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Journal ArticleDOI

A reinvestigation of inhibitors of glyoxalase I

01 Dec 1987-Journal of Biosciences (Springer India)-Vol. 12, Iss: 4, pp 405-414
TL;DR: It is found that nucleotides such as ATP, GTP and different classes of other reagents based on transition state analogy (D-isoascorbate, dihydroxyfumaric acid, rhodizonic acid) do not inhibit yeast or goat liver glyoxalase I.
Abstract: It has been reported earlier that nucleotides, nucleosides and a series of structurally related compounds as well as compounds based on transition state analogy inhibit yeast glyoxalase I. In our study on the metabolic regulation of glyoxalase I, we have found that nucleotides such as ATP, GTP and different classes of other reagents based on transition state analogy (D-isoascorbate, dihydroxyfumaric acid, rhodizonic acid) do not inhibit yeast or goat liver glyoxalase I. The reported inhibition of glyoxalase I by these compounds has been found to be due to the interference of these compounds with the absorbancy at 240 nm of S-D-lactoylglutathione formed by the glyoxalase I reaction.
Citations
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Journal ArticleDOI
TL;DR: Examination of some of the aforementioned compounds has revealed that squaric acid does not function as an inhibitor of glyoxalase I and several other compounds are much less effective in this regard than previously reported.

8 citations

Journal ArticleDOI
TL;DR: The results indicate that D, and L-lactaldehyde are strong non-competitive inhibitors of glyoxalase I and the effect with the D-isomer is more pronounced, whereas both D,L-glyceraldehyde and acetaldehyde are moderately inhibitory and the nature of inhibition is strictly competitive.
Abstract: The possible effect of several physiologically important aldehydes has been tested on partially purified glyoxalase I of Ehrlich ascites carcinoma (EAC) cells. The results indicate that D, and L-lactaldehyde are strong non-competitive inhibitors of glyoxalase I and the effect with the D-isomer is more pronounced, whereas both D,L-glyceraldehyde and acetaldehyde are moderately inhibitory and the nature of inhibition is strictly competitive. Moreover, D,L-glyceraldehyde strongly inhibits the utilization of methylglyoxal by intact EAC cells. A search for the presence of several aldehyde metabolizing enzymes in EAC cells indicates that non-specific aldehyde reductase, methylglyoxal reductase, aldehyde dehydrogenase and alcohol dehydrogenase are apparently absent in this rapidly growing, highly de-differentiated malignant cell.

1 citations

References
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Journal ArticleDOI
TL;DR: An enzyme from goat plasma which catalyzes the oxidation of aminoacetone to methylglyoxal has been isolated and purified to apparent homogeneity and has been found to be identical with the well known amine oxidase.

46 citations


"A reinvestigation of inhibitors of ..." refers background or methods in this paper

  • ...We have been working with the various enzymes involved in the biosynthesis and breakdown of methylglyoxal (Ray and Ray, 1981, 1982a, 1983, 1984a, 1987)....

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  • ...The enzymes responsible for the formation of methylglyoxal have been purified from several sources (Hopper and Cooper, 1972; Ray and Ray, 1981, 1983, 1987; Murata et al., 1985)....

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Journal ArticleDOI
TL;DR: Two alpha-ketoaldehyde dehydrogenases, one catalyzing the oxidation of methylglyoxal to pyruvate with NAD and the other with NADP, were isolated from goat liver and happened to be co-purified.

44 citations


"A reinvestigation of inhibitors of ..." refers background or methods in this paper

  • ...We have been working with the various enzymes involved in the biosynthesis and breakdown of methylglyoxal (Ray and Ray, 1981, 1982a, 1983, 1984a, 1987)....

    [...]

  • ...We are also studying the metabolic control of these enzymes (Ray and Ray, 1982b, 1985)....

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Journal ArticleDOI
TL;DR: The inactivation by p-chloromercuribenzoate could be substantially protected by methylglyoxal in combination with NADH, indicating a possible involvement of one or more sulfhydryl group(s) at the active site of the enzyme.

