DNA templates containing a set of base modifications in the major groove (5-substituted pyrimidines or 7-substituted 7-deazapurines bearing H, methyl, vinyl, ethynyl or phenyl groups) were prepared by PCR using the corresponding base-modified 2'-deoxyribonucleoside triphosphates (dNTPs). The modified templates were used in an in vitro transcription assay using RNA polymerase from Bacillus subtilis and Escherichia coli Some modified nucleobases bearing smaller modifications (H, Me in 7-deazapurines) were perfectly tolerated by both enzymes, whereas bulky modifications (Ph at any nucleobase) and, surprisingly, uracil blocked transcription. Some middle-sized modifications (vinyl or ethynyl) were partly tolerated mostly by the E. colienzyme. In all cases where the transcription proceeded, full length RNA product with correct sequence was obtained indicating that the modifications of the template are not mutagenic and the inhibition is probably at the stage of initiation. The results are promising for the development of bioorthogonal reactions for artificial chemical switching of the transcription.

• MeSH
• Bacillus subtilis enzymologie   MeSH
• deoxyribonukleotidy biosyntéza   chemie   MeSH
• DNA řízené RNA-polymerasy metabolismus   MeSH
• DNA chemie   metabolismus   MeSH
• Escherichia coli enzymologie   MeSH
• genetická transkripce * MeSH
• genetické matrice MeSH
• konformace nukleové kyseliny MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• deoxyribonukleotidy MeSH
• DNA řízené RNA-polymerasy MeSH
• DNA MeSH