Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: CAS:107-95-9 (beta-alanine)
 2,037 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There were altogether fourteen amino acids in leaf sheath and culm of wheat infected with Puccinia graminis tritici, especially in and around uredial and telial pustules. Valine, tyrosine, and proline, due to their exclusive presence in uredial pustules on leaf sheath and culm of wheat, were involved in the eruption of uredospores of P. graminis tritici. Glutamic acid and dl-threonine were, however, involved in a different manner during uredospore differentiation; their amounts diminishesd parallel to sporulation. The other amino compounds, detected in and around uredial and telial pustules on leaf sheaths and culms, were l-leucine/isoleucine, beta-phenylalanine, beta-alanine, glycine, serine, aspartic acid, homoserine, and glutamine. The amounts of these amino acids either remained the same or were lowered during uredo- and teluto-spores formation, except for serine which increased in its amount. The depletion of these amino compounds indicated their metabolic activity and utilization for uredo- and teleuto-spores differentiation of P. graminis tritici. Sucrose, glucose, and fructose, among sugars, were also utilized as their amounts diminished, for uredo- and teleuto-spores formation.
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PMID:Changes in the composition of free amino acids and sugars of leaf sheath and culm of wheat during uredospore and teleutospore formation of Puccinia graminis tritici. 742 30

In response to infection by the rust pathogen Uromyces fabae the different tissues of broad bean (Vicia faba L.) showed varied pattern of amino acid metabolism; some of them being exclusively present in a particular region only. In the inflorescence tissue, for example, tryptophan, glycine, aspartic acid, serine, proline, and arginine were present. In the stem, however, the amino acids, present during and after infection, were tryptophan, serine, glutamine, homoserine, and dl-alanine. Post-infectionally induced amino compounds, lysine, histidine, vomoserine, proline, tyrosine and dl-threonine, were found in the leaves; in the petiole serine and histidine were the only two such amino acids. Out of these amino acids only histidine and proline, with their specific presence and activity, encouraged uredospore differentiation. L-cysteine, too, by being actively utilized, served as promoter of uredosporulation. Asparagine and methionine showed moderate to heavy depletion during bean tissue infection. On the other hand, l-leucine/isoleucine, beta-alanine, valine, and glutamic acid showed moderate to pronounced increase during pathogenic establishment. Concomitant to uredospore differentiation there was a drastic lowering in the amount of sucrose in leaf and petiole tissue. The amount of glucose also declined during pathogenesis.
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PMID:Variations in amino acids and sugars in different tissues of broad bean (Vicia faba L.) during the pathogenesis of Uromyces fabae (Pers.) de Bary. 742 31

The composition of various amino acids and related compounds in the aorta, ventricle, atria, liver, kidney, pancreas, bronchi and adrenals of rats is presented. These patterns are qualitatively similar, but quantitatively different. Stress changed these patterns. In the aorta, alpha-aminobutyric acid and ammonia are decreased. In the ventricle, phosphoserine and red. Glutathione are increased; and ammonia, arginine, asparagine, carnosine, ethanolamine, glutamic acid, glutamine, lysine, phosphoethanolamine and taurine are decreased. In the atria, alpha-aminobutyric acid, aspartic acid, ethanolamine and red. glutathione are increased; and ammonia is decreased. In the liver, alpha-aminobutyric acid, cystine, isoleucine, red. glutathione, methionine and phenylalanine are increased. In the kidney, ethanolamine is increased; and beta - aminobutyric acid, citrulline, cystathionine, glutamic acid, glycine and tryptophan are decreased. In the pancreas, alpha-aminoadipic acid, ox. glutathione, leucine, glutamine, 1-methylhistidine, phenylalanine, phosphoserine, tryptophan and valine are increased; and ammonia, cystine and aspartic acid are decreased. In the adrenal glands, anserine, glutamic acid, glutamine and ox. glutathione are increased; and arginine is decreased. In the bronchi, ethanolamine and beta-alanine are increased and alpha-aminobutyric acid and ox. glutathione are decreased. Thus, stress affects certain amino compounds but changes are substance and tissue specific and independent of changes seen in the plasma.
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PMID:Effect of stress on amino acids and related compounds in various tissues of the rat. 747 20

