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5uct

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Revision as of 12:32, 23 September 2020

Mycobacterium tuberculosis toxin MazF-mt6

Structural highlights

5uct is a 2 chain structure with sequence from Myctu. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Gene:	mazF3, mazF-mt6, Rv1102c (MYCTU)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[MAZF3_MYCTU] Toxic component of a type II toxin-antitoxin (TA) module. Acts as an mRNA and 23S rRNA interferase, cleaving predominantly after the first 2 Us in the sequence 5'-UUCCU-3'; in 23S rRNA only cleaves once in the ribosomal A site in dissociated but not intact ribosomes. Cleavage of 23S rRNA inhibits protein translation; the 23S rRNA region cleaved is involved in tRNA-binding in the A site, 30S and 50S subunit interaction and ribosome recycling factor association (PubMed:23650345). Upon expression in E.coli and M.smegmatis inhibits cell growth and colony formation. It dramatically increases persister cell formation in M.smegmatis upon challenge with gentamicin or kanamycin. Overexpression leads to bacteriostasis rather than bacteriocide. Its toxic effect is neutralized by coexpression with cognate antitoxin MazE3.^[1] ^[2] ^[3] ^[4] ^[5] ^[6]

Publication Abstract from PubMed

Toxin-antitoxin systems are ubiquitous in prokaryotic and archaea genomes and regulate growth in response to stress. E. coli contains at least 36 putative toxin-antitoxin gene pairs, and some pathogens such as Mycobacterium tuberculosis (Mtb) have over 90 toxin-antitoxin operons. E. coli MazF cleaves free mRNA after encountering stress and nine Mtb MazF family members cleave mRNA, tRNA, or rRNA. Moreover, Mtb MazF-mt6 cleaves 23S rRNA Helix 70 to inhibit protein synthesis. The overall tertiary folds of these MazFs are predicted to be similar, therefore it is unclear how they recognize structurally distinct RNAs. Here we report the 2.7 A X-ray crystal structure of MazF-mt6. MazF-mt6 adopts a PemK-like fold, but lacks an elongated beta1-beta2 linker, a region that typically acts as a gate to direct RNA or antitoxin binding. In the absence of an elongated beta1-beta2 linker, MazF-mt6 is unable to transition between open and closed states, suggesting that the regulation of RNA or antitoxin selection may be distinct from that in canonical MazFs. Additionally, a shortened beta1-beta2 linker allows for the formation of a deep, solvent accessible, active-site pocket which may allow recognition of specific, structured RNAs like H70. Structure-based mutagenesis and bacterial growth experiments demonstrate that MazF-mt6 residues Arg-13, Asp-10, and Thr-36 are critical for RNase activity and likely catalyze the proton-relay mechanism for RNA cleavage. These results provide further critical insights into how MazF secondary structural elements adapt to recognize diverse RNA substrates.

The structure and function of Mycobacterium tuberculosis MazF-mt6 provides insights into conserved features of MazF endonucleases.,Hoffer ED, Miles SJ, Dunham CM J Biol Chem. 2017 Mar 15. pii: jbc.M117.779306. doi: 10.1074/jbc.M117.779306. PMID:28298445^[7]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Zhu L, Zhang Y, Teh JS, Zhang J, Connell N, Rubin H, Inouye M. Characterization of mRNA interferases from Mycobacterium tuberculosis. J Biol Chem. 2006 Jul 7;281(27):18638-43. Epub 2006 Apr 12. PMID:16611633 doi:http://dx.doi.org/10.1074/jbc.M512693200
↑ Gupta A. Killing activity and rescue function of genome-wide toxin-antitoxin loci of Mycobacterium tuberculosis. FEMS Microbiol Lett. 2009 Jan;290(1):45-53. doi:, 10.1111/j.1574-6968.2008.01400.x. Epub 2008 Nov 10. PMID:19016878 doi:http://dx.doi.org/10.1111/j.1574-6968.2008.01400.x
↑ Ramage HR, Connolly LE, Cox JS. Comprehensive functional analysis of Mycobacterium tuberculosis toxin-antitoxin systems: implications for pathogenesis, stress responses, and evolution. PLoS Genet. 2009 Dec;5(12):e1000767. doi: 10.1371/journal.pgen.1000767. Epub 2009, Dec 11. PMID:20011113 doi:http://dx.doi.org/10.1371/journal.pgen.1000767
↑ Han JS, Lee JJ, Anandan T, Zeng M, Sripathi S, Jahng WJ, Lee SH, Suh JW, Kang CM. Characterization of a chromosomal toxin-antitoxin, Rv1102c-Rv1103c system in Mycobacterium tuberculosis. Biochem Biophys Res Commun. 2010 Sep 24;400(3):293-8. doi:, 10.1016/j.bbrc.2010.08.023. Epub 2010 Aug 10. PMID:20705052 doi:http://dx.doi.org/10.1016/j.bbrc.2010.08.023
↑ Schifano JM, Edifor R, Sharp JD, Ouyang M, Konkimalla A, Husson RN, Woychik NA. Mycobacterial toxin MazF-mt6 inhibits translation through cleavage of 23S rRNA at the ribosomal A site. Proc Natl Acad Sci U S A. 2013 May 21;110(21):8501-6. doi:, 10.1073/pnas.1222031110. Epub 2013 May 6. PMID:23650345 doi:http://dx.doi.org/10.1073/pnas.1222031110
↑ Tiwari P, Arora G, Singh M, Kidwai S, Narayan OP, Singh R. MazF ribonucleases promote Mycobacterium tuberculosis drug tolerance and virulence in guinea pigs. Nat Commun. 2015 Jan 22;6:6059. doi: 10.1038/ncomms7059. PMID:25608501 doi:http://dx.doi.org/10.1038/ncomms7059
↑ Hoffer ED, Miles SJ, Dunham CM. The structure and function of Mycobacterium tuberculosis MazF-mt6 provides insights into conserved features of MazF endonucleases. J Biol Chem. 2017 Mar 15. pii: jbc.M117.779306. doi: 10.1074/jbc.M117.779306. PMID:28298445 doi:http://dx.doi.org/10.1074/jbc.M117.779306

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5uct"

@@ Line 1: / Line 1: @@
 ==Mycobacterium tuberculosis toxin MazF-mt6==
-<StructureSection load='5uct' size='340' side='right' caption='[[5uct]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
+<StructureSection load='5uct' size='340' side='right'caption='[[5uct]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5uct]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5UCT OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5UCT FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5uct]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Myctu Myctu]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5UCT OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=5UCT FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
+</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5uct FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5uct OCA], [http://pdbe.org/5uct PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5uct RCSB], [http://www.ebi.ac.uk/pdbsum/5uct PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5uct ProSAT]</span></td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">mazF3, mazF-mt6, Rv1102c ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83332 MYCTU])</td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=5uct FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5uct OCA], [http://pdbe.org/5uct PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5uct RCSB], [http://www.ebi.ac.uk/pdbsum/5uct PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5uct ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 20: / Line 21: @@
 ==See Also==
-*[[Endonuclease|Endonuclease]]
+*[[Endonuclease 3D structures|Endonuclease 3D structures]]
 == References ==
 <references/>
 __TOC__
 </StructureSection>
+[[Category: Large Structures]]
+[[Category: Myctu]]
 [[Category: Dunham, C M]]
 [[Category: Hoffer, E H]]

5uct

From Proteopedia

Revision as of 12:32, 23 September 2020

Mycobacterium tuberculosis toxin MazF-mt6

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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