[Accumulation of the infectious virus and the viral antigen during the multiplication of the hepatitis A virus in an embryonic kidney cell culture of the rhesus macaque (FRhK-4)]. / Nakoplenie infektsionnogo virusa i virusnogo antigena pri razmnozhenii virusa gepatita A v kul'ture kletok pochki émbriona makaki rezusa (FRhK-4).

Growth characteristics of the HAS-15 strain of human hepatitis A virus (HAV) in rhesus monkey foetal kidney cell line (FRhK-4) are described. The conditions optimal for the accumulation of infectious HAV and viral antigen (HAAg) in the infected cells and tissue culture fluids were studied. The production of infectious HAV occurred in the first stage while in the second stage predominantly HAAg was accumulating intracellularly. Serological properties of the cultivated HAV proved to be very similar to those of the HAV occurring in hepatitis A patients.

[Dynamics of the accumulation of virus particles with different physico-chemical properties in FRhK-4 cells infected with hepatitis A virus]. / Dinamika nakopleniia virusnykh chastits s razlichnymi fiziko-khimicheskimi svoistvami v infitsirovannykh virusom gepatita A v kletkakh FRhK-4.

The propagation time-course of hepatitis A virus (HAV, strain HAS-15) in continuous culture of the foetal rhesus monkey kidney cells (FRhK-4) was investigated. The HAV infectivity and viral RNA content in the infected cells reached the maximal level 5-8 days after infection, while accumulation of hepatitis A antigen (HAAg) continued for 2-3 weeks more. Viral particles with the densities 1.27-1.28 g/cm3 and 1.18-1.22 g/cm3 were isolated from the infected cells as well as the mature virions with the buoyant density 1.33-1.34 g/cm3 in CsCl. The concurrent accumulation of mature virus and "light" particles (1.18-1.22 g/cm3) was registered during infection. Viral particles with the density 1.27-1.28 g/cm3 accumulated predominantly from the 14th to the 21st-24th days after infection. The mature virions (1.34 g/cm3) as well as the particles with the density 1.24-1.25 g/cm3 were isolated from supernatant precipitated by ammonium sulphate. The HAAg activity of both fractions increased progressively in equal proportion in course of infection.

[Association of the hepatitis A virus with the membranes of infected cells]. / Assotsiatsiia virusa gepatita A s membranami infitsirovannykh kletok.

"Light" viral antigen (HAAg) with buoyant density 1.20 g/cm2 and sedimentation coefficient 92S are accumulated together with mature viral particles in Hepatitis A virus (HAV) infected FRhK-4 cells. This HAAg is localized predominantly in endoplasmic reticulum fraction of infected cells, while nature virions are localized in cytosol. In contrast to mature virus, "light" HAAg is sensitive to trypsin digestion and is not able to hybridize with synthetic oligodeoxinucleotide which is complementary to structural part of HAV RNA. Antigenic properties of mature virus and "light" antigen are compared.

[Cloning the operon genes of riboflavin biosynthesis in Bacillus subtilis on plasmid vector pBR322 in Escherichia coli]. / Klonirovanie genov operona biosinteza riboflavina Bacillus subtilis na plazmidnyi vektore pBR322 v Escherichia coli.

The operon for riboflavine biosynthesis of Bacillus subtilis wild type and its operator-constitutive derivative have been cloned in Escherichia coli cells on the plasmid pBR322 vector. The plasmids constructed were able to transform strains of E. coli and Bac. subtilis from Rib- to Rib+ phenotype. A DNA insert into the EcoRI site of pBR322 causes a decrease in tetracycline gene expression. The operator of the riboflavine operon of Bac. subtilis does not participate in regulation of the operon expression in E. coli cells.

[Bacillus licheniformis as an object for the propagaton of heterologous genetic material from bacilli]. / Bacillus licheniformis kak ob"ekt dlia razmnozheniia geterologichnogo geneticheskogo materiala batsill.

