Effect of asparagine,cysteine, citrulline,and glutamine on in vitro rooting and biochemical constituents in cherry rootstocks

Effects of four amino acids, L-asparagine, L-cysteine, L-citrulline, and L-glutamine in different concentrations (0, 0.5, 1, and 2 mg dm^-3) combined with 2 mg dm^-3 indole-3-butyric acid, on in vitro rooting and biochemical constituents of cherry rootstocks CAB-6P (Prunus cerasus L.) and Gisela 6 (P. canescens × P. cerasus) were investigated. In CAB-6P, root number and root fresh mass (FM) were maximum at 0.5 mg dm^-3 cysteine. All amino acids reduced root length in CAB-6P and root number as well as root FM in Gisela 6. In Gisela 6, 0.5 mg dm^-3 asparagine or 2 mg dm^-3 glutamine reduced root length. In CAB-6P, 100 % rooting was achieved in the control and with 1 and 2 mg dm^-3 cysteine or 1 mg dm^?3 citrulline. In Gisela 6, the rooting percentage was maximum (76.92 %) with 0.5 mg dm^?3 asparagine. Callus FM in CAB-6P was the greatest at 1 mg dm^?3 and in Gisela 6 at 2 mg dm^?3 citrulline. Callusing was 100 % in the majority of treatments for CAB-6P and 92.31 % for Gisela 6 with 0.5 or 2 mg dm^?3 citrulline. Cysteine, citrulline, and glutamine diminished chlorophyll content in Gisela 6 whereas in CAB-6P all four amino acids hardly affected it. Carotenoid and porphyrin content in CAB-6P was decreased due to asparagine (0.5 or 1 mg dm^?3). Porphyrin content in CAB-6P was also reduced by adding 0.5 or 1 mg dm^?3 cysteine or 2 mg dm^?3 citrulline. In Gisela 6, all amino acids decreased carotenoid and porphyrin content. In CAB-6P, all treatments except 0.5 mg dm^?3 glutamine or 2 mg dm^?3 asparagine increased leaf sucrose content. In roots, both sucrose and proline content were increased only at 1 mg dm^?3 cysteine whereas in leaves only 0.5 mg dm^?3 asparagine caused a 3-fold increase in proline content. A decrease in root proline in CAB-6P was observed due to asparagine, citrulline, or glutamine. In Gisela 6, decreased leaf sucrose and proline content was recorded at 2 mg dm^?3 cysteine. All amino acids did not alter root sugar content remarkably whereas root proline content was raised by adding 0.5 mg dm^?3 glutamine or 1 mg dm^?3 cysteine.     

Influence of amino acids,mammalian serum,and osmotic pressure on the proliferation of Drosophila cell lines

In the D22 medium of ECHALIER and OHANESSIAN for the culture of Drosophila cell lines lactalbumin hydrolysate could be replaced by a synthetic amino acids mixture. In spite of the presence of yeast extract and fetal calf serum the omission of any one of arginine, asparagine, cysteine, histidine, methionine, proline, serine, or threonine prevented cell proliferation. Of these eight amino acids cysteine had to be added in concentrations higher than 0.1 mM. Without much effect on cell proliferation foetal calf serum could be reduced from 10% to 2% or be replaced by 1% horse serum or 1% porcine serum. Cells could grow in media of osmolarities from 225 mOsm up to 400 mOsm depending on the osmotic agent used. Chloride concentrations up to 80 mM were compatible with proliferation as was a wide range of sodium/potassium ratios.     

