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The taxonomic composition of bacteria associated with the Cephalotrix simula proboscis worm was studied and screening of the tetrodotoxin (TTX)-producing bacteria was carried out using confocal laser scanning microscopy and polyclonal antibodies. Bacterial isolates were identified using the 16S rRNA gene sequencing and phenotypic characteristics. A Bacillus species was found to be responsible for tetrodotoxin production in C. simula proboscis worms. Vibrio spp. predominated in the associated microflora (68.18% of the total number of isolates). Analysis of the sensitivity of 16 strains to antibiotics of various classes revealed multiple resistance to three or more antibiotics in all studied isolates. Poor growth of most of the isolates on all laboratory media was an indirect confirmation of the symbiotic relationships between the micro- and macroorganisms.

Exopolysaccharides (EPS) synthesized by Paenibacillus polymyxa 1465 in the course of batch cultivation were proven to contain neutral and acidic fractions. EPS are heterogeneous polysaccharides, represented by a complex of macromolecules with molecular mass of 7 x 10(4) to 2 x 10(6) Da. The acidic component was shown to be predominant in EPS preparations isolated from bacteria cultivated on glucose, which corresponds to a higher viscosity of EPS water solutions. The exoglycans were shown to contain glucose, mannose, galactose, and uronic acids. Polyclonal rabbit antibodies against the isolated P. polymyxa 1465 EPS preparations were used in a comparative immunodiffusion analysis of a number of P. polymyxa strains.

A moderately thermophilic, facultatively anaerobic bacterium capable of reducing Cr(VI) (strain SKC1) was isolated from municipal sewage. Based on the analysis of the 16S rRNA gene nucleotide sequence and DNA-DNA hybridization data, strain SKC1 was identified as a representative of the species Bacillus thermoamylovorans. B. thermoamylovorans SKC1 is capable of reducing chromate with L-arabinose as an electron donor with an optimum at 50 degrees C and neutral pH. The culture is able to reduce Cr(VI) at its initial concentration in the medium of up to 150 mg/l. In addition to chromate, strain SKC1 is capable of reducing selenite and tellurite, as well as soluble forms of Fe(III). It was shown that Cr(VI), Te(IV), and Se(IV) exert a bacteriostatic effect on strain SKC1, and the reduction of these anions performs the detoxification function. This is the first communication on the reduction of chromate, selenite, tellurite, and soluble Fe(III) species by a culture of thermophilic bacilli.

Abstract-Phylogenetic interrelation between 40 strains of the Bacillus cereus group has been established using BcREP fingerprinting. The PCR method has shown that the frequency of occurrence of the genes of cytotoxin K (cytK) and hemolysin II (hlyII) is 61% and 56%, respectively, and the gene of the hemolysin II regulator (hlyIIR) occurs together with hlyII. Comparison of the results of fingerprinting, PCR, and RFLP of the toxin genes showed that bacteria with the hlyII+ and cytK+ genotypes did not form separate clusters. However, microorganisms with the similar fingerprints were shown to have toxin genes of the same type. The proposed variant of RFLP analysis made it possible to clearly distinguish between the cytK1 and cytK2 genes. Twenty-three strains having the cytK genes carried no cytK1 dangerous for mammals. Additionally, the entire collection of microorganisms was tested for the ability to grow at 4 degrees C. This property was revealed for five strains, which should most likely be classified as B. weihenstephanensis. Two of the five psychrotolerant microorganisms carried the hemolysin II gene variant of the same type according to RFLP. None of the five strains had the cytK gene. These strains did not form close groups upon clustering by the applied method of Bc-REP fingerprints.

