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. 1991 Dec 11;19(23):6465–6468. doi: 10.1093/nar/19.23.6465

Stereochemistry of methyl transfer catalyzed by tRNA (m5U54)-methyltransferase--evidence for a single displacement mechanism.

J T Kealey 1, S Lee 1, H G Floss 1, D V Santi 1
PMCID: PMC329199  PMID: 1754383

Abstract

tRNA (m5U54)-methyltransferase (RUMT) catalyzes the transfer of a methyl group from S-adenosyl-L-methionine (AdoMet) to the 5-carbon of uridine 54 of tRNA. We have determined the steric course of methyl transfer, using (methyl-R)- and (methyl-S)-[methyl-2H1,3H]-AdoMet as the chiral methyl donors, and tRNA lacking the 5-methyl group at position 54 as the acceptor. Following methyl transfer, ribothymidine was isolated and degraded to chiral acetic acid for configurational analysis. Transfer of the chiral methyl group to U54 proceeded with inversion of configuration of the chiral methyl group, suggesting that RUMT catalyzed methyl transfer occurs by a single SN2 displacement mechanism.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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