[The composition of a population of cloned cultures of revertant Vibrio cholerae L forms]. / Izuchenie sostava populiatsii klonovykh kul'tur revertantov L-form kholernykh vibrionov.

The process of L-transformation and L-transformed state duration have been studied for their effect on variability of main characters of revertant cultures of choleric vibrions L-forms at the population level with the use of cloned cultures of the choleric vibrions. The study was conducted on two strains of the choleric vibrion of the eltor biovar in different periods of storage in the L-transformed state (1, 3, 6 months). It has been revealed that characters of the species and biovar remained stable despite the influence of L-transforming agents. The characters of clone cultures characterizing virulence (sensitivity to KhDF phages, hemolytic activity, toxin production and virulence for sucking rabbits proved to be subjected to variability to the greatest extent with simultaneous preservation of the toxin-production gene. A resistant change of the serovar (from Inaba to Ogava) is observed only in one revertant-subculture of the virulent strain.

[Genetic determination of the vibriocinogenicity trait in Vibrio cholerae of the El Tor biotype]. / Issledovanie geneticheskoi determinirovannosti priznaka vibriotsinogennosti u kholernykh vibrionov biotipa El-Tor.

In two different strains of cholera vibrios two recA-dependent plasmids, pVib I (1.9-2.2 Md) and pVib II (5.2-5.8 Md), have been detected. These plasmids determine the synthesis of vibriocin, coagulase and fibrinolysin, which has been established by the cotransformation of the DNA of plasmids pVib I and pBR322 and by the transfer mobilization with the use of plasmid RP4.

[Allomonads--a new group of microorganisms of the family Vibrionaceae. V. Taxonomic position of the allomonads based on a study of their DNA]. / Allomonady--novaia gruppa mikroorganizmov semeistva Vibrionaceae. Soobshchenie V. Taksonomicheskoe polozhenie allomonad na osnove izucheniia ikh DNK.

The DNA of Allomonas, a new group of microorganisms, has been studied to determine the taxonomic status of this group. In the nucleotide composition of the DNA of a typical representative of this group 57.4 mol % G + C have been revealed, which permits to sharply differentiate Allomonas from vibrios and Plesiomonas. A relatively low level of similarity between the DNA of Allomonas and that of other representatives of the family Vibrionaceae has been determined by the method of molecular DNA hybridization (6-18% of homologies), this level being approximately the same in vibrios, Plesiomonas and Aeromonas. These data indicate the necessity of regarding Allomonas as a separate genus of the family Vibrionaceae.

Allomonads - a new group of microorganisms of the Vibrionaceae family.

A total of 24 strains of microorganisms with basic marks relating them to the family of Vibrionaceae were isolated from human faeces, liquid sewage and waters of surface reservoirs contaminated with sewage. The study of biological, cultural and biochemical characteristics, determination of phenotypic similarity according to Adanson-Sneath, investigation of DNA composition and extent of DNA hybridization by the methods of gene taxonomy induced us to establish taxonomic independence of the discovered strains at the level of the genus Allomonas gen. nov. with so far the only species A. enterica sp. nov.

[Makeup of a population El Tor vibrios according to their agglutinability by type-specific sera]. / Izuchenie sostava populiatsii vibrionov El' Tor po aggliutinbel'nosti tipospetsificheskimi syvorotkami.

The authors studied population composition of 14 strains of EL Tor vibrios. Of 7 strains of Ogava serological type the population composition was homogeneous in 2, and heterogeneous in 5. All the 7 strains of EL Tor vibrios of Inaba serological type had homogeneous population composition. Changes of the existence conditions of EL Tor vibrios of Ogava serological type, containing in their population 5% cells of Hikoshima serological tupe, led to separation of the cells of Inaba serological type; under the same conditions, in El Tor vibrios of Ogava and Inaba serological type with homogeneous population the latter was stable.