Schematic drawing the outer membrane of a Gram-negative bacterium. The plasma membrane is an exceptionally dynamic structure in bacteria which mediates permeability , transport , secretion and energy generation . In terms of pathogenesis of a bacterium, it is absolutely dependent upon the integrity and function of its plasma membrane. The membrane might be responsible for secretion of toxins, resistance to antimicrobial agents, tactic responses or sensing other environmental signals to turn on or off genes for virulence. Biologically, endospores are a fascinating type of cell.
Endospores exhibit no signs of life, being described as cryptobiotic.
They are probably the most durable cell produced in nature . Although cryptobiotic, they retain viability indefinitely such that under appropriate environmental conditions, they germinate back into vegetative cells. Both genera contain pathogens, and the endospores produced by these bacteria invariably play some role in the toxicity, transmission or survival of the pathogen .