The co-occurrence of two diastereoisomers of 2,3-diaminobutanoic acid in root nodule hydrolysates of Lotus tenuis

The non-protein amino acid 2, 3-diaminobutanoic acid has been identified in the root nodules of Lotus tenuis inoculated with Rhizobium strain NZP2213. The co-occurrence of this compound in two diastereoisomeric forms was established by comparative GC retention time measurements on a Chirasil—Val capillary column.     

l-2-Oxalylamino-3-aminopropionic acid,an isomer of Lathyrus sativus neurotoxin

The first chemical synthesis of l-2-oxalylamino-3-aminopropionic acid, an isomer of the Lathyrus sativus neurotoxin, is described. Studies on its biological properties are reported. Experiments with l-3-[¹⁴C-oxalyl]amino-2- aminopropionic acid show that the amount of 2-oxalylamino isomer detectable in seed extracts can be accounted for by rearrangement which occurs during isolation.     

Erythro-γ-hydroxyhomo-L-arginine: An amino acid from seed of Lonchocarpus costaricensis, and its preferential interaction with borate

A new non-protein amino acid, erythro-γ-hydroxyhomo-L-arginine has been isolated from seed of Lonchocarpus costaricensis by exploiting its property of interacting with borate ions. For structural comparisons, threo-γ-hydroxyhomo-L-arginine was isolated from seed of Lathyrus tingitanus and erythro-γ-hydroxyarginine from Vicia unijuga by novel procedures. The reasons for the interaction of borate with the erythro- but not the threo-forms of these amino acids are discussed.     

2-amino-4-acetylaminobutyric acid, 2,4-diaminobutyric acid and 2-amino-6N-oxalylureidopropionic acid (oxalylalbizziine) in seeds of acacia angustissima

A new amino acid previously detected in 17 species of Acacia has been isolated from seeds of Acacia angustissima and identified as oxalylalbizziine. These seeds also contain more than 6% dry weight of 2-amino-4-acetylaminobutyric acid, which has not been reported previously in a legume, and lower concentrations of 2,4-diaminobutyric acid.     

Sulphate ester of trans-4-hydroxypipecolic acid in seeds of Peltophorum

An acidic compound isolated from seed of the legume Peltophorum africanum has been characterised on the basis of FAB-MS, EIMS, ¹³C and ¹H NMR as trans-4-hydroxypipecolic acid-4-sulphate. This is the first naturally occurring sulphate ester of a non-protein amino acid to be described. The possible systematic significance of the distribution of the ester within Peltophorum and related genera is considered.     

2,4-Dichlorophenoxyacetic acid and the de novo synthesis of invertase in chicory root tissue

Using a dual radioactive labelling technique, the large 2,4-D induced increase in invertase activity in root tissue of chicory (Cichorium intybus) could not be attributed to de novo protein synthesis. The highly active enzyme could have arisen by modification of an inactive enzyme precursor.     

Stereochemistry of 2-aminopimelic acid and related amino acids in three species of asplenium

We previously reported two free D-amino acids, D-2-aminopimelic acid (D-APA) and trans-3,4-dehydro-D-2-aminopimelic acid (D-Δ-APA), from Asplenium unilaterale. In the present work we isolated 4-hydroxy-2-aminopimelic acid (OH-APA) from the same plant and determined it to be the α-L-form. We also investigated the configurations of these amino acids isolated from A. prolongatum and A. wilfordii which are morphologically distinct from A. unilaterale. In A. prolongatum, APA was the D- and OH-APA was the L-isomer. In contrast, APA from A. wilfordii was partially racemized and the degree of racemization was significantly different in plant material collected in July and November, L:D = 3:2 and 3:7, respectively. In A. wilfordii OH-APA was almost pure L- and Δ-APA was mostly the D-isomer.     

The amino acid sequence of cytochrome c from niger-seed, Guizotia abyssinica

The amino acid sequence of cytochrome c from niger-seed has been determined by sequence analysis of chymotryptic and tryptic peptides using the dansyl-phenylisothiocyanate method and by qualitative analysis of peptide composition by the dansyl method. Although the spectral ratios indicated the protein was not completely pure, no indication of impurity was found during the sequence analysis and no peptides in addition to those given here were obtained. In certain cases the alignment of peptides was by homology with other cytochromes c. Four residues in the proposed sequence, alanine-1, cysteine-25, histidine-26 and lysine-61 were identified only from peptide compositions. The amino-terminus of the protein is acetylated. The sequence contains two residues of ϵ-N-trimethyllysine.     

Clithioneine,an amino acid betaine from clitocybe acromelalga

A new amino acid betaine, clithioneine, was isolated from a poisonous mushroom Clitocybe acromelalga, and its structure was established on the basis of spectral analyses and chemical degradation studies.     

A populational survey of amino acids in Prosopis species from North and South America

Leaf extracts of 540 plants representing 24 species of the genus Prosopis from North and South America were analyzed by 2-D PC and high voltage electrophoresis for their protein and non-protein amino acids. In addition to the presence of the usual protein amino acids, most of the species examined contained high concentrations of the non-protein amino acids, pipecolic acid, 4-hydroxypipecolic acid and proline.     

