7u2s

Structure of Paenibacillus xerothermodurans Apyc1 in the apo stateStructure of Paenibacillus xerothermodurans Apyc1 in the apo state

Structural highlights 7u2s is a 2 chain structure with sequence from Paenibacillus xerothermodurans. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.55Å Ligands: Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function APYC1_PAEXE Counteracts the endogenous Pycsar antiviral defense system. Phosphodiesterase that enables metal-dependent hydrolysis of host cyclic nucleotide Pycsar defense signals such as cCMP and cUMP. Publication Abstract from PubMed CBASS and Pycsar are anti-phage defense systems in diverse bacteria that use cyclic nucleotide signals to induce cell death and prevent viral propagation(1,2). Phages use multiple strategies to defeat host CRISPR and restriction-modification systems(3-10), but no mechanisms are known to evade CBASS and Pycsar immunity. Here we show that phages encode anti-CBASS (Acb) and anti-Pycsar (Apyc) proteins that counteract defense by specifically degrading cyclic nucleotide signals that activate host immunity. Using a biochemical screen of 57 phages in E. coli and B. subtilis, we discover Acb1 from phage T4 and Apyc1 from phage SBSphiJ as founding members of distinct families of immune evasion proteins. Crystal structures of Acb1 in complex with 3'3'-cGAMP define a mechanism of metal-independent hydrolysis 3' of adenosine bases, enabling broad recognition and degradation of cyclic di- and trinucleotide CBASS signals. Structures of Apyc1 reveal a metal-dependent cNMP phosphodiesterase that uses relaxed specificity to target Pycsar cyclic pyrimidine mononucleotide signals. We show that Acb1 and Apyc1 block downstream effector activation and protect from CBASS and Pycsar defense in vivo. Active Acb1 and Apyc1 enzymes are conserved in phylogenetically diverse phages, demonstrating cleavage of host cyclic nucleotide signals is a key strategy of immune evasion in phage biology. Phage anti-CBASS and anti-Pycsar nucleases subvert bacterial immunity.,Hobbs SJ, Wein T, Lu A, Morehouse BR, Schnabel J, Leavitt A, Yirmiya E, Sorek R, Kranzusch PJ Nature. 2022 Apr 8. pii: 10.1038/s41586-022-04716-y. doi:, 10.1038/s41586-022-04716-y. PMID:35395152 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 7u2s, resolution 1.55Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image