scholarly journals ATP-Dependent Export of Neutral Amino Acids by Vacuolar Membrane Vesicles ofSaccharomyces cerevisiae

2012 ◽  
Vol 76 (9) ◽  
pp. 1802-1804 ◽  
Author(s):  
Masaya ISHIMOTO ◽  
Naoko SUGIMOTO ◽  
Takayuki SEKITO ◽  
Miyuki KAWANO-KAWADA ◽  
Yoshimi KAKINUMA
Keyword(s):  
Amino Acids ◽  
Membrane Vesicles ◽  
Vacuolar Membrane ◽  
Neutral Amino Acids

Ygr125w/Vsb1-dependent accumulation of basic amino acids into vacuoles of Saccharomyces cerevisiae

2021 ◽  
Author(s):  
Miyuki Kawano-Kawada ◽  
Haruka Ichimura ◽  
Shota Ohnishi ◽  
Yusuke Yamamoto ◽  
Yumi Kawasaki ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Transmembrane Helix ◽  
Membrane Vesicles ◽  
Vacuolar Membrane ◽  
Expression Plasmid ◽  
Basic Amino Acids ◽  
Uptake Activity ◽  
Hydrophilic Region ◽  
Aspartate Residue

Abstract The Ygr125w was previously identified as a vacuolar membrane protein by a proteomic analysis. We found that vacuolar levels of basic amino acids drastically decreased in ygr125wΔ cells. Since N- or C-terminally tagged Ygr125w was not functional, an expression plasmid of YGR125w with HA3-tag inserted in its N-terminal hydrophilic region was constructed. Introduction of this plasmid into ygr125w∆ cells restored the vacuolar levels of basic amino acids. We successfully detected the uptake activity of arginine by the vacuolar membrane vesicles depending on HA3-YGR125w expression. A conserved aspartate residue in the predicted first transmembrane helix (D223) was indispensable for the accumulation of basic amino acids. YGR125w has been recently reported as a gene involved in vacuolar storage of arginine; and it is designated as VSB1. Taken together, our findings indicate that Ygr125w/Vsb1 contributes to the uptake of arginine into vacuoles and vacuolar compartmentalization of basic amino acids.

scholarly journals A PQ-loop protein Ypq2 is involved in the exchange of arginine and histidine across the vacuolar membrane of Saccharomyces cerevisiae

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Miyuki Kawano-Kawada ◽  
Kunio Manabe ◽  
Haruka Ichimura ◽  
Takumi Kimura ◽  
Yuki Harada ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Kinetic Analysis ◽  
Membrane Vesicles ◽  
Vacuolar Membrane ◽  
Coupled Systems ◽  
Gene Encoding ◽  
Proline Residue ◽  
Uptake Activity ◽  
Exchange Activity

Abstract In nutrient-rich conditions, basic amino acids are actively accumulated into the vacuoles by H+-coupled transporters in Saccharomyces cerevisiae. In addition to the H+-coupled systems, the existence of an exchanger for arginine and histidine was indicated by kinetic analysis using isolated vacuolar membrane vesicles; however, the gene(s) involved in the activity has not been identified. Here, we show that the uptake activity of arginine driven by an artificially imposed histidine gradient decreased significantly by the disruption of the gene encoding vacuolar PQ-loop protein Ypq2, but not by those of Ypq1 and Ypq3. The exchange activity was restored by the expression of YPQ2. Furthermore, the substitution of a conserved proline residue, Pro29, in Ypq2 greatly decreased the exchange activity. These results suggest that Ypq2 is responsible for the exchange activity of arginine and histidine across the vacuolar membrane, and the conserved proline residue in the PQ-loop motif is required for the activity.

Regulation of l-methionine and l-lysine uptake in chicken jejunal brush-border membrane by dietary methionine

1999 ◽  
Vol 277 (6) ◽  
pp. R1654-R1661 ◽  
Author(s):  
Juan F. Soriano-García ◽  
Mònica Torras-Llort ◽  
Miquel Moretó ◽  
Ruth Ferrer
Keyword(s):  
Amino Acids ◽  
Brush Border ◽  
Brush Border Membrane ◽  
Membrane Vesicles ◽  
Transport Systems ◽  
Food Utilization ◽  
Maximal Velocity ◽  
Neutral Amino Acids ◽  
System L ◽  
Methionine Supplementation