We determined the extent of Na(+)-independent, proton-driven amino acid transport in human intestinal epithelia (Caco-2). In Na(+)-free conditions, acidification of the apical medium (apical pH 6.0, basolateral pH 7.4) is associated with a saturable net absorption of glycine. With Na(+)-free media and apical pH set at 6.0, (basolateral pH 7.4), competition studies with glycine indicate that proline, hydroxyproline, sarcosine, betaine, taurine, beta-alanine, alpha-aminoisobutyric acid (AIB), alpha-methylaminoisobutyric acid (MeAIB), tau-amino-n-butyric acid and L-alanine are likely substrates for pH-dependent transport in the brush border of Caco-2 cells. Both D-serine and D-alanine were also substrates. In contrast leucine, isoleucine, valine, phenylalanine, methionine, threonine, cysteine, asparagine, glutamine, histidine, arginine, lysine, glutamate and D-aspartate were not effective substrates. Perfusion of those amino acids capable of inhibition of acid-stimulated net glycine transport at the brush-border surface of Caco-2 cell monolayers loaded with the pH-sensitive dye 2',7'-bis(2-carboxyethyl-5(6)-carboxyfluorescein) (BCECF) caused cytosolic acidification consistent with proton/amino acid symport. In addition, these amino acids stimulate an inward short-circuit current (Isc) in voltage-clamped Caco-2 cell monolayers in Na(+)-free media (pH 6.0). Other amino acids such as leucine, isoleucine, phenylalanine, tryptophan, methionine, valine, serine, glutamine, asparagine, D-aspartic acid, glutamic acid, cysteine, lysine, arginine and histidine were without effect on both pHi and inward Isc. In conclusion, Caco-2 cells express a Na(+)-independent, H(+)-coupled, rheogenic amino acid transporter at the apical brush-border membrane which plays an important role in the transepithelial transport of a range of amino acids across this human intestinal epithelium.
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PMID:The role of the proton electrochemical gradient in the transepithelial absorption of amino acids by human intestinal Caco-2 cell monolayers. 756 25

1. In sensitized guinea-pigs, the effects of gamma-aminobutyric acid (GABA) and GABAmimetic drugs have been investigated on tracheal segments contracted by cumulative application of an allergen (ovoalbumin, OA) and on serosal mast cells. The same drugs have also been tested on activation of alveolar macrophages isolated from unsensitized guinea-pigs. 2. Superfusion with GABA (1-1000 microM) reduced the contraction intensity of tracheal strips. The effect of GABA (100 microM) was not affected by the carrier blockers, nipecotic acid and beta-alanine (300 microM each). It was mimicked by the GABAB agonist (-)-baclofen (100 microM) but not 3-aminopropanephosphinic acid (100 microM, 3-APA). The GABAA agonist, isoguvacine (100 microM) did not exert any effect. GABA (10 microM)-induced inhibition of tracheal contractions was reduced by the GABAB antagonist, 2-hydroxysaclofen (100 microM, 2-HS), but not by the GABAA antagonist, bicuculline (30 microM). 3. The reduction in contraction intensity induced by GABA (100 microM) was prevented by a 40 min preincubation of tracheal strips with capsaicin (10 microM), but not tetrodotoxin (TTX, 0.3 microM). The effect of GABA (1000 microM) was absent after preincubation with indomethacin (2.8 microM) but unmodified when nordihydroguaiaretic acid (NDGA, 3.3 microM) was used. Finally, removal of the epithelium prevented the GABA effect. 4. Anaphylactic histamine release from serosal mast cells isolated from sensitized animals was not affected either by GABA (10-1000 microM) or the selective receptor agonists (-)-baclofen (0.1-1000 microM) and isoguvacine (10-1000 microM). The release of platelet-activating factor (PAF) from alveolar macrophages stimulated by formyl-Met-Leu-Phe (FMLP; 1 microM) was modified neither by GABA (100 microM)nor by (-)-baclofen (100microM).5. In conclusion, these data show that GABA can inhibit allergic phenomena in the guinea-pig airways through activation of GABAB receptors. An involvement of neuropeptidergic sensory structures is suggested but a role for epithelial cells and arachidonate metabolites is not definitely proved.
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PMID:GABA-mediated inhibition of the anaphylactic response in the guinea-pig trachea. 758 47

Papain, a prototype cysteine proteinase, shows a pronounced kinetic preference for substrates and inhibitors based on the Ac-L-Phe-Gly-structural motif. Replacing the L-Phe at position P2 with D-Phe, or with a less hydrophobic residue such as Leu or Met, results in decreases of substrate or inhibitory activity of up to 400-fold. In this study we examined the effect of homologating the P1 glycine moiety to beta-alanine in the context of specific ester and amide substrates, peptidyl nitrile and -aldehyde transition state analog inhibitors, and peptidyl Michael acceptors as irreversible affinity labels. Papain discriminates extremely strongly (i.e., from 1000-fold to > or = 29,000-fold) against the 'homologs' based on beta-alanine at P1 compared to 'analogs' based on glycine at P1. However, with highly reactive ligands such as p-nitrophenyl esters, homolog/analog discrimination is greatly reduced (i.e., < or = 10-fold). These observations are interpreted in terms of (1) cooperativity between several non-covalent enzyme-ligand interactions and the covalent interaction of the ligand P1 moiety with Cys-25 of papain, (2) the decreased ability of homologs to utilize these cooperative interactions optimally because of their extended size, and (3) a decrease in the importance of the cooperative interactions as the intrinsic chemical reactivity of the ligand increases. Some implications of this analog vs. homolog discrimination for peptidyl disulfide and peptidyl chloromethane probes of protease specificity and mechanism are discussed.
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PMID:Effects of ligand homologation and ligand reactivity on the apparent kinetic specificity of papain. 761 52

