[Kinetics studies of endogenous abscissic acid (ABA) and indoleacetic acid (IAA) in ripening seeds of Phaseolus vulgaris L. (proceedings)].
Explore the source record for details and available documents.
Abscisic Acid↗
SEARCH · PubMed Health
Results for “Indoleacetic Acids”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Effects of 2,4,5-trichlorophenoxyacetic acid and quinolinic acid on 5-hydroxy-3-indoleacetic acid transport by the rabbit choroid plexus: pharmacology and electron microscopic cytochemistry.
2,4,5-Trichlorophenoxyacetic acid (2,4,5-T) reduced the uptake of 5-hydroxy-3-indoleacetic acid (5-HIAA) by the choroid plexus in a dose-related manner, while treatment with quinolinic acid at comparable concentrations did not inhibit 5-HIAA uptake. The role of carrier-mediated transport in the clearance of 5-HIAA from cerebrospinal fluid (CSF) was also evaluated in vivo by ventriculocisternal perfusion. Steady-state clearance of 5-HIAA from CSF exceeded that of inulin and was reduced competitively in the presence of 2,4,5-T. However, the clearance was not affected by quinolinic acid. The effect of 2,4,5-T on transport enzyme systems was also studied by electron microscopic cytochemistry. Na+-K+-ATPase and cytochrome oxidase activities in the choroid plexus were reduced by 2,4,5-T. Since this transport system in the choroid plexus is normally responsible for the excretion of the serotonin metabolite from the brain to the plasma, accumulation of endogenously produced organic acids in the CSF and the brain, secondary to reduced clearance by the choroid plexus, could be a contributing factor in the development of neurotoxicity.
2,4,5-Trichlorophenoxyacetic Acid↗
Formation of indoleacetic acid by intestinal anaerobes.
Indoleacetic acid was produced from tryptophan by only three of 23 intestinal anaerobes studied. Evidence is presented to show that the formation of indoleacetic acid proceeds through the intermediate, indolepyruvic acid, via transamination with alpha-ketoglutarate rather than by tryptamine pathway.
Anaerobiosis↗
Aromatic aminotransferase activity and indoleacetic acid production in Rhizobium meliloti.
Bacterial indoleacetic acid (IAA) production, which has been proposed to play a role in the Rhizobium-legume symbiosis, is a poorly understood process. Previous data have suggested that IAA biosynthesis in Rhizobium meliloti can occur through an indolepyruvate intermediate derived from tryptophan by an aminotransferase activity. To further examine this biosynthetic pathway, the aromatic aminotransferase (AAT) activity of Rhizobium meliloti 102F34 (F34) was characterized. At least four proteins were detected on nondenaturing gels of F34 protein extracts that exhibited AAT activity. All four of these AATs were constitutively produced and utilized the aromatic amino acids tryptophan, phenylalanine, and tyrosine as amino substrates. Two AATs were also capable of using aspartate. Plasmids from an F34 gene bank were identified that coded for the synthesis of at least three of these proteins, and the respective gene sequences were localized by transposon mutagenesis. Selected transposon insertions were recombined into the F34 genome to produce strains defective in two of these proteins (AAT1 and AAT2). Characterization of the mutants revealed that neither was essential for the biosynthesis of IAA in the absence of exogenous tryptophan, but that both contributed to IAA biosynthesis when high levels of exogenous tryptophan were present. AAT1 and AAT2 were also not required for the production of a minimal level of aromatic amino acids, but both were able to scavenge nitrogen from the aromatic amino acids during nitrogen deprivation. Neither AAT1 nor AAT2 was essential for symbiosis with alfalfa.
Cloning, Molecular↗
Cotranscription of genes encoding indoleacetic acid production in Pseudomonas syringae subsp. savastanoi.
