Dataset Information

Type III-B CRISPR-Cas signaling-based cascade of proteolytic cleavages

ABSTRACT: Characteristic for type III CRISPR-Cas systems is the generation of cyclic oligoadenylate (cOA) molecules, which allosterically activate proteins carrying cognate sensory domains: CARF or SAVED. Here, we characterize a type III-B system associated set of genes from Haliangium ochraceum, containing two CBASS co-opted caspase-like proteases, SAVED-CHAT and PCaspase (Prokaryotic Caspase). Cyclic tri-AMP (cA3)- induced oligomerization of the SAVED domains of SAVED-CHAT leads to proteolytic activity of the CHAT domains which, when active, specifically cleave and activate PCaspase. In turn, activated PCaspase cleaves a multitude of proteins and leads to a strong defence mechanism in vivo in E. coli.. Together, our findings show a cascade of proteolytic activities (with conceptual similarities to eukaryotic caspases) and constitute an effective strategy to defend against mobile genetic elements.

INSTRUMENT(S):

ORGANISM(S): Haliangium Ochraceum Dsm 14365

SUBMITTER: Richard Scheltema

LAB HEAD: Richard Scheltema

PROVIDER: PXD046897 | Pride | 2025-05-06

REPOSITORIES: Pride

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			Action	DRS
	20230927_EX1_UM8_baren111_SA_EXT00_band2p1.raw	Raw
	20230927_EX1_UM8_baren111_SA_EXT00_band2p2.raw	Raw
	20230927_EX1_UM8_baren111_SA_EXT00_band2p3.raw	Raw
	20230927_EX1_UM8_baren111_SA_EXT00_band2p4.raw	Raw
	20230927_EX1_UM8_baren111_SA_EXT00_band2p5.raw	Raw

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Type III-B CRISPR-Cas cascade of proteolytic cleavages.

Steens Jurre A JA Bravo Jack P K JPK Salazar Carl Raymund P CRP Yildiz Caglar C Amieiro Afonso M AM Köstlbacher Stephan S Prinsen Stijn H P SHP Andres Ane S AS Patinios Constantinos C Bardis Andreas A Barendregt Arjan A Scheltema Richard A RA Ettema Thijs J G TJG van der Oost John J Taylor David W DW Staals Raymond H J RHJ

Science (New York, N.Y.) 20240201 6682

The generation of cyclic oligoadenylates and subsequent allosteric activation of proteins that carry sensory domains is a distinctive feature of type III CRISPR-Cas systems. In this work, we characterize a set of associated genes of a type III-B system from <i>Haliangium ochraceum</i> that contains two caspase-like proteases, SAVED-CHAT and PCaspase (prokaryotic caspase), co-opted from a cyclic oligonucleotide-based antiphage signaling system (CBASS). Cyclic tri-adenosine monophosphate (AMP)-ind ...[more]

PMID: 38301007

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