8JSK

Crystal structure of an N-terminal cyclic nucleotide-binding domain of a PycTIR from Pseudovibrio sp. in complex with cUMP

Summary for 8JSK

• Entry DOI: 10.2210/pdb8jsk/pdb
• Related: 8JSF 8JSJ
• Descriptor: PycTIR, Uridine-3',5'-cyclic monophosphate (3 entities in total)
• Functional Keywords: cump receptor, pycsar effector protein, signaling protein
• Biological source: Pseudovibrio sp. W64
• Total number of polymer chains: 2
• Total formula weight: 35998.99

Authors

Wang, Y.-C.,Yang, C.-S.,Hou, M.-H.,Chen, Y. (deposition date: 2023-06-20, release date: 2024-07-03, Last modification date: 2024-07-17)

Primary citation

Hou, M.H.,Chen, C.J.,Yang, C.S.,Wang, Y.C.,Chen, Y.
Structural and functional characterization of cyclic pyrimidine-regulated anti-phage system.
Nat Commun, 15:5634-5634, 2024

PubMed Abstract: 3',5'-cyclic uridine monophosphate (cUMP) and 3',5'-cyclic cytidine monophosphate (cCMP) have been established as bacterial second messengers in the phage defense system, named pyrimidine cyclase system for anti-phage resistance (Pycsar). This system consists of a pyrimidine cyclase and a cyclic pyrimidine receptor protein. However, the molecular mechanism underlying cyclic pyrimidine synthesis and recognition remains unclear. Herein, we determine the crystal structures of a uridylate cyclase and a cytidylate cyclase, revealing the conserved residues for cUMP and cCMP production, respectively. In addition, a distinct zinc-finger motif of the uridylate cyclase is identified to confer substantial resistance against phage infections. Furthermore, structural characterization of cUMP receptor protein PycTIR provides clear picture of specific cUMP recognition and identifies a conserved N-terminal extension that mediates PycTIR oligomerization and activation. Overall, our results contribute to the understanding of cyclic pyrimidine-mediated bacterial defense.

PubMed: 38965224
DOI: 10.1038/s41467-024-49861-2

Experimental method

X-RAY DIFFRACTION (2.401 Å)