Indoleacetic acid (IAA) production by the plant pathogen Pseudomonas syringae subsp. savastanoi is essential for tumor formation on olive and oleander. The bacterium produces IAA from tryptophan in reactions catalyzed by tryptophan monooxygenase and indoleacetamide hydrolase. The genetic determinants are, respectively, iaaM and iaaH. In oleander isolates, the genes encoding the IAA biosynthetic enzymes are located on a plasmid; in olive isolates, the genes occur on the chromosome. The IAA genes from the oleander isolate strain EW2009 are located within a 4-kilobase (kb) segment of the 52-kb plasmid pIAA1. Escherichia coli strains harboring a recombinant plasmid, pCJP3, which contains this 4-kb fragment, excreted IAA into culture media, and crude cell extracts had both tryptophan monooxygenase and indoleacetamide hydrolase activity. In vitro coupled transcription-translation of pCJP3 demonstrated that this fragment coded for proteins of 62 and 47 kilodaltons which correspond to tryptophan monooxygenase and indoleacetamide hydrolase, respectively. Expression of these genes was dependent upon a vector promoter in pCJP3. However, in the absence of a vector promoter, E. coli containing recombinant plasmids with additional pIAA1 DNA in front of iaaM had high levels of tryptophan monooxygenase. Northern (RNA) hybridization experiments verified that iaaM and iaaH are cotranscribed as a portion of a ca. 4- to 5-kb transcript in vivo. Southern hybridization experiments with IAA plasmids from different oleander strains of P. syringae subsp. savastanoi revealed that all IAA plasmids contained a region of at least 10 kb of homology, with the IAA genes at one end. Repetitive DNA and a copy of IS51 were found at the end of this region of homology.
Amidohydrolases↗
Simultaneous liquid chromatographic determination of vanillylmandelic acid, homovanillic acid, and 5-hydroxy-3-indoleacetic acid in urine, using isocratic elution and electrochemical detection.
A method for the simultaneous measurement of vanillylmandelic acid, homovanillic acid and 5-hydroxyindoleacetic acid in urine is described. Based on reversed-phase liquid chromatography with electrochemical detection, the procedure employs isocratic elution, thus making it suitable for use in the less well-equipped clinical or research laboratory. A simple extraction of the acids from acidified urine into ethyl acetate, is followed by evaporating to dryness a portion of the organic layer, and redissolving the residue in chromatographic mobile phase. Up to 20 samples can be analysed in a single working day. The method is validated and the results obtained are compared with reference methods. The cause of contamination of the glassy carbon surface of the working electrode is investigated, and a simple electrochemical pretreatment is described that overcomes this problem. Finally, the extra clinical information that can be derived from multi-metabolite assays is considered.
Biogenic Amines↗
Action of cerebral ischemia on decreased levels of 3-methoxy-4-hydroxy-phenylethylgylcol sulfate, homovanillic acid and 5-hydroxy-indoleacetic acid produced by pargyline.
Explore the source record for details and available documents.
3-Methoxy-4-hydroxyphenylethanol↗
[Homovanillic acid and 5--hydroxy-indoleacetic acid in the cerebrospinal fluid of man--concentration gradients between lumbar and ventricular CSF and variations in ventricular CSF-- (author's transl)].
Explore the source record for details and available documents.
Adolescent↗
Indoleacetic acid operon of Pseudomonas syringae subsp. savastanoi: transcription analysis and promoter identification.
Expression of the indoleacetic acid (iaa) operon, which contributes to the virulence of the phytopathogenic bacterium Pseudomonas syringae subsp. savastanoi, was monitored by using broad-host-range lacZ reporter gene plasmids. A combination of translational (gene) fusions and transcriptional (operon) fusions of P. syringae subsp. savastanoi sequences to lacZ allowed localization of the iaa operon promoter. RNA recovered from P. syringae subsp. savastanoi strains was mapped with iaa operon-specific probes to precisely locate the transcription initiation site. When transcripts from an iaaM::lacZ fusion in Escherichia coli were analyzed, an identical transcription initiation site was observed. The DNA sequence of the iaa operon promoter closely resembled the consensus E. coli promoter sequence. We detected an active, constitutive level of indoleacetic acid biosynthetic gene expression during bacterial growth under a variety of conditions in the absence of host plant influence.
