BIOSYNTHESIS OF MUSTARD OIL GLUCOSIDES: VII. FORMATION OF SINIGRIN IN HORSERADISH FROM HOMOMETHIONINE-2-14C AND HOMOSERINE-2-14C

1966 ◽  
Vol 44 (12) ◽  
pp. 1625-1632 ◽  
Author(s):  
M. D. Chisholm ◽  
L. R. Wetter
Keyword(s):  
Amino Acids ◽  
Allyl Isothiocyanate ◽  
Valeric Acid ◽  
The Other ◽  
Mustard Oil ◽  
Armoracia Lapathifolia ◽  
Hydroxyvaleric Acid

Five 14C-labeled amino acids were administered to horseradish (Armoracia lapathifolia Gilib.) leaves. Three of the amino acids, DL-homoserine-2-14C, DL-methionine-2-14C, and DL-homomethionine-2-14C (2-amino-5-(methylthio)-valeric acid), were precursors of the aglycone (allyl isothiocyanate) of sinigrin. The other two, DL-allylglycine-2-14C (2-amino-4-pentenoic acid) and DL-2-amino-5-hydroxyvaleric acid-2-14C, were incorporated in insignificant amounts. The relationships of the three efficient precursors are discussed. The syntheses of four 14C-labeled amino acids used in this investigation are described.

BIOSYNTHESIS OF MUSTARD OIL GLUCOSIDES: I. ADMINISTRATION OF C14-LABELLED COMPOUNDS TO HORSERADISH, NASTURTIUM, AND WATERCRESS

1962 ◽  
Vol 40 (1) ◽  
pp. 1505-1514 ◽  
Author(s):  
E. W. Underhill ◽  
M. D. Chisholm ◽  
L. R. Wetter
Keyword(s):  
Allyl Isothiocyanate ◽  
The Other ◽  
Mustard Oil ◽  
Methyl Carbon ◽  
Nasturtium Officinale ◽  
Other Hand ◽  
Tropaeolum Majus ◽  
Armoracia Lapathifolia ◽  
Carboxyl Carbon

Biosynthetic investigations with C14-labelled compounds indicate that the aromatic isothiocyanate moieties of mustard oil glucosides obtained from garden nasturtium (Tropaeolum majus L.) and watercress (Nasturtium officinale R.Br.) are derived from phenylalanine. Similar investigations on sinigrin, the mustard oil glucoside isolated from horseradish (Armoracia lapathifolia Gilib.) demonstrate that glycine is incorporated into allyl isothiocyanate. The methyl carbon of acetate was readily incorporated into sinigrin and gluconasturtium and was found almost exclusively in the 'isothiocyanate carbon'; on the other hand the carboxyl carbon is a poor precursor of sinigrin.

BIOSYNTHESIS OF MUSTARD OIL GLUCOSIDES: I. ADMINISTRATION OF C14-LABELLED COMPOUNDS TO HORSERADISH, NASTURTIUM, AND WATERCRESS

1962 ◽  
Vol 40 (11) ◽  
pp. 1505-1514 ◽  
Author(s):  
E. W. Underhill ◽  
M. D. Chisholm ◽  
L. R. Wetter
Keyword(s):  
Allyl Isothiocyanate ◽  
The Other ◽  
Mustard Oil ◽  
Methyl Carbon ◽  
Nasturtium Officinale ◽  
Other Hand ◽  
Tropaeolum Majus ◽  
Armoracia Lapathifolia ◽  
Carboxyl Carbon

Biosynthetic investigations with C14-labelled compounds indicate that the aromatic isothiocyanate moieties of mustard oil glucosides obtained from garden nasturtium (Tropaeolum majus L.) and watercress (Nasturtium officinale R.Br.) are derived from phenylalanine. Similar investigations on sinigrin, the mustard oil glucoside isolated from horseradish (Armoracia lapathifolia Gilib.) demonstrate that glycine is incorporated into allyl isothiocyanate. The methyl carbon of acetate was readily incorporated into sinigrin and gluconasturtium and was found almost exclusively in the 'isothiocyanate carbon'; on the other hand the carboxyl carbon is a poor precursor of sinigrin.

