9 Enzymology of Bacterial Lysine Biosynthesis

Lysine is an essential amino acid in the mammalian diet, but can be synthesised de novo in bacteria, plants and some fungi (Dogovski et al., 2009; Hutton et al., 2007). In bacteria, the lysine biosynthesis pathway, also known as the diaminopimelate (DAP) pathway (Fig. 1), yields the important metabolites meso-2,6-diaminopimelate (meso-DAP) and lysine. Lysine is utilised for protein synthesis in bacteria and forms part of the peptidoglycan cross-link structure in the cell wall of most Gram-positive species; whilst meso-DAP is the peptidoglycan cross-linking moiety in the cell wall of Gram-negative bacteria and also Gram-positive Bacillus species (Burgess et al., 2008; Mitsakos et al., 2008; Voss et al., 2010) (Fig. 1).