Base Sequence↗
Binding and functional properties of concanavalin A and its derivatives. III. Interactions with indoleacetic acid and other hydrophobic ligands.
The binding of concanavalin A to various structures via hydrophobic interactions has been studied using a variety of physicochemical assays. It was found that concanavalin A binds to nonpolar compounds such as the plant auxin beta-indoleacetic acid and its structural analogue tryptophan and that this binding is independent of the saccharide-binding activity normally associated with the lectin. The results of equilibrium dialysis experiments on the binding of beta-indoleacetic acid were consistent with the presence of a single weak binding site per subunit of protein, having an association constant of about 7 X 10(2) M-1. Competition experiments using various nonpolar compounds such as o-iodobenzoic acid suggested that this hydrophobic binding site is located in the same cavity which binds the iodine-containing ligand as shown by x-ray crystallography. Concanavalin A also binds to lipid vesicles composed of dipalmitoylphosphatidylcholine or 12-O-tetradecanoyl phorbol-13-O-acetate. This binding to lipid membranes raises the possibility that the synergistic effects of concanavalin A and tetradecanoyl phorbol acetate on lymphocyte mitogenesis may be due in part to an interaction between lectin and the phorbol ester.
Concanavalin A↗
Fluorescence polarization immunoassay of urinary 5-hydroxy-3-indoleacetic acid.
Fluorescence polarization immunoassay of 5-hydroxy-3-indoleacetic acid in urine is described and compared with liquid chromatography (electrochemical detection) and colorimetry. Reports of in-house performance data and results of clinical trials are included to emphasize the usefulness of the assay for routine work.
Chromatography, High Pressure Liquid↗
Altered ruminal microbiome tryptophan metabolism and their derived 3-indoleacetic acid inhibit ruminal inflammation in subacute ruminal acidosis goats.
BACKGROUND: Subacute ruminal acidosis (SARA) is a digestive disorder that often severely jeopardizes the health and lactation performance of ruminants fed a high-energy diet. Different dairy ruminants exhibit varying degrees of inflammation accompanied by variations in the rumen microbiota when SARA occurs. Our understanding of the occurrence of SARA and varying degrees of rumen epithelial inflammation is lacking. Hence, we performed rumen metagenomic, metagenome-assembled genome and metabolomic analyses, with transcriptome and single-nucleus RNA sequence analyses, to explore the microbial mechanism of SARA occurrence and different degrees of inflammation. RESULTS: A total of 36 goats fed two diets with gradually increasing levels of rumen-degradable starch (RDS) were included in this study, and SARA goats fed 70% concentrate diets supplemented with whole corn (HGW-SARA) and SARA goats fed 70% concentrate diets supplemented with crushed corn (HGC-SARA) were identified. Moreover, 11 goats fed a control basal diet, named LGW-CON, were also included. Compared with those in the LGW-CON group, the rumen fermentation capacity was enhanced, accompanied by ruminal epithelial and systemic inflammation, in goats from HGW-SARA and HGC-SARA. Between them, HGC-SARA goats presented less inflammation. Notably, the ruminal inflammation-related pathways were increased only in the HGW-SARA group but not in the HGC-SARA group. Metagenomic analysis revealed that the β diversity of SARA goats was significantly different from that of LGW-CON goats. Ruminococcus significantly increased in both SARA groups, whereas Prevotella and Bacteroidales significantly decreased, which was accompanied by a decrease in cellulose and hemicellulose enzymes and an increase in lysozymes and lipopolysaccharide synthesis enzymes. Multi-omics analysis of the ruminal contents and tissues suggested that epithelial inflammation was caused by disturbed ruminal microbiome-induced Th17 cell differentiation and IL-17 signalling pathway activation. Comparative analyses between the HGW-SARA and HGC-SARA groups highlighted the importance of Selenomonas and Bifidobacterium, as well as bacterial tryptophan metabolism, in the production of 3-indoleacetic acid, which mitigated ruminal epithelial inflammation by modulating Th17 cells and inhibiting IL-17 signalling. Ruminal microbiota transplantation from HGW-SARA goats to healthy dairy goats and mice revealed the role of microbes in epithelial inflammation. Additionally, 3-indoleacetic acid supplementation reduced rumen inflammation and the IL-17 concentration in the serum, improved VFAs absorption, and enhanced milk production. CONCLUSIONS: This study unveiled that after SARA was induced by high-concentrate feeding, the rumen homeostasis was disrupted, and rumen fiber degradation capacity of dairy goats decreased, but the LPS synthesis capacity increased, and inflammation of the rumen epithelium was observed. However, the ruminal microbial species from the Bifidobacterium and Selenomonas genera and bacterial 3-indole acetic acid are pivotal in mitigating ruminal epithelial inflammation during SARA in dairy goats. This could potentially be attributed to the modulation of ruminal Th17 cell proportions and the inhibition of IL-17 signalling pathways. Video Abstract.
