[Lipids of initial and mutant cultures of Penicillium chrysogenum, producers of penicillin]. / O lipidakh iskhodnykh i mutantnykh kul'tur Penicillium chrysogenum-produtsentov penitsillina.

Comparative investigation of lipogenesis in 2 initial and 4 mutant strains of Penicillium chrysogenum showed that there were no noticeable differences in the composition of the lipid fatty acids in these strains. Certain shifts in the ratio of definite lipid fatty acids in the mutant strain deficient by synthesis of lysine and isoleucine (increased contents of oleic acid) were revealed. A marked influence of the physiological conditions on lipogenesis in the mutant with multiple deficiency by amino acids, vitamins and nucleotides was observed.

[Cytological study of early stages of regeneration of protoplasts of fungi and Streptomyces]. / Tsitologicheskoe izuchenie rannikh étapov regeneratsii protoplastov gribov i streptomitsetov.

Early stages of Penicillium chrysogenum 51 and Streptomyces lividans 66 protoplast regeneration on solid media were studied microscopically under conditions of microcompartments. It was shown that at the early regeneration stages there were both rapid reversion into the mycelial form and a retarded one. In P. chrysogenum retarded regeneration resulted in formation of hypha-like structures or protoplast breaking into fragments of various sizes. Some of the fragments restored the cell walls and mycelial organization whereas the others lysed. As a result of the breaking and compartmentalization of the viable areas one protoplasts formed several centers of P. chrysogenum colony reversion. Retarded regeneration of protoplasts in S. lividans 66 resulted in their growth and multiplication in the protoplast-like L-form. On media with penicillin, glycine and horse serum there were isolated colonies of S. lividans L-forms subject to passages or reversion depending on the medium composition.

[Antibiotic production by variants of Penicillium chrysogenum isolated after protoplast formation and exposure to mutagens at the protoplast stage]. / Antibiotikoobrazovanie u variantov Penicillium chrysogenum, poluchennykh posle protoplastirovaniia i obrabotki mutagenami na stadii protoplastov.

A procedure for protoplast formation in the penicillin-producing organism Penicillium chrysogenum was developed. The yield of the protoplasts was high, the protoplasts were stable and capable of regeneration. Two types of the protoplast regeneration were revealed. The spores and protoplasts were treated with UV light and N-nitroso-N'-methyl biuret and their effect on production of the antibiotic by the isolated variants was studied. It was shown that the protoplasts of P. chrysogenum were more liable to the mutagenic effect of UV light and nitroso methyl biuret than the fungus conidia. It is possible to use this specific feature in intensification of selection aimed at isolation of highly productive strains of P. chrysogenum.

[Ratio of the mutation spectrum to the physiological state of the Penicillium chrysogenum cell. Auxotrophic mutations induced by UV rays at different stages of DNA replication]. / Zavisimost' spektra mutatsii of fiziologicheskogo sostoianiia kletki Penicillium chrysogenum. Auksotrofnye mutatsii, indutsirovannye UF-luchami v ravlichnye stadii replikatsii DNK.

The spectrum of the mutations obtained with exposure of nonactivated spores of Pen. chrysogenum to N-nitrozo-N-methylbiuret (NMB) was studied and it was shown that the mutations associated with blocking of amino acid synthesis predominated. When activated spores of Pen. chrysogenum were treated with the mutagen, correlation was observed between the spectrum of the induced mutations, the physiological state of the cells and the exposure time. It is supposed that the mutagen molecule affects the replicating part of the DNA molecule. Schemes for predominating liberation of the mutations according to the markers in time were developed. This may give an idea of the order of the markers in genome.

[Penicillin formation by biochemical mutants of Penicillium chrysogenum and their spontaneous revertants]. / Obazovanie penitsillina biokhimicheskimi mutantami Penicillium chrysogenum i ikh spontannymi revertantami.

