The mycobacterial Mpa-proteasome unfolds and degrades pupylated substrates by engaging Pup's N-terminus.

ABSTRACT: Mycobacterium tuberculosis, along with other actinobacteria, harbours proteasomes in addition to members of the general bacterial repertoire of degradation complexes. In analogy to ubiquitination in eukaryotes, substrates are tagged for proteasomal degradation with prokaryotic ubiquitin-like protein (Pup) that is recognized by the N-terminal coiled-coil domain of the ATPase Mpa (also called ARC). Here, we reconstitute the entire mycobacterial proteasome degradation system for pupylated substrates and establish its mechanistic features with respect to substrate recruitment, unfolding and degradation. We show that the Mpa-proteasome complex unfolds and degrades Pup-tagged proteins and that this activity requires physical interaction of the ATPase with the proteasome. Furthermore, we establis

SUBMITTER: Striebel F 

PROVIDER: S-EPMC2857465 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature