Studies on the bacteriophage MS2. XXIII. Fixation of the MS2 RNA acid structure by formaldehyde

✍ Scribed by H. Slegers; W. Fiers

• Publisher: Wiley (John Wiley & Sons)
• Year: 1973
• Tongue: English
• Weight: 468 KB
• Volume: 12
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1973.360120909

✦ Synopsis

Abstract

When MS2 RNA is heated at low p^H^ in the presence of formaldehyde, a fast‐sedimenting conformation is irreversibly formed. This species is homogeneous and stable at neutral p^H^. Its formation further requires Mg^++^ ions and low ionic strength. The most compact form sediments at 46S and is obtained after short reaction times at high temperature or after long reaction times at 35°C. Melting curves suggest that the specific acid conformation is not destabilized by the formaldehyde addition reaction. The p^H^ at which this acid conformation is formed depends on the MgC1~2~ concentration. At 10^−2^M MgCl~2~ the midpoint is p^H^ 5.3. Removal of more than half of the bound formaldehyde has no effect on the compactness of the molecule, although most of the original secondary structure has not yet re‐formed.