Wound hormone

Two proteinase inhibitors, Inhibitors I and II, accumulate in leaves of tomato plants when attacked by chewing Insects or mechanically wounded. The accumulation of these two antinutrient proteins is apparently a defense response and is initiated by the release of a putative wound hormone called the proteinase Inhibitor inducing factor (PIIF). The direction of flow of PIIF out of wounded leaves is primarily towards the apex and transport occurs maximally about 120 min following wounding. After a single severe wound, the vitro translatable tomato leaf mRNA specific for Inhibitors I and II Increases to a maximum within four hours and remains constant for about five hours when it decreases rapidly to about 50% of the maximum. 

When a limb was isolated from the body apart from an artery, vein, and nerve, it was found that transection of the nerve abolished the adrenal response even though the blood supply was intact. These studies do not suggest that a wound hormone is released at the site of injury, although it is possible that histaminelike substances released in damaged tissues stimulate the peripheral nerve endings in the injured part. 

Nakahara, Y, Ogawa, T, Synthesis of (1—>4)-linked galacturonic acid trisaccharides, a proposed plant wound-hormone and a stereoisomer, Carbohydr. Res., 200, 363-375, 1990. 

I, 10-dicarboxylic acid. C,jHm04 mol wt 228.28. C 63.13%, H 8.83%, O 28.03%. A wound hormone of plants. Isoln from pods of green beans English et al. Proc. Nat. Acad. Set. USA 25, 323 (1939). The naturally occurring traumatic acid is the trans-form. Synthesis of the mint-form eidem. 

Oligogalacturonides have been suggested to act as mobile wound hormones, switching on the synthesis of protease inhibitors in several leaves of a tomato plant in response to a localised injury in one leaf [56]. In experiments carried out to test the mobility of pectic fragments within the plant, exogenous C-labelled pectic polysaccharides and H-labelled oligogalacturonides were applied to wound-sites on tomato leaves. The radioactivity moved towards the tip and margins of the leaf (a pattern characteristic of the xylem stream... 

Some of the volatiles formed are known as important aroma components, pheromonones or wound hormones. 

Figure 10 summarizes some results of the lipid-oxidation system in basldlomycetes, leaves, fruits, vegetables, and cereals. It can be seen that there is a development with evolution and differentiation. The enzyme system is highly substrate specific to a (Z,Z)-1,4-pentadiene system converting linoleic- and linolenic acids into carbonyls and oxoacids which may undergo further isomerization (E3) and/or reduction (E4). Some of the components formed are very potent aromatics, pheromones, and wound hormones. Basidio-mycetes and Fungi produce (-)-1-octen-3-ol as their sensorial principle. 9-Oxodecanoic acid is known as queen substance and is the sex pheromone of honey bees. 

Isol. from string bean pods. Plant wound hormone. Spar, sol. H2O. Mp 166-167 . Bpo.ooi 150-160 . 

A wound hormone in plants, traumatin or l-decene-1,10-dicarboxylic acid, was first isolated from bean pods. This substance is capable of inducing renewed cell division and... 

Hydroperoxide lyases catalyse the cleavage of the C-C single bond that is adjacent to the peroxy group. In the case of 13-HpOTrE, the C-12-C-13 bond is cleaved, yielding an unsaturated aldehyde and (9 )-12-oxo-9-dodecenoic acid, which is a precursor of the wound hormone traumatin (Scheme 10). The volatile aldehydes formed via the peroxide lyase pathway exhibit bactericidal properties and are emitted by plants in response to wounding. Thus they may be regarded as part of the plant s disease resistance mechanisms [53]. 

Isol. from enzymic hydrolysates (yeast or mould pectinases) of pectic acid. Also from partial acid hydrol. of Medicago sativa (lucerne) pectin. Possible plant wound hormone. 

Although movement (active or passive) is required, it is uncertain how far the substance must move to qualify as a hormone. Some influences such as wound hormone (Audus 1959) and others (Lang 1966, Steeves and Sussex 1972) span only a few cells. Would it be minimally sufficient for the hormone to move only from one cell to the next Or, like the neurohumors of animal systems, might it be sufficient for the hormone to move only across a membrane ... 

Bonner J, English J Jr (1938) A chemical and physiological study of traumatin, a plant wound hormone. Plant Physiol 13 331-348... 

Winter A (1966) A hypothetical route for the biogenesis of lAA. Planta 71 229-239 Wright STC (1961) A sequential growth response to gibberellic acid, kinetin, and indolyl-acetic acid in the wheat coleoptile. Nature 190 699-700 Zimmerman DC, Coudron CA (1979) Identification of traumatin, a wound hormone, as 12-oxo-trans-lO-dodecanoic acid. Plant Physiol 63 536-541... 

Thus, good substrates for the tea chloroplast enzyme system consisting of lipoxygenase and hydroperoxide lyase were llnolelc acid and linolenlc acid which are commonly occurring fatty acid In plant tissues particularly after acyl hydrolysis of lipids on aging, injury and processing etc. The resultant products are volatiles Including hexanal, (3Z)-hexenal and (2E)-hexenal which are responsible for characteristic odor of plant products. In addition 12-oxo-(9Z)-dodecenolc acid and 12-oxo-(10E)-dodecenolc acid reported as plant wound hormone are formed as a counterpart of volatile C -aldehydes. 

Octadecanoids and wound reparation in plants. The natural product 2( dodecen-l,12-dioic acid, named "traumatic acid", as discovered as the plant wound hormone [1]. As... 

Traumatic Acid, the plant wound hormone, is liberated by damaged tissues, and stimulates growth of parenchymatous celk in the repair process. It has been isolated by English (1939) and shown to be 1 — decene — 1, 10 — dicarboxylic acid, HOOC. CH = CH. (CH ),. CHij. COOH. 

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