Effects of Growth Stage on the Characterization of Enterotoxin A-Producing -Derived Membrane Vesicles.

Virulence factors, such as staphylococcal enterotoxin A (SEA), are contained within membrane vesicles (MVs) in the cell membrane of . In this study, the effects of the growth stage on quantitative and qualitative changes in the components contained in the MVs of SEA-producing strains were examined. Changes in the expression levels of genes were examined at each growth stage; phenol-soluble modulin (PSM) gene reached a maximum after 8 h, and the expression of cell membrane-related genes was decreased after 6 h.

Predominant Shift of Different P44-Expressing Anaplasma phagocytophilum in Infected HL-60, THP-1, NB4, and RF/6A Cell Lines.

Anaplasma phagocytophilum, an agent of human granulocytic anaplasmosis, is an obligatory intracellular bacterium that dominantly produces P44 outer membrane proteins encoded by the p44/msp2 multigene family, which are major antigens for serodiagnosis. However, A. phagocytophilum antigens from cultures with different cell lines seem to have varying reactivities with sera.