TABLE 1.

Comparison of HlyA and SheAa

PropertyCharacteristic of:
HlyASheA
Molecular weight∼110 kDa∼34 kDa
Pore formation5-20 molecules, Ca2+ dependent1,000-2,000 molecules, Ca2+; independent
Pore size1.5-2.5 nm2.5-3 nm
Secretion systemType 1Membrane vesicules?
GenesChromosome (human pathogens), plasmid (animal pathogens), requires HlyB, HlyD, and TolCChromosome
GC content∼40%∼40%
Target cellsRBC, granulocytes, monocytes, lymphocytes, endothelial cells, renal epithelial cellsRBC, macrophages, monocytes
EffectsCytolytic, cytotoxic, cytokine production, leukotriene production, superoxide productionCytolytic, cytotoxic
  • a RBC, red blood cells.