FEATURES

FAMILY

DESCRIPTION

Also known as ARC_MYCTU, mpa. ATPase which is responsible for recognizing, binding, unfolding and translocation of pupylated proteins into the bacterial 20S proteasome core particle. May be essential for opening the gate of the 20S proteasome via an interaction with its C-terminus, thereby allowing substrate entry and access to the site of proteolysis. Thus, the C-termini of the proteasomal ATPase may function like a 'key in a lock' to induce gate opening and therefore regulate proteolysis. Is required but not sufficient to confer resistance against the lethal effects of reactive nitrogen intermediates (RNI), antimicrobial molecules produced by activated macrophages and other cell types. Homohexamer. Assembles into a hexameric ring structure that caps the 20S proteasome core. Strongly interacts with the prokaryotic ubiquitin-like protein Pup through a hydrophobic interface; the interacting region of Mpa lies in its N-terminal coiled-coil domain. There is one Pup binding site per Mpa hexamer ring; the K(D) measured is about 3.8 uM. Upon ATP-binding, the C-terminus of Mpa interacts with the alpha-rings of the proteasome core, possibly by binding to the intersubunit pockets.

EXTERNAL LINKS

mpa

Mutations

Mutation(s) distribution

Mutations table