Insights into subunit interactions in the heterotetrameric structure of potato ADP-glucose pyrophosphorylase.

ABSTRACT: ADP-glucose pyrophosphorylase, a key allosteric enzyme involved in higher plant starch biosynthesis, is composed of pairs of large (LS) and small subunits (SS). Current evidence indicates that the two subunit types play distinct roles in enzyme function. The LS is involved in mainly allosteric regulation through its interaction with the catalytic SS. Recently the crystal structure of the SS homotetramer has been solved, but no crystal structure of the native heterotetrameric enzyme is currently available. In this study, we first modeled the three-dimensional structure of the LS to construct the heterotetrameric enzyme. Because the enzyme has a 2-fold symmetry, six different dimeric (either up-down or side-by-side) interactions were possible. Molecular dynamics simulations were carried out

SUBMITTER: Tuncel A 

PROVIDER: S-EPMC2553129 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature