Biomedical subjects

N A Baranova

Publications and source records attributed to N A Baranova.

At least 19 recordsLinked to original sources

PubMed1995

[Action of lovastatin--an inhibitor of cholesterol biosynthesis on bacterial bioluminescence].

The action of lovastatin, a competing inhibitor of 3-hydroxy-3-methylglutaryl CoA reductase, on bacterial bioluminescence was studied. The lovastatin lactone form and sodium salt of mevinolinic acid inhibited bacterial luciferase in vitro but did not affect bioluminescence of the intact cells of the luminous bacteria. The inhibition was found to be of a competing character in regard to aliphatic aldehyde, the bacterial luciferase substrate. Conditions under which the bioluminescence inhibition was proportional to the lovastatin concentration in the incubation mixture and a bioluminescence method for quantitative determination of the inhibitor were developed.

Anticholesteremic Agents↗

PubMed1991

[Antibiotic activity of marine gram-negative bacteria].

An antimicrobial substance was isolated from the culture fluid of Vibrio fischeri belonging to ++gram-negative sea bacteria. The substance was shown to be highly active against ++gram-positive cocci and less active against some other ++gram-positive bacteria and fungi. The active substance was defined as a low molecular weight compound which appeared to be thermostable and had positive ninhydrin reaction. The antibiotic formed when the culture was grown in the media containing sea water and protein hydrolysates or yeast extract during the exponential phase. The maximum antibiotic activity was observed during the stationary phase of culture development.

Anti-Bacterial Agents↗

PubMed1989

[Production of antibiotic substances by natural variants of the marine bacterium Vibrio Fischeri].

It was shown that under definite conditions there was competition between natural variants of sea bacteria belonging to V. fischeri. Natural variants of V. fischeri, strain 6 differed in their resistance to streptomycin and had different growth rates under conditions of limited aeration. Morphologically all the variants were identical. V. fischeri P-0, V. fischeri P-1 and V. fischeri P-2 were studied. The study revealed that V. fischeri P-0 produced a non-dialysing thermostable trypsin-sensitive substance inhibiting the growth of V. fischeri P-1 and V. fischeri P-2. The maximum activity of the antibacterial substance was observed when V. fischeri P-0 was grown in a liquid medium with peptone and yeast extract without agitation at 26 degrees C. The inhibiting substance was also active against V. fischeri BKM B995 and V. fischeri P-7 isolated as a result of V. fischeri P-0 exposure to ethidium bromide. The substance had no effect on the following bacterial species: Aeromonas liquefaciens 301, Achromobacter liquefaciens, Pseudomonas putida 15, Pseudomonas fluorescence 7, Escherichia coli AH-32 and Staphylococcus aureus.

Anti-Bacterial Agents↗

PubMed1985

The inhibition of bacterial bioluminescence by xenobiotics.

The effect of various xenobiotic substrates of microsomal cytochrome P-450, including dimethylaniline, ethylmorphine, hexabarbital and aminopyrine, on the bioluminescence of the bacteria Vibrio fischeri and the bacterial luciferase mixed-function oxidase system is described. These compounds are effective inhibitors of the luminescence reaction. The inhibition provided evidence for the competitive nature of the interactions between xenobiotics and an aliphatic aldehyde, which is a substrate of bacterial luciferase, at the binding site for cytochrome P-450. The bioluminescence method is suitable for the analysis of metabolism and detoxication of various xenobiotics.

Aminopyrine↗

PubMed1983

[Preservation of lactic acid bacteria].

The lyophilized Streptococcus lactis, S. cremoris, S. diacetilactis, Lactobacillus bulgaricus, L. casei C10, L. caucasicus cultures have had a great number of viable cells after 4 years storage. L. casei and S. cremoris strains endured 3 months storage at -30 degrees C and in the sterile vaseline oil for 8 months. After storage S. cremoris strains showed the high level of the lactic acid formation and of proteolytic and lipolytic activities.

Freeze Drying↗

PubMed1981

[Inhibition of bacterial luminescence by cytochrome P-450 substrates].

The mechanisms of luminescence quenching by various drugs, e.g. dimethylaniline, ethylmorphine, hexobarbital and aminopyrine, which are effective inhibitors of luminescence both in intact cells and in bacterial luciferase, were studied. It was shown that the inhibition of luminescence occurs due to competition of the bacterial luminescence system substrate--aliphatic aldehyde in cytochrome P-450. The functional similarity of the bacterial luminescence system to the microsomal hydroxylation system is postulated.

Aminopyrine↗

PubMed1979