Rumen↗
Effect of beta-indoleacetic acid on RNA and protein synthesis in Escherichia coli.
The effect of different concentrations of beta-indoleacetic acid (IAA) on RNA and protein synthesis and the stability of associations of E. coli ribosomes at 3 mM Mg2+ was investigated. IAA in a concentration of 100 microgram/ml had a slight stimulatory effect on the incorporation of [14C]leucine into proteins and stimulated the incorporation of [14C]uracil into the RNA of intact cells more noticeably. In the presence of 2500 microgram/ml of the auxin RNA synthesis was inhibited by 65% and protein synthesis by 40-50% as compared to the control. In a cell-free system containing poly(U) IAA in concentrations of 10-100 microgram/ml increased polyphenylalanine synthesis by an average of 30%, while at high concentrations IAA noticeably inhibited its synthesis. It was found that the proportion of stable ribosomes in lysates obtained from cells incubated with IAA in concentrations of 250 and 1000 microgram/ml decreased to 18 and 3%. It is suggested that the inhibition of protein synthesis in E. coli by IAA is due to inhibition of the initiation of translation.
Bacterial Proteins↗
Influence of 3-indoleacetic acid on cytochemical changes in nuclei and cytoplasm of human fibroblasts in the cell culture.
The performed studies covered the action of 3-indoleacetic acid (3IAA) on human fibroblasts cultured in vitro. The 3IAA implemented in the studies was provided by Chemapol Firm (Czechoslovakia). All the investigations were carried out on I passage fibroblasts, taken from the human skin in form of monolayer culture. Feulgen's method and autographic one were resorted to in the studies. The optimal time of acid hydrolysis was 10 min. Quantitative measurements of DNA in nuclei of fibroblasts were done on integrating cytophotometer. Incubation with labelled 3H uridine as RNA precursor was employed for demonstrating the activity of cell nucleus transcription. As concerns the quantitative changes in nucleic acids, it was disclosed that DNA and RNA synthesis was intensified. Nuclei were seen to appear with polydiploidal DNA amount in cultures being influenced by 3IAA action. The smallest number of mitoses was revealed in the cultures exposed to the action of the highest dose of the said compound. Stronger 3H uridine incorporation was recorded in cultures 24 and 72 hours after the administration of 10 mg/1000 ml of 3IAA. The results were presented in the form of diagrams, nucleinogram and tables.
Adult↗
Assay for the enzymatic conversion of indoleacetic acid to 3-methylindole in a ruminal Lactobacillus species.