Bacillus licheniformis was transformed with plasmids pUB110 and pJJ10 (pUB110 - pBR322) isolated from Bac. subtilis and Escherichia coli, respectively. It was revealed that the structure and genetic properties of the plasmids did not change during the transformation process. pJJ101 (pJJ10-rib) DNA isolated from E. coli and containing helper pJJ10 plasmid was used, as a recipient. It was shown that pJJ101 rib markers were "rescued" by the resident plasmid during transformation of Bac. licheniformis (pJJ10). Plasmid pLP1 containing ribB, ribD, Kmr genes and the pUB110 replicator, was isolated from the transformants. pLP1 plasmid might be considered as a detected derivative of the parental pJJ101 plasmid. The deletion is presented by 3,9 MD segment that contains the pBR322 replicator. pLP1 DNA is capable of transforming plasmidless strains of Bac. licheniformis and Bac. subtilis.

[Chemical composition of the cell wall of Streptomyces chrysomallus which produces the antibiotic aurantin]. / Khimicheskii sostav kletochnoi stenki Streptomyces chrysomallus, obrazuiushchego antibiotik aurantin.

The cell wall chemical composition of Streptomyces chrysomallus producing the antibiotic aurantin was studied. The cell wall represents 11--13% of the dry cell weight and contains three major polymers, namely, peptidoglycan, ribitol teichoic acid and a polysaccharide. Each muramic acid of peptidoglycan has a peptide subunit which consists of two alanine residues, glutamic acid and diaminopimelic acid residues. Peptide chains are connected with bridges consisting of one glycine residue. The poly(ribitol phosphate) chain contains glucosyl substituents and O-acetyl groups. The main monosaccharides of the polysaccharide are glucose and galactose; mannose, fucose and galactosamine are found in minor amounts. The composition of the cell wall changes during cell development and aging: the content of teichoic acid decreases while that of the polysaccharide increases. Possible factors causing these changes are discussed.

[UV-mutagenesis in Bacillus subtilis. VII. Induction of auxotrophic mutants]. / Izuchenie UF-mutageneza u Bacillus subtilis. Soobshchenie VII. Induktsiia auksotrofnykh mutantov.

An experimental testing of material from thin-layered, transparent in passing light, colonies which appear with some frequency after plating Bacillus subtilis cells on agar medium with limited enrichment, has shown that such colonies are formed by auxotrophic mutants. The growth requirements for many of them has been identified. The most of mutants can be reversed to original phenotype by UV-irradiation. The frequency of auxotrophs increases after UV-irradiation of suspension of original cells. The sensitivity of auxotrophic mutants to inactivating action of UV-light is near to that of original cells, hence the increase of the frequency of mutants with dose is a result of induction, but not of selection of preexisting spontaneous auxotrophic mutants. The frequency of induced auxotrophs, in contrast to that of suppressor revertants, badly give way to declining in the time of temporary inhibition of postradiation growth. In the case of Bac, subtilis, the system of induced auxotrophic mutants on the medium with limited enrichment is rather comfortable in use and can be recommended for studying UV-induced mutagenesis in structural genes as well as for testing mutagenic activities.

[Ratio of glycan to teichoic acid in Actinomyces thermovulgaris cell wall]. / O sootnoshenii glikana i teikhoevoi kisloty v kletochnoi stenke Actinomyces thermovulgaris

The molar ratio between glycan and teichoic acid was studied in the cell wall of Actinomyces thermovulgaris. A chain of teichoic acid consisting of 13 glycerophosphate units was found to correspond to 6--7 disaccharide units of glycan. The cell wall contains 31% of the glycan of the glycopeptide and 25% of teichoic acid. The content of glycan was calculated using the concentration of muramic acid in the wall. The cell wall was found to contain 1.02% of O-acetyl groups.

[Teichoic acid content in the cell wall of Actinomyces rimosus LST-118 in the process of ontogeny]. / Soderzhanie teikhoevoi kisloty v kletochnoi stenke Actinomyces rimosus LST-118 v protsesse ontogeneza

Polymeric compounds of the cell walls of Act. rimosus were studied during the actinomycete growth. It was found that the content of teichoic acid decreased 2 times by the end of development of Act. rimosus, while content of glycane polymer remained approximately at the same level. The molar ratios of teichoic acid and glycopeptide glycane were determined.