Fig 1.

Mevalonate (MVA) and 2C-methyl-d-erythritol-4-phosphate (MEP) polyisoprene substrate provision pathways. Enzymes that have been targeted during the course of metabolic engineering studies for improved paclitaxel intermediate titers are shown in boxes. Specific E. coli enzyme designations are in parentheses. AACS, acetoacetyl-CoA synthase; AACT, acetoacetyl-CoA thiolase; AACL, acetoacetyl-CoA ligase; HMGS, hydroxymethylglutaryl (HMG)-CoA synthase; HMGR, HMG-CoA reductase; MVK, mevalonate kinase; PMK, phosphomevalonate kinase; PMD, mevalonate pyrophosphate decarboxylase; IDI, isopentenyl diphosphate isomerase; IPP, isopentenyl diphosphate; DMAPP, dimethylallyl diphosphate; G3P, glyceraldehyde-3-phosphate; DXS, 1-deoxy-d-xylulose 5-phosphate (DXP) synthase; DXR, DXP reductase; MEP, 2-C-methyl-d-erythritol 4-phosphate; CMS, 4-diphosphocytidyl-2-C-methyl-d-erythritol (CDP-ME) synthase; CMK, CDP-ME kinase; CDP-MEP, CDP-ME 2-phosphate; MCS, 2C-methyl-d-erythritol 2,4-cyclodiphosphate (MEcPP) synthase; HDS, 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate (HMBPP) synthase; HDR, HMBPP reductase.