The Role of Poles in the Growth Strategy of Bacteria

Abstract

As the additional cytoplasm is formed, it must be encased by a larger cell wall, and therefore, wall growth is imperative. For both cocci and rods, the extant poles are rigid and inert and serve as geometric support for cell expansion. For rods, much of the cell growth is accommodated by cylindrical elongation. Critically, the existing poles are the support for maintaining the cylindrical elongation at a constant radius. For cocci the only means of enlargement is division; i.e., the formation of a septum and its splitting and bulging, which also depends on the extant poles having a constant radius. This process leads to the new poles for the two daughters and to the accommodation of more cytoplasm. Just how the metabolism of various parts of the wall is controlled is important, but not fully clear at present.