title: Identification of heterogeneity in human isolates of Giardia lamblia by isoenzyme studies.
abstract: Electrophoretic mobility patterns of six enzymes, viz. alkaline phosphatase E.C. 3.1.3.1., acid phosphatase E.C. 3.1.3.2., malic enzyme E.C. 1.1.1.40., phosphoglucomutase E.C. 2.7.5.1., isocitrate dehydrogenase E.C. 1.1.1.42., glucose-6-phosphate dehydrogenase E.C. 1.1.1.49 of two axenically cultured human Giardia lamblia isolated from India (PD-1 and PD-2) and one strain from Portland, Oregon, USA (P-1) were compared using polyacrylamide gel electrophoresis (PAGE). Based on the difference in the mobility patterns of the enzymes phosphoglucomutase, isocitrate dehydrogenase and malic enzyme, the PD-1 and PD-2 isolates appeared to be quite different from P-1. In the present study, the isocitrate dehydrogenase and alkaline phosphatase enzymes were used for the first time for differentiation of Giardia isolates. In the case of PD-1, two alkaline phosphatase bands could be seen whereas only one band was observed in PD-2 and P-1. Thus, the three strains could be grouped into three different zymodemes. These findings reveal the significant heterogeneity in G. lamblia isolates both from widely separated areas and within a single region. Heterogeneity among G. lamblia strains may explain the variable clinical manifestations, host response and treatment efficacy characteristic of human giardiasis.
authors.affiliation: Department of Parasitology, National Institute of Cholera and Enteric Diseases, Calcutta, India.
authors.forename: P
authors.initials: P
authors.lastname: Chaudhuri
authors.forename: A
authors.initials: A
authors.lastname: De
authors.forename: A
authors.initials: A
authors.lastname: Bhattacharya
authors.forename: S C
authors.initials: SC
authors.lastname: Pal
authors.forename: P
authors.initials: P
authors.lastname: Das
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis; D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D005872:Giardia / Q000145:classification* / Q000201:enzymology; D005873:Giardiasis / Q000469:parasitology*; D005954:Glucosephosphate Dehydrogenase / Q000032:analysis; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000032:analysis; D007527:Isoenzymes / Q000032:analysis*; D008291:Malate Dehydrogenase / Q000032:analysis; D010733:Phosphoglucomutase / Q000032:analysis
chemical_list: D007527:Isoenzymes; D008291:Malate Dehydrogenase; D007521:Isocitrate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D010733:Phosphoglucomutase