Specific interaction between anticodon nuclease and the tRNA(Lys) wobble base.
The bacterial tRNA(Lys)-specific PrrC-anticodon nuclease cleaves its natural substrate 5' to the wobble base, yielding 2',3'-cyclic phosphate termini. Previous work has implicated the anticodon of tRNA(Lys) as a specificity element and a cluster of amino acid residues at the carboxy-proximal half of PrrC in its recognition. We further examined these assumptions by assaying unmodified and hypomodified derivatives of tRNA(Lys) as substrates of wild-type and mutant alleles of PrrC. The data show, first, that the anticodon sequence and wobble base modifications of tRNA(Lys) play major roles in the interaction with anticodon nuclease. Secondly, a specific contact between the substrate recognition site of PrrC and the tRNA(Lys) wobble base is revealed by PrrC missense mutations that suppress the inhibitory effects of wobble base modification mutations. Thirdly, the data distinguish between the anticodon recognition mechanisms of PrrC and lysyl-tRNA synthetase.
Jiang
Y
Y
Department of Biochemistry, Tel Aviv University, Ramat Aviv 69978, Israel.
Meidler
R
R
Amitsur
M
M
Kaufmann
G
G
D000483:Alleles; D000595:Amino Acid Sequence; D000926:Anticodon / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial / Q000235:genetics / Q000502:physiology; D008250:Lysine-tRNA Ligase / Q000378:metabolism; D008969:Molecular Sequence Data; D020125:Mutation, Missense / Q000235:genetics; D017354:Point Mutation / Q000235:genetics; D017433:Protein Structure, Secondary; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012357:RNA, Transfer, Lys / Q000235:genetics* / Q000378:metabolism*; D012260:Ribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity; D013489:Suppression, Genetic / Q000235:genetics; D012359:tRNA Methyltransferases / Q000235:genetics / Q000378:metabolism
D000926:Anticodon; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; D012357:RNA, Transfer, Lys; D012359:tRNA Methyltransferases; C084965:PrrC protein, E coli; D012260:Ribonucleases; C049345:anticodon nuclease; D008250:Lysine-tRNA Ligase