The Bacteriocins in Nature

Abstract

We have dealt at some length with what is known of the genetic characteristics of bacteriocinogeny and the lethal action of bacteriocins. Some of the phenomena we have discussed may appear bizarre, for instance the “lethal synthesis” discussed in Chap. 4 or the killing of a cell by a single protein molecule adsorbed to its exterior surface, discussed in Chap. 5. We can ask ourselves two general questions in this circumstance: what part do these phenomena play in the ecology of bacteria ? and how did such a situation ever arise? Of course, there is yet much to be learnt about bacteriocins and it may seem early to speculate in fields where direct experimental evidence is effectively lacking. However, these are very interesting questions, and in this chapter we shall talk around them, knowing that we cannot hope to find a definitive answer. Because the colicins are so much better understood as a group than any other group of bacteriocins, we will largely confine our discussion to them. It is obvious that much will be equally applicable to many other groups of bacteriocins but sufficient is now known of two bacteriocins — megacin A-216 and enterococcin 1-X14 to suggest that they are very different and little of our discussion will be applicable to them.