Open AccessThe structure of the flexible arm of Thermotoga maritima tRNase Z differs from those of homologous enzymes
Author(s) -
Ishii Ryohei,
Minagawa Asako,
Takaku Hiroaki,
Takagi Masamichi,
Nashimoto Masayuki,
Yokoyama Shigeyuki
Publication year - 2007
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309107033623
Subject(s) - thermotoga maritima , endoribonuclease , transfer rna , escherichia coli , dimer , bacillus subtilis , aquifex aeolicus , stereochemistry , enzyme , biology , chemistry , biochemistry , rna , genetics , rnase p , gene , bacteria , organic chemistry
tRNA 3′‐processing endoribonuclease (tRNase Z) is one of the enzymes involved in the 3′‐end processing of precursor tRNAs and is a member of the metallo‐β‐lactamase superfamily. tRNase Z crystal structures have revealed that the enzyme forms a dimer and has a characteristic domain, named a flexible arm or an exosite, which protrudes from the metallo‐β‐lactamase core and is involved in tRNA binding. The refined structure of Thermotoga maritima tRNase Z has been determined at 1.97 Å resolution, revealing the structure of the flexible arm and the zinc‐bound active site. The structure of the flexible arm of T. maritima tRNase Z is distinct from those of the Bacillus subtilis and Escherichia coli tRNase Zs. A comparison of the three tRNase Z structures revealed differences in the dimer orientation, which may be related to the unique cleavage‐site specificity of T. maritima tRNase Z.