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Metabolisme du γ-aminobutyrate chez Agaricus bisporus Lge.

II. La γ-aminobutyrate: α-cetoglutarate aminotransferase

Metabolism of γ-aminobutyrate in Agaricus bisporus Lge.

II: γ-aminobutyrate: γ-ketoglutarate aminotransferase

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Summary

Transamination between γ-aminobutyrate and α-ketoglutarate provides a pathway for the utilization of γ-aminobutyrate in fruit-bodies of Agaricus bisporus Lge. This reaction leads to the formation of succinic semialdehyde, a metabolic intermediate in the metabolism of γ-aminobutyrate to succinate in the cell. γ-aminobutyrate: α-ketoglutarate aminotransferase (E.C. 2.6.1.19) was sonically extracted from the mitochondrial fraction and partially purified by DEAE-cellulose column chromatography. Aminotransferase had a pH optimum between 8.1 and 8.5 and did not require pyridoxal-phosphate in vitro; however, the enzyme was inhibited by carbonyl-trapping reagents such as pyridoxal-phosphate activated enzymes. The Km values for γ-aminobutyrate and α-ketoglutarate calculated from Lineweaver-Burk plots were 2.2×10-4 M and 2.5×10-3 M, respectively. The transaminase was specific for α-ketoglutarate but not for γ-aminobutyrate; aspartate, α-alanine and δ-aminovalerianate also functioned as amino-group donors. Activity of the enzyme was not influenced by the addition of carboxylic acids of the Krebs cycle. The reversal of the transamination reaction showed optimal rates at pH 9.0–9.3. Some considerations on the physiological significance of these results are given.

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Abbreviations

DEAE:

diéthylaminoéthyl

EDTA:

éthylène diamine tétraacétate

DCIP:

2,6-dichlorophénol-indophénol

GABA:

acide γ-aminobutyrique

GABA-T:

γ-aminobutyrate: α-cétoglutarate aminotransférase

GAD:

L-glutamate décarboxylase

Glu:

acide glutamique

α-KG:

α-cétoglutarate

MBTH:

3-méthyl-2-benzothiazolinone hydrazone

PLP:

pyridoxal-5′-phosphate

PMS:

phénazine méthosulfate

SSA:

acide semialdéhyde succinique

TCA:

acide trichloracétique

Tris:

2-amino-2-(hydroxyméthyl)-1,3-propanediol

Références

  • Baldy, P., Latché, J.C.: Etude du métabolisme de l'acide γ-aminobutyrique dans les carpophores d'Agaricus bisporus Lge: incorporation d'acide γ-aminobutyrique 1-14C. C.R. Acad. Sci. (Paris) Sér. D. 275, 2123–2126 (1972)

    Google Scholar 

  • Baldy, P.: Métabolisme de l'acide γ-aminobutyrique dans les carpophores d'Agaricus bisporus Lge. Etude préliminaire de la γ-aminobutyrate: α-cétoglutarate aminotransférase et de la semialdéhyde succinate: NAD(P) oxydoréductase. C.R. Acad. Sci. (Paris) Sér. D. 275, 2877–2880 (1972)

    Google Scholar 

  • Baldy, P.: Métabolisme du γ-aminobutyrate chez Agaricus bisporus. I. La L-glutamate-1-carboxy-lyase. Physiol. Plant. 34, 365–372 (1975)

    Google Scholar 

  • Baldy, P., Latché, J.C.: Quelques aspects de la biosynthèse et de l'utilisation de l'acide γ-aminobutyrique, possible source d'azote pour Agaricus bisporus Lge. Mushroom Science. IX (sous presse)

  • Bloch-Tardy, M., Rolland, B., Gonnard, P.: Pig brain 4-aminobutyrate 2-Keto glutarate transaminase. Purification, kinetics and physical properties. Biochimie 56, 823–832 (1974)

    PubMed  Google Scholar 

  • Bruce, R., Sims, K., Pitts, Jr., F.N.: Synthesis and purification of succinic semialdehyde. Analyt. Biochem. 41, 271–273 (1971)

    PubMed  Google Scholar 

  • Dixon, R.O.D., Fowden, L.: γ-aminobutyric acid metabolism in plants. Part 2. Metabolism in higher plants. Ann. Bot. 25, 513–530 (1961)

    Google Scholar 

  • Forest, J.C., Wightman, F.: Amino acid metabolism in plants. III. Purification and some properties of a multispecific aminotransferase isolated from bushbean seedlings (Phaseolus vulgaris L.). Canad. J. Biochem. 50, 813–829 (1972)

