Epoxyqueuosine Reductase Structure Suggests a Mechanism for Cobalamin-dependent tRNA Modification
نویسندگان
چکیده
منابع مشابه
Molecular basis of cobalamin-dependent RNA modification
Queuosine (Q) was discovered in the wobble position of a transfer RNA (tRNA) 47 years ago, yet the final biosynthetic enzyme responsible for Q-maturation, epoxyqueuosine (oQ) reductase (QueG), was only recently identified. QueG is a cobalamin (Cbl)-dependent, [4Fe-4S] cluster-containing protein that produces the hypermodified nucleoside Q in situ on four tRNAs. To understand how QueG is able to...
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The reduction of epoxyqueuosine (oQ) is the last step in the synthesis of the tRNA modification queuosine (Q). While the epoxyqueuosine reductase (EC 1.17.99.6) enzymatic activity was first described 30 years ago, the encoding gene queG was only identified in Escherichia coli in 2011. Interestingly, queG is absent from a large number of sequenced genomes that harbor Q synthesis or salvage genes...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 2015
ISSN: 0021-9258
DOI: 10.1074/jbc.m115.685693