6IVS
Solution structure of the N-terminal domain of the anti-sigma factor RsgI1 from Clostridium thermocellum
Summary for 6IVS
| Entry DOI | 10.2210/pdb6ivs/pdb |
| NMR Information | BMRB: 36220 |
| Descriptor | Anti-sigma-I factor RsgI1 (1 entity in total) |
| Functional Keywords | anti-sigma factor, transcription |
| Biological source | Hungateiclostridium thermocellum ATCC 27405 (Ruminiclostridium thermocellum) |
| Total number of polymer chains | 1 |
| Total formula weight | 6170.17 |
| Authors | |
| Primary citation | Wei, Z.,Chen, C.,Liu, Y.J.,Dong, S.,Li, J.,Qi, K.,Liu, S.,Ding, X.,Ortiz de Ora, L.,Munoz-Gutierrez, I.,Li, Y.,Yao, H.,Lamed, R.,Bayer, E.A.,Cui, Q.,Feng, Y. Alternative sigma I/anti-sigma I factors represent a unique form of bacterial sigma /anti-sigma complex. Nucleic Acids Res., 47:5988-5997, 2019 Cited by PubMed Abstract: The σ70 family alternative σI factors and their cognate anti-σI factors are widespread in Clostridia and Bacilli and play a role in heat stress response, virulence, and polysaccharide sensing. Multiple σI/anti-σI factors exist in some lignocellulolytic clostridial species, specifically for regulation of components of a multienzyme complex, termed the cellulosome. The σI and anti-σI factors are unique, because the C-terminal domain of σI (SigIC) and the N-terminal inhibitory domain of anti-σI (RsgIN) lack homology to known proteins. Here, we report structure and interaction studies of a pair of σI and anti-σI factors, SigI1 and RsgI1, from the cellulosome-producing bacterium, Clostridium thermocellum. In contrast to other known anti-σ factors that have N-terminal helical structures, RsgIN has a β-barrel structure. Unlike other anti-σ factors that bind both σ2 and σ4 domains of the σ factors, RsgIN binds SigIC specifically. Structural analysis showed that SigIC contains a positively charged surface region that recognizes the promoter -35 region, and the synergistic interactions among multiple interfacial residues result in the specificity displayed by different σI/anti-σI pairs. We suggest that the σI/anti-σI factors represent a distinctive mode of σ/anti-σ complex formation, which provides the structural basis for understanding the molecular mechanism of the intricate σI/anti-σI system. PubMed: 31106374DOI: 10.1093/nar/gkz355 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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