Isolation and characteristics of high-frequency genetic donors of a serotyped strain of Escherichia coli

As a result of crossing cells of donor strainEscherichia coli K-12 (P4X) with serotyped (group 0100) recipient cellsE. coli trp^–lac^–, nine recombinants possessing sex factor and ability to carry out chromosome transfer with high frequency were isolated. The isolated strains of donor cells carry sex factor in the integrated state and retain their membership of serogroup 0100.Patrice Lumumba People's Friendship University, Moscow. Department of Microbiology, Immunology, and Virology, Central Asiatic Pediatric Medical Institute, Ministry of Health of the USSR. Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 79, No. 2, pp. 106–109, February, 1975.     

Effect of Clostridium perfringens type a toxin and metabolic products of Clostridium butyricum on liver lysosomes in vitro

During incubation of the lysosomal fraction of the albino mouse liver withClostridium perfringens type A toxin and also with the toxin and filtrate of a broth culture ofClostridium butyricum, and increase in the specific acid phosphatase activity was observed. The action ofC. perfringer toxin on the lysosomal membrane was potentiated under the influence of metabolic products ofC. butyricum. Potentiation of the action ofC. perfringens toxin on the lysosomes was due to thermostable substances in theC. butyricum filtrate.Department of Microbiology, N. I. Pirogov Odessa Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 8, pp. 181–183, August, 1979.     

Cytopathogenic action of strains of Escherichia coli containing similar heterogenetic antigens of the AB0 type on human cell cultures

The character of interaction between different strains ofEscherichia coli serotype O26 and cells of continuous cultures of human strains HeLa, Tg-33, and RH was studied in vitro. The phenomenon of cytopathogenic action (CPA) of uropathogenic strains ofE. coli containing heterogenetic type O(H) and B antigens on human cell strains with the corresponding isoantigens was detected after interaction for 6 h. The number of dead cells in these cultures was 1.5–3 times greater than their number in control cultures to whichE. coli cells not containing heterogenetic antigens or containing dissimilar heterogenetic antigens of the human AB0 type were added. It is postulated that this phenomenon plays an important role in the development of chronic forms of colibacillary pyelonephritis.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 5, pp. 568–570, May, 1976.     

Enterotoxic activity of living cultures of Shigella sonnei and enterotoxin formation in vivo

The overwhelming majority of virulent strains ofShigella sonnei caused the accumulation of fluid in the lumen of an isolated segment of rabbit small intestine; the fluid contained large quantities of mucus and sometimes blood; the mucous membrane of the segment was hyperemic and had petechial hemorrhages. Avirulent strains ofSh. sonnei as a rule did not cause exudation into the loop of intestine. The sterile and concentrated contents of the intestinal loops of rabbits responding to injection of the virulent strain ofSh. sonnei or a toxigenic strain ofShigella shigae invariably gave a positive reaction in other rabbits. The character of the exudate and the changes in the mucous membrane under these circumstances were indistinguishable from those following injection of living cultures.Microbiological Department, Moscow Research Institute of Epidemiology and Microbiology. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Kosyakov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 12, pp. 703–705, December, 1977.     

Experimental study of the sensitizing activity of Neisseria perflava

The sensitizing activity ofNeisseria perflava isolated from the bronchial mucosa of patients with infectious asthma was studied in experiments on guinea pigs. It was shown that Ovary's passive cutaneous anaphylaxis test and the tracheal chain contraction test can be reproduced withNeisseria antigens. High sensitizing activity ofN. perflava was found compared with two other microorganisms:Klebsiella pneumoniae andStaphylococcus aureus, inhabiting the bronchi of patients with infectious asthma.Allergologic Scientific-Research Laboratory, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 191–193, August, 1977.     

