Publication Date:
2009-12-08
Description:
Primordial organisms of the putative RNA world would have required polymerase ribozymes able to replicate RNA. Known ribozymes with polymerase activity best approximating that needed for RNA replication contain at their catalytic core the class I RNA ligase, an artificial ribozyme with a catalytic rate among the fastest of known ribozymes. Here we present the 3.0 angstrom crystal structure of this ligase. The architecture resembles a tripod, its three legs converging near the ligation junction. Interacting with this tripod scaffold through a series of 10 minor-groove interactions (including two A-minor triads) is the unpaired segment that contributes to and organizes the active site. A cytosine nucleobase and two backbone phosphates abut the ligation junction; their location suggests a model for catalysis resembling that of proteinaceous polymerases.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3978776/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3978776/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Shechner, David M -- Grant, Robert A -- Bagby, Sarah C -- Koldobskaya, Yelena -- Piccirilli, Joseph A -- Bartel, David P -- GM61835/GM/NIGMS NIH HHS/ -- R01 GM061835/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2009 Nov 27;326(5957):1271-5. doi: 10.1126/science.1174676.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Whitehead Institute for Biomedical Research and Howard Hughes Medical Institute, 9 Cambridge Center, Cambridge, MA 02142, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19965478" target="_blank"〉PubMed〈/a〉
Keywords:
Base Pairing
;
Base Sequence
;
Catalysis
;
Catalytic Domain
;
Crystallization
;
Crystallography, X-Ray
;
DNA-Directed RNA Polymerases/chemistry/metabolism
;
Hydrogen Bonding
;
Hydrogen-Ion Concentration
;
Magnesium/chemistry/metabolism
;
Models, Molecular
;
Molecular Sequence Data
;
Nucleic Acid Conformation
;
Polynucleotide Ligases/chemistry/metabolism
;
RNA, Catalytic/*chemistry/metabolism
;
Ribonucleotides/chemistry/metabolism
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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