The influence of the cultivation conditions on Bacillus pumilus KMM 62 growth and effectiveness of the production of a subtilisin-like serine proteinase were investigated. Enzyme accumulation in the culture fluid reached the maximum value after 32 and 46-48 h of growth; it depends on the composition of the nutrient medium. The ratio of the concentrations of two main components of the medium, peptone and inorganic phosphate, which was optimal for enzyme biosynthesis was determined by multifactor experiments. Ammonium salts, when introduced as an additional nitrogen source, had different effects on the proteinase biosynthesis at different growth stages: they suppress enzyme production at the early stationary growth phase and stimulate the biosynthesis of the enzyme after 46-48 h of growth. Complex organic substrates (albumin, casein, hemoglobin, and gelatin) have a repressive effect on the biosynthesis of the enzyme. The effect of amino acids on culture growth and enzyme biosynthesis during the early and late stationary growth phase is different. Hydrophilic amino acids, glutamine, and glutamic acid exhibit the most pronounced repressive action on biosynthesis. The activity of different regulatory mechanisms for the synthesis of this proteinase is assumed at the early and late stationary stages of growth.

The biosynthesis of the subtilisin-like serine proteinase of Bacillus intermedius 3-19 by the recombinant strain Bacillus subtilis AJ73(pCS9) was found to be enhanced under salt stress conditions (growth in a medium containing 1 M NaCl and 0.25 M sodium citrate). In a recombinant strain of B. subtilis deficient in the regulatory proteins DegS and DegU, which control the synthesis of degradative enzymes, the expression of the proteinase gene was inhibited. In contrast, in the strain B. subtilis degU32 (Hy), which provides for the over-synthesis of proteins positively regulated by the DegS-DegU system, the biosynthesis of the subtilisin-like proteinase of B. intermedius 3-19 increased by 6-10 times. These data suggest that the DegS-DegU system is involved in the positive regulation of the expression of the subtilisin-like B. intermedius proteinase gene in recombinant B. subtilis strains.

The paper presents experimental data on the adsorption of bacterial cells on porous materials.

We investigated the influence of inhibitors of energy metabolism and ionophores on the growth and formation of metabolic products in alkaliphilic anaerobes characterized by various catabolism types. It was shown that blockage of oxidative phosphorylation by the addition of N,N'-dicyclohexylcarbodiimide (DCCD), an inhibitor of F1F0 ATP synthase, resulted in a complete arrest of the growth of the acetogenic bacterium Tindallia magadiensis with arginine as electron acceptor. In the presence of pyruvate, substrate-level phosphorylation occurred. The methylotrophic methanogenic archaebacterium Methanosalus zhilinae did not grow with DCCD and vanadate, an inhibitor of E1E2 ATPase, suggesting the presence of two ATPase types in this species. In the saccharolytic alkaliphiles Halonatronum, Amphibacillus tropicus, and Spirochaeta alkalica (which are characterized by different pH optima), the contribution of the H+ gradient to the energy metabolism and, presumably, to the maintenance of the intracellular pH level decreased with an increase in the degree of alkaliphily. Based on the data of an inhibitor assay using protonophores, monensin, and amiloride, we suggest that all of the bacteria tested depend on H+- and Na+-gradients. The Na+/H+ antiport appears to be a universal mechanism of regulating the intracellular pH level and the interaction between the Na+ and the H+ cycles in bacterial cells cultivated under alkaline conditions.

The microbial complexes of soil, the rhizosphere, and the rhizoplane of the apogeotropic (coralloid) roots of cycad plants were comparatively studied. The aseptically prepared homogenates of the surface-sterilized coralloid roots did not contain bacterial microsymbiont, indicating that it was absent in the root tissues. At the same time, associated bacteria belonging to different taxonomic groups were detected in increasing amounts in the cycad rhizoplane, rhizosphere, and the surrounding soil. The bacterial communities found in the cycad rhizoplane and the surrounding soil were dominated by bacteria from the genus Bacillus. The saprotrophic bacteria and fungi colonizing the cycad rhizosphere and rhizoplane were dominated by microorganisms capable of degrading the plant cell walls. The local degradation of the cell wall was actually observed on the micrographs of the thin sections of cycad roots in the form of channels, through which symbiotic cyanobacterial filaments can penetrate into the cortical parenchyma.

