The role of protonic and sodium potentials in the motility of E. coli and Bacillus FTU

The motility of Escherichia coli and of alkalo- and halotolerant Bacillus FTU has been studied. It is found that Bac. FTU motility (i) requires Na+, (ii) is resistant to the protonophorous uncoupler pentachlorophenol (PCP) if cells grow at high pH, and is sensitive to the uncouplers at neutral pH, (iii) is sensitized to the uncouplers with the addition of monensin, (iv) sensitive to amiloride and (v) can be supported by an artificially imposed Na+ gradient in the presence of uncoupler, cyanide and arsenate. On the other hand, E. coli motility (a) does not require Na+, (b) is always uncoupler-sensitive, (c) is amiloride-resistant, and (d) can be supported by an artificially-imposed gradient of H+, not Na+. It is concluded that the motilities of Bac. FTU and E. coli are due to the operation of the Na+ and the H+ motors, respectively. In Bac. FTU growing at alkaline pH, the Na+ motors are assumed to be energized by delta mu Na+ produced by the Na(+)-motive respiratory chain, and therefore delta mu H+ is not involved in the motility process. As to Bac. FTU growing in a neutral medium, delta mu Na+ is produced secondarily, via the Na+/H(+)-antiporter, i.e., at the expense of delta mu H+ formed by the H(+)-motive respiratory chain.

Characterization of .kappa.-carrageenan gels used for immobilization of Bacillus firmus

In this study, aimed at a biochemical and physical characterization of kappa-carrageenan gels used for entrapment of Bacillus firmus NRS 783 (a superior producer of an alkaline protease), effects of carrageenan concentration, gelation temperature, initial cell loading, and strength of the curing agent (KCl) on the properties of cell-free and cell-laden gels were examined. The physical properties of the differently prepared gels that were examined included density, free volume fraction, mechanical strength, and change in gel volume during gel curing. The biochemical characteristics studied included viability of gel-entrapped cells, cell leakage from cell-laden gels, and cell penetration into cell-free gels. For the range of carrageenan contents investigated [between 2% and 5% (w/v)], the mechanical strength of the gels with/without KCl curing was observed to increase with an increase in carrageenan content of gels. The mechanical strength of each gel increased substantially upon extensive curing. Free volume fractions in excess of 0.8 were observed for all gels. Of cells that were viable prior to immobilization, 90-92% remained viable after formation and extensive curing of gels for cell-gel mixtures prepared at 45 degrees C. Attempts at prolonged storage of cell-laden gel beads at 0 degrees C as stock cultures of immobilized B. firmus were unsuccessful due to a significant decline in cell viability during such storage. On the basis of the cell leakage studies, the average pore sizes of 2%, 3%, 4%, and 5% gels were deduced to increase in the following order of carrageenan content (w/v): 4%, 3%, 2%, and 5%. Commensurate with the decrease in the average pore size (or the increased tightness of the gels) with increasing carrageenan content, both the extent of cell leakage and the extent of net cell penetration decreased with increasing carrageenan content for the first three gels. Owing to non-uniform distribution of free space and much larger pores, the extent of net cell penetration in 5% carrageenan gels was considerably low, while the extent of cell leakage in 5% carrageenan gels was an order of magnitude greater than the extents of cell leakage in the other three gels.

[The flotation characteristics of Bacillus cells and spores]

Variations in hydrophobicity of the surface of bacillary cells and their capacity to flotation in the process of batch cultivation have been studied. It is shown that hydrophobicity of the cell surface increases in the course of batch cultivation of Bacillus thuringiensis, B. licheniformis and B. megaterium. Hydrophobicity of spores of the mentioned cultures is considerably higher than that of the vegetative cells. The increase of hydrophobicity of bacillary cells positively correlated with their capacity to flotation. That is why the use of flotation for the age fractionation of bacillary cells is possible: spores are concentrated in the foam while vegetative cells remain in the culture liquid.

Cibacron blue 3G-A inhibits cell separation of gram-positive bacteria

A triazine dye, Cibacron blue 3G-A (CB), is an inhibitor of cell separation of staphylococcal spp. therefore, we examined the effect of CB on growth of gram-positive bacteria other than Staphylococcus. CB added to the medium of growing cultures of strains of genus Micrococcus, Streptococcus, Lactobacillus and Bacillus caused inhibition of cell separation. Moreover, in case of Bacillus and Lactobacillus, individual cells were elongated as filament. Strains of the genus Micrococcus were as sensitive to CB as genus Staphylococcus in which the minimum concentrations of CB needed for inhibition of cell separation ranged from 15 to 100 microM. Other strains belong to genus Streptococcus, Bacillus and Lactobacillus were less sensitive; the minimum concentrations were 100 microM--25 mM.