Sources of sulfur in the thioglucosides of various higher plants

1968 ◽  
Vol 46 (8) ◽  
pp. 931-935 ◽  
Author(s):  
L. R. Wetter ◽  
M. D. Chisholm
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Higher Plants ◽  
Carbon Skeleton ◽  
The Other ◽  
Nasturtium Officinale ◽  
Tropaeolum Majus ◽  
Armoracia Lapathifolia

L-Methionine-35S and DL-cysteine-35S were good sources of sulfur for the biosynthesis of sinigrin in Armoracia lapathifolia Gilib. and were incorporated with approximately the same efficiency. Homomethionine-35S was a slightly poorer source of sulfur than methionine, while taurine-35S was a very poor source. When homomethionine, methionine, and cysteine were employed as sources of sulfur, the distribution of radioactivity between the two sulfur atoms in sinigrin was approximately 80% in the isothiocyanate moiety and 10–15% in the sulfate moiety. When taurine was employed, the distribution was reversed. 1-Thio-β-D-glucose (1-thioglucose) also was a poor source of sulfur for sinigrin. The carbon skeleton of 1-thioglucose was only slightly incorporated into this thioglucoside. The experiments indicated that 1-thioglucose was not a direct precursor of the 1-thioglucosyl residue of sinigrin.The administration of doubly labeled methionine-2-14C-35S clearly demonstrated that this amino acid was not incorporated intact into sinigrin. The carbon-2 and sulfur atoms were metabolized by two different routes.Preliminary studies related to sulfur incorporation into the thioglucosides of Nasturtium officinale R.Br., Tropaeolum majus L., and Reseda luteola L. indicated that there were some differences depending on the source of sulfur; DL-cysteine was a better source of sulfur than either methionine or 1-thioglucose. Tropaeolum majus L. appeared to utilize the sulfur of cysteine for the production of thioglucoside as efficiently as Armoracia lapathifolia Gilib.; however, the other two species utilized the sulfur from the amino acids very poorly.

BIOSYNTHESIS OF MUSTARD OIL GLUCOSIDES: IV. THE ADMINISTRATION OF METHIONINE-C14 AND RELATED COMPOUNDS TO HORSERADISH

1964 ◽  
Vol 42 (7) ◽  
pp. 1033-1040 ◽  
Author(s):  
M. D. Chisholm ◽  
L. R. Wetter
Keyword(s):  
Degradation Products ◽  
Allyl Isothiocyanate ◽  
Chemical Degradation ◽  
Mustard Oil ◽  
Methyl Group ◽  
Armoracia Lapathifolia ◽  
Related Compounds

The administration of C14-labelled compounds to horseradish (Armoracia lapathifolia Gilib.) demonstrated that both methionine and acetate were efficiently incorporated into the aglycone (allyl isothiocyanate) of sinigrin. Chemical degradation of the aglycone showed that the methyl group of acetate appeared in the "isothiocyanate carbon" and that carbons 2, 3, and 4 of methionine were incorporated into carbons 2, 3, and 4 respectively of the aglycone with very little randomization. Homocysteine was the only other compound that was incorporated into the aglycone. Other degradation products of methionine did not appear to be incorporated into allyl isothiocyanate.

scholarly journals Comparison of the efficiency of proteins contained in lucerne hay and soya-bean meal for sheep

1969 ◽  
Vol 23 (3) ◽  
pp. 455-470 ◽  
Author(s):  
H. Tagari
Keyword(s):  
Amino Acids ◽  
Volatile Fatty Acids ◽  
Sole Source ◽  
Soya Bean ◽  
Valeric Acid ◽  
The Other ◽  
Triphenyltetrazolium Chloride ◽  
Bean Meal ◽  
Soya Bean Meal