43 citations


"A reinvestigation of inhibitors of ..." refers background or methods in this paper

  • ...The Ki’s for D- and L-lactaldehydes were calculated to be 0·46 mM and 1·67 mM, respectively (figure not presented)....

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  • ...Because L-lactaldehyde is formed from methylglyoxal in goat liver by the highly active methylglyoxal reductase (Ray and Ray, 1984a), the inhibition of glyoxalase I by L-lactaldehyde, although weak compared to that by the D-isomer, may have some physiological role to play in the regulation of…...

    [...]

  • ...Inhibition of yeast and goat liver glyoxalase I by D- and L-lactaldehydes It has been reported that lactaldehyde is a strong inhibitor of glyoxalase I (Ting et al., 1965)....

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  • ...Because L-lactaldehyde is formed from methylglyoxal in goat liver by the highly active methylglyoxal reductase (Ray and Ray, 1984a), the inhibition of glyoxalase I by L-lactaldehyde, although weak compared to that by the D-isomer, may have some physiological role to play in the regulation of methylglyoxal metabolism....

    [...]

  • ...When 1 mM methylglyoxal was used as substrate the goat liver enzyme was inhibited by 50% by 1 mM L-lactaldehyde, whereas the same degree of inhibition was obtained with only 0·02 mM D-lactaldehyde for the same concentration of methylglyoxal....

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Journal ArticleDOI
TL;DR: L-Threonine dehydrogenase, which forms aminoacetone from L-threonine and NAD, has been extensively purified from goat liver and a feedback inhibition of this enzyme has been observed with methylglyoxal.

42 citations


"A reinvestigation of inhibitors of ..." refers background in this paper

  • ...We are also studying the metabolic control of these enzymes (Ray and Ray, 1982b, 1985)....

    [...]

Book ChapterDOI
TL;DR: In this article, the authors discuss the assay method, purification procedure, and properties of methylglyoxal synthase and show that the most pure enzyme preparation (specific activity 530) shows one major and two minor protein bands 1° on acrylamide gel electrophoresis at pH 89 Neither dihydroxyacetone nor Da-glyceraldehyde 3-phosphate could substitute for dihydroxacetone phosphate in the reaction.
Abstract: Publisher Summary This chapter discusses the assay method, purification procedure, and properties of methylglyoxal synthase Methylglyoxal production can be measured continuously by coupling it to the lactoylglutathione lyase reaction and monitoring the formation of S -lactoylglutathione at 240 nm (Method 1); or discontinuously, at the end of the reaction period, by measurement of the bis-derivative formed on reaction with the 2,4-dinitrophenylhydrazine reagent (Method 2) The purification procedure of E coli and P saccharophila enzymes are also tabulated The enzyme in crude extracts loses little activity when stored at 0–4° over several days The most pure enzyme preparation (specific activity 530) shows one major and two minor protein bands 1° on acrylamide gel electrophoresis at pH 89 Neither dihydroxyacetone nor Da-glyceraldehyde 3-phosphate could substitute for dihydroxyacetone phosphate in the reaction The E coli and P saccharophila enzymes have molecular weights of approximately 67,000 as estimated by gel filtration Methylglyoxal synthase has been found in various Enterobacteriaceae and in certain Enterobacteriaceae-like organisms, such as Aeromonas formicans and Obesumbacterium proteus It has also been found in the strict anaerobes Clostridium pasteurianum and Clostridium tetanomorphum

42 citations


"A reinvestigation of inhibitors of ..." refers methods in this paper

  • ...Methylglyoxal was measured either by the 2,4-dinitrophenylhydrazine alkali colour reaction or by using the enzyme glyoxalase I and monitoring the formation of S-D-lactoylglutathione at 240 nm (Cooper, 1975)....

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  • ...In some cases the enzyme activity was measured by following the utilization of the substrate methylglyoxal; after the desired period of incubation the remaining methylglyoxal was estimated colorimetrically by the 2,4-dinitrophenylhydrazine alkali reaction (Cooper, 1975)....

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