The quaternary structure of ornithine transcarbamoylase and arginase from Saccharomyces cerevisiae.

Published

Journal Article (Academic article)

Electron microscopic studies employing negative staining, rotary shadowing, and unidirectional shadowing have revealed the subunit architecture of ornithine transcarbamoylase and arginase from Saccharomyces cerevisiae. These techniques have confirmed the quaternary structure of these enzymes, and have permitted an estimate of the shape and dimensions of each of the individual enzymes as well as those of the corresponding subunits to be determined. Both enzymes are trimers exhibiting 3-fold rotational symmetry with subunits which are oblate ellipsoids of revolution. The overall dimensions determined for ornithine transcarbamoylase are a height of 39 A and a width of 102 A. The consequent subunit dimensions are 59 X 59 X 39 A, yielding a subunit axial ratio of 1.51. Arginase has a height of 42 A and a width of 97 A. The subunit dimensions are 56 X 56 X 42 A, yielding a subunit axial ratio of 1.33. The hydrodynamic behavior of the two enzymes is fully consistent with this molecular architecture, suggesting that the structures proposed here are similar to those of the proteins in aqueous solution.

Duke Authors

Cited Authors

  • Duong, LT; Eisenstein, E; Green, SM; Ornberg, RL; Hensley, P

Published Date

  • September 1986

Published In

Volume / Issue

  • 261 / 27

Start / End Page

  • 12807 - 12813

International Standard Serial Number (ISSN)

  • 0021-9258

Conference Location

  • united states