Corpus ID: 20802250

Purification and characterization of human kidney cytosolic cysteine conjugate beta-lyase activity.

  title={Purification and characterization of human kidney cytosolic cysteine conjugate beta-lyase activity.},
  author={Lawrence H. Lash and Rita M. Nelson and R A Van dyke and M W Anders},
  journal={Drug metabolism and disposition: the biological fate of chemicals},
  volume={18 1},
  • L. Lash, R. Nelson, +1 author M. W. Anders
  • Published 1990
  • Chemistry, Medicine
  • Drug metabolism and disposition: the biological fate of chemicals
The central role of cysteine conjugate beta-lyase (beta-lyase) in the bioactivation of nephrotoxic halogenated hydrocarbons and the possibility of human exposure to these chemicals has focused interest on the beta-lyase from human kidney. Human kidney tissue was collected as surgical waste material, and subcellular fractions were isolated by differential centrifugation. Human beta-lyase activity, determined with S-(2-benzothiazolyl)-L-cysteine (BTC) as the substrate, was present in the… Expand
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It is demonstrated that most selenocysteine Se-conjugates are beta-eliminated at a very high activity by purified beta-lyase/GTK, implicating an important role of this protein in the previously reported beta-Elimination reactions in rat renal cytosol. Expand
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Cysteine Conjugate Toxicity in a Human Cell Line: Correlation with C-S Lyase Activity in Human Hepatic Tissue
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High Activities of Glutamine Transaminase K (Dichlorovinylcysteine β‐Lyase) and ω‐Amidase in the Choroid Plexus of Rat Brain
It is shown that with dichlorovinylcysteine as substrate the only detectable cysteine‐S‐conjugate β‐lyase in rat brain homogenates is identical to glutamine transaminase K, and that any explanation of the neurotoxicity of halogenated xenobiotics must take into account the role of glutamines transaminases K and its presence in the choroid plexus. Expand
Role of the renal cysteine conjugate beta-lyase pathway in inhaled compound A nephrotoxicity in rats.
Nephrotoxicity of inhaled compound A in rats was associated with renal uptake of compound A S-conjugates and cysteine conjugates metabolism by renal beta-lyase, and route of administration does not apparently influence nephrotoxicity. Expand
Evaluation of the kinetics of beta-elimination reactions of selenocysteine Se-conjugates in human renal cytosol: possible implications for the use as kidney selective prodrugs.
The hypothesis that selenocysteine Se-conjugates may be useful as prodrugs to target pharmacologically active selenol compounds (e.g., antitumor or chemoprotective) to the kidney in humans is supported. Expand
Human mitochondrial and cytosolic branched-chain aminotransferases are cysteine S-conjugate beta-lyases, but turnover leads to inactivation.
The present results suggest that BCAT isozymes may contribute to the mitochondrial toxicity of these compounds by providing thioacylating fragments, but inactivation of the BCATIsozymes might also block essential metabolic pathways. Expand
Cysteine conjugate beta-lyase activity of rat erythrocytes and formation of beta-lyase-derived globin monoadducts and cross-links after in vitro exposure of erythrocytes to S-(1,2-dichlorovinyl)-L-cysteine.
The results suggested that erythrocytes have beta-lyase but not S-oxidase activity, and further support for this hypothesis was obtained using S-(2-benzothiazolyl)-L-cysteine, an alternative substrate forbeta-lyases. Expand
Enzymology of Cysteine S-Conjugote β-Lyases
Publisher Summary This chapter addresses recent findings concerning the identity of the cysteine S-conjugate β-lyases in mammals, the reactions catalyzed by these enzymes, and the pharmacologicalExpand