title: Novel structure at 5'-ends of nascent DNA chains.
abstract: Because of their association with protein short nascent DNA chains in Escherichia coli can be separated from other cellular DNA by chromatography on hydroxylapatite. Protein-free DNA chains of less than 500 nucleotides in length are resistant to degradation from the 5'-end by alkaline phosphatase [orthophosphoric-monoester phosphohydrolase (alkaline optimum); EC 3.1.3.1] and spleen phosphodiesterase (oligonucleate 3'-nucleotidohydrolase; EC 3.1.4.18). In contrast, DNA chains containing more than 500 nucleotides are degradable. From these results we conclude that short nascent DNA chains are structurally modified at their 5'-ends. The nature of this structure and its possible functions are discussed.
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D004261:DNA Replication; D004269:DNA, Bacterial / Q000032:analysis* / Q000096:biosynthesis; D004285:Dogs; D008970:Molecular Weight; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D000469:Alkaline Phosphatase; D010727:Phosphoric Diester Hydrolases