H-serotyping
The study of flagellate H serotypes obtained from fecal samples was
used. For this purpose, an agglutination method was used; the study was
performed on a slide according to the generally accepted recommendations
(De Barjac & Frachon, 1990). The test was performed by referring the H
antiserum against B. thuringiensis H-serotypes 1-58. Hence,
motile isolates were termed non-typeable as non-reactive against the
reference H antiserum; isolates without flagellation were found; the
presence of a strong degree of autoagglutination was considered as well.
Bacterial serotypes were identified according to the nature of their
flagellate H-antigens. However, antisera prepared to the H antigens may
share several common antibodies. Monospecific antisera containing one
particular antibody were prepared by saturating aliquots of basal
antisera with selected antigens one at a time and removing undesirable
antibodies by centrifugation after completing the precipitation
reaction. Such monospecific antisera allow the detailed typing bacteria
with common antigenic subfactors as serotypes.