Figure 2.

Overview of transport reactions captured in the human metabolic reconstructions. The transporter content for the major metabolite classes captured by Recon 2 and Recon 1 are shown and compared. (A) Quantitative assessment of the transport reactions present in Recon 1 (Duarte et al., 2007) and Recon 2 (Thiele et al., 2013). (B) Classification of the transport reactions as per the major class of metabolite transported. (C) Literature support for the transport reactions present in Recon 2. (D) The metabolites were divided into ten metabolite classes and their major transport mechanisms, as captured in Recon 2, are shown. The blood groups comprise the major glycolipids. (E) Comparison of the transport reactions present in Recon 1 and Recon 2. The increased information included and expanded the scope of Recon 2, over Recon 1, resulting in better transporter coverage for the amino acid, carbohydrate, and vitamin classes, while significant work is needed for the lipid class. The following symbols are used: ⋆⋆⋆, good coverage; ⋆⋆, intermediate coverage; ⋆, needs significant effort.