Structural and Mechanistic Analyses Reveal a Unique Cas4-like Protein in the Mimivirus Virophage Resistance Element System.
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ABSTRACT:
SUBMITTER: Dou C
PROVIDER: S-EPMC6137704 | biostudies-literature | 2018 May
REPOSITORIES: biostudies-literature
Publications
Structural and Mechanistic Analyses Reveal a Unique Cas4-like Protein in the Mimivirus Virophage Resistance Element System.
Dou Chao C Yu Mingjing M Gu Yijun Y Wang Jinjing J Yin Kun K Nie Chunlai C Zhu Xiaofeng X Qi Shiqian S Wei Yuquan Y Cheng Wei W
iScience 20180411
A clustered regularly interspaced short palindromic repeats (CRISPR)-like "mimivirus virophage resistance element" (MIMIVIRE) system, which contains specific cascade genes and a CRISPR array against virophages, was reported in mimiviruses. An essential component of the MIMIVIRE system is R354, encoding a nuclease and a likely functional homolog of Cas4. Here we show that R354 is a dual nuclease with both exonuclease and endonuclease activities. Structural analysis revealed that the catalytic cor ...[more]
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