2,4-Trans-4,5-trans-4,5-dihydroxypipecolic acid and cis-5-hydroxypipecolic acid from leaves of Calliandra angustifolia and sap of C. Confusa

2,4-Trans-4,5-trans-4,5-dihydroxypipecolic acid and cis-5-hydroxypipecolic acid have been isolated from the leaves of Calliandra angustifolia and the sap of C. confusa. Distribution of these and other non-protein amino acids is discussed.     

DOPA synthesis in non-producer cultures of Mucuna deeringiana

Cell cultures of Mucuna deeringiana on various media fail to accumulate DOPA or stizolobic acid. Radiotracer studies prove that both compounds are being synthesized in the cells; however, the apparent lack of production is due to metabolic emphasis on catabolism instead of storage.     

The amino acid sequence of plastocyanin from Cucumis sativus

The amino acid sequence of plastocyanin from cucumber (Cucumis sativus) has been determined. Analysis was by the dansyl—phenylisothiocyanate meth     

A novel abscisic acid metabolite from seeds of Robinia pseudacacia

Abscisic acid and its novel metabolise, which was a conjugated form of hydroxyabscisic acid (Metabolite C), were isolated from seeds of Robinia pseudacacia L. The structure of the conjugate was shown to be (+)-3-methyl-5 - [1(S),6(R) - 2,6 - dimethyl - 1 - hydroxy - 6 - (3 - hydroxy - 3 - methyl - 4 - carboxybutanoyloxymethyl) - 4 - oxo-cyclohex-2-enyl]-2-Z-4-E-pentadienoic acid and tentatively named β-hydroxy-β-methylglutarylhydroxyabscisic acid.     

The amino acid sequences of plastocyanin from Mercurialis perennis and Capsella bursa-pastoris

The amino acid sequences of the plastocyanins from Mercurialis perennis and Capsella bursa-pastoris have been determined. The amides at positions 64 and 68 in the Mercurialis sequence were positioned by ‘homology’ Both proteins are single polypeptide chains of 99 residues and are closely related to other higher plant plastocyanins.     

Effect of 2,4-dichlorophenoxyacetic acid treatment on the soluble and cell wall bound protein in Cichorium intybus root tissue

Measurements have been made of protein and activities of enzymes bound to the cell wall of chicory root tissue. It has been shown that promotion of cell enlargement brought about by treatment with the highly active growth regulator 2,4-dichlorophenoxyacetic acid (2,4-D) does not arise from bound enzyme released from the wall. Experiments with inhibitors of protein synthesis suggest that the enhanced invertase and hydrolase activity found in soluble protein extracts after 2,4-D treatment arises from the synthesis of small amounts of protein.     

Acidic amino acids in Reseda luteola

3-(3-Carboxyphenyl)alanine, (3-carboxyphenyl)glycine, 3-(3-carboxy-4-hydroxyphenyl)alanine and (3-carboxy-4-hydroxyphenyl)glycine occur in all parts of Reseda luteola. The concentrations of the two diastereoisomers of 2(S)-4-hydroxy-4-methylglutamic acid undergo seasonal variation, the highest concentrations occurring in the first part of the summer. Highest concentrations are found in the inflorescences. The two diastereoisomers of 2(S)-4-hydroxy-2-aminopimelic acid occur in appreciable amounts in all parts of the plant. They are easily transformed into two structurally different lactones, one of which is very unstable. The structures of these amino acids have been confirmed by synthesis. Green parts of R. luteola also contain substantial quantities of γ-glutamylglutamic acid and glutathione.     

Saccharopine and 2-aminoadipic acid in Reseda odorata

2(S),2′(S)-N⁶-(2′-Glutaryl)lysine (l-saccharopine) and 2(S)-2-aminoadipic acid have been isolated from Reseda odorata. When traditional isolation procedures are used l-pyrosaccharopine (5(S),5′(S)-N-(5′-amino-5′-carboxy-pentyl)-2-pyrrolidone-5-carboxylic acid) is formed from l-saccharopine by lactamisation. The degree of lactamisation during various isolation steps has been studied, The amino acids were identified by IR and PMR spectroscopy and the configurations established by enzymic and polarimetric analyses. The contents of saccharopine and 2-amino-adipic acid have been determined relative to the total nitrogen content at various stages in the growth cycle of R. odorata.     

Amino acid substrate specificity of asparaginyl-,aspartyl- and glutaminyl-tRNA synthetase isolated from higher plants

AspNH₂-, Asp- and GluNH₂-tRNA synthetases were purified from Phaseolus aureus; their optimum assay conditions, substrate specificities and salt sensitivities were investigated. AspNH₂-tRNA synthetase from β-cyanoalanine-producing (Vicia sativa), and non-producing (P. aureus and V. faba) species was able to utilize the analogue as a substrate irrespective of the source of the enzyme. Asp-tRNA synthetase from P. aureus was able to utilize α-aminomalonate and threo-β-hydroxy Asp as a substrate. The transfer of ¹⁴C-GluNH₂ to tRNA, catalyzed by GluNH₂-tRNA synthetase, was only inhibited by high concentrations of those analogues tested; albizziine was the most efficient, but no difference could be demonstrated between the substrate specificities of the enzyme isolated from an albizziine-producer (A. julibrissin and a non-producer (P. aureus) species.