Qualitative/chiral sensing of amino acids by naked-eye fluorescence change based on morphological transformation and hierarchizing in supramolecular assemblies of pyrene-conjugated glycolipids

2015 ◽  
Vol 51 (55) ◽  
pp. 11104-11107 ◽  
Author(s):  
Naohiro Kameta ◽  
Mitsutoshi Masuda ◽  
Toshimi Shimizu

Supramolecular assemblies exhibited fluorescence-color changes in response to not only a specific amino acid but also the chirality of the recognized amino acid.

1990 ◽  
Vol 97 (3) ◽  
pp. 479-485
Author(s):  
J.R. Jara ◽  
J.H. Martinez-Liarte ◽  
F. Solano ◽  
R. Penafiel

The uptake of L-Tyr by B16/F10 malignant melanocytes in culture has been studied. These melanoma cells can either be depleted of amino acids by 1 h preincubation in Hanks' isotonic medium or preloaded with a specific amino acid by 1 h preincubation in the same solution containing 2 mM of the amino acid to be preloaded. By means of these pretreatments, it is shown that the rate of L-Tyr uptake is greatly dependent on the content of other amino acids inside the cells. The L-Tyr uptake is higher in cells preloaded with amino acids transported by the L and ASC systems than in cells depleted of amino acids or preloaded with amino acids transported by the A system. It is concluded that L-Tyr is mainly taken up by an exchange mechanism with other amino acids mediated by the L1 system, although the ASC system can also participate in the process. In agreement with that, the homo-exchange performed by cells preloaded with unlabelled L-Tyr is more efficient than any other hetero-exchange, although L-Dopa, the product of tyrosine hydroxylation in melanin synthesis, is almost as efficient as L-Tyr. Apart from aromatic amino acids, melanoma cells preloaded with L-Met and L-His also yield a high initial rate of L-Tyr uptake. The results herein suggest that melanoma cells do not have transport systems specific for L-Tyr, even if this amino acid is needed to carry out the differential pathway of this type of cells, melanosynthesis.


Jurnal Kimia ◽  
2016 ◽  
Author(s):  
Dita Rizkiyanti ◽  
Ni Made Suaniti ◽  
Ketut Ratnayani

Seeds are a source of high protein when compared with other parts of the plant. Compared to soy bean, the use of winged bean seeds, tamarind seeds, moringa seeds as protein sources are still very limited. Protein composed of several amino acids bond together to form a polypeptide. Some amino acids have been investigated to act as stimulating insulin secretion, namely, arginine, alanine, phenylalanine, isoleucine, and lysine. The aim of this study was to determine the potential content of amino acids stimulating the secretion of insulin in winged bean seeds, tamarind seeds, and moringa seeds. Based on the total content of amino acids in each seeds, the results showed that moringa seeds have the highest levels of total amino acids stimulating insulin secretion (16.4%), followed by winged bean seeds (16.2%), and tamarind seeds (12.1%). But if seen by the levels of each amino acid, the winged bean seeds on average had the highest amino acid content. The highest levels of arginine, alanine, phenylalanine, isoleucine, and leucine were found in winged bean seeds, while only one specific amino acid i.e. lysine was found to be the highest level on moringa seeds. It can be concluded that the most potential seeds as a source of amino acids stimulating insulin was the winged bean seeds, that will be useful in the prevention or treatment of diabetes mellitus.


1950 ◽  
Vol 28c (1) ◽  
pp. 1-6 ◽  
Author(s):  
R. H. Wallace ◽  
A. G. Lochhead

A study was made of the more specific amino acid requirements of bacteria from the rhizospheres of clover, flax, and wheat plants for which a chemically defined medium containing 23 amino acids provided essentials for maximum growth. Of seven groups of amino acids, the sulphur-containing group (cysteine, methionine, and taurine) was found to be of special significance, the omission of this group resulting in a pronounced decrease in the percentage of organisms able to develop. Further study of organisms dependent upon this group of amino acids for growth showed methionine to be by far the most essential compound. While evident for bacteria from the rhizosphere of all three crops, the effect was more pronounced in the case of clover than with flax or wheat.


Proceedings ◽  
2019 ◽  
Vol 41 (1) ◽  
pp. 18
Author(s):  
Edurne Avellanal-Zaballa ◽  
Ágata Ramos-Torres ◽  
Alejandro Prieto-Castañeda ◽  
Fernando García-Garrido ◽  
Jorge Bañuelos ◽  
...  

Herein, we describe the synthetic route to access a red-emitting BODIPY from its α-diformylated precursor. The photophysical signatures of this dye are sensitive to the presence of thiol-containing amino acids (like cysteine, homocysteine, and glutathione) in the surrounding environment. This sensor provides up to three detection channels to monitor and quantify these biomolecules, even at low concentrations (down to micromolar). Moreover, owing to the pronounced splitting of the spectral band profile induced by these amino acids, the detection can be visualized following just the evolution of the fluorescence color by the naked eye.


1957 ◽  
Vol 3 (1) ◽  
pp. 73-80 ◽  
Author(s):  
T. M. B. Payne ◽  
J. W. Rouatt ◽  
A. G. Lochhead

Twenty-two of 30 representative soil bacteria having simple nutritional requirements, in that they showed maximum development in a medium of inorganic salts and sugar, were found to be able to synthesize a variety of amino acids, though in no single case were more than four ninhydrin-positive substances found. The culture filtrates permitted the growth of amino-acid-requiring bacteria to the extent that they contained the specific amino acid or acids required by strains of the latter group. The findings point to an associative action between these nutritional groups of soil organisms and suggest that the preferential stimulation in the rhizosphere of bacteria requiring amino acids may be ascribed in part to the ability of the other group of bacteria, which are numerically increased in the rhizosphere, to synthesize amino acids.