[Bacteriologic basis for the treatment of tuberculosis]

To be fully effective, short-course chemotherapy for tuberculosis should take into account the slow growth rate, high oxygen requirement and high drug-resistant mutant emergence rate of Mycobacterium tuberculosis, as well as the type of the lesions observed and the specific activity of each antituberculous drug. Due to their unique sterilizing activities against bacilli that are not actively metabolizing, rifampicin and pyrazinamide are the key drugs for short-course chemotherapy. To prevent the selection of drug-resistant mutants and the occurrence of therapeutic failures, a combination of isoniazid, rifampicin, pyrazinamide and ethambutol should be given during the first two months of treatment. To kill persisting M. tuberculosis, and thus avoid posttreatment relapses, the isoniazid-rifampicin combination should be prescribed for à further four months.

[Hydrolase biosynthesis by morphological variants of Bacillus mesentericus as dependent on the storage conditions]

A method used to prepare the inoculum (a strain of Bacillus mesentericus, a producer of a complex of hydrolytic enzymes) has been studied for its effect on the activity of proteinases and amylases under submerged cultivation in fermenters. Optimal conditions for the culture storage and inoculum cultivation are developed to obtain standard enzymic preparations.

Permeability studies of lipid vesicles from alkalophilic Bacillus firmus showing opposing effects of membrane isoprenoid and diacylglycerol fractions and suggesting a possible basis for obligate alkalophily

Previous studies of the membrane lipids of extremely alkalophilic bacilli had indicated that both facultative and obligate alkalophiles contained a substantial fraction of isoprenoid lipid as well as high concentrations of cardiolipin. Facultative alkalophiles differed from obligate strains in having a phospholipid fatty acid composition that would be expected to result in a more ordered membrane structure. Current studies of ion permeability in vesicles prepared from lipids from obligately alkalophilic Bacillus firmus RAB and its facultatively alkalophilic strain, OF4, support the suggestion that membranes of the latter strain form a tighter barrier structure, with the difference especially pronounced at near neutral pH values. The water permeability of whole cells and the reflection coefficients for acetamide in vesicles were also consistent with a tighter membrane in the facultatively alkalophilic strain than in the obligately alkalophilic strain. The permeability properties of vesicles prepared from phospholipids from these organisms were studied as a function of the addition of either homologous membrane isoprenoid or diacylglycerol. For each permeability parameter that was assayed, in lipids from both strains, the isoprenoid fraction decreased the permeability, whereas the diacylglycerol fraction increased the permeability of the vesicles to solute.

16S ribosomal RNA analysis of Filibacter limicola indicates a close relationship to the genus Bacillus

The phylogenetic relationship of the Gram-negative, filamentous gliding bacterium Filibacter limicola was analysed by 16S rRNA oligonucleotide cataloguing. In contrast to the proposed membership of this asporogenous species in the Flexibacteriaceae, Filibacter limicola clusters phylogenetically with the Gram-positive eubacteria Bacillus pasteurii, Sporosarcina ureae and the asporogenous species Planococcus citreus. The genetic relationship is supported by several common phenotypic properties.

[Fusion of Bacillus subtilis and Bacillus licheniformis protoplasts. Interspecies recombination resulting from protoplast fusion]

Recombinants between B. subtilis and B. licheniformis were prepared by fusion of the bacterial protoplasts. Genetically marked strains SB25 trp C hisH and 168 ade-met-leu- of B. subtilis and 1001 ura-thr- and 1001 met- of B. licheniformis were used as the parent strains. The recombinants were selected with the indirect method followed by analysis of their nutrient requirements and cultural and morphological features. All the hybrids acquired the specific properties of B. subtilis. Apparently, their formation was based on the whole chromosome of B. subtilis and recombination of separate fragments of B. licheniformis with it. Hybrids with prototrophic properties with respect to one, two or three markers of the initial strains were detected independent of the genotype of the B. subtilis parent strains. Moreover, the protoplast fusion resulted in formation of hybrids which were prototrophic with respect to the amino acid markers of B. subtilis and deficient with respect to homoserine and thiamine or only thiamine, whereas the initial strains were not auxotrophic with respect to homoserine and thiamine. Thi-Hom- and a number of the prototrophic recombinants were characterized by the capacity for increased synthesis of riboflavin lacking in the initial cultures. Homologous and heterologous transformation appeared to be possible in the recombinants of the Thi-Hom- phenotype, while transformation of the initial strain SB25 by the intergenocytic markers was possible in reciprocal crossings. It is concluded that contrary to transformation of isolated DNA, protoplast fusion may result in formation of interspecies recombinants of B. subtilis and B. licheniformis with respect to different operones of amino acid synthesis.