Role of the normal microflora in treatment of the vibro carrier state in germfree rats

Relations betweenVibrio cholerae and certain representatives of the normal human intestinal microflora which, in experiments in vitro were found to be active antagonists, were studied. Experiments were carried out on germfree rats of the Fisher strain. When different combinations and orders of administration of the microorganisms were used, no antagonistic relations were found betweenV.cholerae El-Tor andEscherichia coli M-17,Lactobacillus fermenti, andLactobacillus plantarum. Rats infected with El-Tor vibrio were completely cured of the vibrio carrier state through population of their intestinal tract with the fetal microflora of healthy rats.N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 6, pp. 712–715, June, 1978.     

Changes in the microcirculation during the combined action of clostridium perfringens type a toxin and metabolic products of clostridium butyricum

In poisoning caused by injection ofClostridiumperfringens type A toxin or a mixture of toxin with the filtrate of a culture ofClostridium butyricum, changes in the microcirculation in the mucous membrane of the retrobuccal pouch of golden hamsters were found. The microcirculatory changes took place in two phases. In the first phase vasomotor disturbances were observed, as shown by periodic changes in diameter of the arterial microvessels, and by plasmatization and a decrease in the number of functioning capillaries. The diameter of the veins showed no significant change. The second phase was characterized by persistent disturbances of the microcirculation: slowing of the blood flow in the arterial and venous portions, the appearance of regions of stasis, a retrograde blood flow, and arterial dilatation. The persistent disturbances of the microcirculation following injection of a mixture ofCl. perfringens toxin and filtrate of a broth culture ofCl. butyricum appeared sooner than those in response to injection of the toxin alone.Department of Microbiology, N. I. Pirogov Odessa Medical Institute. Laboratory of Pathophysiology of Extremal States, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. N. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 11, pp. 552–554, November, 1977.     

Immunologic reactivity of (C57BL/6 × A/Sn)F1 mice in mixed Mycoplasma-virus infection

Mixed infection of hybrid mice, highly resistant to Rauscher virus, with this virus andMycoplasma arthritidis was accompanied by progressive inhibition of populations of splenic rosetteforming (REC) and plaque-forming (PFC) cells and led to induction of malignant erythroblastosis, cytologically identical with Rauscher's leukemia. During mixed infection of the hybrid mice withAcholeplasma laidlawii and Rauscher virus the immune response was almost completely suppressed on the 21st day and considerable splenomegaly was observed, but by the 62nd day of infection the RFC and PFC populations and also the weight of the spleens had regained the control level. The possible role of mycoplasmas in the induction and development of Rauscher's leukemia is discussed.N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician O. V. Baroyan.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 9, pp. 327–329, September, 1979.     

Effect of preparations of Clematis fusca on target organs for androgens

During the action of preparations ofClematis fusca Turcz. on the prostate gland and seminal vesicles of castrated rats increased functional activity of these organs was observed, similar to that found under the influence of methyltestosterone. Substances with androgenic action are evidently present in this plant.Department of Pharmacology and Department of Histology, Vladivostok Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 80, No. 7, pp. 60–61, July, 1975.     

Investigation of function of the lactose operon of escherichia coli K-12 under the influence of nonspecific regulators

The possible role of cyclic AMP in the stimulating action of ACTH and hydrocortisone on the lactose operon ofEscherichia coli K-12 was investigated. It was shown that ACTH had no effect on strainsE. coli WZ-78/F'lac (cya₈₅₅) andE. coli CA 8001 (L₁), in which the system of regulation of the function of the lactose operon by cyclic AMP is disturbed. Meanwhile this hormone stimulates the lactose operon in wild-type strains:E. coli 200 PS/F'lac andE. coli 3000. Hydrocortisone stimulates the function of the lactose operon both in the wild-type strainE. coli 3000 and in the mutantE. coli CA 8001 (L₁). It is considered that the stimulating action of ACTH on the lactose operon is mediated through cyclic AMP and that hydrocortisone stimulates the function of the lactose operon independently of cyclic AMP.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 33, No. 6, pp. 744–746, June, 1977.     

