Metabolism of Indole‐3‐acetaldehyde.

Rajagopal, R.

doi:10.1111/j.1399-3054.1967.tb08385.x

Cited by 29 publications

(17 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It is also metabolized rapidly by tissues and preparations of a number of plants (Lar-.sen 1949. 1951, Valdovinos and Perley 1966, Rajagopal 1967. But all Ihese earlier reports were based on experiments conducted under non-aseptic rotidilions.…”

Section: Introductionmentioning

confidence: 99%

Occurrence and Metabolism of Indoleacetaldehyde in Certain Higher Plant Tissues Under Aseptic Conditions

Rajagopal

1968

Physiologia Plantarum

Self Cite

View full text Add to dashboard Cite

Qualitative and quantitative evidence based on thin‐layer chromatography and the Avena curvature test respectively, are presented for the normal and natural occurrence of indoleacetic acid (IAA), indoleacetaldehyde (IAAld) and tryptophol in the etiolated shoots of Pisum sativum, grown, harvested and extracted under aseptic conditions. Non‐aseptic pea shoots contain much more IAA and IAAld than aseptic ones. Extraneous contribution to the indole pool of pea plants grown under non‐sterile atmosphere, other than by the inherent agency of the plant itself, is therefore not excluded. Indoleacetaldehyde metabolizing activity of the tissues and cell‐free preparations of etiolated Avena seedlings, leading to the production of IAA and tryplophol, is unaffected by the antibiotics actinomycin and streptomycin over a wide range of concentrations. Formation of IAA from IAAld is suppressed by a small degree (10 to 15 %) by chloramphenicol. But this antibiotic does not influence the concurrent production of tryptophol. It is deduced that epiphytic bacteria play little role in the transformation of IAAld to IAA and tryptophol by Avena tissues.

show abstract

Section: Introductionmentioning

confidence: 99%

Occurrence and Metabolism of Indoleacetaldehyde in Certain Higher Plant Tissues Under Aseptic Conditions

Rajagopal

1968

Physiologia Plantarum

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is also formed in vitro by preparations from bacteria, thallophytes, and seed plants from compounds supposed to participate in the biogenesis of IAA (e.g. 18,23). In fact, tryptophol appears to be in an oxidase-reductasemediated equilibrium with the IAA precursor, indole-3-acetaldehyde (5,16).…”

mentioning

confidence: 99%

Metabolism of Tryptophol in Higher and Lower Plants

Laćan¹,

Magnus²,

Šimaga³

et al. 1985

Plant Physiol.

View full text Add to dashboard Cite

Bacteria, thallophytes, and seed plants (107 species), supplied with exogenous indole-3-ethanol (tryptophol), formed one or more of the following metabolites: O-acetyl tryptophoL an unknown tryptophol ester (or a set of structurally closely related esters), tryptophol glucoside, tryptophol plactoside, indole-3-acetic acid (IAA), and indole-3-carboxylic acid. The unknown ester was formed by all species exAmined; 0-acetyl tryptophol appeared sporadically in representatives of most major taxonomic groups. Tryptophol galactoside was found in the algae Chlorella, Euglena, and Ochromoaas. The glucoside was formed by many eucaryotic plants, but not by bacteria; it was a significant tryptophol metabolite in vascular plants. IAA, if detectable at all, was usually a minor metabolite, as should be expected, if tryptophol oxidase responds to feedback inhibition by IAA. Indole-3-carboxylic acid, formed by a few fungi and mosses, was the only tryptophol metabolite detected which is likely to be formed via IAA.Indole-3-ethanol (tryptophol2) has been established as an endogenous plant constituent (6,19,23). It is also formed in vitro by preparations from bacteria, thallophytes, and seed plants from compounds supposed to participate in the biogenesis of IAA (e.g. 18,23). In fact, tryptophol appears to be in an oxidase-reductasemediated equilibrium with the IAA precursor, indole-3-acetaldehyde (5, 16). The oxidase has been isolated and found to be feedback inhibited by IAA (16). This points to the involvement of tryptophol in a mechanism stabilizing auxin levels in plants. Its in vivo significance has, however, remained unclear, because IAA concentrations necessary to inhibit the isolated tryptophol oxidase are larger than bulk concentrations of the hormone in plant tissues (16).Local IAA concentrations at points ofregulation may be higher than bulk concentrations. Also, removal of tryptophol oxidase from its natural subcellular environment may render the enzyme less sensitive to feedback inhibitors. For these reasons, we were looking for indications of regulated IAA formation from tryptophol in systems containing nondisrupted cell structures. Suspensions of unicellular plants and sections of multicellular plants were supplied with a large excess of tryptophol. In the absence of regulatory mechanisms, this might reasonably be expected to lead to drastically enhanced IAA levels. However, the majority of plants examined did not accumulate substantial amounts of 2 Abbreviations: tryptophol, indole-3-ethanol or 3-(2-hydroxyethyl)indole; Ve, elution volume.The most abundant tryptophol metabolites in bacteria, thallophytes, and seed plants were conjugates: esters and glycosides.MATERIALS AND METHODS Instrumentation. 'H NMR spectra were recorded at 100 MHz on a JEOL FX-100 Fourier-transform spectrometer. Chemical shifts (a) were recorded relative to tetramethylsilane. GC-MS was on a Hewlett-Packard 5985a instrument, using helium at 30 ml/ min as the carrier gas and electron impact ionization at 70 ev. Columns and temperature pr...

show abstract

“…The content of the auxin tentatively identified as IAA (Eliasson 1969) is high in growing aspen shoots both in light and in the dark as compared with values repotted in literature for other species (Rajagopal 1967). The auxin content in dark-grown material varied considerably for different samples and tended to be lower in older than in younger shoots.…”

Section: Discussionmentioning

confidence: 51%

Growth Regulators in Populus tremula

Eliasson

1971

Physiologia Plantarum

View full text Add to dashboard Cite

Shoots grown out from aspen root sections in light or in darkness were extracted and the content of growth‐regulating substances in various fractions was determined with the Avena coleoptile straight‐growth assay. The most obvious difference was obtained for the inhibitor β fraction. This was about ten times more active in the light‐grown than in the dark‐grown shoots. Some indications of more growth inhibitory material in ether‐insoluble fractions of light‐grown plants were also obtained. The stimulation obtained at the Rf of indol‐3‐yl‐acetic acid was somewhat lower in the etiolated shoots than in the light‐grown ones.

show abstract

Metabolism of Indole‐3‐acetaldehyde.

Cited by 29 publications

References 16 publications

Occurrence and Metabolism of Indoleacetaldehyde in Certain Higher Plant Tissues Under Aseptic Conditions

Occurrence and Metabolism of Indoleacetaldehyde in Certain Higher Plant Tissues Under Aseptic Conditions

Metabolism of Tryptophol in Higher and Lower Plants

Growth Regulators in Populus tremula

Contact Info

Product

Resources

About