9ARD

Structure of Pycsar EcPycC cyclase immunoglobulin-like AGS-C domain

Summary for 9ARD

• Entry DOI: 10.2210/pdb9ard/pdb
• Descriptor: Cytidylate cyclase (2 entities in total)
• Functional Keywords: pycsar, ags-c, antiphage defense, unknown function
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 30767.42

Authors

Richmond-Buccola, D.,Kranzusch, P.J. (deposition date: 2024-02-23, release date: 2024-06-19, Last modification date: 2024-07-24)

Primary citation

Richmond-Buccola, D.,Hobbs, S.J.,Garcia, J.M.,Toyoda, H.,Gao, J.,Shao, S.,Lee, A.S.Y.,Kranzusch, P.J.
A large-scale type I CBASS antiphage screen identifies the phage prohead protease as a key determinant of immune activation and evasion.
Cell Host Microbe, 32:1074-1088.e5, 2024

PubMed Abstract: Cyclic oligonucleotide-based signaling system (CBASS) is an antiviral system that protects bacteria from phage infection and is evolutionarily related to human cGAS-STING immunity. cGAS-STING signaling is initiated by the recognition of viral DNA, but the molecular cues activating CBASS are incompletely understood. Using a screen of 975 type I CBASS operon-phage challenges, we show that operons with distinct cGAS/DncV-like nucleotidyltransferases (CD-NTases) and CD-NTase-associated protein (Cap) effectors exhibit marked patterns of phage restriction. We find that some type I CD-NTase enzymes require a C-terminal AGS-C immunoglobulin (Ig)-like fold domain for defense against select phages. Escaper phages evade CBASS via protein-coding mutations in virion assembly proteins, and acquired resistance is largely operon specific. We demonstrate that the phage Bas13 prohead protease interacts with the CD-NTase EcCdnD12 and can induce CBASS-dependent growth arrest in cells. Our results define phage virion assembly as a determinant of type I CBASS immune evasion and support viral protein recognition as a putative mechanism of cGAS-like enzyme activation.

PubMed: 38917809
DOI: 10.1016/j.chom.2024.05.021

Experimental method

X-RAY DIFFRACTION (1.63 Å)