Transporters are shown in the cell on the right, and grouped by substrate specificity: multidrug and peptide exporters (red), carbohydrates (yellow), cations (blue), anions and amino acids (green), nucleosides, purines and pyrimidines (purple), and other substrates (white). Question marks indicate uncertainty in the identity of the genes, direction of transport, or substrate. Permeases are drawn as rectangles, porins are drawn as cylinders, ATPases are ovals overlapping rectangles, other transporters are drawn as ovals, and ABC transporters elements are depicted as circles for nucleotide-binding proteins, diamonds for membrane-spanning permeases and rectangles for the substrate-binding proteins. The 20 hypothetical ABC transporters for which no substrate could be predicted are not shown on the figure. Enzyme names are green, and names of those enzymes we expected to find but could not identify are italicized. The glycolytic pathway leading to lactate is shown along with the pathway for glutamine to nitrogen containing compounds (Additional material on carbohydrate metabolism is in Supplementary Material #3) The ATP consumption and production values listed are for monosaccharides; ATP values for disaccharide catabolism are in parentheses. The choline-binding proteins are autolysin (LytA), endo-beta-N-acetylglucosaminidase (LytB), a surface protein involved in adherence and IgA inactivation (CbpA), a putative lactoferrin binding protein (PspA), and several surface proteins unknown function (CbpD, PcpA, PcpC, PcpC1).

The electron micrograph is provided by Dr. Alexander Thomaz, from "Streptococcus pneumoniae Molecular Biology and Mechanisms of Disease" Mary Ann Liebert Inc. Publishers, NY , 2000. This figure used with permission from Hoskins, et al. 2001 The genome of the bacterium Streptococcus pneumoniae strain R6. J. Bacteriol. 183:5509-5517. Copyright © American Society for Microbiology. All Rights Reserved