    Google Scholar 

  • Gadal, P.: Sur le métabolisme du chêne et de ses zoocécidies. Etude particulière de la biosynthèse des acides aminés aromatiques. Thèse Doct. Sci. Nat. Toulouse (1970)

  • Gallinet, J.P.: Les mitochondries des champignons supérieurs: composition de la chaîne respiratoire des mitochondries d'Agaricus campestris (F.) var. bisporus. C.R. Acad Sci. (Paris) Sér. D. 277, 2693–2696 (1973)

    Google Scholar 

  • Hall, Z.W., Kravitz, E.A.: The metabolism of γ-aminobutyric acid (GABA) in the lobster nervous system. I. GABA-glutamate transaminase. J. Neurochem. 14, 45–54 (1967)

    PubMed  Google Scholar 

  • Kammeraat, C., Veldstra, H.: Characterization of succinate semialdehyde dehydrogenase from rat brain. Biochim. Biophys. Acta 151, 1–10 (1968)

    PubMed  Google Scholar 

  • King, T.E.: Reconstitution of respiratory enzyme systems. XI. Use of artificial electron acceptors in the assay of succinate-dehydrogenating enzymes. J. Biol. Chem. 238, 4032–4036 (1963)

    PubMed  Google Scholar 

  • Lang, C.A.: Simple microdetermination of Kjeldahl nitrogen in biological materials. Analyt. Chem. 30, 1692–1694 (1958)

    Google Scholar 

  • Latché, J.C.: Quelques aspects du métabolisme azoté du carpophore d'Agaricus bisporus Lge. Etude en fonction du phénomène des volées. Thèse Doct. Sci. Nat. Toulouse (1970)

  • O'Leary, M.H.: Coenzyme analog inhibitors of apoglutamate decarboxylase. Biochem. 8, 1117–1122 (1969)

    Google Scholar 

  • Lowry, O.H.: Rosebrough, N.J., Farr, A.L., Randall, R.J.: Protein measurement with the Folin phenol reagent. J. biol. Chem. 193, 265–275 (1951)

    PubMed  Google Scholar 

  • Paz, M.A., Blumenfeld, O.O., Rojkind, M., Henson, E., Furfine, C., Gallop, P.M.: Determination of carbonyl compounds with N-methyl benzothiazolone Hydrazone. Arch. Biochem. Biophys. 109, 548–559 (1965)

    PubMed  Google Scholar 

  • Piquemal, M.: Sur le métabolisme de l'acide glutamique source d'azote et de carbone pour le mycelium d'Agaricus bisporus. Thèse Doct. Spécialité (Physiologie Végétale), Toulouse (1970)

  • Prescott, B.A., Waelsch, H.: A microdetermination of glutamic acid and its application to protein analysis. J. biol. Chem. 164, 331–343 (1946)

    Google Scholar 

  • Sanchez-Medina, F., Mayor, F.: L-glutamate-1-carboxy-lyase and 4-aminobutyrate: 2-oxoglutarate aminotransferase in succulent plants. Rev. esp. Fisiol. 26, 217–224 (1970)

    PubMed  Google Scholar 

  • Sawicki, E., Hauser, T.R., Stanley, T.W., Elbert, W.: The 3-methyl-2-benzothiazolone hydrazone test. Sensitive new methods for the detection, rapid estimation, and determination of aliphatic aldehydes. Analyt. Chem. 33, 93–96 (1961)

    Google Scholar 

  • Scott, F.M., Jakoby, W.B.: Soluble γ-aminobutyric-glutamic transaminase from Pseudomonas fluorescens. J. biol. Chem. 234, 932–936 (1959)

    PubMed  Google Scholar 

  • Streeter, J.G., Thompson, J.F.: In vivo and in vitro studies on γ-aminobutyric metabolism with the radish plant (Raphanus sativus L.). Plant. Physiol. 49, 579–584 (1972)

    Google Scholar 

  • Sytinsky, I.A., Vasilijev, V.Y.: Some catalytic properties of purified γ-aminobutyrate-α-oxoglutarate transaminase from the rat brain. Enzymologia 39, 1–11 (1970)

    PubMed  Google Scholar 

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Baldy, P. Metabolisme du γ-aminobutyrate chez Agaricus bisporus Lge.. Planta 130, 275–281 (1976). https://doi.org/10.1007/BF00387833

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