title: The characteristics of a variant strain of Brucella melitensis Rev 1.
abstract: Circumstantial evidence is presented for the occurrence of a variant of a vaccine strain of B. melitensis Rev 1, designated "FSA" (foreign South African). FSA resembles Rev 1 in its reactions to penicillin and streptomycin but reacts closer to a field strain of B. melitensis as regards dye (thionine and basic fuchsin) sensitivity and colony size. Although colonies of Rev 1 were consistently smaller than other B. melitensis strains, their size was 0,75 mm as opposed to the 1-2 mm reported in the literature, while B. melitensis 16M colonies were 1,25-1,5 mm as opposed to the 3-4 mm previously reported. Rev 1 was found to be urease positive, unless a test of low sensitivity was applied.
authors.affiliation: Veterinary Research Institute, Onderstepoort.
authors.forename: P M
authors.initials: PM
authors.lastname: Pieterson
authors.forename: B
authors.initials: B
authors.lastname: Gummow
authors.forename: S
authors.initials: S
authors.lastname: Pefanis
authors.forename: C G
authors.initials: CG
authors.lastname: Venter
authors.forename: S
authors.initials: S
authors.lastname: Herr
mesh_terms: D002002:Brucella / Q000145:classification* / Q000302:isolation & purification; D013019:South Africa