Yeast methionine aminopeptidase I. Alteration of substrate specificity by site-directed mutagenesis

In eukaryotes, two isozymes (I and II) of methionine aminopeptidase (MetAP) catalyze the removal of the initiator methionine if the penultimate residue has a small radius of gyration (glycine, alanine, serine, threonine, proline, valine, and cysteine). Using site-directed mutagenesis, recombinant yeast MetAP I derivatives that are able to cleave N-terminal methionine from substrates that have larger penultimate residues have been expressed. A Met to Ala change at 329 (Met206 in Escherichia coli enzyme) produces an average catalytic efficiency 1.5-fold higher than the native enzyme on normal substrates and cleaves substrates containing penultimate asparagine, glutamine, isoleucine, leucine, methionine, and phenylalanine. Interestingly, the native enzyme also has significant activity with the asparagine peptide not previously identified as a substrate. Mutation of Gln356 (Gln233 in E. coli MetAP) to alanine results in a catalytic efficiency about one-third that of native with normal substrates but which can cleave methionine from substrates with penultimate histidine, asparagine, glutamine, leucine, methionine, phenylalanine, and tryptophan. Mutation of Ser195 to alanine had no effect on substrate specificity. None of the altered enzymes produced cleaved substrates with a fully charged residue (lysine, arginine, aspartic acid, or glutamic acid) or tyrosine in the penultimate position.     

Speculations on the evolution of the genetic code II

An evolutionary scheme is postulated in which a primitive code, involving only guanine and cytosine, would code for glycine (GG), alanine (GC), arginine (CG) and proline (CC). From each of these amino acids and their codons, there evolves a family of related amino acids as the code expands. The four families are: (1)alanine valine, leucine, isoleucine, phenylalanine, tyrosine, methionine and tryptophane; (2)proline, threonine and serine; (3)arginine, lysine, and histidine; (4)glycine, serine, cysteine, glutamic acid, glutamine, aspartic acid and asparagine. Except for the glycine relation to glutamic acid and aspartic acid, all amino acids are related by chemical similarities in their side chains. Glycine not having a side chain would permit a more complex set of substitutions.     

Amino Acids as Nitrogen Sources for the Growth of Euglena gracilis and Astasia longa

SYNOPSIS. Euglena gracilis (bacillaris variety, strain SM-L1, streptomycin-bleached) used the following amino adds (10⁻³ M) as sole nitrogen source for growth on a defined medium: glycine, alanine, valine, leucine, isoleucine, serine, threonine, and glutamic acid. Aspartic acid was used at 10⁻² M. Glutamine and asparagine were used at 10⁻³ M and were better N sources than their parent dicarboxylic amino acids. Not used as sole N source for growth were phenylalanine, tyrosine, tryptophan, cysteine, cystine, methionine, proline, hydroxyproline, histidine, arginine, lysine, and taurine. Astasia longa (Jahn strain) was more restricted than Euglena and used only asparagine and glutamine as N sources for growth.     

Chemotaxis toward amino acids in Escherichia coli

Escherichia coli cells are shown to be attracted to the l-amino acids alanine, asparagine, aspartate, cysteine, glutamate, glycine, methionine, serine, and threonine, but not to arginine, cystine, glutamine, histidine, isoleucine, leucine, lysine, phenylalanine, tryptophan, tyrosine, or valine. Bacteria grown in a proline-containing medium were, in addition, attracted to proline. Chemotaxis toward amino acids is shown to be mediated by at least two detection systems, the aspartate and serine chemoreceptors. The aspartate chemoreceptor was nonfunctional in the aspartate taxis mutant, which showed virtually no chemotaxis toward aspartate, glutamate, or methionine, and reduced taxis toward alanine, asparagine, cysteine, glycine, and serine. The serine chemoreceptor was nonfunctional in the serine taxis mutant, which was defective in taxis toward alanine, asparagine, cysteine, glycine, and serine, and which showed no chemotaxis toward threonine. Additional data concerning the specificities of the amino acid chemoreceptors with regard to amino acid analogues are also presented. Finally, two essentially nonoxidizable amino acid analogues, alpha-aminoisobutyrate and alpha-methylaspartate, are shown to be attractants for E. coli, demonstrating that extensive metabolism of attractants is not required for amino acid taxis.     

