[Cytomorphological and cultural characteristics of tylosin-producing strains with different antibiotic activity].

Cytomorphological and cultural characteristics of highly and low active collection strains of Streptomyces fradiae producing tylosin were studied. The strains were grown on agarized and liquid media. It was shown that unlike the low active strain, the highly active one was less sporogenic, the difference being more pronounced when tylosin was added to the agarized medium.

[Membrane potential levels in Acetabularia cells].

The membrane potential (MP) of A. mediterranea cell is shown to have two stationary levels RP==--170 mv and EP=--80 mV and an unstable one -- level of action potential peaks -- EP=--60 mV. The following transitions between the MP levels are possible: RP leads to EP' equilibrium EP leads to RP.

[Electric parameters and equivalent schematics for Acetabularia cells].

Was measured values of electric resistance (R) and capacity (C) of A. mediterranea cell at different levels of the membrane potential (MP). At the level -170 mV, RRP=4,3 KOm-cm2, at the level -80 mV REP=1,4 KOm-cm2.