[Comparative study of the formation and biogenesis of beta-indoleacetic acid by Agrobacterium tumefaciens and its fixed L forms].
Explore the source record for details and available documents.
SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Levels of 5-hydroxyindoleacetic acid, indoleacetic acid and total indoles were determined in the urine of 23 patients with systemic scleroderma and 7 patients with cutaneous scleroderma, before and after peroral loading with L-tryptophan (0-1 g/kg body weight). Before loading, 5-hydroxyindoleacetic acid levels were normal in nearly all cases of systemic scleroderma as well as of cutaneous scleroderma; however after loading, in nearly one half of cases there was no normal increase of this metabolite. These results suggest impaired transformation of serotonin into 5-hydroxyindoleacetic acid. A disproportionately high ratio of total indoles to indoleacetic acid suggests the presence of excess of tryptamine. The results of the study may indicate that in scleroderma metabolism of biogenic amines derived from tryptophan is abnormal, probably as a result of impaired activity of monoamine oxidase.
The phytopathogen Pseudomonas syringae subsp. savastanoi incites the production of galls on olive and oleander plants. Gall formation is dependent upon the bacterial synthesis of the phytohormone indole-3-acetic acid (IAA). Strains isolated from oleander galls are capable of further metabolizing IAA to an amino acid conjugate, 3-indoleacetyl-epsilon-L-lysine (IAA-lysine); bacterial olive gall isolates lack this activity. In this study, the cloned gene for IAA-lysine synthetase (iaaL+) was introduced into strains isolated from olive and oleander galls to determine its effect on the regulation of IAA pool size and virulence. IAA-lysine was synthesized by isolates from olive galls when iaaL+ was introduced by conjugation, but the amount of IAA which accumulated in culture by the transconjugant was reduced by one-third. When the iaaL+ locus of an oleander gall isolate was inactivated by Tn5 mutagenesis, the resulting mutant did not convert IAA to IAA-lysine; however, it accumulated fivefold more IAA in culture than the wild type did. When inoculated into oleander plants, the iaaL mutant did not cause typical gall symptoms, nor did it replicate within host tissue similarly to the wild type.
Floating Avena sativa L. cv Victory coleoptile segments were used to determine whether the straight-growth indoleacetic acid (IAA) assay can be reconciled with the Avena curvature assay and the Cholodny-Went theory of photo- and gravitropism. Measurements of segment length after 5 h yield sigmoid-shaped IAA dose-response curves with the growth rate leveling off at 1 [mu]M. However, measurements made at 24 h generate bell-shaped curves with maximal growth being induced by 10 [mu]M IAA. The difference between short- and long-term IAA dose-response curves is not due to IAA degradation; instead, it is the result of two growth responses to IAA. The initial one is rapid, responds to low concentrations of IAA, and lasts for 12 h. The second response is less sensitive to IAA than the first one. It appears after 6 h but is not obvious until the last 12 h of a 24-h incubation. The profile of short-term IAA dose-response curves reflects the initial growth response, whereas that of the 24-h curve is the sum of both growth responses. Linear-linear plots of 5- and 24-h dose-response curves show that coleoptile segment growth rate is proportional to IAA concentration up to 0.3 [mu]M. When the efficiency of IAA action is taken into account, it is found that the most effective IAA concentration for short and long incubations is 0.4 [mu]M. It is concluded that the Avena straight-growth IAA assay is as sensitive as the Avena coleoptile curvature assay, and that it is consistent with the Cholodny-Went theory.
The amino-acid precursors tryptophan and tyrosine, and the major metabolites 5-hydroxyindoleacetic acid, indoleacetic acid, homovanillic acid and 3-methoxy-4-hydroxyphenethyleneglycol, related to the central neurotransmitters serotonin, dopamine and norepinephrine, were measured in 62 samples of cerebrospinal fluid from human neonates. Means are reported for the samples from 17 medically uncomplicated infants and for the larger group (42 to 45) of infants with medical complications. The latter group was divided according to diagnosis and medication. All groups had significantly higher levels of all compounds in comparison with older children and adults. There were few significant subgroup differences in the group with complications. In both the normal and complicated groups a number of significant correlations were observed between the compounds themselves and with other physiological measures.
Four chemicals--gibberellic acid, indoleacetic acid, 2,4-6 and thiouracil were tested for their inhibitory effect against a virus disease of Vigna sinensis (cowpea). All the four chemicals inhibited the virus to a considerable extent in in vitro studies. Pre and post-inoculation treatments were equally effective in inhibiting the virus, viz. local lesion formation on Chenopodium amaranticolor leaves. The level of inhibition subsequently decreased with lower concentration of the chemicals. Seed soaking in the chemicals controlled the virus infection.
Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid. Indoleacetic acid (IAA), 4-chloro-IAA (4-Cl-IAA), and 5-Cl-IAA were metabolized to different extents by strains 61A24 and 110. Metabolites were isolated and analyzed by high-performance liquid chromatography and conventional mass spectrometry (MS) methods, including MS-mass spectroscopy, UV spectroscopy, and high-performance liquid chromatography-MS. The identified products indicate a novel metabolic pathway in which IAA is metabolized via dioxindole-3-acetic acid, dioxindole, isatin, and 2-aminophenyl glyoxylic acid (isatinic acid) to anthranilic acid, which is further metabolized. Degradation of 4-Cl-IAA apparently stops at the 4-Cl-dioxindole step in contrast to 5-Cl-IAA which is metabolized to 5-Cl-anthranilic acid.
A carrot (Daucus carota, L.) genomic clone (DcPRP1) was isolated on the basis of its homology to previously described cDNAs encoding a wound-inducible, proline-rich cell wall protein. DNA sequence analysis showed that DcPRP1 contains a single open-reading frame encoding a 235-amino acid protein that is colinear with that predicted from the cDNA sequence with the exception of four amino acids at the N terminus and a 60-nucleotide insertion present within the genomic clone. Genomic Southern hybridization analysis showed that the cloned sequence hybridized with a single restriction enzyme fragment using several restriction enzymes. Primer extension and northern hybridization analysis indicated that the expression of DcPRP1 is developmentally regulated and linked to the formation of storage roots, where this gene is expressed at high levels after wounding. The level of DcPRP1 mRNA was greatest in tissue immediately adjacent to the wound site. Treatment of unwounded carrot storage roots with 10 microM 2,4-dichlorophenoxy-acetic acid, indoleacetic acid, or naphthalene-1-acetic acid also resulted in the accumulation of DcPRP1 transcripts to a level equal to that seen in wounded tissue.
Nystatin, riboflavin, ascorbic acid, captan, indoleacetic acid, and colchicin were tested in two concentrations for their effect on the oxygen uptake of the spores of Mucor racemosus, Cladosporium tenuissimum, Cochliobolus spicifer, and Macrophomina phaseoli. Nystatin and captan inhibited the oxygen uptake of the spores of all fungi used, and this inhibitory effect increases with increasing concentration. On the other hand, riboflavin, ascorbic acid, indoleacetic acid, and colchicin were found to have a stimulating effect. Increasing the concentration of these medicaments to the double concentration causes a decrease in the oxygen uptake, except in the case of ascorbic acid where the reverse occurs.
A new method for the determination of tryptophan and its metabolites in a single mouse brain using high-performance liquid chromatography (HPLC) with fluorometric detection is described. Tryptophan, serotonin, 5-hydroxyindoleacetic acid, indoleacetic acid, and tryptophol were clearly separated by a C8 reverse-phase column. Tissue preparation is performed only to centrifuge homogenates of brain prior to the injection to HPLC. The sensitivity is in the range from 10 to 15 pg.
Maternal and umbilical foetal blood at delivery were analysed for tryptophan metabolites by using fully automated high-performance liquid chromatography. The metabolites detected in 100 microliters of maternal plasma were kynurenine, serotonin, 5-hydroxyindoleacetic acid, indolelactic acid, indoleacetic acid and indolepropionic acid. These metabolites were present in various amounts in the protein-bound form. Except for indolepropionic acid, the concentrations of tryptophan metabolites were significantly higher in umbilical foetal plasma than in maternal plasma. In addition, 3-hydroxyanthranilic acid was present in umbilical foetal blood, but not in maternal blood. Furthermore, kynurenic acid was also detected in amniotic fluids.
An automated high-performance liquid chromatographic method that incorporates direct injection of biological samples followed by chromatographic sample clean-up in a precolumn is described for the determination of tryptophan and its metabolites in human plasma and serum. The system gave reproducible data with a coefficient of variation of less than 3% with a sample size of 100 microliters of human plasma. The major tryptophan metabolites found in 100 microliters of human plasma were kynurenine, indolelactic acid, indoleacetic acid, indolepropionic acid, serotonin and 5-hydroxyindoleacetic acid. The level of tryptophan and kynurenine in individuals was constant in comparison with other metabolites. Analysis of samples from normal controls, diabetics, gravida and their foetuses showed a tendency for tryptophan metabolites to be low in maternal plasma.