Synthesis,binding ability,and cell cytotoxicity of fluorescent probes for l‐arginine detection based on naphthalene derivatives: Experiment and theory

Inspired by biological related parts, Schiff base derivatives and functional groups of chemical modification can provide efficient detection method of amino acids. Therefore, we have designed and prepared 4 compounds based on Schiff base derivatives involving ─NO₂, ─OH, and naphthyl group. Results indicated that compound 4 containing 2 nitro groups showed strong sensitivity and high selectivity for arginine (Arg) among normal 18 kinds of standard amino acids (alanine, valine, leucine, isoleucine, methionine, aspartic acid, glutamic acid, arginine, glycine, serine, asparagine, phenylalanine, histidine, tryptophan, proline, lysine, glutamine, and cysteine). Theoretical investigation also approved the strong binding ability of compound 4 for Arg. In addition, compound 4 displayed high combining ability of Arg and low cytotoxicity of MCF‐7 cell in the 0 to 150 μg mL^?1 of concentration range; it can be used for Arg in vivo detection of fluorescent probe.     

Survival, fecundity and fertility of Bactrocera oleae, as affected by amino acid analogues

The effect of twenty five amino acid analogues at various concentrations upon the adult olive fruit fly Bactrocera oleae Gmelin (Diptera: Tephritidae), was tested. Insect survival was significantly shortened by the following amino acid analogues: (in parentheses are indicated the antagonized amino acids) D-cycloserine (alanine), L-glutamic acid--hydrazide (glutamine), DL-allyl-glycine (cysteine), L-canavanine (arginine), L-methionine-DL-sulfoximine (methionine) and 3,4-dehydro-DL-proline (proline). Fecundity was significantly reduced by the same analogues plus aminoethanesulfonic acid (glycine), taurine (alanine), L-norvaline (leucine), a-methyl-DL-serine (serine), DL-hydroxyglutamic acid (glutamic acid), (S)-2-(aminoethyl)-L-cysteine (lysine), a-methyl-DL-methionine (methionine) and a-methyl-DL-histidine (histidine). All the above amino acid analogues also depressed egg-hatching with the exception of taurine, DL-hydroxyglutamic acid, DL-allyl glycine, a-methyl-DL-methionine and a-methyl-DL-histidine. Finally, y-glutamyl-p-nitroanilide (glutamic acid), crotyl-glycine (methionine), DL-7-azatryptophan and 5-methyl-DL-tryptophan (tryptophan), DL-1,2,4 triazole-3-alanine (histidine) and DL-pipecolic acid (proline) did not affect any of the parameters tested.     

Relationship between Auxin and Amino Acid Metabolism of Tobacco Protoplast-Derived Cells

Single amino acids were found to be highly toxic to protoplast-derived cells of tobacco (Nicotiana tabacum cv Xanthi) cultured at low density in a culture medium containing a low naphthaleneacetic acid concentration (0.05 micromolar). The cytotoxicities of alanine, aspartic acid, asparagine, glutamic acid, glutamine, glycine, lysine, proline, and valine were reduced when the naphthaleneacetic acid concentration of the culture medium was increased to 1 micromolar. This selective modification of amino acid toxicity by naphthaleneacetic acid could not be correlated with modifications of uptake rates or incorporation of these amino acids into protein or amino acid-auxin conjugates. A mutant clone resistant to high naphthaleneacetic acid concentrations and affected in root morphogenesis did not display, at the cellular level, the naphthaleneacetic acidmediated modification of amino acid cytotoxicity.     

