Folia Microbiologica

Levi, M.; Sakayan, N.; Livshits, M.; Meschcheryakova, I.

doi: 10.1007/BF02878119pmid: 1176044

A mathematical expression of the accumulation of the plasma cells in the spleen of CBA mice immunized intraperitoneally is presented. The dependence of the plasma cell reaction in the spleen on the kinetics of antigen concentration in the blood was confirmed. For the transition from antigen to plasma cells, index A was proposed. The mean values of index A were used for comparison of the calculated and experimental values of the plasma cell reaction and the recorded differences were not great. In a similar way, index A was used for prediction of plasma cell accumulation in the spleen of animals, immunized with a mixture of two soluble antigens — capsular antigen ofPasteurella pestis and complete antigen ofFrancisella tularensis. The calculated values of plasma cell reaction corresponded to experimental values.

Smigán, P.; Gbelská, Y.

doi: 10.1007/BF02878114pmid: 1176043

A yeast mutant with an impaired system of translocation of adenine nucleotides across the mitochondrial membrane, which stops dividing after superposition of the λ - mutation, was investigated. The results of this work indicate that combination of the op1 mutation with the λ- mutation in a single cell results in interruption of synthesis of polysaccharides and DNA leading to cessation of division of theop 1λ mutant. The mechanism of this effect remains unclear.

Vojtísek, V.; Slezák, J.

doi: 10.1007/BF02878110pmid: 1100492

The differential rate of synthesis of penicillinamidohydrolase (penicillin acylase — EC 3.5.1.11) was studied inEscherichia coli growing in some chemically defined media and in a complex medium. The enzyme is synthesized at a constant rate only during the exponential phase of growth of cells. Its synthesis is induced most effectively (with respect to quantity) by phenylacetic acid. The induction lag of the enzyme synthesis in a medium with acetate corresponds to two generation times. The highest rate of the enzyme synthesis is reached in a medium containing phenylacetic acid as the only source of carbon and energy. The enzyme synthesis is fully repressed by an increased concentration of dissolved oxygen in the medium, even whenEscherichia coli is cultivated in the medium with phenylacetic acid as the only carbon and energy source.

Krizková, L.; Balan, J.

doi: 10.1007/BF02878118pmid: 1236823

Oomycetes and predaciousFungi imperfecti were preserved viable for four years by storage at 22°C under paraffin oil. This method of culture preservation was checked on 52 species belonging to 4 orders and 13 genera.

Volfoá, O.

doi: 10.1007/BF02878112pmid: 240764

Oxidation of methanol, formaldehyde and formic acid was studied in cells and cell-free extract of the yeastCandida boidinii No. 11Bh. Methanol oxidase, an enzyme oxidizing methanol to formaldehyde, was formed inducibly after the addition of methanol to yeast cells. The oxidation of methanol by cell-free extract was dependent on the presence of oxygen and independent of any addition of nicotineamide nucleotides. Temperature optimum for the oxidation of methanol to formaldehyde was 35°C, pH optimum was 8.5. The Km for methanol was 0.8mM. The cell-free extract exhibited a broad substrate specificity towards primary alcohols (C1-C6). The activity of methanol oxidase was not inhibited by lnni KCN, EDTA or monoiodoacetic acid. The strongest inhibitory action was exerted byp-chloromercuribenzoate. Both the cells and the cell-free extract contained catalase which participated in the oxidation of m||ethanol to formaldehyde; the enzyme was constitutively formed by the yeast. The pH optimum for the degradation of H2O2 was in the same range as the optimum fop methanol oxidation,viz. at 8.5. Catalase was more resistant to high pH than methanol oxidase. The cell-free extract contained also GSH-dependent NAD-formaldehyde dehydrogenase with Km= 0.29mM and NAD-formate dehydrogenoae withK m = 55mM.

Plachý, J.

doi: 10.1007/BF02878117pmid: 1100493

The auxotrophic mutantCorynebacterium 9366-EMS/184, requiring isoleuoine accumulates about 22 g of L-valine per litre after a 96 h cultivation in a medium containing 15% sucrose and 1% ammonium acetate.

Mátlová, S.

doi: 10.1007/BF02878115pmid: 170174

Gradual transfers of the strainEscherichia coli B/r on M9 agar with increasing concentrations ofcis-platinum (II) diamminochloride (cis-Pt(II)) yielded a resistant strain SM 405 capable of growing on liquid M9 medium containing 250 μmcis-Pt(II). The parent strainEscherichia coli B/r is completely inhibited in both division and growth atcis-Pt(II) concentrations as low as 30 μM. The resistant mutant has a longer doubling time than the parent strain. No other differences were found between the two strains. To elucidate the nature of the resistance, the effect ofcis-Pt(II) on the survival of the two strains was compared with that of nitrogen mustard, UV light and ethyl methanesulphonate (EMS). The resistant strain SM 405 was found to be more hardened against the lethal action of UV light and nitrogen mustard but less so against EMS. It had also a higher ability of a host-cell reactivation of UV-irradiated phage T3. The different resistance of the B/r and SM 405 strains is probably due to a mutation increasing the effectiveness of the excision repair in the latter.

Betina, V.; Janstová, D.; Spisiaková, J.

doi: 10.1007/BF02878116pmid: 51812

Some antibiotics and synthetic inhibitors affect, in several ways, the life cycle ofNeurospora crassa (germination of conidia → myceliar growth → formation of conidia). Bikaverin, cyanein, scopathrioin and phenethyl alcohol retard the germination of conidia, without inhibiting it completely. 5-Fluorouracil, ramihyphin A and zygosporin A (cytoohalasin D) do not inhibit the germination. Bikaverin brings about a thickening of the hyphae of growing mycelium. Ramihyphin A, cyanein, scopathricin and zygosporin A stimulate the ramification of hyphae while 5-fluorouracil and phenethyl alcohol do not affect the myceliar morphology apart from their inhibitory effect on growth. Actinomycin D, 5-fluorouracil, cycloheximide, ramihyphin A and partially also sodium iodoacetate inhibit to a different degree the photoinduced formation of conidia. The inhibition by 5-fluorouracil is very conspicuous when the agent is present during the photoinduction but considerably weaker when it is applied 2 h after the photoinduction.

Sajdl, P.; Rehácek, Z.

doi: 10.1007/BF02878120pmid: 1176045

Kopecká, M.

doi: 10.1007/BF02878108pmid: 1100491

The formation of protoplasts of the fission yeastsSchizosaccharomyces pombe andSchizosaccharomyces versatilis after the combined application of snail enzymes andTrichoderma viride enzymes in an osmotic stabilizer (0.4m KC1, pH 5.5) was studied by light and electron microscopy. The effect of the enzymes used leads during 30 min to the formation of 100% protoplast population. Using electron microscopy no original walls or wall remnants were detected in the suspension of protoplasts. Protoplasts are viable and in liquid nutrient medium they regenerate cell walls and revert into normal cells. Such a protoplast population may be useful for biochemical study of protoplast metabolism by quantitative methods as well as for the chemical study of regenerating cell walls.