The free membranous
material called “FMM” was separated by SDS-PAGE,
and proteins with molecular masses of 84, 25–30, 22, and
18 kDa were observed. Two years later, Gamazo et al.
obtained OMVs from B. ovis and B. melitensis. The electrophoretic
profiles of purified OMVs were compared with
hot saline extract of unlysed cells and showed proteins with
similar masses in both species