[Variability of Vibrio cholerae as affected by subbacteriostatic concentrations of antibiotics]. / Izuchenie izmenchivosti kholernykh vibrionov pod vliianiem subbakteristaticheskikh kontsentratsii antibiotikov.

The effect of subbacteriostatic concentrations of some antibiotics on variation of the features characterizing the serovar and biovar of the cholera germ was studied on 10 strains of V. cholerae E1 Tor of the Inaba serovar having the typical properties. It was shown that even a single exposure to the subbacteriostatic concentrations of some antibiotics resulted in formations of clones differing from the parental strains by a number of significant features, such as the antigenic structure, phage lysability and enterotoxicity. The new features were inherited in a number of generations on multiplication in culture media and in sensitive animal hosts.

[Action of Vibrio cholerae enterotoxin on microorganisms]. / Deistvie énterotoksina Vibrio cholerae na mikroorganizmy.

The damaging of V. cholerae enterotoxin on anaerobic dehydrogenases of different species of opportunistic microorganisms has been revealed. Experiments, carried out both in vivo and in vitro, have shown that under certain conditions this enterotoxin may act as one of the factors of the intra- and interspecific antagonism of bacteria.

Investigation of populations heterogeneous according to O-antigen in Vibrio cholerae cultures.

The O-antigenic composition of 36 cultures of Vibrio cholerae agglutinating simultaneously with 01 cholera sera and 0 sera to NAG vibrios of the Sakazaki collection was investigated. It has been established experimentally that under the effect of medium and environmental conditions such cultures dissociate to subcultures differing in their affiliation to different serological groups according to 0 antigen. The passage of these cultures in the organism of susceptible animals promotes preservation of 01-group clones whereas the passage in peptone water or prolonged storage under unfavourable conditions result in the predominance of clones of different serological affiliation. The proposition has been put forward that the observed vibrio cultures are genotypically capable of producing, besides the 01 group, a number of 0 antigens. Phenotypical manifestation of the antigenic structure in the respective individuals of the population depends on the conditions of the environment.

[Antibiotic sensitivity of bacteria of the family Vibrionaceae isolated from the intestines of swine]. / Chuvstvitel'nost' k antibiotikam bakterii semeistva Vibrionaceae, vydelennykh iz kishechnika svinei.

Bacteria of Aeromonas hydrophila subsp., biotype 1 and Aeromonas anaerogenes, biotype 2, as well as Proteolitica of the vibrio pasahumoliticus biotype were isolated from the intestine of pigs with diarrhea. Close antibiotic sensitivity of the isolates was shown. The differences in their sensitivity were not sufficient for defining the taxonomic features.

[NAG vibrio sensitivity to antibiotics]. / Izuchenie chuvstvitel'nosti NAG-vibrionov k antibiotikam.

Sensitivity of 575 NAG-vibrio strains isolated from various substrates in 1978-1980 to 14 antibiotics was studied and compared with the results of an analogous study performed in 1968 by Z. V. Ermolyeva et al. It was shown that sensitivity of NAG-vibrio to chloramphenicol, ampicillin, cephaloridine and streptomycin decreased. However, NAG-vibrio remain to be sensitive to tetracycline, chloramphenicol and gentamicin. Resistance of the majority of the strains to ampicillin, carbenicillin, cephaloridine and polymyxin M was noted.

[Antibiotic sensitivity and other properties of bacteria of the genus Aeromonas]. / Chuvstvitel'nost' k antibiotikam i drugie svoistva bakterii roda Aeromonas.

Antibiotic sensitivity and other biological properties of Aeromonas and NAD-vibrios isolated from water of open waterbodies were studied comparatively. It was found that the organisms of these genera had a definite similarity with respect to antibiotic sensitivity, morphological, cultural and some antigenic properties. The differences in the antibiotic sensitivity of these organisms were not sufficient for definition of the taxonomic features.

[Polyvalent diagnostic cholera phage]. / Polivalentnyi diagnosticheskii kholernyi fag

A polyvalent diagnostic bacteriophage for rapid identification (in 6-10 hours) of cholera vibrio of both biotypes has been constructed of virulent E1 Tor phages and recommended for laboratory practice. Polyvalent diagnostic bacteriophage is strictly specific, inactive against the nonagglutinating vibrios, microbes of enteric group and those closely affiliated.