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A. L. Green

Bio: A. L. Green is an academic researcher from Salisbury University. The author has contributed to research in topics: Monoamine oxidase & Chymotrypsin. The author has an hindex of 2, co-authored 2 publications receiving 147 citations.

Papers
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Journal ArticleDOI
TL;DR: Michael, S. E. & Charlwood, P. A. (1958).
Abstract: Michael, S. E. (1958). Ab8tr. Comm. 4thint,. Congr. Biochem., Vienna, no. 2-106, p. 28. Pedersen, K. 0. (1958). J. phys. Chem. 62, 1282. Popjaik, G. & McCarthy, E. F. (1946). Biochem. J. 40, 789. Ram, J. S. & Maurer, P. H. (1958). Arch. Biochem. Biophys. 76, 28. Reichmann, M. E. & Charlwood, P. A. (1954). Canad. J. Chem. 32, 1092. Schwert, G. W. (1957). J. Amer. chem. Soc. 79, 139. Smith, D. B., Wood, G. C. & Charlwood, P. A. (1956). Canad. J. Chem. 34, 364. Svedberg, T. & Pedersen, K. 0. (1940). The Ultracentrifuge. Oxford University Press. Warren, R. L. & Charlwood, P. A. (1953). Nature, Lond., 171, 353. Wieme, R. J. (1959). Clin. chim. Acta, 4, 317. Williams, J. W., van Holde, K. E., Baldwin, R. L. & Fujita, H. (1958). Chem. Rev. 58, 715.

142 citations

Journal ArticleDOI
TL;DR: The present paper describes the complete reactivation of phosphorylated chymotrypsin by oximes and hydroxamic acids and necessitate some modification of views on the mechanisms for chymOTryptic hydrolysis which have been proposed recently.
Abstract: Chymotrypsin, like most other enzymes with esterase activity, is inactivated by combination with organophosphates (Balls & Jansen, 1952). The inactive phosphorylated enzyme is relatively stable in water but hydroxylamine and picolinohydroxamic acid will restore the activity by nucleophilic displacement of the enzyme from the phosphoryl residue (Cunningham, 1954; Jandorf, Crowell & Levin, 1955). The only reported kinetic study of this process is by Cunningham (1954) on reactivation with hydroxylamine, but his conclusions as to mechanism are open to criticism as, at best, only about 30% of the original enzymic activity could be recovered. The present paper describes the complete reactivation of phosphorylated chymotrypsin by oximes and hydroxamic acids. The results necessitate some modification of views on the mechanisms for chymotryptic hydrolysis which have been proposed recently (Cunningham, 1957; Dixon & Neurath, 1957a; Davies & Green, 1958).

18 citations


Cited by
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Journal ArticleDOI
TL;DR: The present investigation was undertaken to develop methods for preparation of banana polyphenoloxidase (PPO)3 and to determine some of its properties in comparison with phenol oxidases from other sources.
Abstract: Griffiths (13) has presented evidence indicating that the browning reactions of banana fruit result from the enzymic oxidation of dopamine (3,4 dihydroxyphenylethyliamine) by polyphenoloxidase. Although dopamine does occur in various fruits and vegetables (23), it has not previously been implicated as an important substrate in browning reactions. The present investigation was undertaken to develop methods for preparation of banana polyphenoloxidase (PPO)3 and to determine some of its properties in comparison with phenol oxidases from other sources.

171 citations

Journal ArticleDOI
R F Pratt1
17 Nov 1989-Science
TL;DR: A phosphonate monoester, m-carboxyphenyl phenylacetamidomethylphosphonate, has been found to be a specific inhibitor of the class C beta-lactamase of Enterobacter cloacae P99, suggesting that the loss of enzyme activity is due to phosphonylation of an active site functional group.
Abstract: A phosphonate monoester, m-carboxyphenyl phenylacetamidomethylphosphonate, has been found to be a specific inhibitor of the class C beta-lactamase of Enterobacter cloacae P99. Inactivation is rapid (10(3) per second per molar concentration) and reactivation very slow (2.2 X 10(-6) per second). Apparently concerted with the inactivation, one equivalent (with respect to the enzyme) of m-hydroxybenzoate is released. Reactivation is accelerated by hydroxylamine and benzohydroxamate. This suggests that the loss of enzyme activity is due to phosphonylation of an active site functional group. This discovery holds the promise of a new general class of beta-lactamase inhibitors and, perhaps, antibiotics.

122 citations

Journal ArticleDOI
TL;DR: Kinetic parameters of liver and brain monoamine oxidase with various substrates and inhibitors appeared to be the same when determined by either colorimetric or radiometric methods.

110 citations

Journal ArticleDOI
TL;DR: The inhibitor of γ‐aminobutyrate transaminase (GABA‐T), amino‐oxyacetic acid (AOAA), drastically reduced the activity of GABA‐T to 30 per cent of the control value, with a corresponding increase of brain GABA, but had no effect on theActivity of glutamate decarboxylase (GAD).
Abstract: — (1) The inhibitor of γ-aminobutyrate transaminase (GABA-T), amino-oxyacetic acid (AOAA), drastically reduced the activity of GABA-T to 30 per cent of the control value, with a corresponding increase of brain GABA, but had no effect on the activity of glutamate decarboxylase (GAD) (2) The monoamine oxidase (MAO) inhibitors phenelzine, phenylpropylhydrazine and phenylvalerylhydrazine, lowered GABA-T activity to 58, 49 and 48 per cent, respectively; this was associated with a marked elevation of brain GABA (3) The action of phenelzine and phenylpropylhydrazine in vivo and in vitro could be abolished by pre-treatment of the tissue with the structurally related MAO inhibitors phenylisopropylhydrazine and trans-2-phenylcyclopropylamine These had no action on the GABA system in vivo, either on the GABA content or on the GABA-T activity These latter drugs, however, were unable to influence the effects of AOAA either on GABA or on GABA-T (4) The possible mechanism of action on GABA and the enzyme activities of the GABA system is discussed

87 citations

Journal ArticleDOI
TL;DR: The data suggest that Pb‐exposure perturbs the aminergic system in the cerebral cortex, cerebellum and hippocampus and may contribute to the cognitive and behavioural impairments observed in P b‐exposed rats.

85 citations