PYOCYANIC STICK

From Big Medical Encyclopedia

PYOCYANIC STICK (Pseudomonas aeruginosa) — type-species of bacteria of the family Pseudomonas of the Pseudomonadaceae family.

Page of the item it is eurysynusic in the nature: it is found in the soil, water, went. - kish. path of the person and nek-ry animals. Page of the item — an opportunistic microorganism, the activator intrahospital infection (see), and strikes persons with reduced natural immunity; its nek-ry strains have phytopathogenic properties.

The village of the item — a gram-negative direct mobile stick of 0,5 in size — 0,8 X 1,5 — 3,0 microns, has one polar flagellum. In a smear is located with single cells, couples or short chains. The page of the item represents an obligate aerobe (see. Aerobes ), electron sink is molecular oxygen. Contents guanine + tsitozin in DNA makes the 67th pier. %. For S.'s growth the item is enough one organic compound (e.g., citrate) as source of carbon and energy. Optimum temperature of an incubation 37 °, can grow at t 42 °. On the dense environment forms rough colonies with the uneven edge, metallic luster and a characteristic smell reminding aroma of a jasmine.

In comparison with other gram-negative bacteria S. of the item is biochemical poorly active. Sharply positive is characteristic of it oksidazny reaction (see), and also products of two pigments: the green flyuorestsein diffusing in a medium and water soluble and in chloroform of pyocyanine — the fenazinovy connection having blue coloring in neutral and alkaline condition, and in acid — red. Nek-ry cultures of S. of the item form additional pigments: brown-red piorubin, red erythrogene, black melanogen; 10 — 18% of strains of S. of the item are deprived of ability to chromogenesis.

The village of the item develops biologically active products, to-rye it is possible to consider factors of its pathogenicity: the exotoxins A, B and C having high toxicity; hemolysins, including a phospholipase With; collagenase, elastase and other proteases; enterotoxin, leukocidin, etc. S. the item produces piotsina (see. Bakteriotsinogeniya ), it is steady against the majority of antibiotics. Items aminoglycosides (gentamycin, Tobramycinum, amikacin), karbenitsillin, polymyxins and a combination of aminoglycosides with karbenitsilliny are most active concerning S. But the number of strains of S. of the item steady against these drugs, gradually increases. The page of the item shows sensitivity to such antiseptic agents as 0,5% solution of chloroamine, 3% solution of hydrogen peroxide, 2% solution of phenol (carbolic to - you), 0,1% solution of a sulfokhlorantin.

At S.'s allocation the item from patol. material use simple mediums (a beef-extract agar, a beef-extract broth, a blood agar), and also the selection environments, to-rye contain the drugs suppressing growth of foreign microflora (acetamide, nalidixic to - that, nitrofurans, tetraethyl-diamino-triphenyl-carbohydride sulfate, etc.). At specific identification of strains characteristic signs for S. items consider recovery of nitrate to gaseous nitrogen, fluidifying of 15% gelatin, positive takes at oxidation of glucose, a mannitol, xylose and sucrose, negative at oxidation, lactoses, maltoses, sorbite, an inositol, an adonit, dulcite, salicin, and also lack of egg and vitelline reaction.

The intraspecific differentiation of S. of the item which is carried out in the epidemiological analysis is carried out by means of phages, piotsin and diagnostic immune serums (see. Identification of microbes ).

See also Pyogenic bacteria .


Bibliography: Stanislavsky E. S. and To about l to e r I. I. Pyocyanic infection, M., 1978; Bailey W. R. and. Scott E. G. Diagnostic microbiology, St Louis, 1970; Bergey’s manual of determinative bacteriology, ed. by R. E. Buchanan a. N. E. Gibbons, p. 217, Baltimore, 1974; Liu P. V. Extracellular toxins of Pseudomonas aeruginosa, J. infect. Dis., v. 130, suppl., p. S 94, 1974; Resistance of Pseudomonas aeruginosa, ed. by M. R. Brown, L., 1975.


H. S. Akatova.

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