Glucose tolerance and insulin sensitivity of rats poisoned with Amanita phalloides

The effect ofAmanita phalloides toxins on glucose tolerance and insulin sensitivity was studied.Amanita toxins were injected intraperitoneally in a dose of LD₅₀ into male albino rats. Amanita toxins were found to disturb glucose tolerance, to increase the utilization of glucose by the tissues, and to make the animals more sensitive to insulin. These effects may be the result of depression of the insulin-activating capacity of the liver and potentiation of the function of the islet-cell apparatus of the pancreas.Department of General Biology, Ternopol' Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR S. N. Golikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 9, pp. 319–321, September, 1978.     

Albino mouse paw edema — A test for estimating Escherichia coli enterotoxin activity

The mouse paw edema test was evaluated as a means of detecting activity ofEscherichia coli (strain P-99) enterotoxins. The paw edema test was shown to be simple, sensitive, and reproducible, and to permit determination of activity of the thermostable and thermolabile enterotoxins and endotoxin. This test is particularly useful for the evaluation of endotoxin preparations in the course of their isolation and purification.Laboratory of Protective Antigens, I. I. Mechnikov Moscow Institute of Vaccines and Sera. Department of Microbiology, Central Postgraduate Medical Institute, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. A. Vershilova.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 150–152, February, 1978.     

Action of a polysaccharide from Salmonella typhi on hematopoietic stem cells

The dynamics of the number of colony-forming units (CFUs) in the spleen and bone marrow of unirradiated F₁(CBA×C57BL) mice was studied after intraperitoneal injection of polysaccharide (PC) fromSalmonella typhi. The method of exogenous colony formation was used. After a single injection of PC the number of CFUs in the bone marrow was increased by 2–2.5 times and in the spleen by 3 times. Repeated (6–9 times) injections of PC were no more effective than a single injection. PC evidently acts as an inducer which, by inducing proliferation of hematopoietic stem cells, maintains this process automatically for a certain period of time.Laboratory of Radiation Immunology, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR G. V. Vygodchikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 79, No. 3, pp. 66–68, March, 1975.     

Changes in cortical electrical activity in poisoning by Clostridium perfringens type a toxin

In cats lightly anesthetized with pentobarbital (15–20 mg/kg) cortical electrical activity was recorded during the development of poisoning by the toxin ofClostridium perfringens type A, injected intramuscularly (100 MLD/kg). Changes in cortical electrical activity occurred in two phases. In the first phase desynchronization of activity, preservation of evoked potentials and changes in the rhythm structure in response to photic stimulation were observed. Desynchronization was not observed after preliminary mesencephalic section (mesencephalic preparation), indicating involvement of the reticular formation in the pathological process and its role in the desynchronization effect. In the second phase cortical electrical activity was deeply inhibited, evoked potentials depressed, and the rhythm reconstruction reaction was disturbed.Departments of Microbiology and Pathological Physiology, N. I. Pirogov Odessa Medical Institute. Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 10, pp. 1192–1198, October, 1976.     

Stimulation of chloramphenicol acetyltransferase synthesis by cyclic AMP in bacterial cell systems

The effect of cyclic 3,5-adenosine monophosphate (cAMP) on production of the enzyme chloramphenicol acetyltransferase (CAT) by whole bacterial cells was studied in strainsEscherichia coli CSH-2/R222 and WZ-78/R222 (cya₈₅₅). CAT synthesis in strainE. coli WZ-78/R222 was shown to have an intensity only half as great as that of strainE. coli CSH-2/R222. The production of CAT by strainE. coli CSH-2/R222 was increased only very slightly by cAMP, but its effect on the production of this enzyme in strain WZ-78/R222 was appreciable.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR, N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 80, No. 10, pp. 65–66, October, 1975.     