1. In four feeding experiments with sheep the utilization of proteins contained in lucerne hay and of those in toasted soya-bean meal (SBM), representing a roughage and concentrate feed respectively, were examined. The ration of one group of animals contained lucerne hay as sole source of digestible protein and that of the other SBM.2. Measurements of the nitrogen balance showed clearly the superiority of lucerne hay as protein source compared with soya-bean meal; this arose from the greater N retention found with the lucerne hay ration.3. The influence of both rations on the metabolic pathways of the proteins was examined by following the changes of concentration of various metabolites in the rumen contents and of blood urea at different intervals after feeding.4. Concentrations of urea found in the blood of the sheep given lucerne hay were lower than those of the other group, a finding which is in agreement with the results of the balance experiments.5. The concentrations of NH2-N and of aminoacids in the rumen liquor were higher in sheep given lucerne hay than in those given SBM. These concentrations appeared to be related to the differences between the soluble non-protein N contents of the two feeds.6. The results agree with the finding from in vitro experiments that rumen liquor from sheep receiving lucerne hay promoted greater synthesis of protein than rumen liquor from sheep receiving SBM.7. Total bacterial activity as measured by the reduction of triphenyltetrazolium chloride (dehydrogenase activity) was much higher in the rumen liquor of sheep given lucerne hay than when SBM was given.8. The concentrations of volatile fatty acids (C2-C6) were much higher in the rumen liquor in sheep on the lucerne hay diet than in those on the SBM diet. After meals of the lucerne hay diet, the concentrations of acids higher than C2, particularly those of valeric acid, exceeded those present in the rumen liquor of the animals kept on the SBM diet.9. Proline and alanine appeared in relatively higher concentrations in the rumen liquor than the other amino acids determined, and these two acids together with valine disappeared very rapidly. The possible conversion of these amino acids into valeric acid is considered. It is suggested that valeric acid found in relatively high concentrations in rumen liquor of sheep given lucerne hay may be due in part to the deamination of proline, which likewise disappeared very rapidly together with alanine and valine.

Natural Vulcanization Accelerators in Hevea Latex

1948 ◽  
Vol 21 (4) ◽  
pp. 853-859
Author(s):  
R. F. A. Altman
Keyword(s):  
Amino Acids ◽  
Experimental Results ◽  
The Other ◽  
Active Nitrogen ◽  
Nitrogen Bases ◽  
Other Hand ◽  
Decomposition Processes ◽  
Volatile Products ◽  
Nitrogenous Substances ◽  
The One

Abstract As numerous investigators have shown, some of the nonrubber components of Hevea latex have a decided accelerating action on the process of vulcanization. A survey of the literature on this subject points to the validity of certain general facts. 1. Among the nonrubber components of latex which have been investigated, certain nitrogenous bases appear to be most important for accelerating the rate of vulcanization. 2. These nitrogen bases apparently occur partly naturally in fresh latex, and partly as the result of putrefaction, heating, and other decomposition processes. 3. The nitrogen bases naturally present in fresh latex at later stages have been identified by Altman to be trigonelline, stachhydrine, betonicine, choline, methylamine, trimethylamine, and ammonia. These bases are markedly active in vulcanization, as will be seen in the section on experimental results. 4. The nitrogenous substances formed by the decomposition processes have only partly been identified, on the one hand as tetra- and pentamethylene diamine and some amino acids, on the other hand as alkaloids, proline, diamino acids, etc. 5. It has been generally accepted that these nitrogenous substances are derived from the proteins of the latex. 6. Decomposition appears to be connected with the formation of a considerable amount of acids. 7. The production of volatile nitrogen bases as a rule accompanies the decomposition processes. These volatile products have not been identified. 8. The active nitrogen bases, either already formed or derived from complex nitrogenous substances, seem to be soluble in water but only slightly soluble in acetone.

