3G5O

The crystal structure of the toxin-antitoxin complex RelBE2 (Rv2865-2866) from Mycobacterium tuberculosis

Summary for 3G5O

• Entry DOI: 10.2210/pdb3g5o/pdb
• Descriptor: Uncharacterized protein Rv2865, Uncharacterized protein Rv2866, THIOCYANATE ION, ... (8 entities in total)
• Functional Keywords: heterotetramer, 1:1 ratio, structural genomics, psi-2, protein structure initiative, tb structural genomics consortium, tbsgc, integrated center for structure and function innovation, isfi, toxin-antitoxin complex, toxin/antitoxin
• Biological source: Mycobacterium tuberculosis; More
• Total number of polymer chains: 4
• Total formula weight: 48248.83

Authors

Miallau, L.,Cascio, D.,Eisenberg, D.,TB Structural Genomics Consortium (TBSGC),Integrated Center for Structure and Function Innovation (ISFI) (deposition date: 2009-02-05, release date: 2009-04-14, Last modification date: 2024-05-22)

Primary citation

Miallau, L.,Jain, P.,Arbing, M.A.,Cascio, D.,Phan, T.,Ahn, C.J.,Chan, S.,Chernishof, I.,Maxson, M.,Chiang, J.,Jacobs Jr., W.R.,Eisenberg, D.S.
Comparative proteomics identifies the cell-associated lethality of M. tuberculosis RelBE-like toxin-antitoxin complexes.
Structure, 21:627-637, 2013

PubMed Abstract: The Mycobacterium tuberculosis (Mtb) genome encodes approximately 90 toxin-antitoxin protein complexes, including three RelBE family members, which are believed to play a major role in bacterial fitness and pathogenicity. We have determined the crystal structures of Mtb RelBE-2 and RelBE-3, and the structures reveal homologous heterotetramers. Our structures suggest RelE-2, and by extension the closely related RelE-1, use a different catalytic mechanism than RelE-3, because our analysis of the RelE-2 structure predicts additional amino acid residues that are likely to be functionally significant and are missing from analogous positions in the RelE-3 structure. Toxicity assays corroborate our structural findings; overexpression of RelE-3, whose active site is more similar to Escherichia coli YoeB, has limited consequences on bacterial growth, whereas RelE-1 and RelE-2 overexpression results in acute toxicity. Moreover, RelE-2 overexpression results in an elongated cell phenotype in Mycobacterium smegmatis and protects M. tuberculosis against antibiotics, suggesting a different functional role for RelE-2.

PubMed: 23523424
DOI: 10.1016/j.str.2013.02.008

Experimental method

X-RAY DIFFRACTION (2 Å)