Free Amino-acids in the Endosperm of the Developing Coconut (Cocos nucifera)

The free amino-acids in the sap flowing from the incised inflorescenceof the coconut palm (Cocos nucifera) and in the liquid and solidendosperm of the coconut at various stages of development (4–12months from the time of opening of the spathe) have been studiedby paper and ion-exchange chromatography. The chief amino-acids in the sap were in decreasing order ofmagnitude: glutamic acid, aspartic acid, glutamine, serine,and asparagine. Smaller amounts of threonine, alanine, -aminobutyricacid, proline, valine, arginine, and tryptophan were found,along with traces of tyrosine, ß-alanine, lysine,histidine, leucine, isoleucine, and methionine. The chief amino-acids in the liquid endosperm of the nut until6 months of age were alanine, glutamic acid, serine, valine,and proline with smaller amounts of asparagine, aspartic acid,glycine, threonine, leucine, isoleucine, and glutamine. Thealanine, glutamic acid, proline, and -aminobutyric acid contentsof the liquid endosperm increased greatly as the solid endospermwas laid down, ultimately forming about 75 per cent. of thetotal free amino-acids. Nineteen amino-acids were detected atthe 8–10-month stage. -Aminobutyric acid appears in the liquid endosperm soon afterthe solid endosperm commences to form, and increases strikinglythereafter. It was also found in the free amino-acids of thesolid endosperm at all stages of development. This amino-acidwas not found in the acid hydrolysate of coconut globulin. The free amino-acids in the solid endosperm were found to reflectqualitatively the free amino-acid composition of the correspondingliquid endosperm. In addition, ß-alanine, -aminobutyricacid, phenylalanine, and tryptophan were present in small amounts.Alanine, serine, glutamic acid, and -aminobutyric acid, increasedwith age of the nut while the others increased up to 6 monthsand then decreased, only traces being found at maturity exceptin the case of aspartic acid, proline, and threonine. Twenty-oneamino-acids were detected in the free amino-acids of the solidendosperm. The source of the free amino-acids in the liquid endosperm andthe possible use of these amino-acids for protein synthesisin the coconut are briefly discussed.     

Electroencephalogram recordings from the olfactory bulb of juvenile (0 year) Atlantic cod in response to amino acids

Olfactory sensitivity of juvenile (0 year) Atlantic cod Gadus morhua to 20 L‐amino acids was studied by recording electroencephalograms (EEG) from the olfactory bulb. Leucine, methionine, asparagine, glutamine, alanine and threonine were highly stimulatory; proline, phenylalanine, aspartic acid and tryptophan were the least stimulatory. Threshold concentrations determined for four amino acids were 10⁻⁸ M for alanine, 10⁻⁷ M for arginine and leucine and 10⁻⁶ M for glutamic acid.     

Free energies of amino acid adsorption on silica in neutral aqueous medium as estimated from high-performance liquid-chromatographic retention data

Summary Equilibrium constants (K) and free energies (–G) of amino acid adsorption on silica in a neutral aqueous medium were calculated from the retention values measured by means of high-performance liquid chromatography on a silica gel column. For most amino acids (with the exception of proline) –G values were negative andK < 1, thus showing very low adsorption. Influence of the structure of the-substituent on adsorbability is analyzed. A linear dependence of –G on the number of aliphatic carbon atoms was shown for the series: glycine-alanine-valine-leucine-isoleucine.Abbreviations Gly glycine - Ala alanine - Pro proline - Val valine - Ile isoleucine - Leu leucine - Ser serine - Thr threonine - Cys cysteine - Asn asparagine - Gln glutamine - Asp aspartic acid - Glu glutamic acid - Met methionine - His histidine - Phe phenylalanine - Tyr tyrosine - DOPA 3,4-dioxyphenylalanine - Trp tryptophan     

