Download MendeleyCrystal structure and functional implications of cyclic di-pyrimidine-synthesizing cGAS/DncV-like nucleotidyltransferases.
Yang, C.S., Ko, T.P., Chen, C.J., Hou, M.H., Wang, Y.C., Chen, Y.(2023) Nat Commun 14: 5078-5078
- PubMed: 37604815
- DOI: https://doi.org/10.1038/s41467-023-40787-9
- Primary Citation of Related Structures:
7X4A, 7X4C, 7X4F, 7X4G, 7X4P, 7X4Q, 7X4T, 8HYK - PubMed Abstract:
Purine-containing nucleotide second messengers regulate diverse cellular activities. Cyclic di-pyrimidines mediate anti-phage functions in bacteria; however, the synthesis mechanism remains elusive. Here, we determine the high-resolution structures of cyclic di-pyrimidine-synthesizing cGAS/DncV-like nucleotidyltransferases (CD-NTases) in clade E (CdnE) in its apo, substrate-, and intermediate-bound states. A conserved (R/Q)xW motif controlling the pyrimidine specificity of donor nucleotide is identified. Mutation of Trp or Arg from the (R/Q)xW motif to Ala rewires its specificity to purine nucleotides, producing mixed purine-pyrimidine cyclic dinucleotides (CDNs). Preferential binding of uracil over cytosine bases explains the product specificity of cyclic di-pyrimidine-synthesizing CdnE to cyclic di-UMP (cUU). Based on the intermediate-bound structures, a synthetic pathway for cUU containing a unique 2'3'-phosphodiester linkage through intermediate pppU[3'-5']pU is deduced. Our results provide a framework for pyrimidine selection and establish the importance of conserved residues at the C-terminal loop for the specificity determination of CD-NTases.
Organizational Affiliation:
Genomics BioSci & Tech Co. Ltd., New Taipei, 221, Taiwan.
