2pjd
From Proteopedia
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| , resolution 2.10Å | |||||||
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| Ligands: | |||||||
| Gene: | rsmC (Escherichia coli) | ||||||
| Activity: | rRNA (guanine-N(2)-)-methyltransferase, with EC number 2.1.1.52 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of 16S rRNA methyltransferase RsmC
Overview
RNA methyltransferases (MTases) are important players in the biogenesis and regulation of the ribosome, the cellular machine for protein synthesis. RsmC is a MTase that catalyzes the transfer of a methyl group from S-adenosyl-l-methionine (SAM) to G1207 of 16S rRNA. Mutations of G1207 have dominant lethal phenotypes in Escherichia coli, underscoring the significance of this modified nucleotide for ribosome function. Here we report the crystal structure of E. coli RsmC refined to 2.1 A resolution, which reveals two homologous domains tandemly duplicated within a single polypeptide. We characterized the function of the individual domains and identified key residues involved in binding of rRNA and SAM, and in catalysis. We also discovered that one of the domains is important for the folding of the other. Domain duplication and subfunctionalization by complementary degeneration of redundant functions (in particular substrate binding versus catalysis) has been reported for many enzymes, including those involved in RNA metabolism. Thus, RsmC can be regarded as a model system for functional streamlining of domains accompanied by the development of dependencies concerning folding and stability.
About this Structure
2PJD is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Functional specialization of domains tandemly duplicated within 16S rRNA methyltransferase RsmC., Sunita S, Purta E, Durawa M, Tkaczuk KL, Swaathi J, Bujnicki JM, Sivaraman J, Nucleic Acids Res. 2007;35(13):4264-74. Epub 2007 Jun 18. PMID:17576679
Page seeded by OCA on Mon Mar 31 04:36:43 2008