METABOLISM OF AROMATIC COMPOUNDS IN HEALTHY AND RUST-INFECTED PRIMARY LEAVES OF WHEAT: II. STUDIES WITH L-PHENYLALANINE-U-14C, L-TYROSINE-U-14C, AND FERULATE-U-14C

1967 ◽  
Vol 45 (11) ◽  
pp. 2137-2153 ◽  
Author(s):  
A. Fuchs ◽  
R. Rohringer ◽  
D. J. Samborski
Keyword(s):  
Amino Acids ◽  
Stem Rust ◽  
Aromatic Compounds ◽  
The Other ◽  
Major Portion ◽  
Insoluble Residue ◽  
Resistant Reaction ◽  
Wheat Leaves

Wheat leaves infected with stem rust, especially those of susceptible plants, contained more phenylalanine and tyrosine than healthy leaves. The utilization of phenylalanine was increased in both the susceptible and resistant reaction, but the utilization of tyrosine was increased only in the susceptible reaction. No evidence of interconversion of these amino acids was obtained.In n-butanol extracts, which contained glycosides, many constituents were labelled after feeding of L-phenylalanine-U-14C. Most of the n-butanol extractives from resistant-reacting leaves contained more label than those from susceptible-reacting leaves or from healthy leaves. However, one of the n-butanol extractives from susceptible-reacting leaves was 5–10 times as active as that isolated from the other tissues.With L-phenylalanine-U-14C and ferulate-U-14C as precursors, more activity was recovered in insoluble than in soluble esters (of ferulate and p-coumarate). With L-tyrosine-U-14C as precursor, the reverse was observed. After infection, the proportion of label in insoluble esters increased more in resistant leaves than it did in susceptible leaves, regardless of the precursor used.A major portion of the activity from these precursors was recovered in the insoluble residue that contained protein and other polymers. In the experiment with L-phenylalanine-U-14C, this residue was fractionated into protein and non-hydrolyzable material. Susceptible-reacting leaves contained equal amounts of activity in these fractions, while resistant-reacting leaves incorporated 2.5 times as much activity into the non-hydrolyzable material as into protein.

scholarly journals Amino acid transport in normal and glutathione-deficient sheep erythrocytes

1976 ◽  
Vol 154 (1) ◽  
pp. 43-48 ◽  
Author(s):  
J D Young ◽  
J C Ellory ◽  
E M Tucker
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Transport ◽  
Cell Types ◽  
The Other ◽  
Acid Transport ◽  
Sheep Erythrocytes ◽  
Uptake Rates

1. Uptake rates for 23 amino acids were measured for both normal (high-GSH) and GSH-deficient (low-GSH) erythrocytes from Finnish Landrace sheep. 2. Compared with high-GSH cells, low-GSH cells had a markedly diminished permeability to D-alanine, L-alanine, α-amino-n-butyrate, valine, cysteine, serine, threonine, asparagine, lysine and ornithine. Smaller differences were observed for glycine and proline, whereas uptake of the other amino acids was not significantly different in the two cell types.

scholarly journals II. Compounds isomeric with the sulphocyanic ethers.—I. On the mustard oil of the ethyl series

1868 ◽  
Vol 16 ◽  
pp. 254-258
Keyword(s):  
Royal Society ◽  
The Other ◽  
Mustard Oil ◽  
Other Hand ◽  
Derivatives Of

The results of my researches on the chloroform-derivatives of the primary monamines, which, as I have shown, are isomeric with the nitriles, could not fail to direct my attention to allied groups of bodies, with the view of discovering similar isomerisms. In a note communicated to the Royal Society some months ago, I expressed the expectations which even then appeared to be justified in the following manner:—“In conclusion, I may be permitted to announce as everv probable the existence of a series of bodies isomeric with the sulphocyanides. Already M. Cloëz has shown that the action of chloride of cyanogen on ethylate of potassium gives rise to the formation of an ethylic cyanate possessing properties absolutely different from those belonging to the cyanate discovered by M. Wurtz. On comparing, on the other hand the properties of the methylic and ethylic sulphocyamdes with those of the sulphocyanides of allyl and phenyl, it can scarcely be doubted that we have here the representatives of two groups entirely different, and that the terms of the methyl- and ethyl-series which correspond to oil of mustard, and to the sulphocyanide of phenyl, still remain to be discovered. Experiments with which I am now engaged will show whether these bodies cannot be obtained by the action of the iodides of methyl and ethyl on sulphocyanide of silver."