The saccharolytic anaerobic bacteria Halonatronum saccharophilum, Amphibacillus fermentum, and Amphibacillus tropicus produce formate the main fermentation product. In the alkaliphilic community, formate is used as the preferential substrate for sulfate reduction. To reveal the pathways of carbohydrate fermentation by these bacteria, the activity of the key enzymes of carbohydrate metabolism and their pH dependence was studied. It was established that H. saccharophilum utilized glucose by the fructose bisphosphate and hexose monophosphate pathways, and A. tropicus, by the fructose bisphosphate and Entner-Doudoroff pathways. The activity of the key enzymes of all three pathways of glucose metabolism was detected in Amphibacillus fermentum. According to the data obtained, the glucose catabolism in H. saccharophilum. A. fermentum, and A. tropicus mainly proceeds via the fructose bisphosphate pathway. The pH optima of the key enzymes of the glucose metabolism of the alkaliphiles are shifted to alkaline values. In A. tropicus, formate is formed from pyruvate under the action of pyruvate formate-lyase; and in the haloanaerobe H. saccharophilum, formate dehydrogenase is involved in formate metabolism.

The investigation of new secretory ribonucleases, the Bacillus intermedius binase II expressed in the recombinant B. subtilis strain 3922 and the native RNase Bsn of B. subtilis, showed that they are synthesized in the growth retardation phase, when inorganic phosphate is exhausted in the medium. The biosynthesis of these ribonucleases was found to be suppressed by the presence of inorganic phosphate in the medium and activated by small amounts of the transcriptional inhibitor actinomycin D. The cultivation media of the producing strains were optimized for the maximum production of the enzymes.

The effect of some components of cultivation medium on the growth of the streptomycin-resistant Bacillus intermedius strain 3-19 and on the production of glutamyl endopeptidase was investigated using factorial experimental design, which allowed the concentrations of peptone and inorganic phosphate to be optimized for the maximum production of the enzyme. Experiments with different peptones and casamino acids showed that the enzyme production is maximum with peptone 3 of plant origin. The addition of casamino acids or amino acids to the peptone-containing cultivation medium inhibited the production of glutamyl endopeptidase.

Azobenzene exerted no significant effect on the dynamics and the species composition of the saprophytic soil bacterial complex, which remained almost the same as in the control and was characterized by the predominance of Curtobacterium sp., Arthrobacter globiformis, and Bacillus megaterium in all stages of succession. Some heterotrophic bacteria were found to be able to accumulate azobenzene. Bac. cereus and Bac. polymyxa degraded azobenzene during their cultivation in nutrient media.

The moderately thermophilic acidophilic bacteria Sulfobacillus thermosulfidooxidans, strain 1269, S. thermosulfidooxidans subsp. "asporogenes," strain 41, and the thermotolerant strain S. thermosulfidooxidans subsp. "thermotolerans" K1 prefer mixotrophic growth conditions (the concomitant presence of ferrous iron, thiosulfate, and organic compounds in the medium). In heterotrophic and autotrophic growth conditions, these sulfobacilli can grow over only a few culture transfers. In cell-free extracts of these sulfobacilli, key enzymes of the Embden-Meyerhof-Parnas, pentose-phosphate, and Entner-Doudoroff pathways were found. The role of a particular pathway depended on the cultivation conditions. All of the enzymes assayed were most active under mixotrophic conditions in the presence of Fe2+ and glucose, suggesting the operation of all of the three major pathways of carbohydrate metabolism under these conditions. However, the operation of the Entner-Doudoroff pathway in strain 41 was restricted under mixotrophic conditions. After the first culture transfer from mixotrophic to heterotrophic conditions, the utilization of glucose occurred only via the Embden-Meyerhof-Parnas and Entner-Doudoroff pathways. After the first culture transfer from mixotrophic to autotrophic conditions, the activity of carbohydrate metabolism enzymes decreased in all of the strains studied; in strain K1, only the glycolytic pathway remained operative. The high activity of fructose-bisphosphate aldolase, remaining in strain 41 cells under these conditions, suggests the involvement of this enzyme in the reactions of the Calvin cycle or of gluconeogenesis.

Two lectins (LI and LII) stripped from the surface of Bacillus polymyxa 1460 cells were found to possess proteolytic activity, which was associated with their hemagglutinating activity. The inhibition of the hemagglutinating activity of lectins by specific carbohydrate haptens changed their enzyme activities. The inhibition of hemagglutinating activity by glucuronic acid or fructose 1,6-diphosphate decreased the proteolytic activities of both lectins, whereas the blocking of this activity with D-glucosamine or D-galactosamine increased the proteolytic activity of LII. The molecules of the B. polymyxa lectins are suggested to contain two active centers responsible for hemagglutinating and proteolytic activities.

