Open AccessRNA-hydrolyzing activity of metallo-β-lactamase IMP-1
Author(s) -
Yoshiki Kato,
Masayuki Takahashi,
Mineaki Seki,
Masayuki Nashimoto,
Akiko ShimizuIbuka
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0241557
Subject(s) - endoribonuclease , biology , transfer rna , rna , biochemistry , thermotoga maritima , enzyme , rnase p , escherichia coli , gene
Metallo-β-lactamases (MBLs) hydrolyze a wide range of β-lactam antibiotics. While all MBLs share a common αβ/βα-fold, there are many other proteins with the same folding pattern that exhibit different enzymatic activities. These enzymes, together with MBLs, form the MBL superfamily. Thermotoga maritima tRNase Z, a tRNA 3′ processing endoribonuclease of MBL-superfamily, and IMP-1, a clinically isolated MBL, showed a striking similarity in tertiary structure, despite low sequence homology. IMP-1 hydrolyzed both total cellular RNA and synthetic small unstructured RNAs. IMP-1 also hydrolyzed pre-tRNA, but its cleavage site was different from those of T . maritima tRNase Z and human tRNase Z long form, indicating a key difference in substrate recognition. Single-turnover kinetic assays suggested that substrate-binding affinity of T . maritima tRNase Z is much higher than that of IMP-1.