. Estimation of toxigenic properties B. Estimation of proteolytic properties
C. Estimation of urease activity
D. Estimation of cystinase activity
E. Estimation of ability to decompose starch
20. Pure culture of microorganisms was obtained from pharynx of a child with suspected diphtheria. Morphologic, tinctorial, cultural, and biochemical properties of the microorganisms were studied and revealed to be characteristic of diphtheria agents. What investigation should be additionally performed to make a conclusion, that these microorganisms are pathogenic diphtheria bacilli?
A. Determine toxigenic properties B. Determine proteolytic properties
C. Determine urease activity D. Determine cystinase activity
E. Determine amylolytic activity
21. In order to determine toxigenicity of diphtheria bacilli a strip of filter paper impregnated with antitoxic diphtheria serum was put on the dense nutrient medium. There were also inoculated a microbial culture under examination and a strain that is known to be toxigenic. If the microbial culture under examination produces exotoxin, this will result in formation of:
A. Precipitin lines B. Haemolysis zones
C. Zones of diffuse opacification
D. Zones of lecithovitellinous activity E. Precipitin ring
22. In order to estimate toxogenicity of diphtheria agents obtained from patients the cultures were inoculated on Petri dish with nutrient agar on either side of a filter paper strip that was put into the centre and moistened with antidiphtheric antitoxic serum. After incubation of inoculations in agar the strip-like areas of medium turbidity were found between separate cultures and the strip of filter paper. What immunological reaction was conducted?
A. Precipitation gel reaction B. Coomb’s test
C. Agglutination reaction
D. Rings precipitation reaction E. Opsonization
23. When examining a child the dentist found the deposit on both tonsils and suspected atypical form of diphtheria. A smear was taken, and after the nutrient media inoculation the toxicity of the isolated pure culture was determined. What reaction was used to determine the toxigenicity of the isolated strain of diphtheria bacillus?
A
