Image Based Question-65783

The pathogenecity of Trophozoite shown in the picture below is indicated by ?

A. Isoenzyme pattern.

B. Size.

C. Nuclear pattern.

D. ELISA test.

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Correct Answer » A Explanation

The pathogenecity of Entamoeba histolytica is indicated by Isoenzyme pattern.

Zymodene

• There are distinct invasive and noninvasive strains of E. histolytica. These strains vary according to their isoenzyme patterns (zymodemes).

• E. histolytica strains have 22 zymodemes of these 10 zymodemes are invasive and 12 are noninvasive.

• Zymodemes of E. histolytica are identified according to the electrophoretic mobility of 4 enzymes.

1. L-malate : NADP+ Oxidoreductase
2. Phosphoglucomutase (PGM) → most important
3. Glucose-phosphate isomerase
4. Hexokinase

• Electrophoresis of PGM can show one or more of the 4 bands : a, 13, y and 5. Strains of E. histolytica showing, an absence of a-band together with the presence of 13 band are virulent i.e., invasive.