Microdetermination of d-amino acids and d-amino acid oxidase activity with 3-methyl-2-benzothiazolone hydrazone hydrochloride

SummaryEchis colorata bites cause impairment of platelet aggregation and hemostatic disorders. The mechanism by which the snake venom inhibits platelet aggregation was studied. Upon fractionation, aggregation impairment activity and L-amino acid oxidase activity were similarly separated from the crude venom, unlike other venom enzymes. Preparations of L-amino acid oxidase from E.colorata and from Crotalus adamanteus replaced effectively the crude E.colorata venom in impairment of platelet aggregation. Furthermore, different treatments known to inhibit L-amino acid oxidase reduced in parallel the oxidase activity and the impairment potency of both the venom and the enzyme preparation. H2O2 mimicked characteristically the impairment effects of L-amino acid oxidase and the venom. Catalase completely abolished the impairment effects of the enzyme and the venom. It is concluded that hydrogen peroxide formed by the venom L-amino acid oxidase plays a role in affecting platelet aggregation and thus could contribute to the extended bleeding typical to persons bitten by E.colorata.

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Biological role of D-amino acid oxidase and D-aspartate oxidase. Effects of D-amino acids.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)74201-x ◽

1993 ◽

Vol 268 (36) ◽

pp. 26941-26949

Author(s):

A D'Aniello ◽

G D'Onofrio ◽

M Pischetola ◽

G D'Aniello ◽

A Vetere ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Biological Role ◽

Acid Oxidase ◽

Amino Acid Oxidase

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The Effect of Castration and Testosterone Propionate on d-Amino Acid Oxidase Activity in the Mouse

Science ◽

10.1126/science.98.2534.89.a ◽

1943 ◽

Vol 98 (2534) ◽

pp. 89-89

Author(s):

L. C. Clark ◽

C. D. Kochakian ◽

R. Phyllis Fox

Keyword(s):

Amino Acid ◽

Oxidase Activity ◽

Testosterone Propionate ◽

Acid Oxidase ◽

Amino Acid Oxidase

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Localization of D-amino acid oxidase on the cell surface of human polymorphonuclear leukocytes

The Journal of Cell Biology ◽

10.1083/jcb.77.1.59 ◽

1978 ◽

Vol 77 (1) ◽

pp. 59-71 ◽

Cited By ~ 45

Author(s):

JM Robinson ◽

RT Briggs ◽

MJ Karnovsky

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Cell Surface ◽

Polymorphonuclear Leukocytes ◽

Ultrastructural Localization ◽

H2o2 Production ◽

Acid Oxidase ◽

Resting Cells ◽

Amino Acid Oxidase ◽

Human Polymorphonuclear Leukocytes

The ultrastructural localization of D-amino acid oxidase (DAO) was studied cytochemically by detecting sites of hydrogen peroxide production in human polymorphonuclear leukocytes (PMNs). Reaction product, which forms when cerous ions react with H2O2 to form an electron-dense precipitate, was demonstrated on the cell surface and within the phagosomes of phagocytically stimulated cells when D-amino acids were provided as substrate. Resting cells showed only slight activity. The competitive inhibitor D,L-2-hydroxybutyrate greatly reduced the D-amino acid-stimulated reaction while KCN did not. The cell surface reaction was abolished by nonpenetrating inhibitors of enzyme activity while that within the phagosome was not eliminated. Dense accumulations of reaction product were formed in cells which phagocytosed Staphylococcus aureus in the absence of exogenous substrate. No reaction product formed with Proteus vulgaris while an intermediate amount formed when Escherichia coli were phagocytosed. Variation in the amount of reaction product with the different bacteria correlated with the levels of D-amino acids in the bacterial cell walls which are available for the DAO of PMNs. An alternative approach utilizing ferricyanide as an electron acceptor was also used. This technique verified the results obtained with the cerium reaction, i.e., the DAO is located in the cell surface and is internalized during phagocytosis and is capable of H2O2 production within the phagosome. The present finding that DAO is localized on the cell surface further supports the concept that the plasma membrane is involved in peroxide formation in PMNs.

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Production ofD-amino acid oxidase byAspergillussp. strain O20 active on cephalosporin C

Canadian Journal of Microbiology ◽

10.1139/m97-040 ◽

1997 ◽

Vol 43 (3) ◽

pp. 292-295 ◽

Cited By ~ 2

Author(s):

Salim K. Mujawar ◽

Jaiprakash G. Shewale

Keyword(s):

Amino Acids ◽

Enzyme Activity ◽

Amino Acid ◽

Stationary Growth Phase ◽

Acid Oxidase ◽

Cephalosporin C ◽

Production Medium ◽

Stationary Growth ◽

Amino Acid Oxidase ◽

Aspergillus Sp

Aspergillus sp. strain O20 produces inducible D-amino acid oxidase intracellularly, only in the presence of some amino acids. The enzyme was induced most effectively by the addition of DL-alanine (1% w/v) to the production medium. Among the various compounds studied, production of the D-amino acid oxidase was enhanced by Aerosol-22, glucose, and sodium nitrate. D-Amino acid oxidase formation was observed during the onset of the stationary growth phase. Maximum enzyme activity was recorded after 96 h of fermentation (1000 IU/L).Key words: D-amino acid oxidase, Aspergillus sp., 7-aminocephalosporanic acid, cephalosporin C.

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An Automated Detection System for Most L-α-Amino Acids

Clinical Chemistry ◽

10.1093/clinchem/15.2.154 ◽

1969 ◽

Vol 15 (2) ◽

pp. 154-161 ◽

Cited By ~ 6

Author(s):

K Van Dyke ◽

C Szustkiewicz

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Detection System ◽

Automated System ◽

Acid Oxidase ◽

Enzymatic Reactions ◽

Amino Acid Oxidase ◽

Automated Method ◽

Wide Range

Abstract An automated system for the determination of the L-α form of the majority of amino acids is presented. The method is based upon oxidative deamination of the amino acid coupled with oxidation of o-dianisidine by hydrogen peroxide. This procedure can be used comparatively for the determination of a mixture of L-α-amino acids or for the majority of separated L-α-amino acids (especially in conjunction with column separations from urine and blood which give falsely positive identification with ninhydrin detection). The stereospecific nature of the L-α-amino acid oxidase enables the investigator to quantitate the amount of L-α-amino acid in the presence of the D-α form. From an academic viewpoint, the extreme sensitivity and wide range of the detection system make it advantageous for the study of the enzyme itself. This automated method also may be employed to follow enzymatic reactions—e.g., those catalyzed by peptidases or racemases. The methodology is extremely convenient with good reagent stability and is much more sensitive than manometric technics.

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