A phylogenetic tree was constructed on the basis of the amino acid sequences of the known cyclodextrin glucanotransferases (CDGTs), including those deduced from the nucleotide sequences of Bacillus sp. strain 6.6.3 and Paenibacillus macerans IB-7 genes encoding alpha- and beta-CDGTs. The tree clearly demonstrates the existence of distinct phylogenetic groups of CDGT-producing microorganisms and the divergence of the alpha-, beta-, and gamma-CDGT produced by microorganisms from the genera Bacillus, Paenibacillus, Brevibacillus, and Thermoanaerobacter from a common ancestor, whereas the CDGT of Klebsiella pneumoniae is independent and results from the convergence of different ancestors. The degree of homology of the leader peptide sequences of CDGTs may serve as a criterion of intraspecies relatedness between CDGT-producing microorganisms.

The taxonomic composition of denitrifying bacteria in soddy podzolic soil was studied by the succession analysis method. This method revealed a significant variation in the taxonomic composition of denitrifying microorganisms in the course of succession. In contrast to succession analysis, the single microbiological analysis of soil samples reflected only the late stage of succession and thus led to an underestimation of the major members of succession. Myxobacteria were found to be the most active denitrifiers at the early stages of succession, whereas bacilli dominated at its late stages. The bacilli were represented by three facultatively anaerobic species, Bacillus cereus, Bac. circulans, and Bac. polymyxa.

The biosynthesis of extracellular alkaline phosphatase in the streptomycin-resistant strains Bacillus intermedius S3-19 and S7 in the presence in the medium of 5'-nucleoside monophosphates and different sources of carbon--glucose, sodium pyruvate, sodium lactate, or glycerol--was studied. It was established that, in the presence of mononucleotides, the content of extracellular alkaline phosphatase in both strains increased; the maximal effect was caused by 5'-AMP at a concentration of 20 micrograms/ml. In medium with a low orthophosphate content, where active biosynthesis of alkaline phosphatase occurred, 1% glucose and 0.5% pyruvate stimulated this process 2.5-4 times, and 2% sodium lactate and sodium pyruvate, on the contrary, inhibited it by 20-40%. Analysis of the dynamics of growth and accumulation of extracellular phosphatase in the presence of different sources of carbon in the medium gives evidence of an interrelationship between the biosynthesis of alkaline phosphatase and carbon metabolism in Bacillus intermedius.

The distribution and population density of aerobic hydrocarbon-oxidizing bacteria in the high-temperature oil fields of Western Siberia, Kazakhstan, and China were studied. Seven strains of aerobic thermophilic spore-forming bacteria were isolated from the oil fields and studied by microbiological and molecular biological methods. Based on the 16S rRNA gene sequences, phenotypic characteristics, and the results of DNA-DNA hybridization, the taxonomic affiliation of the isolates was tentatively established. The strains were assigned to the first and fifth subgroups of the genus Bacillus on the phylogenetic branch of the gram-positive bacteria. Strains B and 421 were classified as B. licheniformis. Strains X and U, located between B. stearothermophilus and B. thermocatenulatus on the phylogenetic tree, and strains K, Sam, and 34, related but not identical to B. thermodenitrificans and B. thermoleovorans, undoubtedly represent two new species. Phylogenetically and metabolically related representatives of thermophilic bacilli were found to occur in geographically distant oil fields.

An ability to synthesize and accumulate in the growth medium for extracellular amino acids of 108 strains of 13 aerobic sporeforming bacteria species at deep cultivation on the simple synthetic glucose-mineral liquid nutrient medium optimized for the representatives of this genus. Has been studied the bacillus strains studied in the present conditions synthesize 19 amino acids and 2 amino carbons in different quantities and combinations. Amino acids being synthesized the most and least by these microorganisms have been determined in quantitative expression. Extracellular amino acid accumulation was proved to be a strain property not of genus. In general, the genus studied was evaluated as active one in amino acid production. The most active strains may present an interest as initials for further selective obtaining of producers of separate amino acids. The outlook for aerobic bacilli strains having marked amino-synthesizing properties and complex of other biological activities is being discussed for construction of medicinal and prophylactic of live microbial culture preparations.

