Crystal Structure of RNase T, an Exoribonuclease Involved in tRNA Maturation and End Turnover

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Structure

DOI:https://doi.org/10.1016/j.str.2007.02.004· OSTI ID:930365

Zuo, Y; Zheng, H; Wang, Y; Chruszcz, M; Cymborowski, M; Skarina, T; Savchenko, A; Malhotra, A; Minor, W

The 3 processing of most bacterial precursor tRNAs involves exonucleolytic trimming to yield a mature CCA end. This step is carried out by RNase T, a member of the large DEDD family of exonucleases. We report the crystal structures of RNase T from Escherichia coli and Pseudomonas aeruginosa, which show that this enzyme adopts an opposing dimeric arrangement, with the catalytic DEDD residues from one monomer closely juxtaposed with a large basic patch on the other monomer. This arrangement suggests that RNase T has to be dimeric for substrate specificity, and agrees very well with prior site-directed mutagenesis studies. The dimeric architecture of RNase T is very similar to the arrangement seen in oligoribonuclease, another bacterial DEDD family exoribonuclease. The catalytic residues in these two enzymes are organized very similarly to the catalytic domain of the third DEDD family exoribonuclease in E. coli, RNase D, which is monomeric.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 930365
• Report Number(s): BNL--81084-2008-JA
• Journal Information: Structure, Journal Name: Structure Vol. 15; ISSN 0969-2126
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL STRUCTURE
ENZYMES
ESCHERICHIA COLI
MONOMERS
MUTAGENESIS
PRECURSOR
PSEUDOMONAS
RESIDUES
RNA-ASE
SPECIFICITY
SUBSTRATES
national synchrotron light source