[Relationship between the synthesis of a new stress response component and bacterial cell metabolism].

Various stress factors (incubation with redox-cycling agents, ozonization, heat shock) that induced accumulation of 2-C-methyl-D-erythritol-2,4-cyclopyrophosphate (MEC) were also shown to induce various alterations of the phospholipid composition in three microbial species: Corynebacterium ammoniagenes, Micrococcus luteus, and Staphylococcus aureus. The influence of adding 10 carbohydrates to the growth medium on MEC accumulation by C. ammoniagenes cells was tested.

[Stability of a new product of oxidative stress in bacterial cells].

Data on 32P-label incorporation with subsequent addition of non-radiolabelled o-phosphate suggest that the new phosphorus compound, 2-C-methyl-D-erythritol-2,4-cyclopyrophosphate (MEC), accumulated in the cells of some bacterial species in response to oxidative stress does not rapidly exchange phosphorus with external o-phosphate 3 hours after the introduction of its synthesis inducers into the Corynebacterium ammoniagenes culture. The accumulated MEC is retained in the cells despite the action of the cell wall synthesis inhibitor, chloramphenicol, or the energetic poisons, KCN and iodoacetate and also under anaerobic conditions. It has been shown that incubation of the cell-free lysate of a non-induced culture, Micrococcus luteus, with MEC does not result in MEC hydrolysis; therefore, MEC accumulation after the redox-mediator addition is hardly due to the hydrolase inactivation but, rather, is due to the activation of the MEC-synthesizing enzyme.

[Effect of antiseptics and redox-cycling agents on Corynebacterium ammoniagenes and related microorganisms in relation to synthesis of a new macroergic compound].

Sublethal concentration of the antiseptic composition Desoxon-1 was shown to provoke in cells of Corinebacterium ammoniagenes in a liquid medium the biosynthesis and accumulation of a novel macroergic 2-methylbutane-1,2,3,4-tetraol-2,4-cyclopyrophosphate. This substance is also synthesized when C. ammoniagenes is cultivated in a solid agar medium supplemented with benzylviologen.

[Membrane potential in Escherichia coli bacteria subjected to the action of low temperature freezing and blood serum complement].

The action of a blood serum complement on Escherichia coli cells or their freezing does not cause cell destruction visible in the electron microscope, but the permeability barrier is disordered and exogenous substrates can penetrate into the cell. When these exogenous respiration substrates are oxidised, the energy-dependent uptake of phenyl dicarboundecarborane (PCB-), a lipophilic anion and an indicator of the membrane potential, is observed. Apparently, the uptake of PCB- is associated with the generation of local membrane potentials when the permeability barrier of cells is damaged.