EMD-50089

Helical reconstruction
2.9 Å
EMD-50089 Deposition: 12/04/2024
Map released: 27/11/2024
Last modified: 27/11/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-50089

CryoEM structure of the contracted sheath in H. borinquense

EMD-50089

Helical reconstruction
2.9 Å
EMD-50089 Deposition: 12/04/2024
Map released: 27/11/2024
Last modified: 27/11/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Halogeometricum borinquense DSM 11551
Sample: The sheath protein of Halogeometricum borinquense
Fitted models: 9ezm (Avg. Q-score: 0.621)

Deposition Authors: Zachs T , Malit JJ, Xu J , Schuerch A, Sivabalasarma S , Nussbaum P, Albers SV , Pilhofer M
Archaeal type six secretion system mediates contact-dependent antagonism.
Zachs T , Malit JJL , Xu J , Schurch A , Sivabalasarma S , Nussbaum P, Albers SV , Pilhofer M
(2024) Sci Adv , 10 , eadp7088 - eadp7088
PUBMED: 39546591
DOI: doi:10.1126/sciadv.adp7088
ISSN: 2375-2548
Abstract:
Microbial communities are shaped by cell-cell interactions. Although archaea are often found in associations with other microorganisms, the mechanisms structuring these communities are poorly understood. Here, we report on the structure and function of haloarchaeal contractile injection systems (CISs). Using a combination of functional assays and time-lapse imaging, we show that Halogeometricum borinquense exhibits antagonism toward Haloferax volcanii by inducing cell lysis and inhibiting proliferation. This antagonism is contact-dependent and requires a functional CIS, which is encoded by a gene cluster that is associated with toxin-immunity pairs. Cryo-focused ion beam milling and imaging by cryo-electron tomography revealed that these CISs are bound to the cytoplasmic membrane, resembling the bacterial type six secretion systems (T6SSs). We show that related T6SS gene clusters are conserved and expressed in other haloarchaeal strains, which exhibit antagonistic behavior. Our data provide a mechanistic framework for understanding how archaea may shape microbial communities and affect the food webs they inhabit.