Purification and biochemical characterization of gamma-glutamylcysteine synthetase from a human malignant astrocytoma cell line.

Journal Article

gamma-Glutamylcysteine synthetase (EC 6.3.2.2.) the key regulatory enzyme in glutathione biosynthesis was purified from a human malignant astrocytoma cell line using a combination of ammonium sulfate fractionation, DE-52 cellulose chromatography and ATP-agarose affinity chromatography. The purified protein had a specific activity of 1725 units/mg protein, which represented an 86-fold purification and a 22% yield. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed two major subunits with apparent molecular sizes of 72 kDa and 32 kDa. The Km values for L-glutamate and L-alpha-aminobutyrate were 0.03 mM and 0.14 mM respectively. These molecular and catalytic properties of gamma-glutamylcysteine synthetase from astrocytoma cell line are similar, but not identical to those purified from rat kidney.

Full Text

Duke Authors

Cited Authors

  • Sriram, R; Ali-Osman, F

Published Date

  • August 1993

Published In

Volume / Issue

  • 30 / 6

Start / End Page

  • 1053 - 1060

PubMed ID

  • 8106072

International Standard Serial Number (ISSN)

  • 1039-9712

Language

  • eng

Conference Location

  • England