Gibberellins in higher plants

As in past years several studies of the metabolism of exogenous gibberellins in higher plants have appeared some of this work is of little value as the R. C. Coolbaugh and R. Hamilton, Plant Physiol., 1976, 57, 245. 

Gibberellins in Higher Plants The Biosynthetic Pathway Leading to GAi... 

Spray, C. R. and B. O. Phinney, Gibberellins in higher plants The biosynthetic pathway leading to GAi in Ecology and Metabolism of Lipids (G. Fuller and W. D. Nes, eds.), ACS Symposium Series 325,25-43, American Chemical Society, Washington, DC, 1987. 

In addition to the isolation of these four pure gibberellins, a vast body of evidence indicates the widespread occurrence in higher plants of extractable substances with gibberellin-like biological properties. It is instructive to compare published Rf values for unidentified gibberellin-like substances of crude extracts with the Rf values of the known gibberellins. 

Gibberellin Biosynthesis in the Fungus Gibberella fujikuroi and in Higher Plants... 

MacMillan, J., Suter, P.J. "The occurrence of gibberellin A] in higher plants isolation from the seed of runner bean (Phaseolus multiflorus)." Naturwissen. 1958, 1 5, 1 6. 

Within a few years the wide spectrum of natural gibberellins that exist in higher plants, and the range of biological activities was beginning to be known. 

Of the 72 gibberellins identified by gas chromatography-mass spectrometry (GC-MS), eleven are found only in the ftmgus, G. fuiikuroi. forty seven in higher plants while fourteen additional GAs are common to both groups. The gibberellins are tetracyclic diterpene acids, having in common the carbon skeleton,... 

In the case of the gibberellins it has been demonstrated that their pathway is identical, or quite similar, in higher plants and in the fungus Gibberella fujikuroi irrespective of whether they function as hormones or as typical secondary products as in the case of the fungus (Eef. 20, 22). 

Thus, phenolic compounds and morphactin - which inhibit cell elongation and cell division in higher plants -have no effect on biosynthesis of auxins and gibberellins in cultures of certain fungi. Their action seems to specific for higher plants. 

Recently, the isolation of gibberellin and kinin provided further proof for the coumarin-auxin relation. These substances are included among the plant hormones, although gibberellic acid, a representative of gibberellins, was first isolated as a fungal metabolite, and kinetin, the best known kinin derivative was produced from nucleic acids [119-121]. Both of these compounds, however, were also found in higher plants. 

GibbereUins are active as hormones in higher plants (E 3.1). In the fungus Fusarium moniliforme (Gibberella fujikuroi) they are built as phytotoxins (E 5.4). The antheridiogens, which possess hormone activity in ferns are structurally related to the gibberellins (E 3.1). 

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