8BKY
Cryo-EM structure of a contractile injection system in Streptomyces coelicolor, the contracted sheath shell.
Summary for 8BKY
| Entry DOI | 10.2210/pdb8bky/pdb |
| EMDB information | 16098 |
| Descriptor | Phage tail sheath protein (1 entity in total) |
| Functional Keywords | structural protein, contractile injection system |
| Biological source | Streptomyces coelicolor A3(2) |
| Total number of polymer chains | 24 |
| Total formula weight | 1368230.62 |
| Authors | Casu, B.,Sallmen, J.W.,Schlimpert, S.,Pilhofer, M. (deposition date: 2022-11-09, release date: 2023-03-15, Last modification date: 2024-07-24) |
| Primary citation | Casu, B.,Sallmen, J.W.,Schlimpert, S.,Pilhofer, M. Cytoplasmic contractile injection systems mediate cell death in Streptomyces. Nat Microbiol, 8:711-726, 2023 Cited by PubMed Abstract: Contractile injection systems (CIS) are bacteriophage tail-like structures that mediate bacterial cell-cell interactions. While CIS are highly abundant across diverse bacterial phyla, representative gene clusters in Gram-positive organisms remain poorly studied. Here we characterize a CIS in the Gram-positive multicellular model organism Streptomyces coelicolor and show that, in contrast to most other CIS, S. coelicolor CIS (CIS) mediate cell death in response to stress and impact cellular development. CIS are expressed in the cytoplasm of vegetative hyphae and are not released into the medium. Our cryo-electron microscopy structure enabled the engineering of non-contractile and fluorescently tagged CIS assemblies. Cryo-electron tomography showed that CIS contraction is linked to reduced cellular integrity. Fluorescence light microscopy furthermore revealed that functional CIS mediate cell death upon encountering different types of stress. The absence of functional CIS had an impact on hyphal differentiation and secondary metabolite production. Finally, we identified three putative effector proteins, which when absent, phenocopied other CIS mutants. Our results provide new functional insights into CIS in Gram-positive organisms and a framework for studying novel intracellular roles, including regulated cell death and life-cycle progression in multicellular bacteria. PubMed: 36894633DOI: 10.1038/s41564-023-01341-x PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.6 Å) |
Structure validation
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