An assay to measure the rate of enzymatic formation of 3-methylindole (3MI) from indoleacetic acid (IAA) in Lactobacillus sp. strain 11201 was developed. The reaction mixture contained 50 micrograms of microbial protein per ml (range, 25 to 100 mg/ml), essential low-molecular-weight reaction ingredients, and radiolabeled IAA as substrate (range, 0 to 2 mM IAA). The reaction was anaerobic for 25 min at 39 degrees C. The apparent Michaelis-Menten constants were: Km, 0.14 mM IAA; and Vmax, 64 nmol 3MI.mg-1.min-1. The inhibitors avidin, aminopterin, and EDTA had no effect on the 3MI-forming enzyme. Dithionite stimulated the 3MI-forming enzyme. The product of the reaction, 3MI, acted as a noncompetitive inhibitor of the enzyme. Enzyme activity was associated with the cell wall fraction after sonication; treatment with the French press; or treatment with detergents, proteolytic enzymes, and EDTA.
Animals↗
Transport of 5-hydroxy-3-indoleacetic acid by spinal cord during subarachnoid perfusion.
The transport of [14C]5-hydroxy-3-indoleacetic acid (5-HIAA) by the spinal cord was investigated with spinal subarachnoid perfusions of 20 rhesus monkeys. For spinal white matter, [14C]5-HIAA was found to distribute in a tissue space of 50-55% and to exchange readily between tissue and blood across parenchymal capillaries. The data were analyzed with a model of the spinal cord as a cylinder and a mean capillary transfer half-time of 20 min determined. The spinal cord cleared [14C]5-HIAA from 19 mul/min of CSF. Administration of probenecid yielded a somewhat lower mean tracer clearance rate (14 mul/min) but did not alter the capillary exchange half-time or the distribution volume of [14C]5-HIAA in the spinal cord. The data suggest that capillaries within spinal white matter transport 5-HIAA by a mechanism which is insensitive to inhibition by probenecid and that lumbar CSF concentrations reflect only a small portion of total 5-HIAA production by the central nervous system.
Animals↗
Occurrence of 5-hydroxy-3-indoleacetic acid in urine from several animal species.
1. The normal levels of 5-hydroxy-3-indoleacetic acid (5HIAA) were determined in the urine of four species of laboratory animals (dog, rabbit, rat and guinea-pig). 2. When 5HIAA excretion was calculated as mg/24 h, the output in the four species was in the order of rabbit greater than dog greater than guinea-pig greater than rat; but when it was calculated as mu/mg of creatinine, the order was guinea-pig greater than rabbit greater than rat greater than dog. 3. There were significant differences in the excretion of urinary 5HIAA between males and females within two species: rats and dogs.
Animals↗
Hill-acitivity and P700 concentration of chloroplasts isolated from radish seedlings treated with-indoleacetic acid, kinetin of gibberellic acid.
The Hill-activity (reduction of DCPIP or methylviolgen) and the concentration of P700 were studied in chloroplasts isolated from cotyledons of radish seedlings (Raphanus sativus L. saxa Treib), which had been grown with the addition of beta-indoleacetic acid (IAA), kinetin, or gibberellic acid. 1) The photosynthetic activity of young chloroplasts from 3 day old Raphanus seedlings is very high (c. 180 micron mol O2/mol chlorophyll X h) and decreases continuously thereafter with increasing age. The steady state Hill-activity is reached after 8 to 10 days (values of 55 to 50 micron mol O2/mg chlorophyll X h). 2) Chloroplasts from plants treated with IAA or kinetin not only exhibit higher plastoquinone levels 1,2, but also a higher P700-content and a higher Hill-activity. The promotion effect is more pronounced with kinetin (+36 tb 40%) than with IAA (+12 to 17%). 3) Gibberellic acid has a different effect on composition and activity of chloroplasts. In younger seedlings the Hill-activity appears to be somewhat stimulated, without promotion effect on plastoquinone 2 or P700 concentration. After 10 days GA3-treated plants show signs of chlorosis combined with a strong decrease in photosynthetic activity. 4) The data clearly demonstrate that the composition and activity of the photosynthetic apparatus are under phytohormone control. IAA and even better kinetin promote the light induced formation of pigment systems and electrontransport chains. GA3 seems to block the rebuilding of the photosynthetic apparatus under steady state conditions.
2,6-Dichloroindophenol↗