The content of lipids was studied in the gramicidin producing variants of Bacillus brevis var. G.-B. in the process of submerged cultivation. The greatest accumulation of lipids preceded the highest content of gramicidin C in the producing cells. The interrelation between the synthesis of lipids and that of gramicidin C is discussed.

The respiration rate of 25 studied oligonitrophilous strains belonging to various genera and species of bacteria varied within wide limits depending on their taxonomy, conditions of cultivation, substrates, and other factors. No strict correlation was established between the respiration rate and the activity of nitrogen fixation. One of the typical properties of oligonitrophilous bacteria is a high rate of endogeneous respiration --50% and more of the respiration rate during assimilation of exogeneous substrates. The level of oxidative metabolism of oligonitrophilous bacteria was found to be higher on media containing bound nitrogen than on media without nitrogen.

The maximum growth rate of thermophilic bacteria was found in the exponential growth phase during 2 to 3 hours, and the metabolism was aerobic. In the linear growth phase, the substrate (glucose) was metabolized both by the aerobic and anaerobic pathways during the cultivation of the thermophilic bacteria with shaking; this was confirmed by increasing values of the respiratory quotient and by the evolution of volatile acids. The mesophilic bacteria oxidized the substrate by the aerobic pathway under the same conditions of cultivation, both during the exponential and linear growth phases, and had the stable value of the respiratory quotient. The economic coefficient was lower in the thermophilic microorganisms (bacteria and thermotolerant yeasts) than in the mesophilic cultures.

Microorganisms destroying nonionogenic surfactants (NS) were selected. The isolated cultures were assigned to the genera Pseudomonas and Bacillus. Biodestruction of 19 NS was studied in Erlenmeyer flasks with shaking and in the course of continuous cultivation. The rate of destruction was shown to depend on the chemical structure of a substance: block-copolymers of ethylene and propylene oxides were more resistant to the action of microorganisms. The results indicate that sewage waters containing NS (at an initial concentration of 50 to 500 mg/l) can be purified on local installations using microbial cultures or their complexes.

The synthesis of the antibiotic polymyxin M was studied under the conditions of batch and continuous cultivation of Bacillus polymyxa var. Ross whose growth was limited with glucose, phosphate and ammonium nitrogen. Polymyxin M was synthesized when the culture growth decelerated as a result of its limitation with the above compounds. Different amounts of the antibiotic were synthesized depending on the type of a limiting factor. The highest productiveness was found in the case of glucose limitation. The optimal conditions for polymyxin M synthesis were established under the conditions of one-step continuous cultivation.

The respiration rate of spore suspensions of Bacillus anthracoides 96 was assayed by mass spectrometry employing a hermetically sealed reaction vessel constructed for this purpose. The rate of respiration was found to depend on the method of preparing suspensions, the duration of their storage at +4 degrees C, the physiological state of spores, and the action of a disinfectant containing chlorine on them.

The growth, development and changes in the chemical composition of Bacillus popilliae cells were studied in the course of their growth on a liquid chemically defined medium containing casein hydrolysate, complex vitamin mixtures and glucose. Growth of the culture on this medium was accompanied with diauxia which could be registered by changes in the rate of growth and synthesis of the main cellular polymers (DNA, RNA, protein, phospholipids). The rate of protein synthesis correlated with the specific growth rate which was maximal when the reserve substances of the cells or the compounds of partly digested biomass were used. The rate of protein synthesis in the experiment depended mainly on the protein synthesizing activity of RNA rather than on its content in the cells. The low rates of growth and protein synthesis, which suggest that the growth of the culture is being interested with in the course of utilization of the components of the nutrient medium, may account for the absence of spore formation by this strain on the medium used.

