Advanced

Catalysis by RNase P RNA. Unique Features and Unprecedented Active Site Plasticity.

Persson, Tina LU ; Cuzic, Simona and Hartmann, Roland K (2003) In Journal of Biological Chemistry 278(44). p.43394-43401
Abstract
Metal ions are essential cofactors for precursor tRNA (ptRNA) processing by bacterial RNase P. The ribose 2'-OH at nucleotide (nt) –1 of ptRNAs is known to contribute to positioning of catalytic Me2+. To investigate the catalytic process, we used ptRNAs with single 2'-deoxy (2'-H), 2'-amino (2'-N), or 2'-fluoro (2'-F) modifications at the cleavage site (nt –1). 2' modifications had small (2.4–7.7-fold) effects on ptRNA binding to E. coli RNase P RNA in the ground state, decreasing substrate affinity in the order 2'-OH > 2'-F > 2'-N > 2'-H. Effects on the rate of the chemical step (about 10-fold for 2'-F, almost 150-fold for 2'-H and 2'-N) were much stronger, and, except for the 2'-N modification, resembled strikingly those... (More)
Metal ions are essential cofactors for precursor tRNA (ptRNA) processing by bacterial RNase P. The ribose 2'-OH at nucleotide (nt) –1 of ptRNAs is known to contribute to positioning of catalytic Me2+. To investigate the catalytic process, we used ptRNAs with single 2'-deoxy (2'-H), 2'-amino (2'-N), or 2'-fluoro (2'-F) modifications at the cleavage site (nt –1). 2' modifications had small (2.4–7.7-fold) effects on ptRNA binding to E. coli RNase P RNA in the ground state, decreasing substrate affinity in the order 2'-OH > 2'-F > 2'-N > 2'-H. Effects on the rate of the chemical step (about 10-fold for 2'-F, almost 150-fold for 2'-H and 2'-N) were much stronger, and, except for the 2'-N modification, resembled strikingly those observed in the Tetrahymena ribozyme-catalyzed reaction at corresponding position. Mn2+ rescued cleavage of the 2'-N but also the 2'-H-modified ptRNA, arguing against a direct metal ion coordination at this location. Miscleavage between nt –1 and –2 was observed for the 2'-N-ptRNA at low pH (further influenced by the base identities at nt –1 and +73), suggesting repulsion of a catalytic metal ion due to protonation of the amino group. Effects caused by the 2'-N modification at nt –1 of the substrate allowed us to substantiate a mechanistic difference in phosphodiester hydrolysis catalyzed by Escherichia coli RNase P RNA and the Tetrahymena ribozyme: a metal ion binds next to the 2' substituent at nt –1 in the reaction catalyzed by RNase P RNA, but not at the corresponding location in the Tetrahymena ribozyme reaction. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Biological Chemistry
volume
278
issue
44
pages
43394 - 43401
publisher
ASBMB
external identifiers
  • scopus:0242321976
ISSN
1083-351X
DOI
10.1074/jbc.M305939200
language
English
LU publication?
yes
id
e83f2fbf-e01b-45c7-bcd5-8c87abe758e1 (old id 128584)
date added to LUP
2007-07-10 13:34:32
date last changed
2018-05-29 11:31:57
@article{e83f2fbf-e01b-45c7-bcd5-8c87abe758e1,
  abstract     = {Metal ions are essential cofactors for precursor tRNA (ptRNA) processing by bacterial RNase P. The ribose 2'-OH at nucleotide (nt) –1 of ptRNAs is known to contribute to positioning of catalytic Me2+. To investigate the catalytic process, we used ptRNAs with single 2'-deoxy (2'-H), 2'-amino (2'-N), or 2'-fluoro (2'-F) modifications at the cleavage site (nt –1). 2' modifications had small (2.4–7.7-fold) effects on ptRNA binding to E. coli RNase P RNA in the ground state, decreasing substrate affinity in the order 2'-OH > 2'-F > 2'-N > 2'-H. Effects on the rate of the chemical step (about 10-fold for 2'-F, almost 150-fold for 2'-H and 2'-N) were much stronger, and, except for the 2'-N modification, resembled strikingly those observed in the Tetrahymena ribozyme-catalyzed reaction at corresponding position. Mn2+ rescued cleavage of the 2'-N but also the 2'-H-modified ptRNA, arguing against a direct metal ion coordination at this location. Miscleavage between nt –1 and –2 was observed for the 2'-N-ptRNA at low pH (further influenced by the base identities at nt –1 and +73), suggesting repulsion of a catalytic metal ion due to protonation of the amino group. Effects caused by the 2'-N modification at nt –1 of the substrate allowed us to substantiate a mechanistic difference in phosphodiester hydrolysis catalyzed by Escherichia coli RNase P RNA and the Tetrahymena ribozyme: a metal ion binds next to the 2' substituent at nt –1 in the reaction catalyzed by RNase P RNA, but not at the corresponding location in the Tetrahymena ribozyme reaction.},
  author       = {Persson, Tina and Cuzic, Simona and Hartmann, Roland K},
  issn         = {1083-351X},
  language     = {eng},
  number       = {44},
  pages        = {43394--43401},
  publisher    = {ASBMB},
  series       = {Journal of Biological Chemistry},
  title        = {Catalysis by RNase P RNA. Unique Features and Unprecedented Active Site Plasticity.},
  url          = {http://dx.doi.org/10.1074/jbc.M305939200},
  volume       = {278},
  year         = {2003},
}