scholarly journals Nitrate Promotes Capsaicin Accumulation inCapsicum chinenseImmobilized Placentas

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Jeanny G. Aldana-Iuit ◽  
Enrique Sauri-Duch ◽  
María de Lourdes Miranda-Ham ◽  
Lizbeth A. Castro-Concha ◽  
Luis F. Cuevas-Glory ◽  
...  
Keyword(s):  
Amino Acids ◽  
Structural Damage ◽  
Inorganic Nitrogen ◽  
Placental Tissue ◽  
Nitrogen Sources ◽  
Nitrate Content ◽  
Tissue Sections ◽  
Scanning Electron Microcopy ◽  
Branched Amino Acids

In chili pepper’s pods, placental tissue is responsible for the synthesis of capsaicinoids (CAPs), the compounds behind their typical hot flavor or pungency, which are synthesized from phenylalanine and branched amino acids. Placental tissue sections from Habanero peppers (Capsicum chinenseJacq.) were immobilized in a calcium alginate matrix and culturedin vitro, either continuously for 28 days or during two 14-day subculture periods. Immobilized placental tissue remained viable and metabolically active for up to 21 days, indicating its ability to interact with media components. CAPs contents abruptly decreased during the first 7 days in culture, probably due to structural damage to the placenta as revealed by scanning electron microcopy. CAPs levels remained low throughout the entire culture period, even though a slight recovery was noted in subcultured placentas. However, doubling the medium’s nitrate content (from 40 to 80 mM) resulted in an important increment, reaching values similar to those of intact pod’s placentas. These data suggest that isolated pepper placentas culturedin vitroremain metabolically active and are capable of metabolizing inorganic nitrogen sources, first into amino acids and, then, channeling them to CAP synthesis.

THE IN VITRO RELEASE OF AMINO ACIDS BY RUMEN PAPILLAE

1980 ◽  
Vol 60 (2) ◽  
pp. 281-291 ◽  
Author(s):  
R. J. BOILA ◽  
L. P. MILLIGAN
Keyword(s):  
Amino Acids ◽  
Carbon Sources ◽  
In Vitro Release ◽  
Nitrogen Sources ◽  
Chromatographic Technique ◽  
Salts Of Organic Acids ◽  
Liquid Chromatographic ◽  
Vitro Release ◽  
Effective Source

Rumen papillae from cattle were incubated aerobically with combinations of NH4Cl, amino acids and salts of organic acids, the latter including propionate, pyruvate, α-ketoglutarate and glyoxylate. Amino acids in the incubation media were analyzed using a gas-liquid chromatographic technique entailing separation of the isobutyl-N(0)-heptafluorobutyryl esters: glutamine was recovered with glutamate, asparagine with aspartate, and citrulline with ornithine. Rumen papillae incubated with pyruvate or propionate released alanine, but with the latter substrate only glutamate was effective as a nitrogen source. Glycine and glutamate plus glutamine were released in the presence of glyoxylate and α-ketoglutarate, respectively. Serine and aspartate plus asparagine were not quantitatively major products released by rumen papillae. Glutamate was an effective source of nitrogen for the release of alanine and glycine with pyruvate and glyoxylate, respectively, as carbon sources. When rumen papillae were incubated with pyruvate or glyoxylate as the added carbon source, glutamine nitrogen disappeared and was not accounted for by the amino acids measured. With arginine as a substrate, there was a release of ornithine by rumen papillae indicating urea production. The tissues of rumen papillae appear to synthesize amino acids from expected carbon sources with ammonia or glutamate as nitrogen sources and to catabolize glutamine and arginine. The metabolism of amino acids by rumen papillae would contribute to the interchange of nitrogen between the rumen and the host.

scholarly journals An In Vitro TORC1 Kinase Assay That Recapitulates the Gtr-Independent Glutamine-Responsive TORC1 Activation Mechanism on Yeast Vacuoles

2017 ◽  
Vol 37 (14) ◽  
Author(s):  
Mirai Tanigawa ◽  
Tatsuya Maeda
Keyword(s):  
Amino Acids ◽  
Nitrogen Sources ◽  
Small Gtpases ◽  
Activation Mechanism ◽  
Kinase Assay ◽  
Content Type ◽  
Vacuolar Protein ◽  
Vacuolar Membranes ◽  
First Time