In the chicken intestine,l-methionine is transported by systems that are specific for neutral amino acids (L- and B-like) and by systems that can also transport cationic amino acids (y+m and b0,+-like). These four uptake pathways have been investigated in brush-border membrane vesicles from the jejunum of chickens fed a diet enriched with 0.4%l-methionine. Methionine supplementation from the 1st to the 6th wk of age has no effect on body weight or on the efficiency of food utilization. The kinetic analysis of l-methionine influx across the transport systems specific for neutral amino acids shows, for system L, no dietary effect on the Michaelis constant ( K m) and a 30% reduction in maximal velocity ( V max); for system B it shows a decrease in K m (30%) and in V max (51%). Transport systems shared by cationic and neutral amino acids show no dietary effect on b0,+ activity and a significant reduction in y+m V max, similar forl-methionine andl-lysine, both in the absence and in the presence of Na+(l-methionine, 30 and 26% reduction; l-lysine, 19 and 28% reduction, respectively). The downregulation induced byl-methionine supplementation may be an adaptive response to reduce the risk of intoxication by dietary excess of l-methionine. These results support the view that the toxicity of the supplemented substrate can be an important factor in the regulation of amino acid transport by dietary content.

Characteristics of cysteine uptake in intestinal basolateral membrane vesicles

1984 ◽  
Vol 247 (4) ◽  
pp. G394-G401 ◽  
Author(s):  
L. H. Lash ◽  
D. P. Jones
Keyword(s):  
Amino Acids ◽  
Basolateral Membrane ◽  
Membrane Vesicles ◽  
Transport Systems ◽  
Side Chains ◽  
Dependent Manner ◽  
Basolateral Membrane Vesicles ◽  
Concentration Dependent Manner ◽  
Neutral Amino Acids ◽  
Specificity Pattern

Uptake of cysteine in intestinal basolateral membrane vesicles was independent of Na+, was sensitive to medium osmolarity, exhibited saturation kinetics, and was selectively inhibited by other amino acids in a concentration-dependent manner, indicating transport by a carrier-mediated process. The kinetics indicated the existence of two transport systems: a high- and a low-Km system with Km and Vmax values that differed by greater than one order of magnitude. The substrate specificity pattern indicated two principal transport systems for cysteine: one corresponding to the high-Km system and one to the low-Km system. The high-Km system was inhibited primarily by neutral amino acids with small or polar side chains (alanine, serine, threonine, and glycine), resembling the ASC system in its specificity. The low-Km system was inhibited primarily by neutral amino acids with large, nonpolar side chains (leucine, phenylalanine, and methionine) and by the leucine analogue beta-2-aminobicyclo(2,2,1)heptane-2-carboxylic acid, identifying it as the L system. The two systems also exhibited trans stimulation, but only with those amino acids that caused cis inhibition.

Atypical amino acids inhibit histidine, valine, or lysine transport into rat brain

1983 ◽  
Vol 245 (4) ◽  
pp. R556-R563 ◽  
Author(s):  
J. K. Tews ◽  
A. E. Harper
Keyword(s):  
Amino Acids ◽  
Rat Brain ◽  
Blood Brain Barrier ◽  
Brain Slices ◽  
Aromatic Amino Acids ◽  
Brain Barrier ◽  
Basic Amino Acids ◽  
Large Neutral Amino Acids ◽  
Neutral Amino Acids ◽  
Single Meal

Transport of histidine, valine, or lysine into rat brain slices and across the blood-brain barrier (BBB) was determined in the presence of atypical nonprotein amino acids. Competitors of histidine and valine transport in slices were large neutral amino acids including norleucine, norvaline, alpha-aminooctanoate, beta-methylphenylalanine, and alpha-aminophenylacetate. Less effective were aromatic amino acids with ring substituents; ineffective were basic amino acids and omega-amino isomers of norleucine and aminooctanoate. Lysine transport was moderately depressed by homoarginine or ornithine plus arginine; large neutral amino acids were also similarly inhibitory. Histidine or valine transport across the BBB was also strongly inhibited by large neutral amino acids that were the most effective competitors in the slices (norvaline, norleucine, alpha-aminooctanoate, and alpha-aminophenylacetate); homoarginine and 8-aminooctanoate were ineffective. Homoarginine, ornithine, and arginine almost completely blocked lysine transport, but the large neutral amino acids were barely inhibitory. When rats were fed a single meal containing individual atypical large neutral amino acids or homoarginine, brain pools of certain large neutral amino acids or of arginine and lysine, respectively, were depleted.

scholarly journals Characteristics of system ASC for transport of neutral amino acids in the isolated rat hepatocyte.

1981 ◽  
Vol 256 (7) ◽  
pp. 3304-3312
Author(s):  
M.S. Kilberg ◽  
M.E. Handlogten ◽  
H.N. Christensen
Keyword(s):  
Amino Acids ◽  
Rat Hepatocyte ◽  
Neutral Amino Acids ◽  
Isolated Rat
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