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Replacement of 2'-Deoxycytidine by 2'-Deoxycytidine Analogues in the E. coli Genome.

ABSTRACT: Several modified bases have been observed in the genomic DNA of bacteriophages, prokaryotes, and eukaryotes that play a role in restriction systems and/or epigenetic regulation. In our efforts to understand the consequences of replacing a large fraction of a canonical nucleoside with a modified nucleoside, we previously replaced around 75% of thymidine (T) with 5'-hydroxymethyl-2'-deoxyuridine (5hmU) in the Escherichia coli genome. In this study, we engineered the pyrimidine nucleotide biosynthetic pathway using T4 bacteriophage genes to achieve approximately 63% replacement of 2'-deoxycytidine (dC) with 5-hydroxymethyl-2'-deoxycytidine (5hmC) in the E. coli genome and approximately 71% replacement in plasmids. We further engineered the glucose metabolic pathway to transform the 5hmC into glucosyl-5-hydroxymethyl-2'-deoxycytidine (5-gmC) and achieved 20% 5-gmC in the genome and 45% 5-gmC in plasmid DNA.

SUBMITTER: Mehta AP

PROVIDER: S-EPMC5134732 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Replacement of 2'-Deoxycytidine by 2'-Deoxycytidine Analogues in the E. coli Genome.

Mehta Angad P AP Li Han H Reed Sean A SA Supekova Lubica L Javahishvili Tsotne T Schultz Peter G PG

Journal of the American Chemical Society 20161020 43

Several modified bases have been observed in the genomic DNA of bacteriophages, prokaryotes, and eukaryotes that play a role in restriction systems and/or epigenetic regulation. In our efforts to understand the consequences of replacing a large fraction of a canonical nucleoside with a modified nucleoside, we previously replaced around 75% of thymidine (T) with 5'-hydroxymethyl-2'-deoxyuridine (5hmU) in the Escherichia coli genome. In this study, we engineered the pyrimidine nucleotide biosynthe ...[more]

PMID: 27762133

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