Osmium-labeled Polynucleotides: Reaction of Osmium Tetraoxide, with Poly-1,N6-Ethenoadenylic Acid

✍ Scribed by Luigi G. Marzilli; Brian F. Hanson; Leilani Kapili; Seth D. Rose; Michael Beer

• Book ID: 102638258
• Publisher: Elsevier Science
• Year: 1978
• Weight: 281 KB
• Volume: 8
• Category: Article
• ISSN: 0006-3061
• DOI: 10.1016/0006-3061(78)80006-4

✦ Synopsis

Osmium tetraoxide, in the presence of ligands such as pyridine and bipyridine, adds across the etheno bridge of 1,N6-etheno-9-methyladenine and poly-1,N6-ethenoadenylic acid. The Os:P ratio in the labeled polynucleotide was approximately equal to 1 when bipyridine was used as the stabilizing ligand. A similar study with polycytidylic acid, which had been partially modified with chloroacetaldehyde so that some bases were converted to 3,N4-ethenocytosine, gave an OS:P ratio of approximately equal to 1.3. Calf-thymus DNA, in which the adenine and cytosine bases were modified by chloroacetaldehyde, gave an Os:P ratio of approximately equal to 1 after 24 h. These results suggest that 3,N4-ethenocytosine will add two Os labels.