2.7.7.48 | 5-fluorouridine triphosphate + RNAn |
the enzyme incorporates 5-fluorouridine monophosphate during RNA elongation in place of UMP or CMP using homopolymeric and heteropolymeric templates. Incorporation of 5-fluorouridine monophosphate does not prevent chain elongation, and, in some sequence contexts, it favors misincorporations at downstream positions. 5-Fluorouridine monophosphate is incorporated into the nascent RNA and occupies the new 3'-end of the primer at the active site of the enzyme. 5-Fluorouridine monophosphate establishes a Watson and Crick pair with the corresponding acceptor AMP in the template strand and an additional hydrogen bond with Ser304 of the polymerase. Further interactions, similar to those observed with standard nucleotides, contribute also to stabilize 5-fluorouridine monophosphate in the 3'-terminus of the RNA. When present in the template, 5-fluorouridine monophosphate directs the incorporation of AMP and GMP, with ATP being a more effective substrate than GTP. The misincorporation of GMP is 17fold faster opposite 5-fluorouridine than opposite U in the template. But Incorporated 5-fluorouridine monophosphate is not a chain terminator during RNA elongation |
Foot-and-mouth disease virus |
diphosphate + RNAn+1 |
RNA with incoporated 5-fluorouridine phosphate |
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