Micellar Catalytic Effects on the Kinetics of the Ionization of Basic Amino Acid and Acidic Amino Acid Studied by the Ultrasonic Absorption Method

Human placental chorionic villi were incubated for 30 min with [3H]lysine or [3H]arginine and the distribution ratios (intracellular:extracellular concentrations) were determined. The ratios remained unchanged when Na+ in Earle's buffered salt solution was replaced with Li+. When Na+ was replaced with choline there was a significant increase is distribution ratios (lysine 1.34 +/- 0.33 v. 3.99 +/- 0.15, arginine 1.95 +/- 0.37 v. 5.05 +/- 1.16). Leucine, a neutral amino acid with a Na(+)-independent transport system, was unaffected by choline substitution. The distribution ratio for alanine, which is Na(+)-dependent, was reduced (2.50 +/- 0.41 v. 1.45 +/- 0.20). Two other quarternary amines, acetyl-beta-methylcholine and tetraethylammonium chloride (TEA) caused similar increases in the distribution ratios of the basic amino acids. Hordenine, a tertiary amine, was less effective and there was little or no effect with ephedrine, a secondary amine. The choline effect was first observable at concentrations of 105 mM. With TEA, there was a progressive increase in distribution ratios beginning at 29 mM. Lysine efflux was measured after incubation of villi with lysine in Earle's buffer or choline buffer. Lysine was rapidly released to the fresh medium with 25% more retained in choline-exposed villi. The amines may cause alterations in the kinetics of basic amino-acid transporters or may modify other aspects of placental physiology permitting an increase retention of the basic amino acids.

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ChemInform Abstract: Micellar Effect on the Kinetics of the Base Equilibrium of Amino Acids Studied by the Ultrasonic Absorption Method

ChemInform ◽

10.1002/chin.199136073 ◽

2010 ◽

Vol 22 (36) ◽

pp. no-no

Author(s):

T. YAMASHITA ◽

K. TANAKA ◽

H. YANO ◽

S. HARADA

Keyword(s):

Amino Acids ◽

Ultrasonic Absorption ◽

Absorption Method ◽

Base Equilibrium ◽

Kinetics Of ◽

Micellar Effect

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Studies on tryptophan residues of Abrus agglutinin. Stopped-flow kinetics of modification and fluorescence-quenching studies

Biochemical Journal ◽

10.1042/bj2430079 ◽

1987 ◽

Vol 243 (1) ◽

pp. 79-86 ◽

Cited By ~ 4

Author(s):

S R Patanjali ◽

M J Swamy ◽

A Surolia

Keyword(s):

Amino Acid ◽

Protein A ◽

Stopped Flow ◽

Amino Acid Residues ◽

Acidic Amino Acid ◽

Native Protein ◽

Tryptophan Residues ◽

Stopped Flow Kinetics ◽

Two Phases ◽

Kinetics Of

The presence of two essential tryptophan residues/molecule was implicated in the binding site of Abrus agglutinin [Patanjali, Swamy, Anantharam, Khan & Surolia (1984) Biochem. J. 217, 773-781]. A detailed study of the stopped-flow kinetics of the oxidation of tryptophan residues revealed three classes of tryptophan residues in the native protein. A discrete reorganization of tryptophan residues revealed three classes of tryptophan residues in the native protein. A discrete reorganization of tryptophan residues into two phases was observed upon ligand binding. The heterogeneity of tryptophan exposure was substantiated by quenching studies with acrylamide, succinimide and Cs+. Our study revealed the microenvironment of tryptophan residues to be hydrophobic, and also the presence of acidic amino acid residues in the vicinity of surface-localized tryptophan residues.

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Micellar effects on the kinetics of the hydrolysis of alkylamines studied by the ultrasonic absorption method

The Journal of Physical Chemistry ◽

10.1021/j150656a048 ◽

1984 ◽

Vol 88 (12) ◽

pp. 2671-2674 ◽

Cited By ~ 9

Author(s):

Teruyo Yamashita ◽

Hiroshige Yano ◽

Shoji Harada ◽

Tatsuya Yasunaga

Keyword(s):

Ultrasonic Absorption ◽

Absorption Method ◽

Micellar Effects ◽

Kinetics Of ◽

Hydrolysis Of

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Specific micellar catalytic effects of the protolysis of ortho-Benzoic acid derivatives studied by the ultrasonic absorption method

Journal of the Chemical Society Faraday Transactions ◽

10.1039/ft9959103525 ◽

1995 ◽

Vol 91 (19) ◽

pp. 3525

Author(s):

Teruyo Isoda ◽

Miyuki Yamasaki ◽

Hiroshige Yano ◽

Shoji Harada

Keyword(s):

Benzoic Acid ◽

Ultrasonic Absorption ◽

Absorption Method ◽

Benzoic Acid Derivatives ◽

Catalytic Effects

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The browning kinetics of the non-enzymatic browning reaction in L-ascorbic acid/basic amino acid systems

Food Science and Technology ◽

10.1590/1678-457x.08717 ◽

2017 ◽

Vol 38 (3) ◽

pp. 537-542 ◽

Cited By ~ 3

Author(s):

Ai-Nong YU ◽

Ya LI ◽

Yan YANG ◽

Ke YU

Keyword(s):

Ascorbic Acid ◽

Amino Acid ◽

Basic Amino Acid ◽

Enzymatic Browning ◽

Browning Reaction ◽

Kinetics Of

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Comparative activity of thrombin on substituted arginine and lysine esters

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1965.209.3.577 ◽

1965 ◽

Vol 209 (3) ◽

pp. 577-583 ◽

Cited By ~ 40

Author(s):

Sol Sherry ◽

Norma Alkjaersig ◽

Anthony P. Fletcher

Keyword(s):

Amino Acid ◽

Methyl Ester ◽

Reaction Kinetics ◽

Proteolytic Enzymes ◽

Basic Amino Acid ◽

Bovine Thrombin ◽

Bovine Plasma ◽

Separate Identity ◽

Kinetics Of

A number of biologically important proteolytic enzymes, particularly those involved in the reactions of blood coagulation and fibrinolysis, have the ability to hydrolyze synthetic esters of the basic amino acids, arginine, and lysine. Though synthetic amino acid esters have been used for the study of the reaction kinetics of these enzymes and for assay purposes, relatively little has been done to characterize these enzymes on the basis of their differing abilities to hydrolyze synthetic substrates. Utilizing a variety of comparably substituted arginine and lysine esters, observations were made on the reaction kinetics of several basic amino acid esterases; significant differences were noted among these enzymes, sufficient to establish their separate identity. Further characterization of the reaction of thrombin with synthetic substrates revealed that this enzyme readily hydrolyzes various substituted lysine esters as well as arginine esters. The highest Vmax was observed for the throm-bin-carbobenzoxy-lysine methyl ester reaction but the greatest affinity was observed with benzoyl-arginine methyl ester. The data also clearly establish enzymatic differences between human and bovine thrombin, and between the latter and bovine plasma thrombokinase.

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