[Increase in the yield of recombinant proteins in Saccharomyces cerevisiae yeasts as a result of optimizing their culture conditions]. / Povyshenie vykhoda rekombinantnykh belkov v drozhzhakh Saccharomyces cerevisiae v rezul'tate optimizatsii uslovii ikh kul'tivirovaniia.

The optimal one-stage scheme of the cultivation of the recombinant yeast strains was developed. In these strains, the expression of the foreign gene is induced at the medium depletion by phosphorus. The scheme was tested for the producers of human interleukin-2 and bovine gamma-interferon. In all the strains, the yield of cell biomass and the production of the foreign proteins increased as compared to the standard two-stage cultivation. The use of the developed scheme resulted in the threefold increase in the yield of the target proteins and in the productivity of the biotechnological process.

["Killer" plasmid in natural strains of Saccharomyces]. / Plazmida "killer" u prirodnykh shtammov Saccharomyces.

Double stranded RNA's of thirteen wine strains of Saccharomyces belonging to different species and exhibiting killing activity were studied. Two strains of Oxford genetic stocks were used for control. All these strains have four different spectra of killer activity and contain two double stranded RNAs, L and M. All strains regardless of the type of killer activity have the same electrophoretic mobility of L. The mobility of M varies in different strains but is not connected with the spectrum of killing activity. All strains can be cured by cycloheximide. Cured variants have no M. Certain cured strains contain small portions of double stranded RNAs with electrophoretical mobility faster than of M.