[Comparative analysis of the structure of double-stranded RNA from killer strains of Saccharomyces cerevisiae]. / Sravnitel'nyi analiz stroeniia dvuspiral'nykh RNK killernykh shtammov Saccharomyces cerevisiae.

Double-stranded RNAs (M and L molecules) of two strains of the killer system Saccharomyces cerevisiae M437 (wild type) and ski-5 (superkiller mutant) were studied by means of electron microscopy and high resolution thermal melting. The M molecules of the ski-5 mutant were by 100 b.p. shorter than those of M437. L molecules were of the same length for both strains. Analysis of the differential melting curves of L molecules showed that L molecules differ significantly in their nucleotide sequences, whereas M molecules were practically identical. It was found that M molecules contained a long AU region: that of M molecules of M 437 was 170-180 b.p. long and contained almost no GC pairs, whereas the AU region of M molecules of the ski-5 mutant was three times shorter and contained GC pairs.

[Natural interferon inducers: double-stranded RNA of killer plasmids of Saccharomyces cerevisiae]. / Prirodnye induktory interferona: dvuspiral'naia RNK killernykh plazmid Saccharomyces cerevisiae.

Methods for isolation and purification of yeast double spiral RNA (dsRNA) are described. The most simple method includes reprecipitation of dsRNA in solutions of lithium chloride and its interphase distribution in the system of chloroform: isoamilic alcohol: water. Preparations with the content (w/w) of dsRNA from 30 to 90 per cent were obtained. They possess a high interferon-inducing activity and an antiviral effect on the experimental infection caused by the virus of mouse encephalomyocarditis.