Nutritional factors associated with seasonal population increase of cacao thrips, Selenothrips rubrocinctus (Giard) (Thysanoptera), on cashew, Anacardium occidentale

1963 ◽  
Vol 53 (4) ◽  
pp. 681-713 ◽  
Author(s):  
R. G. Fennah
Keyword(s):  
Amino Acids ◽  
Water Stress ◽  
Amino Acid ◽  
Acid Concentration ◽  
Leaf Tissue ◽  
The Other ◽  
Amino Acid Concentration ◽  
Population Increase ◽  
Bearing Surface ◽  
Wet Season

The feeding of the cacao thrips, Selenothrips rubrocinctus (Giard), on cashew, Anacardium occidentale, one of its host plants in Trinidad, West Indies, is considered in relation to the annual period of maximum population increase on this host and to the choice of feeding sites on individual leaves. On trees observed for three years, populations regularly increased during the dry season, from a low level in December and January to a peak in April or May, and then rapidly declined during the wet season. Even when thrips were most abundant, some trees were free from attack, and this could not be attributed to protective morphological features, to specific repellent substances in the leaf, or to chance. S. rubrocinctus was found to feed on leaves that were subjected to water-stress and to breed only on debilitated trees: the evidence suggested that the adequacy of its supply of nutrients depends on the induction of suitable metabolic conditions within the leaf by water-stress.Both nymphs and adults normally feed on the lower, stomata-bearing surface of the leaf, but in a very humid atmosphere only a weak preference is shown for this surface and if, under natural conditions, it is exposed to insolation by inversion of the leaf, the insects migrate to the other surface. Since the thrips were shown to be indifferent to bodily posture, the observation suggests that their behaviour is governed primarily by avoidance of exposure to undue heat or dryness and only secondarily by the attractiveness of the stomata-bearing surface.Leaves of cashew tend not to become infested while still immature, and become most heavily infested, if at all, soon after they have hardened. Breeding does not occur on senescent leaves. The positions of feeding thrips are almost random on leaves under abnormal water-stress, but otherwise conform to certain patterns that mainly develop in fixed sequence. On reversal of an undetached leaf and consequent transfer of thrips from one surface to the other, there is no appreciable change in their distribution pattern or the apparent acceptability of the substrate. Changes of pattern were readily induced by injury to the plant during a period of water-stress and less easily, or not at all, when water-stress was low. Injury of areas of the leaf by heat was followed by their colonisation by thrips, and partial severance of branches by increased attack on their leaves.Leaves detached from uninfested trees invariably became acceptable for feeding within four hours. During this period, leaf water-content declined and the ratios of soluble-carbohydrate content and α-amino acids to fresh-leaf weight fell slightly and rose considerably, respectively. In the field, the latter ratio was invariably higher for infested than for uninfested leaf tissue, even on portions of the same leaf. If the nutrient value of leaf tissue is determined by the rate at which α-amino acids are extractable through a stylet puncture, the observed change in acceptability for feeding following plucking may be accounted for by the increase in α-amino-acid concentration. Feeding that is restricted on any one tree to the margins of local leaf injuries during prolonged high water-stress and totally absent when stress is low can be correlated with an α-amino-acid content in the living marginal tissue that is high or low, respectively. The ability of thrips to establish themselves and breed on leaves of a particular tree in the dry season and their failure to do so on leaves of the same tree in the wet season conforms with the greater or less amino-acid concentration occurring in the leaf at these respective times.

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