The NTP binding site of the polymerase ribozyme.

ABSTRACT: A previously developed RNA polymerase ribozyme uses nucleoside triphosphates (NTPs) to extend a primer 3'-terminus, templated by an RNA template with good fidelity, forming 3'-5'-phosphordiester bonds. Indirect evidence has suggested that the ribozyme's accessory domain binds the NTP with a highly conserved purine-rich loop. To determine the NTP binding site more precisely we evolved the ribozyme for efficient use of 6-thio guanosine triphosphate (6sGTP). 6sGTP never appeared in the evolutionary history of the ribozyme, therefore it was expected that mutations would appear at the NTP binding site, adapting to more efficient binding of 6sGTP. Indeed, the evolution identified three mutations that mediate 200-fold improved incorporation kinetics for 6sGTP. A >50-fold effect resulted from muta

SUBMITTER: Akoopie A 

PROVIDER: S-EPMC6237761 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature