Posttranslational modification of the 20S proteasomal proteins of the archaeon Haloferax volcanii.

ABSTRACT: 20S proteasomes are large, multicatalytic proteases that play an important role in intracellular protein degradation. The barrel-like architecture of 20S proteasomes, formed by the stacking of four heptameric protein rings, is highly conserved from archaea to eukaryotes. The outer two rings are composed of alpha-type subunits, and the inner two rings are composed of beta-type subunits. The halophilic archaeon Haloferax volcanii synthesizes two different alpha-type proteins, alpha1 and alpha2, and one beta-type protein that assemble into at least two 20S proteasome subtypes. In this study, we demonstrate that all three of these 20S proteasomal proteins (alpha1, alpha2, and beta) are modified either post- or cotranslationally. Using electrospray ionization quadrupole time-of-flight mass spec

SUBMITTER: Humbard MA 

PROVIDER: S-EPMC1636277 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature