To dissect the role of gibberellins in tomato development, we have constitutively down-regulated the gene GA 20-oxidase1 (GA20ox1). Plants co-suppressed for GA20ox1 (referred to as CO-6 plants) showed vegetative defects typical of GA deficiency such as darker and mis-shaped leaves and dwarfism. CO-6 plants flowered as the controls, although their flowers ...

A theory of fruit climacteric ethylene emission was developed and used as the basis of a simulation model called ETHY. According to the theory, the biosynthetic pathway of ethylene is supplied by ATP and is regulated by 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase. The conjugation of ACC ...

A theory of fruit climacteric ethylene emission was developed and used as the basis of a simulation model called ETHY. According to the theory, the biosynthetic pathway of ethylene is supplied by ATP and is regulated by 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase. The conjugation of ACC ...

-kDa protein from the fungus Trichoderma vride, elicits HR and other defense responses in such plants tabacum by a Trichoderma viride Xylanase is correlated to the accumulation of ACC synthase and ACC oxidase- acterization of the enzyme produced by Trichoderma viride. Plant Physiol. 95, 316�323. Enkerli, J., Felix, G

Submergence strongly stimulates petiole elongation in Rumex palustris, and ethylene accumulation initiates and maintains this response in submerged tissues. cDNAs from R. palustris corresponding to a 1-aminocyclopropane-1-carboxylate (ACC) oxidase gene (RP-ACO1) were isolated from elongating petioles and used to study the expression of the corresponding ...

A highly sensitive laser-driven photoacoustic detector responsive to [less than or equal to]2.1 nmol m-3 ethylene (50 parts per trillion [v/v]) was used for ethylene analysis. Dark-grown plants of Potamogeton pectinatus L. growing from small tubers made no ethylene. Exposure of shoots to white light, wounding, submergence in water followed by desubmergence, partial oxygen shortage, indole acetic ...

A highly sensitive laser-driven photoacoustic detector responsive to [less than or equal to]2.1 nmol m-3 ethylene (50 parts per trillion [v/v]) was used for ethylene analysis. Dark-grown plants of Potamogeton pectinatus L. growing from small tubers made no ethylene. Exposure of shoots to white light, wounding, submergence in water followed by desubmergence, partial oxygen shortage, indole acetic ...

The role of free radicals in the conversion of 1-aminocyclopropane-1-carboxylic acid (ACC) to ethylene by a membrane-bound enzyme from carnation petals was studied. The membrane preparation oxidized ACC more effectively than it oxidized cyclopropaneamine or 2-keto-4-methylthiobutyric acid (KMB). All these substrates were oxidized chemically by NaOCl to ...

The properties of ethylene-forming enzyme (EFE) (or 1-amino-cyclopropane-1-carboxylic acid oxidase; ACC-oxidase), the terminal enzyme in the synthesis of one of the main plant phytohormones, are reviewed. The properties of the isolated enzyme differ from those in the cell. There are apparently two forms of EFE in cells, one localized in vacuoles and the ...

PURPOSE OF WORK: Melons have short shelf-lives due to fruit ripening caused by ethylene production. The 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene is essential for ethylene biosynthesis. As fruit ripening in other fruit crops can be deterred by down-regulation of ACC oxidase expression, we have ...

Mutant sorghum (Sorghum bicolor [L.] Moench) deficient in functional phytochrome B exhibits reduced photoperiodic sensitivity and constitutively expresses a shade-avoidance phenotype. Under relatively bright, high red:far-red light, ethylene production by seedlings of wild-type and phytochrome B-mutant cultivars progresses through cycles in a circadian rhythm; however, the phytochrome B ...

1-Aminocyclopropane-1-carboxylate (ACC) oxidase catalyzes the final reaction of the ethylene biosynthetic pathway, converting the unusual cyclic amino acid, ACC, into ethylene. Past studies have shown a possible link between ethylene and compression wood formation in conifers, but the relationship has received no more than modest study ...

1-Aminocyclopropane-1-carboxylate (ACC) oxidase catalyses the final step in the biosynthesis of the plant hormone ethylene. The successful overexpression and characterization of active ACC oxidase from tomato has been achieved. PCR was used to insert the corrected cDNA coding for the tomato ACC ...

The connection between classical phytohormone-ethylene and two signaling molecules, nitric oxide (NO) and hydrogen cyanide (HCN), was investigated in dormancy removal and germination "sensu stricto" of apple (Malus domestica Borkh.) embryos. Deep dormancy of apple embryos was removed by short-term (3-6�h) pre-treatment with NO or HCN. NO- or HCN-mediated stimulation of germination was associated ...

Ethylene formation was studied in 5- to 6-d-old Chenopodium rubrum seedlings under the following light regimes: continuous light (CL), continuous darkness (CD), and alternating light/darkness (12 h of each). No significant regular oscillations in ethylene formation were found in either the CL or CD groups. In the light/dark regime, pronounced diurnal fluctuations in ethylene formation were ...

By using two-dimensional eletrophoresis method, this paper studied the protein expression level in Baphicacanthus cusia (Nees) Bremek leaves after sprayed with exogenous salicylic acid (SA). A total of significantly different 20 protein spots were obtained, among which, eight protein spots were indentified, being of ATP synthase, alpha tubulin, cell division protein, glyceraldehydephosphate ...

Temporal and spatial expression patterns of genes encoding 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS1 and ACS2) and ACC oxidase (ACO), ACC concentration, and ethylene production in leaves and fruit of 'Valencia' orange (Citrus sinensis [L.] Osbeck) were examined in relation to differential abscission ...

Changes in ethylene production rate, respiration rate, and aroma volatile composition was determined from the immature to mature stage in "Hujingmilu" peach (Prunus presica) fruit. Flesh firmness, fruit size, ground color of skin, and total soluble solids (TSS), titratable acidity (TA) in juice were analyzed, and ACC, ACC synthase and ...

By comparing the effects of strong and weak promoters that drive sense chalcone synthase (Chs) transgenes in large populations of independently transformed plants, we show here that a strong transgene promoter is required for high-frequency cosuppression of Chs genes and for production of the full range of cosuppression phenotypes. In addition, sense Chs ...

Ethylene regulates plant growth in response to many adverse environmental conditions, including the induction of aerenchyma, i.e. the formation of air spaces, in flooded roots in an effort to maintain oxygen levels. In this work, quantitative RT-PCR and in situ RNA hybridization were used to determine how the expression of the ethylene biosynthetic machinery in maize roots is spatially and ...

Ethylene is required for climacteric fruit ripening. Inhibition of ethylene biosynthesis genes, 1-aminocyclopropane-1-carboxylate (ACC) synthase and ACC oxidase, prevents or delays ripening, but it is not known how these genes are modulated during normal development. LeHB-1, a previously uncharacterized tomato homeobox protein, was ...

Ethylene production from florets of Shogun harvested broccoli (Brassica oleracea L. var. italica) held at 20C in darkness increased as the sepal tissues yellowed. The pattern of respiration rate and ethylene production from branchlets or entire heads was similar, although the magnitude of ethylene and carbon dioxide production appeared to be diluted by the other fleshy stem tissues. The ...

Using leaf epidermis from Vicia faba, we tested whether auxin-induced stomatal opening was initiated by auxin-induced ethylene synthesis. Epidermis was dark-incubated in buffered KNO3 containing 0.1 mM alpha-napthalene acetic acid or 1 mM indole-3-acetic acid. Maximum net opening was ca. 4 micron after 6 h. Opening was reversed by 20 microM ABA, 0.1 mM CaCl2. 1-Aminocyclopropane carboxylic acid ...

This article describes a successful application of l-lysine epsilon-oxidase (EC 1.4.3.20) for l-lysine determination. l-Lysine epsilon-oxidase was isolated from culture supernatant of Marinomonas mediterranea NBRC 103028(T) and was used for l-lysine determination. Comparison of the characteristics of l-lysine epsilon-oxidase with ...

The role of ethylene in regulating sugar, acid, texture and volatile components of fruit quality was investigated in transgenic apple fruit modified in their capacity to synthesize endogenous ethylene. Fruit obtained from plants silenced for either ACS (ACC synthase; ACC-1-aminocyclopropane-1-carboxylic acid) or ACO (ACC ...

BACKGROUND: 'Hami' melon is susceptible to softening during postharvest storage at ambient temperature, which enhances postharvest deterioration and limits transportation and storage. To look for a method of softening control, the effect of 1-methylcyclopropene (1-MCP) on regulating postharvest softening of 'Hami' melon fruit was investigated. RESULTS: 1-MCP treatment at 1 �L L(-1) significantly ...

In order to understand more details about the role of abscisic acid (ABA) in fruit ripening and senescence of tomato, two cDNAs (LeNCED1 and LeNCED2) which encode 9-cis-epoxycarotenoid dioxygenase (NCED) as a key enzyme in ABA biosynthesis, two cDNAs (LeACS2 and LeACS4) which encode 1-aminocyclopropane-1-carboxylic acid (ACC) synthase, and one cDNA (LeACO1) which encodes ...

We show that above a certain threshold concentration, ozone leads to leaf injury in tomato (Lycopersicon esculentum). Ozone-induced leaf damage was preceded by a rapid increase in 1-aminocyclopropane-1-carboxylic acid (ACC) synthase activity, ACC content, and ethylene emission. Changes in mRNA levels of specific ACC synthase, ...

Ethylene plays a key role in the elongation of exploratory and root hair systems in plants, as demonstrated by pharmacological modulation of the activity of ethylene biosynthesis enzymes: ACC synthase (ACS) and ACC oxidase (ACO). Thus, treatments with high concentrations (10 �M) of aminoethoxyvinylglycine (AVG, inhibitor of ACS) and ...

The role of ethylene (ET) in resistance to infection with blast fungus (Magnaporthe grisea) in rice (Oryza sativa) is poorly understood. To study it, we quantified ET levels after inoculation, using young rice plants at the four-leaf stage of rice cv Nipponbare (wild type) and its isogenic plant (IL7), which contains the Pi-i resistance gene to blast fungus race 003. Small necrotic lesions by ...

Conifer stem pest resistance includes constitutive defenses that discourage invasion and inducible defenses, including phenolic and terpenoid resin synthesis. Recently, methyl jasmonate (MJ) was shown to induce conifer resin and phenolic defenses; however, it is not known if MJ is the direct effector or if there is a downstream signal. Exogenous applications of MJ, methyl salicylate, and ethylene ...

co-suppression approach, exhibited defects in multiple aspects of plant development, including plants (with the exception of early seedling defects, see below). Although the phenotype of a given phyllotaxy (Medford et al., 1992). In the CSN3 co-suppression plants, a variety of leaf shape defects have

The micropylar endosperm cap covering the radicle in the mature seeds of most angiosperms acts as a constraint that regulates seed germination. Here, we report on a comparative seed biology study with the close Brassicaceae relatives Lepidium sativum and Arabidopsis thaliana showing that ethylene biosynthesis and signaling regulate seed germination by a mechanism that requires the coordinated ...

The micropylar endosperm cap covering the radicle in the mature seeds of most angiosperms acts as a constraint that regulates seed germination. Here, we report on a comparative seed biology study with the close Brassicaceae relatives Lepidium sativum and Arabidopsis thaliana showing that ethylene biosynthesis and signaling regulate seed germination by a mechanism that requires the coordinated ...