Threonine synthesis pathway. Enzymes surrounded by a thick gray box were shown to be horizontally transferred from Bacteria (see main text). Metabolites – I: glycine; II: threonine; III: phosphohomoserine; IV: homoserine; V: aspartate 4-semialdehyde; VI: 4-aspartyl-phosphate; VII: L-aspartate. Enzymes – 220.127.116.11: threonine aldolase; 18.104.22.168: aspartate kinase; 22.214.171.124: aspartate-semialdehyde dehydrogenase; 126.96.36.199: homoserine dehydrogenase; 188.8.131.52: homoserine kinase; 184.108.40.206: threonine synthase. Abbreviations as for Figure 1.
Alves et al. BMC Evolutionary Biology 2013 13:190 doi:10.1186/1471-2148-13-190