| The purine and pyrimidine bases in cells are linked to carbohydrate and in this form are termed, nucleosides. |
| Conversely, the reaction of purine and pyrimidine nucleobases with alkylating and oxidizing agents generally results in site-specific cleavage. |
| The transcription of the operon is coordinately repressed in the presence of excess pyrimidine nucleotides. |
| These enzymes normally catalyze the formation of uridine monophosphate from orotic acid during pyrimidine synthesis. |
| Our analyses also suggest that the utilization of products of de novo pyrimidine biosynthesis may differ between different cell types. |
| A nucleotide is a combination of a ribose or deoxyribose sugar, a purine or pyrimidine base, and a phosphate group. |