ABSTRACT Evolutionarily conserved target of rapamycin (TOR) complex 1 (TORC1) responds to nutrients, especially amino acids, to promote cell growth. In the yeast Saccharomyces cerevisiae, various nitrogen sources activate TORC1 with different efficiencies, although the mechanism remains elusive. Leucine, and perhaps other amino acids, was reported to activate TORC1 via the heterodimeric small GTPases Gtr1-Gtr2, the orthologues of the mammalian Rag GTPases. More recently, an alternative Gtr-independent TORC1 activation mechanism that may respond to glutamine was reported, although its molecular mechanism is not clear. In studying the nutrient-responsive TORC1 activation mechanism, the lack of an in vitro assay hinders associating particular nutrient compounds with the TORC1 activation status, whereas no in vitro assay that shows nutrient responsiveness has been reported. In this study, we have developed a new in vitro TORC1 kinase assay that reproduces, for the first time, the nutrient-responsive TORC1 activation. This in vitro TORC1 assay recapitulates the previously predicted Gtr-independent glutamine-responsive TORC1 activation mechanism. Using this system, we found that this mechanism specifically responds to l-glutamine, resides on the vacuolar membranes, and involves a previously uncharacterized Vps34-Vps15 phosphatidylinositol (PI) 3-kinase complex and the PI-3-phosphate [PI(3)P]-binding FYVE domain-containing vacuolar protein Pib2. Thus, this system was proved to be useful for dissecting the glutamine-responsive TORC1 activation mechanism.

Nitrogen nutrition and regulation of cephalosporin production in Streptomyces clavuligerus

1979 ◽  
Vol 25 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Yair Aharonowitz ◽  
Arnold L. Demain
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Nitrogen Nutrition ◽  
Antibiotic Production ◽  
Inorganic Nitrogen ◽  
Amino Nitrogen ◽  
Nitrogen Sources ◽  
Streptomyces Clavuligerus ◽  
Defined Medium ◽  
Repressive Effect

When used as sole nitrogen source, certain amino acids (e.g., proline, asparagine) supported both growth and sporulation by Streptomyces clavuligerus streaked onto solid defined medium. Ammonium supported growth but suppressed sporulation. Amino nitrogen was best for cephalosporin production in liquid defined medium, although urea was almost as useful. A comparison of amino acids showed asparagine and glutamine to be the best nitrogen sources and arginine to be almost as good. Ammonium salts supported a somewhat lower growth rate than asparagine, but antibiotic production was very poor on these inorganic nitrogen sources. Addition of ammonium to asparagine did not affect growth rate but increased mycelial mass; cephalosporin production was reduced by about 75%. Antibiotic production was more closely associated with growth in the absence of ammonium than in its presence, indicating a strong inhibitory and (or) repressive effect of NH4+ on antibiotic production. Ammonium exerted its negative effect when added at 24 h or earlier, i.e. before antibiotic formation began.

scholarly journals Effect of Nitrogen on in Vitro Propagation of Endangered Medicinal Plant: Swertia Chirayita Roxb. Ex Flaming

2021 ◽  
Vol 11 (2) ◽  
pp. 3513-3522
Keyword(s):  
Average Length ◽  
Inorganic Nitrogen ◽  
Nitrogen Sources ◽  
Multiple Shoots ◽  
Garden Soil ◽  
Equal Proportion ◽  
Ms Medium ◽  
Root Explants ◽  
Swertia Chirayita

The effect of nitrogen was investigated on the organogenesis of Swertia chirayita (Gentianaceae) to overcome the challenges related to its cultivation. The best callogenic response was observed on root explants inoculated onto MS medium supplemented with BAP (2.0 mg/l) along with 2,4-D (0.5 mg/l) after 35 days of culture. Subsequent transfer of callus for multiplication on the same media composition under complete darkness presents the best results in terms of callus multiplication. Callogenic cultures were subculture onto modified MS medium supplemented with inorganic nitrogen sources, i.e., NH4NO3 (14-56N/l), KNO3 (100-400N/l) with BAP (3.0 mg/l) were observed. Organogenic response (52%) was observed after 8-12 weeks of culturing. The maximum number of the shoot was recorded on MS medium with NH4NO3 (28 N/l), KNO3 (300N/l) with BAP (3.0 mg/l). Moreover, 90% of them were able to regrow when sub-cultured on the same media. Sixteen weeks old multiple shoots were subcultured on MS medium supplemented with different auxins. IAA was proved to be the best hormone rooting purpose. However, the best rooting response regarding the number of roots and an average length of roots was obtained at IAA (1.0 mg/l). Survival of 90% was achieved when rooted plantlets were successfully established in substrate containing sand, vermicompost, and garden soil in equal proportion for hardening and acclimatized.

scholarly journals A mixed nitrogen diet and compartmentalized utilization for Mycobacterium tuberculosis replicating in host cells: results of a systems-based analysis

2019 ◽  
Author(s):  
Khushboo Borah ◽  
Martin Beyss ◽  
Axel Theorell ◽  
Huihai Wu ◽  
Piyali Basu ◽  
...  
Keyword(s):  
Amino Acids ◽  
Mycobacterium Tuberculosis ◽  
Nitrogen Source ◽  
Nitrogen Metabolism ◽  
Nitrogen Sources ◽  
Spectral Ratio ◽  
Host Cells ◽  
Ratio Analysis ◽  
Nitrogen Donor

Nitrogen metabolism of Mycobacterium tuberculosis (Mtb) is crucial for the survival and virulence of this pathogen inside host macrophages but little is known about the nitrogen sources acquired from the host or their route of assimilation. Here we performed a systems-based analysis of nitrogen metabolism in intracellullar Mtb and developed 15N-Flux Spectral Ratio Analysis (FSRA) to probe the metabolic cross-talk between the host cell and Mtb. We demonstrate that intracellular Mtb acquires nitrogen from multiple amino acids in the macrophage including glutamate, glutamine, aspartate, alanine, glycine and valine, with glutamine being the predominant nitrogen donor. Each nitrogen source is uniquely assimilated into specific intracellular pools indicating compartmentalised metabolism. This was not observed for in vitro-grown Mtb indicating that there is a switch in nitrogen metabolism when the pathogen enters the intracellular environment. These results provide clues about the potential metabolic targets for development of innovative anti-tuberculosis therapies.

