[Comparative study of the membrane protein composition of bacteria in the genus Bdellovibrio]. / Sravnitel'noe izuchenie belkovogo sostava membran bakterii roda Bdellovibrio.

The protein composition of membranes was studied in 17 Bdellovibrio strains by electrophoresis in polyacrylamide gel in the presence of sodium dodecyl sulfate. No similarity in the protein composition of membranes was found in the strains grown on cells of one and the same host. A dendrogram constructed basing on the similarity coefficients between the strains allowed to subdivide them into 3 groups according to the protein composition of their membranes. This correlated with the other phenotypic features and genotaxonomic data.

[Interrelationship of polyphosphate metabolism and levorin biosynthesis in Streptomyces levoris]. / O vzaimosviazi polifosfatnogo obmena s biosintezom levorina i Streptomyces levoris.

The effect of inorganic phosphate on biosynthesis of the polyene antibiotic levorin by Streptomyces levoris was studied. At phosphate concentration of 4.0 mM levorin biosynthesis is repressed by 90%, resulting in an increase of ATP and a condensed inorganic polyphosphates content in the producer cells. At phosphate concentration optimal for levorin production (0.04 mM) the level of intracellular ATP sharply falls by the beginning of the steady-state phase of the producer growth and that of polyphosphates decreases 3-6-fold. The inorganic phosphate exerts different effects on polyphosphate metabolism enzymes, such as polyphosphate: D-glucose-6-phosphotransferase, polyphosphate phosphohydrolase, tripolyphosphate phosphohydrolase, pyrophosphate phosphohydrolase, alkaline and acid phosphatase. The strongest effect of phosphate excess is observed in the case of polyphosphate: D-glucose-6-phosphotransferase, whose activity decreases 2-5-fold. The activity of this enzyme was shown to be correlated with the antibiotic accumulation. The data obtained are indicative of interrelationship between the polyphosphate metabolism and levorin biosynthesis.

Protein composition of Bdellovibrio bacteriovorus and Escherichia coli membranes during their interaction.

A comparative study of membrane proteins of Bdellovibrio bacteriovorus and host-bacteria Escherichia coli was performed by polyacrylamide gel electrophoresis in presence of sodium dodecyl sulphate. Infection of E. coli cells by bdellovibrions resulted in the loss of some high-molecular proteins and appearance of new ones in the host-bacteria membranes. The possible role of parasite proteases in degradation of host-bacteria membrane proteins is discussed.

[Possible participation of pyrophosphate in ADP and ATP biosyntheses from exogenous adenine by a culture of Corynebacterium species VSTI-301]. / O vozmozhnosti uchastiia prirofosfata v biocinteze ADP i ATP iz ekzogennogo adenina kul'turoi Corynebacterium species BCTI-301.

The autolyzing culture of Corynebacterium species VSTI-301 producing the synthesis of ATP from exogenous adenine was found to contain enzyme systems, which phosphorylate AMP into ADP and ADP into ATP in the presence of pyrophosphate. The optimal conditions for manifestation of activities of both systems in a cell-free extract were determined. One of the enzymes, i. e. pyrophosphate : ADP phosphotransferase, was isolated and purified 76-fold.

[Carbohydrate metabolic characteristics of coryneform bacteria]. / Osobennosti metabolizma uglevodov u korinepodobnykh bakterii.

The peculiarities of glucose metabolism were studied in typical representatives of coryneform bacteria, and its relation to inorganic polyphosphate metabolism was shown. The activity of the first two enzymes in the pentose pathway was found to be low. The key enzymes of glycolysis were detected, viz. fructose-1,6-diphosphate aldolase and 3-phosphoglyceraldehyde dehydrogenase. The second enzyme was more active in Nocardia sp. B-293 similar in its properties to Nocardia erythropolis as compared to the enzymes of the pentose shunt. The existence of polyphosphate glucokinase more active than ATP-dependent hexokinase is indicative of inorganic polyphosphates being involved in the metabolism of the above microorganisms.

Detection of polyphosphates and enzymes of polyphosphate metabolism in Bdellovibrio bacteriovorus.

Bdellovibrio bacteriovorus cells, parasitizing in E. coli, contain a considerable amount of inorganic polyphosphates, 55% of the total pool of which is due to the most polymeric acid-insoluble polyphosphates. B. bacteriovorus contains enzymes participating both in the synthesis and consumption of polyphosphates, i.e. 1,3-diphosphoglycerate: polyphosphate phosphotransferase, polyphosphate glucokinase, polyphosphatase, tripolyphosphatase, pyrophosphatase, acid and alkaline phosphatases. The possible role of high-molecular polyphosphates in the vital activity of the bacterial parasite B. bacteriovorus is discussed.

[Possible role of high molecular weight polyphosphates in ATP synthesis from exogenous adenine by the culture of Corynebacterium sp., strain VSTI-301]. / Izuchenie vozmozhnoi roli vysokomolekuliarnykh polifosfatov v sinteze ATP iz ekzogennogo adenina kul'turoi Corynebacterium Species, shtamm VSTI-301.

An addition of exogenous adenine to an autolysing 72-hour culture of Corynebacterium sp., strain BSTI-301 results in accumulation of as much as 0,6--1,0 mp of ATP per 1 ml of medium. Extracellular ATP accumulation under such conditions is coupled with a considerable decrease of the intracellular content of 5'-phosphoribosyl-1-pyrophosphate, orthophosphate, pyrophosphate and two fractions of high-polymeric polyphosphates PPh3 and PPh4, as compared to the control. The activity of pyrophosphate phosphohydrolase (EC 3.6.1.1) and polyphosphate phosphohydrolase (EC 3.6.1.11) is thereby considerably decreased in the cells growing on exogenous adenine, while the activity of ADP-phosphotransferase (EC 2.7.4.1) is increased 2-fold. It was found that in experiments with 14C-adenine the intracellular content of both ATP and ADP remains unchanged despite a considerable accumulation of extracellular ATP in Corynebacterium sp., strain BSTI-301 cells.

Some problems of the ecology and taxonomy of marine microvibrios.

The bactericidal effect of water from the Indian and Pacific oceans and Caspian and White seas on Escherichia coli was studied. It is shown that a decrease in the viability of E. coli cells is accompanied by the appearance and active multiplication of small bacteria of a vibrioid form. Two strains of such bacteria were isolated from a suspension of E. coli in seawater and purified from membranes of the substrate organism by the method of centrifugation in a Ficoll gradient. The marine bacteria of vibrioid form are very similar to the bacterial parasite Bdellovibrio bacteriovorus in fatty acid composition and characteristic cycle of development.

[Relationship between the content of some fractions of high molecular weight polyphosphates and total nucleic acids upon dehydration of the yeast Saccharomyces cerevisiae]. / O vzaimosviazi soderzhaniia nekotorykh fraktsii bysokomolekuliarnykh polifosfatov i summarnogo kolichestva nukleinovykh kislot pri obezvozhnvanii drozhzhei Saccharomyces cerevisiae.

Essential redistribution of various polyphosphate fractions was shown during dehydration and subsequent reactivation of Saccharomyces cerevisiae 14. Dehydration no matter what method was used, was followed by an increase in the content of acid soluble polyphosphates (fraction Poly P1) and a decrease of that of salt soluble polyphosphates (fraction Poly P2). Reactivation of dehydrated yeast was, on the contrary, accompanied by a decrease in the PP 1 and an increase in the Poly P2 content. A direct correlation between the Poly P2 fraction and total nucleic acids was demonstrated under various conditions of dehydration and subsequent reactivation. An inverse correlation between the content of the Poly P2, fraction and nucleic acids, on the one hand, and that of the Poly P1 fraction, on the other, was observed. Study of activities of polyphosphatases, tripolyphosphatase, pyrophosphatase and ATPase in dehydrated yeast showed values similar to those in original cells.

Role of ATP-glucokinase and polyphosphate glucokinase in Streptomyces aureofaciens.

The activity of ATP-glucokinase and of polyphosphate glucokinase was examined during growth of the actinomycete Streptomyces aureofaciens 8425 under conditions of intense chlortetracycline (CTC) synthesis. ATP-glucokinase was active in the strain only during the logarithmic phase of culture growth; the activity of polyphosphate glucokinase appears only at the end of the logarithmic phase of growth and rises in parallel with the rate of CTC biosynthesis in the stationary phase. During the rise of activity of polyphosphate glucokinase and of CTC biosynthesis the cells accumulate sugar phosphates, mainly glucose-6-phosphate. It appears that the biosynthesis of CTC in Streptomyces aureofaciens takes place at the expense of glycolysis, using up the high-energy phosphate of high-molecular polyphosphates.