tRNA nuclease CdiA

UniProtKB accession:  A0A1S4NYE3

Grouped By:  Matching UniProtKB accession

UniProtKB description:  Toxic component of a toxin-immunity protein module, which functions as a cellular contact-dependent growth inhibition (CDI) system. CDI modules allow bacteria to communicate with and inhibit the growth of closely related neighboring target bacteria in a contact-dependent fashion (target cell counts decrease 1000- to 10000-fold with this CDI) (PubMed:28351921, PubMed:29923643). Uses outer membrane nucleoside transporter Tsx on target cells as a receptor (PubMed:28351921). Gains access to the cytoplasm of target cells by using integral inner membrane protein PTS system glucose-specific EIICB component (ptsG) (Probable). Targeting of the C-terminal domain (CT) domain (residues 2931-3253) in the absence of immunity protein inhibits cell growth and causes tRNA(UUC-Glu) cleavage; expression of cognate immunity protein CdiI-STECO31 neutralizes growth inhibition leaving tRNA(UUC-Glu) is intact, whereas non-cognate immunity proteins do not confer protection (PubMed:29923643). The CT domain cleaves tRNA; it is most active against tRNA(UUC-Glu), but also has modest activity against tRNA(GUC-Asp), tRNA(UUG-Gln), tRNA(CCC-Gly), tRNA(UCC-Gly), tRNA(GCC-Gly), tRNA(UUU-Lys), tRNA(GGU-Thr) and tRNA(CCA-Trp); tRNA cleavage is inhibited by cognate immunity protein CdiI. Cleavage of tRNA(UUC-Glu) occurs in the anticodon loop between cytosine(37) and 2-methyladenosine(38) (C37-m2A38) and probably also occurs in the anticodon loop of other tRNAs as well (PubMed:29923643).