[Morphology and cytology of Bacillus benzoevorans, a new filamentous, sheathed mesophilic species, degrading various aromatic acids and phenols]

When cultivated on solid medium or in stationary liquid medium, most of the 11 studied strains of Bacillus benzoevorans grew as unbranched, flexible, immotile filaments (or trichomes) of undefined length and 1.8 micrometer diameter. They were enclosed in a sheath giving an overall diameter of 3.6 micrometer. When cultivated in vigorously shaken liquid medium, several strains grew as separate rods (1.8 X 2.2 micrometer), did not deform the filament and contained dipicolinic acid. The cytoplasm had a granular aspect due to the presence of poly-beta-hydroxybutyric acid. The Gram reaction was variable but the Gram type was positive. Isolated and purified sheath contained 73% proteins, 12.9% reducing sugars and 8% lipids. In stationary liquid medium, the culture had a mycelial aspect and a thick pellicle formed at the surface. Colonies were circular, flat, opaque, whitish, mat and compact; they had irregular edges, spread out on the surface and did not adhere to the agar.

Bacterial cells as anti-tumour agents in man

Since conventional cancer treatments cannot guarantee the destruction of all the tumour cells present within the patient, a relatively new form of therapy has been introduced whereby bacteria are used to stimulate immune responses, which if properly generated have the potential to eliminate the few remaining tumour cells that escaped the conventional treatments. This review deals with the results of clinical trials of immunotherapy and demonstrates that although it could form the basis of an effective therapy, it still requires more experiments to increase its efficiency and to decrease its side effects, the most serious of which is to accelerate tumour growth in some instances. The review concentrates on the two main agents currently in use, Bacillus Calmette-Guérin and Corynebacterium parvum.

Induction of reversion from the L-form to the sporogenous phase of Bacillus licheniformis var. endoparasiticus (Benedek)

The rate of reversion from the L-form to the complete bacillus phase of Bacillus licheniformis var. endoparasiticus (BLE)was increased by a factor of c. x20, by growth in the presence of 1% diaminopimelic acid in a well plate, and c. x25 with a 1% hog gastric mucin spread on the plate surface. Saturated riboflavin solution and growth products of staphylococci in wells had a lesser effect. The revertants were subsequently stable when isolated in the absence of additive. The rate of reversion from a spheroplast to a diphtheroid phase was not significantly altered by these additives. These findings are of practical value in studies to distinguish between the BLE sporing bacillus and postulated phases of the organism that include diphtheroid and spheroplast L-forms and debated mycoplasma-like forms.

[Acidophilic obligate thermophilic bacteria, Bacillus acidocal-darius, isolated from the hot springs and soil of Kunashir Island]

Obligate thermophilic acidophilic cultures of Bacillus acidocaldarius were isolated from hot springs and soil of the Kunashir Island (the Kuril Islands) and Southern Sakhalin; their optimum temperature of growth is 65 degrees C and pH is 3.3--4.0. It has been shown for the first time that these organisms can be isolated from springs with either acidic or neutral and weakly alkaline pH values.

The isolation and characters of L-forms and reversions of Bacillus licheniformis var. Endoparasiticus (Benedek) associated with the erythrocytes of clinically normal persons

Thirty-eight strains of the Gram-positive bacterium identified as Bacillus licheniformis var. endoparasiticus (Benedek), referred to as BLE, were isolated in various stages of reversion form the L-forms, from 28 out of 100 samples of whole blood or erythrocytes from normal healthy subjects, after prolonged incubation. Similar results were obtained from 100 samples from hospital patients with conditions not usually associated with blood infection. BLE was isolated from only one of 125 samples of plasma, including those separated from infected erythrocytes. Isolates from cultures incubated for up to 4 months were usually in the form of spheroplasts or diphtheroid bacilli; the fully reverted phase, resembling B. licheniformis, with the capacity to form endospores, was isolated occasionally from cultures aged 1--6 months, and it constituted about half the isolates recovered from cultures aged 6--25 months. BLE was isolated in subculture, and with the usual frequency, in previously unopened, primary cultures. It did not occur in 1200 subcultures of 150 control cultures made with autoclaved or irradiated blood cells; it was not detected in the environment of the laboratory or blood-sampling areas, or on the skin or in the respiratory passages of the operators and other persons associated with the laboratory, where typical, saprophytic B. licheniformis was very rare. It is concluded that this Bacillus species exists as an L-form, associated with the erythrocytes of a large proportion of normal persons, as previously recorded by several observers. Some of the morphological variants associated with the L-cycles have in the past been described as different organisms, for example L-forms of various bacteria or mycoplasmas, and the diphtheroid stage has been thought to belong to the genera Corynebacterium and Listeria. The sporogenous stage, although frequently described, has normally been discounted as a contaminant. These observations do not admit of any conclusion in respect of the claims that such bacteria may have a role in arthritis, cancer or other diseases.

[Study of the spiral and spindle-shaped formations in cultures of Bacillus larvae (White 1906) causing foulbrood in bees]

The authors have been studying the bacterial diseases of the brood for a fairly long time. American and European foul brood has been studied with the highest attention. Cultures of Bacillus larvae (White, 1906) were examined both in freshly isolated strains and in collection strains of this micro-organism. In cases of foul brood, the pathological material was found to contain not only the typical rods of B. larvae but also immobile spiral forms which are usually referred to in literature as fragments or developmental forms of B. larvae. These spiral forms were found to constitute spindle-shaped formations in the culture of B. larvae; the multiplication of these spindles depends on the presence of the rods of B. larvae and their development and reproduction can be observed on wet gelatine agar in a Petri dish turned upside down under a normal microscope (10 X 10 magnification). In the combined liquid medium, used in the experiments, these formations disintegrate into immobile spirals; if re-cultivated on a solid medium they re-assume their spindle shape with transverse meridian arrangement (in different amounts). Staining for proving the presence of nucleic acids does not eliminate the possibility of these formations being separate micro-organisms which cannot be stained by current staining methods but can be represented by the contrast method according to Burri, or by silvering according to Klein. The authors succeeded to separate these micro-organisms, but without the rods of B. larvae the colonies of these formations are feeble.

[Conditions for formation of heteromorphic forms of Bacillus brevis and their cytology]

The conditions of formation of Bacillus brevis var. GB heteromorphous forms were studied both under natural conditions and in the course of action of various factors. Natural polymorphism of the culture is low. It increases as the temperature of cultivation is lowered down to 28 degrees C or when the culture is kept at 5--6 degrees C in a refigerator. The P- and S forms of dissociation display higher polymorphism than than P+ and R variants. Cytological investigation has shown that heteromorphous forms are very large and contain gigantic nuclear formations in the form of solid bodies or bands. The sharp increase in the size of the nucleoids, their aggregation and splitting (breaking down of a band into sepraate units, transverse division of large nucleoids), as well as the data of biochemical analysis suggest the polygenomic or polyenergid nature of the giant heteromorphous forms of Bacillus brevis var. GB.

[Viability of a Bac. licheniformis 749/c culture and its formation of penicillinase during storage in the lyophilized state]

The amount of the enzyme produced and the colony morphology of Bac. licheniformis 749/C, the penicillinase-producing organism were studied after storage for 3 years in ampoules at a temperature of 4--10 degrees C, in lyophilized form in sodium glutamate, polyvinylpirrolidone, their mixture and horse serum. The highest rate of the culture growth was observed after storage in lyophlized form in sodium glutamate, though the culture was vialable in all other protective media. Two culture types approximately in an equal ratio were observed in the population platings of the culture lyophilized in various protective media.

Biochemical studies on an acidophilic, thermophilic bacterium, Bacillus acidocaldarius: isolation of bacteria, intracellular pH, and stabilities of biopolymers

Acidophilic, thermophilic bacteria were isolated from Japanese acidic hot springs. They were spore-forming rods, identified as Bacillus acidocaldarius. DNA extracted from these acido-thermophiles showed no abnormality in chemical structure; it was instantly denatured and gradually decomposed giving rise to apurinic acid in a hot acid environment milder than the optimal conditions for the growth of the acido-thermophiles. Glyceraldehyde-3-phosphate dehydrogenase extracted from B. acidocaldarius was not active at pH 5 or less, and was resistant to heat at neutral but not acid pH. The intracellular pH was computed to be neutral by using dimethyl-2,4-oxazolidinedione. When uncouplers or inhibitors of respiration were added to the cells suspended in hot acid solution, the estimated pH was not changed and glyceraldehyde-3-phosphate dehydrogenase in the cells was not denatured. These results suggest that the cytoplasm of B. acidocaldarius is a hot neutral environment, and that a pH gradient across the cell envelope can be maintained even when oxidative phosphorylation or respiration is inhibited.