Necessity of genes acting in central metabolism, envelope biosynthesis, and cell division for L. monocytogenes growth. Heat maps illustrating the necessity of selected genes and pathways for growth of L. monocytogenes. Where genes were aggregated according to their pathways, their necessity for growth is expressed as the number of genes required for growth divided by the number of all genes in this particular pathway. Necessity for growth is shown for standard growth conditions (BHI broth) and during growth in J774 macrophages (infection).