Gramicidin S is tritiated in Bacillus brevis G.-B. intact cells by activated tritium atoms (which is indicative of its surface localisation). The cell wall protein is tritiated very weakly, which shows that it is screened, apparently, by gramicidin adsorbed on its surface. The cell wall protein is not a glycoprotein and its interaction with exogenous gramicidin S causes cell aggregation. As follows from the Rf value after the chromatographic separation of B. brevis lipids, the reaction of staining, and the data of H-NMR spectroscopy for the fraction of phospholipids, the main membrane phospholipid is an anionic acetylated phosphatidyl ethanolamine.

The effect of changes in the kinetics of growth on gramicidin S biosynthesis by Bacillus brevis var. G.-B. was studied. The synthesis of gramicidin S is induced when the specific growth rate decreases, whatever is the factor causing this decrease. As was found experimentally, only cells of a certain age can synthesize gramicidin S.

The dynamics of varying ATP concentration was studied in the cells of the thermophilic strain of Bacillus brevis 224 synthesizing a neutral exoprotease. Some irregularities during the primary and secondary growth of the culture corresponded to the changes in the amount of ATP. A sharp decrease (by a factor of ca. 100) in the level of ATP pool was detected in the bacterial cells after 2.5 hours of their exponential growth; their growth ceased and the synthesis of protease was depressed. A decrease in the rate of the enzyme synthesis coincides with an increase in the concentration of ATP in the cells.

A poly(A)+RNA fraction was isolated from the overall RNA of Bacillus intermedius using chromatography on poly(U) Sepharose and was shown to be electrophoretically heterogeneous. The presence of a polyadenylate segment was confirmed by hybridization with polyuridine. The biological activity of the poly(A)+RNA was proved by the translation in Xenopus laevis oocytes. The dynamics of poly(A)+RNA synthesis was studied in the course of B. intermedius growth and the content of poly(A)+RNA was assayed in the cells grown in different media.

Amino acids and proteins were found to produce different effect on the synthesis of bacitracin and exoprotease by Bacillus licheniformis 28 KA depending on the age of the cells. The enzyme synthesis was induced by amino acids and proteins only in the cells at the exponential growth phase. No correlation could be established between the antibiotic and proteolytic activities. The optimal protease synthesis was found in a medium with isoleucine whereas the antibiotic synthesis was optimal in a medium containing no amino acids.

Two membrane antigens were found by cross immunoelectrophoresis in the cell walls of Bacillus brevis var. G.-B., R form, which started to synthesize gramicidin S (20 mg per 1 ml of cultural broth). The cell wall contained no membrane components in cells at the beginning of the logarithmic growth phase. The protein with a molecular mass of 100 kDa is a component of the cell wall outer layer. The protein is not digested by trypsin or pronase when it comprises the cell walls of cells synthesizing gramicidin S. In the preparation of isolated cell walls, this protein becomes susceptible to the action of the above proteases only when the peptidoglycan layer is broken down by lysozyme. Electron microscopy of cells treated with proteases and shadowed with a metal revealed that many cells lacked the cytoplasm. Therefore, the outer layer of B. brevis R cell wall contains small regions susceptible to the action of protease along with regions composed of the 100 kDa protein and resistant to these enzymes. It is possible that the small regions contain membrane components.

Five strains of sporeforming bacteria were isolated from sewage of capron industry and their morphological, cultural, as well as physiological and biochemical properties were investigated. Four strains were identified as Bacillus subtilis and one as Bacillus pumilus. The cultures were able to grow in mineral medium with caprolactam as a source of carbon and nitrogen. The influence of growth conditions on the rate of caprolactam decomposition in synthetic medium was studied.

Soil sporeforming denitrifying bacteria, Bacillus filaris and Bacillus polymyxa, differ by their cultural-morphological and physiological characteristics, but are similar in the chemistry of dissimilating nitrate reduction. Two processes occur simultaneously: denitrification yielding gaseous nitrogen forms, and nitrate respiration upon which nitrates are reduced to ammonia. The ratio between the two depends on physico-chemical conditions of the environment. The chemistry of dissimilating nitrate reduction by sporeforming bacteria differs therefore from nitrate transformation by other denitrifying microorganisms: Pseudomonas, Micrococcus, Rhizobium, Achromobacter, which, according to the published evidence, are capable only of denitrification.