1993 ◽  
Vol 44 (5) ◽  
pp. 959 ◽  
Author(s):  
CA Stewart ◽  
DG Masters ◽  
IH Williams ◽  
PJ Connell

Provision of sulfur-containing amino acids into the abomasum has increased wool production in non-reproducing sheep and, on the basis of such studies, they have generally been considered as the primary limiting nutrients for wool growth. The specific amino acid needs of reproducing ewes were investigated in the current study. Three groups of pregnant ewes were fitted with temporary abomasal fistulae. For the last 3-4 weeks of pregnancy and the first 3 weeks of lactation, solutions containing sodium hydroxide (as a carrier) or methionine or a mixture of valine, arginine, lysine and threonine (VALT) were injected into the abomasum twice per day. The injection of methionine did not increase protein deposition during pregnancy; this was indicated by the failure of the treatment to lower the concentration of other amino acids in plasma, or increase liveweight, lamb birth weight or wool growth. Responses in early lactation were different with the methionine injected sheep having a lower concentration of free lysine, valine, alanine and serine in plasma, indicating an increased rate of protein deposition, and a faster growth rate in the ewes. Injections of VALT caused a decrease in the concentration of cystine and methionine in plasma and depressed wool growth and tensile strength. Theresults indicate that a lack of methionine was not limiting protein deposition during late pregnancy, but may have been during early lactation. Valine, arginine, lysine and threonine were not the primary limiting amino acids in late pregnancy or early lactation.


2019 ◽  
Vol 32 (11) ◽  
pp. 503-511
Author(s):  
Thuy Duong Nguyen ◽  
Yutaka Saito ◽  
Tomoshi Kameda

Abstract In protein engineering, generation of mutagenesis libraries is a key step to study the functions of mutants. To generate mutants with a desired composition of amino acids (AAs), a codon consisting of a mixture of nucleotides is widely applied. Several computational methods have been proposed to calculate a codon nucleotide composition for generating a given amino acid profile based on mathematical optimization. However, these previous methods need to manually tune weights of amino acids in objective functions, which are time-consuming and, more importantly, lack publicly available software implementations. Here, we develop CodonAdjust, a software to adjust a codon nucleotide composition for mimicking a given amino acid profile. We propose different options of CodonAdjust, which provide various customizations in practical scenarios such as setting a guaranteeing threshold for the frequencies of amino acids without any manual tasks. We demonstrate the capability of CodonAdjust in the experiments on the complementarity-determining regions (CDRs) of antibodies and T-cell receptors (TCRs) as well as millions of amino acid profiles from Pfam. These results suggest that CodonAdjust is a productive software for codon design and may accelerate library generation. CodonAdjust is freely available at https://github.com/tiffany-nguyen/CodonAdjust. Paper edited by Dr. Jeffery Saven, Board Member for PEDS.


eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Hugh K Haddox ◽  
Adam S Dingens ◽  
Sarah K Hilton ◽  
Julie Overbaugh ◽  
Jesse D Bloom

The immediate evolutionary space accessible to HIV is largely determined by how single amino acid mutations affect fitness. These mutational effects can shift as the virus evolves. However, the prevalence of such shifts in mutational effects remains unclear. Here, we quantify the effects on viral growth of all amino acid mutations to two HIV envelope (Env) proteins that differ at>100 residues. Most mutations similarly affect both Envs, but the amino acid preferences of a minority of sites have clearly shifted. These shifted sites usually prefer a specific amino acid in one Env, but tolerate many amino acids in the other. Surprisingly, shifts are only slightly enriched at sites that have substituted between the Envs—and many occur at residues that do not even contact substitutions. Therefore, long-range epistasis can unpredictably shift Env’s mutational tolerance during HIV evolution, although the amino acid preferences of most sites are conserved between moderately diverged viral strains.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Júlia Santos ◽  
Cecília Leão ◽  
Maria João Sousa

Ammonium (NH4+) leads to chronological life span (CLS) shortening inSaccharomyces cerevisiaeBY4742 cells, particularly evident in cells starved for auxotrophy-complementing amino acids (leucine, lysine, and histidine) simultaneously. Here, we report that the effect ofNH4+on aging yeast depends on the specific amino acid they are deprived of. Compared with no amino acid starvation, starvation for leucine alone or in combination with histidine resulted in the most pronouncedNH4+-induced CLS shortening, whereas starvation for lysine, alone or in combination with histidine resulted in the least sensitivity toNH4+. We also show thatNH4+-induced CLS shortening is mainly mediated by Tor1p in cells starved for leucine or histidine but by Ras2p in cells starved for lysine, and in nonstarved cells. Sch9p protected cells from the effect ofNH4+under all conditions tested (starved or nonstarved cells), which was associated with Sch9p-dependent Hog1p phosphorylation. Our data show thatNH4+toxicity can be modulated through manipulation of the specific essential amino acid supplied to cells and of the conserved Ras2p, Tor1p, and Sch9p regulators, thus providing new clues to the development of environmental interventions for CLS extension and to the identification of new therapeutic targets for diseases associated with hyperammonemia.


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