| Autor: |
E A, Lesnik, I M, Kochkina, A S, Tikhonenko, Ia M, Varshavskiĭ |
| Rok vydání: |
1980 |
| Předmět: |
|
| Zdroj: |
Molekuliarnaia biologiia. 14(4) |
| ISSN: |
0026-8984 |
| Popis: |
The electron microscopic data and the CD spectra of poly(G) have shown that the transition of a freeze-dried preparation of poly(G) from a "metastable" to a "stable" form is the transition of the four-stranded poly(G) from the globular form to the linear one. The observed phenomenon of the formation of long four-stranded poly(G) fibers (4--5 nm in diameter and 200-2000 nm in length) is suggested to be a result of a joint of the initial poly(G) molecules (50--80 nm in length) due to noncovalent binding ("sticking") of their free one-, double- or three-stranded ends. This phenomenon has permitted us not only to compare the thickness of low molecular weight poly (G) preparations under different conditions but to observe directly the existence of a large number of double-stranded (2--3 nm in diameter) regions ("defects") in four -stranded poly(G) fibers. The data obtained have shown that under certain conditions (high temperature, low pH, etc.) the four-stranded poly(G) fibers break down with the formation of two-stranded poly(G) fibers whose hydrogen bond systems depend on the conditions of their formation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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