An in vivo ¹⁵N NMR Study of Bacterial Cell Walls

Abstract

Bacterial cells, because of their relatively simple organization, have proved to be useful model systems for studying how the structure and function of cellular organelles are determined by the course of their biosynthesis. Although the sequence of the biochemical events leading to the assembly of cellular structural components determine to a large extent function and supramolecular structure, the physicochemical properties of the biopolymers themselves might also contribute to shape and function (1). Less is known about the in vivo physicochemical properties of biopolymers, than about their biosynthesis. An understanding of the three-dimensional structures and molecular dynamics of biopolymers is often required to bridge the gap between biochemical information on the one hand, and the structure of a cellular organelle, as revealed by electron microscopy, on the other. An example is the expression of the morphogenetically determined shapes of bacteria. The shape of a bacterial cell is maintained by the rigid peptidoglycan layer in its cell wall (2). It was once believed that correlations could be made between the shapes of bacteria and the chemical composition of the peptidoglycan layer (2).