The capacity for the antibiotic production in the auxotrophs of Penicillium chrysogenum with various deficiency and their revertants was studied. It was found that the capacity for penicillin synthesis was impaired to various degrees in the majority of the auxotrophs. Variants with the penicillin production levels by 13--20 per cent higher than those in the initial prototrophic strain were isolated for the first time in selection of the eukaryotes with the method of obtaining highly active revertants from auxotrophs according to the scheme "prototroph-auxotroph-prototroph".

[Ratio of the mutation spectrum to the physiological state of the Penicillium chrysogenum cell. Auxotrophic mutations induced by N-nitroso-N-methylbiuret in exposure at different stages of DNA replication]. / Zavisimost' spektra mutatsii ot fiziologicheskogo sostoianiia kletki Penicillium chrysogenum. Auksotrofnye mutatsii, indutsirovannye N-nitrozo-N-metilbiuretom pri vozdeistvii na raznye stadii replikatsii DNK.

The effect of UV light on activated conidia of Penicillium chrysogenum, strain 39 was studied. It was found that the spectrum of the auxotrophic mutations induced by UV light during replication of DNA changed with the dose of the mutagen and was specific to every dose. The schemes of predominating mutation induction during DNA replication under the effect of 2 doses of UV light were developed.

[Prolonged storage of fungal culture collections on agarized media]. / Dlitel'noe khranenie kollektsionnykh kul'tur gribov na agarizovannykh sredakh.

The study of the efficacy of storage of 300 fungal cultures on agarized media with repeated passages showed that the survival level of the fungi stored with this method may serve an additional biological characteristics for some species: Penicillium chrysogenum, Penicillium sclerotiorum and others. When the fungi were stored on agarized media with repeated passages for a prolonged period of time, there were observed lower levels of sporulation, sclerotia formation and pigmentation in some cultures.

[Mutagenic action of N-nitrosodimethylurea on Actinomyces rimosus and Penicillium chrysogenum]. / Mutagennoe deistvie N-nitrozodimetilmocheviny na Actinomyces rimosus i Penicillium chrysogenum

High mutagenic activity of N-nitrozodimethylurea (NDMU), an agent of the group of the nitrozo compounds not studied in detail was shown with respect to prototrophic and auxotrophic strains of Actinomyces rimosus, an organism producing oxytetracycline and Penicillium chrysogenum, an organism producing penicillin. The rate of direct and back mutations in the auxotrophic strain of Act. rimosus under the effect of NDMU was many times higher than that of spontaneous mutations. NDMU was used at one of the selection stages at which a more active variant of Act. rimosus was obtained. This is evident of a possible use of the mutagen for induction of variation with respect to the quantitative feature of oxytetracycline production. A great number of morphologically changed forms and biochemical mutants of Pen. chrysogenum formed under the effect of this substance. NDMU induced a mutant of Pen. chrysogenum capable of selective synthesis of 6-aminopenicillinic acid without addition of the precursor.

[Bacteria-infectious viruses in Penicillium chrysogenum strains with differing antibiotic activity]. / Virusy infektsionnye dlia bakterii v shtammakh Penicillium chrysogenum s razlichnoi antibioticheskoi aktivnosti

A new virus capable of replication on E. coli C was isolated from Penicillium chrysogenum. Six strains of P. chrysogenum differing in the cultural-morphological and biochemical properties and the titer of virus PBV5 were studied. The data provided a supposition that there were definite connections between the titer of virus PBV5 in the mycelium and the fungus ability for the antibiotic production.

[PBV5 virus induction in Penicillium chrysogenum mycelium]. / Induktsiia virusa PBV5 v mitselii Penicillium chrysogenum

The effect of some physical (increased temperature, UV light) and chemical (N-nitrosomethylbiuret, proflavin, acridine orange) factors on the virus titer in 2 strains of Penicillium chrysogenum was studied. Thermoinactivation of the virus and its induction under the effect of UV light and proflavin were shown. Slight induction was observed with N-nitrosomethylbiuret and acridin orange. It was supposed that induction of the virus in the mycelium of Penicillium chrysogenum was spontaneous.