The least numbers of cultural and biochemical properties to identify Bacillus anthracis and to rule out other closely related Bacillus species were determined. The specificity of monoclonal antibody(MAb) to vegetative cell surface antigens of B.
anthracis Sterne 34-F2 was evaluated by indirect flulorecent antibody(IDF) staining and Ouchterlony double diffusion test(DDT).
Seven strains of B. anthracis confirmed in this study by demonstration of two virulence-related plasmids (pXO1 and pxo2), capsule formation and pathogenicity to mouse were distinguished from six strains of other Bacillus species by a combination
of
five
cultural and biological properties such as nonhemolysis, nonmotility, susceptibility to penicillin, TSI reaction(A/A), and linea liquefaction in gelatin agar, whereas all strains of closely related Bacillus species tested were ruled out by
additional
properties of utilization of citrate, nonhydrolysis of starch and nonproduction of lecithinase.
Cell wall of B. anthracis Sterne 34-F2 antigens were used to immunize BALB/c mice and to develop MAb to vegetative cell surface antigens, Five hybridomas selected during the study produced IgG1 By IFA analysis with MAbs followed by goat
anti-mouse
IgG
labeled with FITC, both all encapsulated and nonencapsulated vegetative cells of B. anthracis strains tested, grown ambiently on human blood agar, were stained intensely, whereas none of the strains of other Bacillus species was stained. The five
MAbs
also reacted specifically with crude extracts of B. anthracis strains tested by DDT, whereas none of the MAbs reacted with antigens of closely related Bacillus species strains tested.
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