+Search query
-Structure paper
Title | Cytoplasmic contractile injection systems mediate cell death in Streptomyces. |
---|---|
Journal, issue, pages | Nat Microbiol, Vol. 8, Issue 4, Page 711-726, Year 2023 |
Publish date | Mar 9, 2023 |
Authors | Bastien Casu / Joseph W Sallmen / Susan Schlimpert / Martin Pilhofer / |
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 ...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. |
External links | Nat Microbiol / PubMed:36894633 / PubMed Central |
Methods | EM (helical sym.) / EM (tomography) |
Resolution | 3.6 - 3.9 Å |
Structure data | EMDB-16098, PDB-8bky: EMDB-16101, PDB-8bl4: EMDB-16200: Cryo electron tomogram of Streptomyces coelicolor - Example 1 EMDB-16201: Cryo electron tomogram of Streptomyces coelicolor - Intact hyphae EMDB-16202: Cryo electron tomogram of Streptomyces coelicolor - Partially lysed hyphae EMDB-16203: Cryo electron tomogram of Streptomyces coelicolor - Ghost cells EMDB-16204: The contractile injection system in Streptomyces venezuelae EMDB-16205: Cryo electron tomogram of Streptomyces coelicolor - Cis2-Ypet sandwich fusion EMDB-16206: Cryo electron tomogram of Streptomyces coelicolor - Example 2 EMDB-16208: Cryo electron tomogram of Streptomyces coelicolor - Example 3 EMDB-16210: Cryo electron tomogram of Streptomyces coelicolor - ScoDelta4256-4258 effector mutant |
Source |
|
Keywords | STRUCTURAL PROTEIN / Contractile injection system |