Nature of Rec+ revertants isolated from Escherichia coli K-12 cultures with recA- mutations

The nature of Rec⁺ revertants isolated previously from cultures of recombinationally defective strainEscherichia coli K-12 AB 2463 recA13 was studied. With the aid of phage P1 vira the chromosome region of the recA gene in cells of strain JC2915F^- were transduced, after which the recombination capacity of the transductants was determined by crossing with JC158Hfr cells and their resistance to ultraviolet radiation was established. Sensitivity of the transductants to suppressor phages was determined. The Rec⁺ revertants were shown to differ with respect to the recA gene. In some Rec⁺ revertants the Rec⁺ phenotype appeared as the result of a back mutation in this gene from rec^- to rec⁺, whereas in other revertants the Rec⁺ phenotype was due to indirect suppression.Department of Biology and General Genetics, Patrice Lumumba Peoples' Friendship University, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. M. Zhdanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 12, pp. 1487–1488, December, 1976.     

The effect of venous blood stream cooling on survival of bacterially infected rabbits

Summary The effect of physical cooling on the mortality rate of rabbits infected withPasteurella multocida was investigated. Rabbits were colled for 48 hours after bacterial injection by passing cold fluid through small hollow metal cuffs which had been surgically implanted around the abdominal vena cavae of rabbits. The average body temperatures of the rabbits during the 24-hour period after the intravenous injection of livePasteurella multocida was 40.92±0.20°C in control rabbits and 38.98±0.71°C in cooled rabbits. 90% of physically cooled rabbits survived compared with 46% of control rabbits 48 hours after bacterial injection, suggesting that thermoregulatory effector mechanisms involved in cold defense may enhance survival.     

On antigenic properties of genetic recombinants of Escherichia coli serotypes

A study of conjugation between typed strains ofEscherichia coli belonging to different O serogroups and of conjugation between typed and untyped strains showed that the genetic determinant controlling synthesis of the O100 antigen is closely linked with the histidine locus. Among recombinants isolated from crosses between typedE. coli cells some were found to have a different serotype from that of the donor and recipient cells.Department of Biology and General Genetics, Patrice Lumumba Peoples' Friendship University. Scientific-Research Laboratory of Experimental Immunology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 181–182, August, 1977.     

Role of substrate inducers in the mechanism of action of cortisone on β-galactosidase activity in various strains of escherichia coli K-12 and in rat liver

A comparative study of the effect of cortisone on -galactosidase synthesis in strains ofEscherichia coli K-12 with an induced (E. coli 200 PS/F lac), a constitutive (E. coli ML-308), and a superrepressed (E. coli 2000 i^S) type of enzyme synthesis and in rat liver cells showed that the hormone itself has no derepressive effect. In all cases an increase in -galactosidase synthesis takes place only in the presence of the specific substrate inducers. It is suggested that the principal stage in the mechanism of action of cortisone on the lactose operon ofE. coli and on enzyme production in rat liver cells is the preliminary derepression of regions of the genome through substrate inducers.Department of Biology and Fundamentals of Genetics, Central Postgraduate Medical Institute, Moscow. Department for the Study of the Molecular Mechanisms of Drug Addiction, N. I. Pirogov Second Moscow Medical Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 1, pp. 24–25, January, 1977.     

Immunogenic and sensitizing properties of sexual recombinants of Escherichia coli AND Shigella flexneri

Summary The genetic sexual recombinants ofS. flexneri andE. coli in the process of immunization of animals confer immunity only to the recombinant forms, in a lesser degree to the recipient homo- and heterologous strains of Shigella, and fail to afford protection againstE. coli Hfr H and other types of dysentery bacteria. A donor ofE. coli Hfr H contributes to the formation of a strictly specific immunity failing to protect animals either against sexual hybrids or against Shigella. A living culture ofE. coli Hfr H and genetic recombinants possesses marked allergie qualities with regard to various biological models: rabbits, albino mice, guinea pigs.Sensitization is devoid of any strict specificity and has a cross para-allergic character. Genetic hybrids andE. coli donors are an important pathogenetic factor supplementing the allergic link in the development of bacterial dysentery.Department of Microbiology, Vladivostok Medical Institute (Presented by Active Member of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov). Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 62, No. 7, pp. 74–78, July, 1966.