Interactions between nitrogen sources and xylose affecting growth, sporulation, and polyphenoloxidase activity in Bipolaris maydis race T

1981 ◽  
Vol 59 (11) ◽  
pp. 2102-2107 ◽  
Author(s):  
Robert C. Evans ◽  
Candace L. Black
Keyword(s):  
Amino Acids ◽  
Organic Nitrogen ◽  
Inorganic Nitrogen ◽  
Nitrogen Concentration ◽  
Relative Effectiveness ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
The Other ◽  
Growth Media ◽  
Bipolaris Maydis

The effect of 23 organic and 3 inorganic nitrogen sources on growth, sporulation, and polyphenoloxidase activity was measured in Bipolaris maydis race T incubated with or without a xylose supplement. Mycelial dry weight tends to be highest on acidic and other polar amino acids and least on nonpolar ones; organic nitrogen sources generally result in greater dry weight than inorganic ones. Changes in nitrogen concentration and pH of media influence growth and sporulation, but only pH alters the relative effectiveness of the nitrogen sources on these processes. The addition of xylose to the growth media has little effect on growth. However, in the presence of lysine, serine, asparagine, glycine, γ-alanine, alanine, and α-aminobutyrate, xylose causes an increase in sporulation and a concomitant decrease in polyphenoloxidase activity. There is no consistent pattern resulting from xylose addition in the presence of the other nitrogen sources.

scholarly journals Probing Direct Interactions between CodY and the oppD Promoter of Lactococcus lactis

2005 ◽  
Vol 187 (2) ◽  
pp. 512-521 ◽  
Author(s):  
Chris D. den Hengst ◽  
Peter Curley ◽  
Rasmus Larsen ◽  
Girbe Buist ◽  
Arjen Nauta ◽  
...  
Keyword(s):  
Amino Acids ◽  
Lactococcus Lactis ◽  
Nitrogen Availability ◽  
Nitrogen Sources ◽  
Dnase I ◽  
Site Directed Mutagenesis ◽  
Upstream Region ◽  
Binding Studies ◽  
Genes Encoding

ABSTRACT CodY of Lactococcus lactis MG1363 is a transcriptional regulator that represses the expression of several genes encoding proteins of the proteolytic system. These genes include pepN, pepC, opp-pepO1, and probably prtPM, pepX, and pepDA2, since the expression of the latter three genes relative to nitrogen availability is similar to that of the former. By means of in vitro DNA binding assays and DNase I footprinting techniques, we demonstrate that L. lactis CodY interacts directly with a region upstream of the promoter of its major target known so far, the opp system. Our results indicate that multiple molecules of CodY interact with this promoter and that the amount of bound CodY molecules is affected by the presence of branched-chain amino acids and not by GTP. Addition of these amino acids strongly affects the extent of the region protected by CodY in DNase I footprints. Random and site-directed mutagenesis of the upstream region of oppD yielded variants that were derepressed in a medium with an excess of nitrogen sources. Binding studies revealed the importance of specific bases in the promoter region required for recognition by CodY.

scholarly journals Nutritional characteristics and physiological studies on the growth and development of Phlebiopsis gigantea

2017 ◽  
Vol 8 ◽  
Author(s):  
Sushma Negi ◽  
Indu Bhushan Prasher ◽  
Rajeev Kumar
Keyword(s):  
Mycelial Growth ◽  
Inorganic Nitrogen ◽  
Nitrogen Compound ◽  
Nitrogen Sources ◽  
Physical Factors ◽  
Phlebiopsis Gigantea ◽  
Nutritional Characteristics ◽  
Physiological Studies ◽  
Peptone Medium

<p>Physiological studies pertaining to the effect of physical factors, carbon and nitrogen requirement of <em>Phlebiopsis gigantea</em> were conducted to know its behaviour <em>in vitro</em>. These studies have revealed interesting results regarding its growth and reproduction behaviour. The best medium for the optimum growth is Glucose-peptone medium. The optimum temperature (28°C) and pH (5.0) is required for the optimum mycelial production of <em>Phlebiopsis gigantea</em> after 12 days of incubation. The best carbon source for the growth of the fungus is D(+)Glucose least seen in Sucrose medium. The best inorganic nitrogen sources for the growth of the fungus is Sodium nitrate. The least mycelial growth of fungus is observed in ammonium acetate and ammonium nitrate. The best organic nitrogen compound for the mycelial growth of fungus is DL-threonine.</p>

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