Agonist binding to the inhibitory glycine receptor (GlyR) initiates the opening of a chloride-selective channel that modulates the neuronal membrane potential. Point mutations of the GlyR, substituting Arg-271 with either Leu or Gln, have been shown to underlie the inherited neurological disorder startle disease (hyperekplexia). We show that these substitutions result in the redistribution of GlyR single-channel conductances to lower conductance levels. Additionally, the binding of the glycinergic agonists beta-alanine and taurine to mutated GlyRs does not initiate a chloride current, but instead competitively antagonizes currents activated by glycine. These findings are consistent with mutations of Arg-271 resulting in the uncoupling of the agonist binding process from the channel activation mechanism of the receptor.
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PMID:Mutation of an arginine residue in the human glycine receptor transforms beta-alanine and taurine from agonists into competitive antagonists. 782 34

The present study extends the observations of chloride-dependent intestinal amino acid carriers to the guinea pig and the rat using the technique of in vitro influx across the brush-border membrane of intact epithelium. Transport rates of D-glucose and L-amino acids are lowest in guinea pig proximal small intestine and are constant from midjejunum through distal ileum, except for leucine. The guinea pig possesses a sodium- and chloride-dependent, high-affinity, very low-capacity carrier of beta-amino acids for which taurine and beta-alanine compete and for which the Na(+)-taurine activation stoichiometry is 2.1 +/- 0.3:1. The imino acid carrier of the guinea pig is also chloride dependent with a Na(+)-Cl(-)-2-methylamino-isobutyric acid activation stoichiometry of 1.8 +/- 0.1:0.7 +/- 0.3:1. In contrast, the rat imino acid carrier is chloride independent and transport rates vary insignificantly along the small intestine. The rat taurine carrier has its maximal transport rate in midjejunum. It is chloride dependent but does not transport beta-alanine.
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PMID:Chloride-dependent intestinal transport of imino and beta-amino acids in the guinea pig and rat. 816 Aug 97

Skate erythrocytes swell in a hypotonic medium and then reduce their volume mainly by releasing the beta-amino acids taurine and beta-alanine. Although these amino acids exhibit a net efflux, Na(+)-independent influx is also increased. Both the reduction in cell volume and increase in amino acid transport are inhibited by several inhibitors of band 3-mediated anion transport, including 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) [L. Goldstein and S. R. Brill, Am. J. Physiol. 260 (Regulatory Integrative Comp. Physiol. 29): R1014-R1020, 1991]. The objective of the present investigation was to further characterize the mechanism of volume-activated amino acid transport. Na(+)-independent amino acid uptake was studied because of the ease in controlling amino acid concentrations. Na(+)-independent taurine uptake was observed to be linear over a range of 0.1-15 mM and was not inhibited by 10 mM beta-alanine, suggesting that the transporter may be a channel rather than a carrier. The uptake of a variety of amino acids was examined to characterize the size of the putative channel. Glycine, beta-alanine, taurine, proline, gamma-aminobutyric acid (GABA), and threonine exhibited volume-activated transport that was DIDS inhibited, whereas aspartic acid, leucine, methionine, and ornithine were not transported. On the basis of the size of these amino acids, it appears that molecules containing eight or fewer major atoms and having a molecular mass of < 125-131 Da are transported during volume activation but larger molecules are not. We estimate the size of the channel to be 5.7-6.3 A in diameter.
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PMID:Volume-regulatory amino acid transport in erythrocytes of the little skate, Raja erinacea. 834 84

The effect of phorbol 12-myristate 13-acetate (PMA), a phorbol ester known to stimulate protein kinase C, on taurine transport was studied in the human colon carcinoma cell line HT-29. PMA (1 microM) was found to inhibit taurine uptake in confluent monolayers of this cell line by approximately 70% after pretreatment of the cells with the compound for 1 h (IC50 = 42.7 +/- 2.6 nM). The inhibitory effect of PMA on the taurine transporter could be confirmed by using beta-alanine, another substrate for the transporter. Kinetic analysis of taurine uptake indicated that the PMA effect was associated with a decrease in the maximal velocity (954 +/- 26 vs. 676 +/- 28 pmol.10 min-1.mg of protein-1) and an increase in the Michaelis-Menten constant (9.8 +/- 0.5 vs. 13.3 +/- 1.0 microM). The inhibition of taurine uptake could be blocked by cotreatment of the cultures with staurosporine, an inhibitor of protein kinase C. The inactive phorbol ester 4 alpha-phorbol 12,13-didecanoate had no effect. Treatment of the cells with PMA did not alter the uptake of leucine and lysine, stimulated the uptake of aspartic acid, and inhibited the uptake of proline. The PMA effect on taurine uptake was not prevented by cycloheximide, actinomycin D, colchicine, or cytochalasin D. Comparison of the taurine transport activity in HT-29 cells with that in Caco-2, another human colon carcinoma cell line, revealed that the latter cell line also expressed the taurine transporter but at a much reduced level (about one-fifth compared with HT-29).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regulation of taurine transport in human colon carcinoma cell lines (HT-29 and Caco-2) by protein kinase C. 849 20


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