Colicin with membrane systems

Figure 13 summarizes the present state of knowledge regarding interactions of siderophores, phages, and colicins with membrane systems in the enteric bacteria. Over the eons of evolutionary time, noxious agents have acquired the capacity to exploit these receptors as a means of penetrating the cell envlope. It would be important to ascertain if this analogy extends to plant and animal virus receptors. 

Accordingly, this chapter deals mainly with some of the very recent advances in knowledge of iron transport systems in enteric bacteria. I review critically and place in historic perspective current understanding of the competition phenomenon between phages, colicins, and sidero-phores for outer membrane receptors, the resistance to certain colicins imparted by iron, and, finally, the mechanism of siderophore-mediated iron uptake. 

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