Chapter 2 Lipid metabolism in procrayotes

This chapter provides an overview of the regulatory mechanisms of lipid metabolism in prokaryotes. The main advantage that bacteria offer over other systems is the use of the genetic approach to manipulate the experimental system. In E. coli, phospholipids are synthesized exclusively for use in the biogenesis of membranes, and there does not appear to be any significant alternative fate for these lipids. The chapter indicates that the mechanisms that operate to produce the observed distribution of phospholipid polar head groups have not been uncovered, and the details of how phospholipid and macromolecular biosynthesis are coordinated during normal growth and nutritional stress remain to be established. The regulatory point that controls the divergence of 20% of the acyl-acyl-carrier protein (ACP) to lipid A biosynthesis rather than to phospholipid production is also a mystery. The genetic approach will continue to be an important tool for this, and recent advances in genetic-cloning procedures have begun to have a profound effect on the understanding of both the biochemistry and physiology of E.coli.