5lzp

Structural highlights

Function

[PSA_MYCTU] Component of the proteasome core, a large protease complex with broad specificity involved in protein degradation. The M.tuberculosis proteasome is able to cleave oligopeptides not only after hydrophobic but also after basic, acidic and small neutral residues. Among the identified substrates of the M.tuberculosis proteasome are the pupylated FabD, PanB and Mpa proteins. One function of the proteasome is to contribute to M.tuberculosis ability to resist killing by host macrophages, since the core proteasome is essential for persistence of the pathogen during the chronic phase of infection in mice. The mechanism of protection against bactericidal chemistries of the host's immune response probably involves the degradation of proteins that are irreversibly oxidized, nitrated, or nitrosated.^{[1] [2]} [PSB_MYCTU] Component of the proteasome core, a large protease complex with broad specificity involved in protein degradation. The M.tuberculosis proteasome is able to cleave oligopeptides not only after hydrophobic but also after basic, acidic and small neutral residues. Among the identified substrates of the M.tuberculosis proteasome are the pupylated FabD, PanB and Mpa proteins. One function of the proteasome is to contribute to M.tuberculosis ability to resist killing by host macrophages, since the core proteasome is essential for persistence of the pathogen during the chronic phase of infection in mice. The mechanism of protection against bactericidal chemistries of the host's immune response probably involves the degradation of proteins that are irreversibly oxidized, nitrated, or nitrosated.^{[3] [4]} [BPA_MYCTU] Interacts with the core proteasome alpha-subunit (PrcA) through its C-terminal hydrophobic-tyrosine-X motif (HbYX motif). Interaction of Bpa with the proteasome stimulates proteosomal peptidase and casein degradation activity, which suggests Bpa could play a role in the removal of non-native or damaged proteins by influencing the conformation of the proteasome complex upon interaction. Can inhibit degradation of Pup-tagged substrates in vitro by competing with Mpa for association with the proteasome.^[5]

See Also

• Proteasome 3D structures

References

1. ↑ Lin G, Hu G, Tsu C, Kunes YZ, Li H, Dick L, Parsons T, Li P, Chen Z, Zwickl P, Weich N, Nathan C. Mycobacterium tuberculosis prcBA genes encode a gated proteasome with broad oligopeptide specificity. Mol Microbiol. 2006 Mar;59(5):1405-16. PMID:16468985 doi:http://dx.doi.org/10.1111/j.1365-2958.2005.05035.x
2. ↑ Gandotra S, Schnappinger D, Monteleone M, Hillen W, Ehrt S. In vivo gene silencing identifies the Mycobacterium tuberculosis proteasome as essential for the bacteria to persist in mice. Nat Med. 2007 Dec;13(12):1515-20. Epub 2007 Dec 2. PMID:18059281 doi:http://dx.doi.org/10.1038/nm1683
3. ↑ Lin G, Hu G, Tsu C, Kunes YZ, Li H, Dick L, Parsons T, Li P, Chen Z, Zwickl P, Weich N, Nathan C. Mycobacterium tuberculosis prcBA genes encode a gated proteasome with broad oligopeptide specificity. Mol Microbiol. 2006 Mar;59(5):1405-16. PMID:16468985 doi:http://dx.doi.org/10.1111/j.1365-2958.2005.05035.x
4. ↑ Gandotra S, Schnappinger D, Monteleone M, Hillen W, Ehrt S. In vivo gene silencing identifies the Mycobacterium tuberculosis proteasome as essential for the bacteria to persist in mice. Nat Med. 2007 Dec;13(12):1515-20. Epub 2007 Dec 2. PMID:18059281 doi:http://dx.doi.org/10.1038/nm1683
5. ↑ Delley CL, Laederach J, Ziemski M, Bolten M, Boehringer D, Weber-Ban E. Bacterial proteasome activator bpa (rv3780) is a novel ring-shaped interactor of the mycobacterial proteasome. PLoS One. 2014 Dec 3;9(12):e114348. doi: 10.1371/journal.pone.0114348., eCollection 2014. PMID:25469515 doi:http://dx.doi.org/10.1371/journal.pone.0114348
6. ↑ Bolten M, Delley CL, Leibundgut M, Boehringer D, Ban N, Weber-Ban E. Structural Analysis of the Bacterial Proteasome Activator Bpa in Complex with the 20S Proteasome. Structure. 2016 Dec 6;24(12):2138-2151. doi: 10.1016/j.str.2016.10.008. Epub 2016, Nov 10. PMID:27839949 doi:http://dx.doi.org/10.1016/j.str.2016.10.008