| Structural highlights
Function
[RIPA_MYCTU] Peptidoglycan endopeptidase that cleaves the bond between D-glutamate and meso-diaminopimelate. Binds and degrades high-molecular weight peptidoglycan from a number of Actinobacteria; activity is increased in the presence of RpfB and inhibited by PBP1A (ponA1). Required for normal separation of daughter cells after cell division and for cell wall integrity. Required for host cell invasion and intracellular survival in host macrophages.[1] [2] [3] [4] [5]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Cell separation depends on cell-wall hydrolases that cleave the peptidoglycan layer connecting daughter cells. In Mycobacterium tuberculosis, this process is governed by the predicted endopeptidase RipA. In the absence of this enzyme, the bacterium is unable to divide and exhibits an abnormal phenotype. We here report the crystal structure of a relevant portion of RipA, containing its catalytic-domain and an extra-domain of hitherto unknown function. The structure clearly demonstrates that RipA is produced as a zymogen, which needs to be activated to achieve cell-division. Bacterial cell-wall degradation assays and proteolysis experiments strongly suggest that activation occurs via proteolytic processing of a fully solvent exposed loop identified in the crystal structure. Indeed, proteolytic cleavage at this loop produces an activated form, consisting of the sole catalytic domain. Our work provides the first evidence of self-inhibition in cell-disconnecting enzymes and opens a field for the design of novel antitubercular therapeutics.
Structure and functional regulation of RipA, a mycobacterial enzyme essential for daughter cell separation.,Ruggiero A, Marasco D, Squeglia F, Soldini S, Pedone E, Pedone C, Berisio R Structure. 2010 Sep 8;18(9):1184-90. PMID:20826344[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Gao LY, Pak M, Kish R, Kajihara K, Brown EJ. A mycobacterial operon essential for virulence in vivo and invasion and intracellular persistence in macrophages. Infect Immun. 2006 Mar;74(3):1757-67. PMID:16495549 doi:10.1128/IAI.74.3.1757-1767.2006
- ↑ Hett EC, Chao MC, Steyn AJ, Fortune SM, Deng LL, Rubin EJ. A partner for the resuscitation-promoting factors of Mycobacterium tuberculosis. Mol Microbiol. 2007 Nov;66(3):658-68. Epub 2007 Oct 4. PMID:17919286 doi:10.1111/j.1365-2958.2007.05945.x
- ↑ Hett EC, Chao MC, Deng LL, Rubin EJ. A mycobacterial enzyme essential for cell division synergizes with resuscitation-promoting factor. PLoS Pathog. 2008 Feb 29;4(2):e1000001. doi: 10.1371/journal.ppat.1000001. PMID:18463693 doi:10.1371/journal.ppat.1000001
- ↑ Ruggiero A, Marasco D, Squeglia F, Soldini S, Pedone E, Pedone C, Berisio R. Structure and functional regulation of RipA, a mycobacterial enzyme essential for daughter cell separation. Structure. 2010 Sep 8;18(9):1184-90. PMID:20826344 doi:10.1016/j.str.2010.06.007
- ↑ Both D, Schneider G, Schnell R. Peptidoglycan Remodeling in Mycobacterium tuberculosis: Comparison of Structures and Catalytic Activities of RipA and RipB. J Mol Biol. 2011 Oct 14;413(1):247-60. Epub 2011 Aug 16. PMID:21864539 doi:10.1016/j.jmb.2011.08.014
- ↑ Ruggiero A, Marasco D, Squeglia F, Soldini S, Pedone E, Pedone C, Berisio R. Structure and functional regulation of RipA, a mycobacterial enzyme essential for daughter cell separation. Structure. 2010 Sep 8;18(9):1184-90. PMID:20826344 doi:10.1016/j.str.2010.06.007
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