Protein
Pup--protein ligase
Organism
Mycobacterium tuberculosis (strain CDC 1551 / Oshkosh)
Function
Catalyzes the covalent attachment of the prokaryotic ubiquitin-like protein modifier Pup to the proteasomal substrate proteins, thereby targeting them for proteasomal degradation. This tagging system is termed pupylation. The ligation reaction involves the side-chain carboxylate of the C-terminal glutamate of Pup and the side-chain amino group of a substrate lysine. PafA is required to confer resistance against the lethal effects of reactive nitrogen intermediates (RNI), antimicrobial molecules produced by activated macrophages and other cell types.
Similarity
Belongs to the Pup ligase/Pup deamidase family. Pup-conjugating enzyme subfamily.
Sequence
MQRRIMGIETEFGVTCTFHGHRRLSPDEVARYLFRRVVSWGRSSNVFLRNGARLYLDVGSHPEYATAECDSLVQLVTHDRAGEWVLEDLLVDAEQRLADEGIGGDIYLFKNNTDSAGNSYGCHENYLIVRAGEFSRISDVLLPFLVTRQLICGAGKVLQTPKAATYCLSQRAEHIWEGVSSATTRSRPIINTRDEPHADAEKYRRLHVIVGDSNMSETTTMLKVGTAALVLEMIESGVAFRDFSLDNPIRAIREVSHDVTGRRPVRLAGGRQASALDIQREYYTRAVEHLQTREPNAQIEQVVDLWGRQLDAVESQDFAKVDTEIDWVIKRKLFQRYQDRYDMELSHPKIAQLDLAYHDIKRGRGIFDLLQRKGLAARVTTDEEIAEAVDQPPQTTRARLRGEFISAAQEAGRDFTVDWVHLKLNDQAQRTVLCKDPFRAVDERVKRLIASM