The Structures and Properties of Poly-5-methylcytidylic Acid

✍ Scribed by Myron M. Warshaw; Ralph Noe

• Publisher: Wiley (John Wiley & Sons)
• Year: 1972
• Tongue: English
• Weight: 1006 KB
• Volume: 11
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1972.360110611

✦ Synopsis

The optical rotatory dispersion properties of poly SMeC, poly diMeC, and 5MeCMP-(5') in O.1M Na+ have been studied at various pH values and temperatures. Poly 5MeC and poly diMeC have optical properties which are similar to those for poly C; however, poly 5MeC has a biphasic melting profile in the pH range from 3.8 to 5.4 similar to that observed for poly 51C. Using titration, ionic strength, and pH dependence measurements, the data for poly 5MeC are interpreted in terms of the following scheme a t pH 4.0 and 0.1 ionic strength: triple-strand helix d double-strand helii single-strand coil.

The effect of the methyl group is discussed in terms of similar structural possibilities for other polymers of cytidylic acid.

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Support for this scheme is discussed.

* This work was supported in part by an NSF Grant GB8569 (to M.M.W.