Population genetics of glyoxalase I (E.C.4.4.1.5) in human erythrocytes

1977 ◽  
Vol 79 (1) ◽  
Author(s):  
Konrad Berg ◽  
Alexander Rodewald ◽  
Friedrich Schwarzfischer ◽  
Hans Wischerath
Keyword(s):  
Population Genetics ◽  
Human Erythrocytes ◽  
Glyoxalase I

scholarly journals Probing the active site of glyoxalase I from human erythrocytes by use of the strong reversible inhibitor S-p-bromobenzylglutathione and metal substitutions

1981 ◽  
Vol 197 (1) ◽  
pp. 67-75 ◽  
Author(s):  
Anne-Charlotte Aronsson ◽  
Siv Sellin ◽  
Gudrun Tibbelin ◽  
Bengt Mannervik
Keyword(s):  
Catalytic Activity ◽  
Linear Regression Analysis ◽  
Strong Support ◽  
Human Erythrocytes ◽  
Reversible Inhibitor ◽  
Tryptophan Residue ◽  
Glyoxalase I ◽  
Enzyme Molecule ◽  
Binding Parameters ◽  
Thiol Groups

Glyoxalase I from human erythrocytes was studied by use of the strong reversible competitive inhibitor S-p-bromobenzylglutathione. Replacements of cobalt, manganese and magnesium for the essential zinc in the enzyme were made by a new procedure involving 10% methanol as a stabilizer of the enzyme. The Km value for the adduct of methylglyoxal and glutathione was essentially unchanged by the metal substitutions, whereas the inhibition constant for S-p-bromobenzylglutathione increased from 0.08μm for the Zn-containing enzyme to 1.3, 1.7 and 2.4μm for Co-, Mn- and Mg-glyoxalase I respectively. Binding of the inhibitor to the enzyme caused quenching of the tryptophan fluorescence of the protein, from which the binding parameters could be determined by the use of non-linear regression analysis. The highest dissociation constant was obtained for apoenzyme (6.9μm). The identity of the corresponding kinetic and binding parameters of the native enzyme and the Zn2+-re-activated apoenzyme and the clear differences from the parameters of the other metal-substituted enzyme forms give strong support to the previous identification of zinc as the natural metal cofactor of glyoxalase I. Binding to apoenzyme was also shown by the use of S-p-bromobenzylglutathione as a ligand in affinity chromatography and as a protector in chemical modification experiments. The tryptophan-modifying reagent 2-hydroxy-5-nitrobenzyl bromide caused up to 85% inactivation of the enzyme. After blocking of the thiol groups (about 8 per enzyme molecule) 6.1 2-hydroxy-5-nitrobenzyl groups were incorporated. Inclusion of S-p-bromobenzylglutathione with the modifying reagent preserved the catalytic activity of the enzyme completely and decreased the number of modified residues to 4.4 per enzyme molecule. The findings indicate the presence of one tryptophan residue in the active centre of each of the two subunits of the enzyme. Thiol groups appear not to be essential for catalytic activity. The presence of at least two categories of tryptophan residues in the protein was also shown by quenching of the fluorescence by KI.

Population genetics of red cell glyoxalase I (E.C.: 4.4.1.5)

1975 ◽  
Vol 28 (2) ◽  
pp. 175-176 ◽  
Author(s):  
J. Kömpf ◽  
S. Bissbort
Keyword(s):  
Population Genetics ◽  
Glyoxalase I ◽  
Red Cell

On the population genetics of the red cell glyoxalase I (GLO)

1977 ◽  
Vol 39 (3) ◽  
pp. 303-304 ◽  
Author(s):  
P. St�hlmacher ◽  
W. Haferland
Keyword(s):  
Population Genetics ◽  
Glyoxalase I ◽  
Red Cell

Partial transition-state inhibitors of glyoxalase I from human erythrocytes, yeast and rat liver

1985 ◽  
Vol 829 (1) ◽  
pp. 109-118 ◽  
Author(s):  
Kenneth T. Douglas ◽  
Dhanesh I. Gohel ◽  
Iffat N. Nadvi ◽  
A.Joy Quilter ◽  
Andrew P. Seddon
Keyword(s):  
Transition State ◽  
Rat Liver ◽  
Human Erythrocytes ◽  
Glyoxalase I

[85] Glyoxalase I from human erythrocytes

1982 ◽  
pp. 535-541 ◽  
Author(s):  
Bengt Mannervik ◽  
Anne-Charlotte Aronsson ◽  
Gudrun Tibbelin
Keyword(s):  
Human Erythrocytes ◽  
Glyoxalase I

Elemental analysis of human erythrocytes

1989 ◽  
Vol 47 ◽  
pp. 242-243
Author(s):  
S. A. Livesey ◽  
A. A. del Campo ◽  
E. S. Griffey ◽  
D. Ohlmer ◽  
T. Schifani ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Elemental Analysis ◽  
Human Erythrocyte ◽  
Spectroscopic Analysis ◽  
Model System ◽  
Human Erythrocytes ◽  
List Type ◽  
Chemical Fixation ◽  
Ethanol Dehydration ◽  
Lowicryl K4m

The aim of this study is to compare methods of sample preparation for elemental analysis. The model system which is used is the human erythrocyte. Energy dispersive spectroscopic analysis has been previously reported for cryofixed and cryosectioned erythrocytes. Such work represents the reference point for this study. The use of plastic embedded samples for elemental analysis has also been documented. The work which is presented here is based on human erythrocytes which have been either chemically fixed and embedded or cryofixed and subsequently processed by a variety of techniques which culminated in plastic embedded samples.Heparinized and washed erythrocytes were prepared by the following methods for this study :(1). Chemical fixation in 4% paraformaldehyde/0.25% glutaraldehyde/0.2 M sucrose in 0.1 M Na cacodylate, pH 7.3 for 30 min, followed by ethanol dehydration, infiltration and embedding in Lowicryl K4M at -20° C.

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