Amino acid utilization by L-M strain mouse cells in a chemically defined medium

Summary The amino acid requirements of strain L-M mouse cells grown in a chemically defined medium (2×Eagle) containing only the 13 essential amino acids (EAA) were investigated. Medium and acid hydrolysate samples were analyzed for amino acid content by the method of ion exchange chromatography. The extent of utilization of the EAA differed;e.g. after 120 hr of cell growth without medium change, glutamine was exhausted from the medium; methionine, leucine, isoleucine, cystine, arginine, and valine were depleted 60 to 80%; other EAA were used to lesser extents. Although the EAA were used in excess of their requirements for protein synthesis, a correlation could generally be made between utilization and protein amino acid composition. Glutamine appeared to be, a growth-limiting factor. Use of U-¹⁴C-labeled glutamine indicated that over one-half of the metabolized glutamine was converted to carbon dioxide, 17% to cell material, and 15% was extracted from the amino acid pools. Nonessential amino acids (NEAA), viz. alanine, aspartic acid, glutamic acid, glycine, proline, and serine, were released into the medium during growth, and some were reutilized. Exogenous provision of these did not improve cell growth. In contrast to the other NEAA, only serine showed net utilization when provided exogenously. When glutamic acid largely replaced the glutamine in the medium, it exerted a sparing effect on the glutamine requirement for protein synthesis. Suggestions are given for the improvement of Eagle medium for cell growth. Supported by Research Grants CA 03720 and CA 11802 from the National Institutes of Health. Predoctoral, fellow supported, by Grant F01-GM-42156-02 from the National Institutes of Health.     

凤眼莲根分泌物氨基酸组分对根际肠杆菌属F2细菌的趋化作用

凤眼莲(Eichhornia crassipes)的根分泌物中含有Met等多种氨基酸,其中Met、GABA、Gly、Ala、Asp、Ser、Val和Leu(10^-7～10^-2mol·L^-1)均对凤眼莲的根际肠杆菌属F₂(Enterobacter sp.F₂)细菌有强烈的正趋化作用;Glu、Thr和His(10^-7～10^-3mol·L^-1)也对该菌有一定的正趋化作用;而Lys、Cys、Arg、Tyr、Pro、Asn、Gln、Ile、Phe和Typ则对该菌表现出一定的负趋化作用.对细菌的正趋化作用存在一个趋化物的最适浓度范围.具有正趋化作用的氨基酸在凤眼莲根际的浓度都较高,而具有负趋化作用的浓度则较低,这正是凤眼莲与该根际细菌结合为根际微生态系统的原因之一.     

Nutritional requirements of anaerobic coryneforms.

The nutritional requirements of three species of anaerobic coryneforms and their serotypes (Propionibacterium acnes types I and II, P. avidum types I and II, and P. granulosum) were determined. Strains of P. avidum would consistently grow to a transmittance of 1 to 3% at 560 nm in a basal salts medium supplemented with glucose, pantothenate, biotin, thiamine, and 12 amino acids (alanine, arginine, cysteine, glutamine, glycine, histidine, isoleucine, methionine, phenylalanine, serine, tyrosine, and tryptophan). Strains of P. acnes and P. granulosum, however, failed to grow in this medium unless six additional amino acids were present (asparagine, leucine, lysine, proline, threonine, and valine). All three species grew equally well whether the 18 amino acids were supplied in the form of a casein hydrolysate supplemented with tryptophan or were added separately. Nicotinamide enhanced growth of P. acnes but had no effect on growth of P. avidum and P. granulosum. Other nutrients which were not absolute requirements, but which significantly improved growth of these species, included the purines guanine and/or adenine, Tween 80, which served as a source of oleic acid, sodium L-lactate, alpha-ketoglutarate, and pyruvate. Strains (86) comprising all five groups grew well in the defined medium, except four strains of P. acnes type II (29 tested), which failed to grow unless heme and vitamin K were added to the medium. One strain of P. granulosum (22 tested) failed to grow in any defined medium, suggesting an additional growth factor requirement.     

Use of amino acids by Plasmodium relictum oocysts in vitro.

A comparison was made of the in vitro growth of the gut of Culex tarsalis in Grace's insect culture medium, supplemented with fetal bovine serum in the presence of dividing cells of Antheraea eucalypti, with a similar preparation of a gut infected with oocysts of the avian parasite, Plasmodium relictum. In the latter case, after 16 hr, significant decreases occurred in the concentration of arginine, asparagine, and glutamine combined, glutamic acid, glycine, histidine, lysine, proline, and serine. Lower and less marked decreased concentrations of alanine, β-alanine, cystine, isoleucine, leucine, methionine, ornithine, phenylalanine, threonine, tryptophane, tyrosine, and valine also took place. This indicated utilization of certain amino acids by the developing oocysts of P. relictum in the presence of metabolizing insect cells.     

Isolation and properties of two allelic chymotrypsin inhibitors from the hemolymph of the silkworm,Bombyx mori

A chymotrypsin inhibitor, CI-1, and its co-dominant allelic counterpart CI-2, detectable in certain strains of Bombyx mori each as an electrophoretic band close to the origin, were purified from the larval hemolymph by using ion-exchange and affinity chromatography. CIs 1 and 2 were monomeric neutral proteins with a pI of 7.12 and 7.00 and an M_r of about 10,400 and 7900, respectively. Amino acid analysis showed that these inhibitors were rich in aspartic acid (or asparagine), glutamic acid (or glutamine) and lysine, but poor, or lacking, in valine, methionine, histidine and arginine. In the amino-terminal sequence, 14 out of 20 amino acid residues analyzed were common between CIs 1 and 2.     

Utilization and requirements of amino acids by a cell line derived from the butterfly Papilio xuthus

The media, in which a butterfly cell line (Px 58), derived from pharate adult ovaries of Papilio xuthus cultured for 8 days, were analysed to examine the changes in free amino acids in the medium during cultivation. Beta-alanine, arginine, glycine, histidine, lysine, phenylalanine, proline, serine, and tryptophan did not change markedly. Asparagine, aspartic acid, cystine, glutamine, isoleucine, leucine, methionine, threonine, tyrosine, and valine decreased to some extent with culturing. Alpha-alanine increased markedly, and glutamic acid did so to a lesser extent. Requirements of amino acids by the cell line were examined by deleting amino acids one at a time. Deletion of alpha-alanine, beta-alanine, asparagine, glutamic acid, glycine, and phenylalanine did not cause deterioration of the cell. These amino acids were thought to be non-essential or required only a little. Deletion of other amino acids impaired the cell growth severely. These amino acids would appear to be essential for growth of the Px 58 cell line.     

Amino acid utilization by L-M strain mouse cells in a chemically defined medium

Summary The amino acid requirements of strain L-M mouse cells grown in a chemically defined medium (2×Eagle) containing only the 13 essential amino acids (EAA) were investigated. Medium and acid hydrolysate samples were analyzed for amino acid content by the method of ion exchange chromatography. The extent of utilization of the EAA differed;e.g. after 120 hr of cell growth without medium change, glutamine was exhausted from the medium; methionine, leucine, isoleucine, cystine, arginine, and valine were depleted 60 to 80%; other EAA were used to lesser extents. Although the EAA were used in excess of their requirements for protein synthesis, a correlation could generally be made between utilization and protein amino acid composition. Glutamine appeared to be a growth-limiting factor. Use of U-¹⁴C-labeled glutamine indicated that over one-half of the metabolized glutamine was converted to carbon dioxide, 17% to cell material, and 15% was extracted from the amino acid pools. Nonessential amino acids (NEAA), viz. alanine, aspartic acid, glutamic acid, glycine, proline, and serine, were released into the medium during growth, and some were reutilized. Exogenous provision of these did not improve cell growth. In contrast to the other NEAA, only serine showed net utilization when provided exogenously. When glutamic acid largely replaced the glutamine in the medium, it exerted a sparing effect on the glutamine requirement for protein synthesis. Suggestions are given for the improvement of Eagle medium for cell growth. Supported by Research Grants CA 03720 and CA 11802 from the National Institutes of Health. Predoctoral fellow supported by Grant F01-GM-42156-02 from the National Institutes of Health. Present address: Department of Community Medicine. Basic Science Building, University of California, San Diego, La Jolla, Calif. 92037.