کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1392008 | 983697 | 2009 | 11 صفحه PDF | دانلود رایگان |
SummaryHere we report the in vitro selection of an unusual ribozyme that efficiently performs nucleotide synthesis even though it was selected to perform a distinctly different sugar chemistry. This ribozyme, called pR1, when derivatized with ribose 5-phosphate (PR) at its 3′ terminus and incubated with 6-thioguanine, produces two interconverting thiol-containing products corresponding to a Schiff base and its Amadori rearranged product. Consistent with this hypothesis, removing the 2-hydroxyl from the PR substrate results in only a single product. Surprisingly, as this was not selected for, switching the tethered PR substrate to 5-phosphoribosyl 1-pyrophosphate results in the synthesis of 6-thioguanosine 5′-monophosphate. The discovery that a ribozyme can promote such distinct reactions spontaneously demonstrates that an RNA-mediated metabolism early in evolution could have evolved important new functionalities via ribozyme promiscuity.
Journal: - Volume 16, Issue 8, 28 August 2009, Pages 815–825