Qualitative composition of the population of Bacillus brevis was found to depend on growth conditions. Under optimum aeration conditions for growth of the culture and biosynthesis of gramicidin C, the population was polymorphous and contained cells and spores of different age. No spores and prospores were found in the culture in conditions of weak and strong aeration. The population consisted only of young, intensively coloured cells with homogeneous or weakly differentiated content in conditions of strong aeration. Cells with the differentiated protoplasm containing large, distinctly seen vacuoles were found in conditions of weak aeration. Gramicidin C was synthesized by young cells with basophilic homogeneous or weakly differentiated protoplasm.

The type of intensification affects the distribution of bacteria involved in turnover of nitrogen in pond water. Green fertilizers (reed) stimulate the number of nitrogen-fixing bacteria, and the number and activity of nitrifying bacteria, to a higher degree than nitrogen and phosphorus fertilizers. Reed is recommended as the main means for intensification of spawning ponds of the Astrakhan Region.

Oxygen assimilation by the spore suspensions of Bacillus anthracoides under sterile conditions was continuously registered by means of a modified mass-spectrometry technique using an original reaction vessel. The sensitivity of the technique is 2.10(-2) mcl O2 per 1 mg of dry biomass per hour. The technique made it possible to determine the level of endogenous respiration activity in the spore suspensions of Bacillus anthracoides.

Conditions for continuous cultivation of the thermophilic strain of Bacillus brevis prodlcing protease are substantiated. The culture was cultivated in order to obtain proteolytic enzymes taking into consideration data concerning kinetics of the bacterial growth and enzyme synthesis, as well as results of studying accumulation of the pool of mRNA specific of protease synthesis, The rates of dilution and flow (approximately 0.4 hr-1) have been found which provide a high specific productivity of the culture.

The sublethal dose of calcium hypochlorite (CH) of 0.2--0.3 mg/ml active chlorine did not cause, after 5 min, morphological changes in the spores of Bacillus anthracoides which could be detected by phase contrast microscopy, or a decrease in the content of dipicolinic acid (DPA) in the spores. Further cultivation of the spores treated with the sublethal dose of CH om MPA resulted in a delay of changes which were typical of normal germination process (swelling, loss of light refraction, decrease in DPA content). The action of the lethal dose of CH (0.2--0.3 mg/ml active chlorine during 1.5 hr or 5.6 mg/ml active chlorine during 1 hr) causes a decrease in light refraction, changes in the dimensions of spores, and a decrease in the content of DPA in the spores by a factor of 4--5. A sharp decrease in the content of DPA in the spores may characterize not only their germination but also their death caused by lethal doses of the chlorine containing disinfectant.

Phospholipid fractions were isolated from the cells of Bacillus brevis var. G.-B. variants, some, of which produced gramicidin S and some did not. As was found by thin layer chromatography, phosphatidyl ethanolamine predominated in the fraction of phospholipids. Interaction of the isolated phospholipids with gramicidin S in vitro resulted in a loss of the antibiotic activity. Presumably, formation of a complex between the polypeptide and phospholipids may decrease the actual concentration of gramicidin S in cells producing the antibiotic.

The purpose of this work was to study growth of Bacillus polymyxa 153, biosynthesis of polymyxin by it, the formation of spores, and the fine structure of the cells. The antibiotic content was low in the cells and in the cultural broth during the first hours of growth and sharply increased later under the conditions of the medium ensuring the "vegetative" type of cultural growth. The cell wall reorganized, a periplasmic space appeared, and the membranous and mesosomal apparatus became more complicated in the cells actively synthesizing the antibiotic. The antibiotic content was higher in the cells belonging to the "spore" type of growth at the beginning of mass spore formation. Further cell development involved endospore differentiation; a complicated membranous apparatus did not appear, and biosynthesis of the antibiotic stopped.

The paper presents new data concerning the mechanism of microbiological dissolution of gold. The sign of charges on gold-protein complexes was determined by paper electrophoresis. Anion complexes were found to prevail. Free amino groups participate in formation of complexes between gold and amino acids in alkaline medium, and functional groups of amino acid residues in polypeptide groups are involved in formation of complexes with proteins. Formation of complexes between gold and these compounds seems to be due to the Au--N bond.