Difference between revisions of "Part:BBa K771305"

Revision as of 14:59, 27 September 2012

TesA with Membrane Anchor 2 (without MS2)

TesA is a cytoplasmic mutant of the periplasmic thioesterase. It is capable of releasing free fatty acids, preventing the fatty acids from being directly harnessed for phospholipid biosynthesis.

Membrane anchor 2 without MS2 is described at BBa_K771007.

TesA is linked to C terminal of Membrane anchor 2 without MS2 by Flexible Linker 3(Fl3).

Fatty acid Biosynthetic Pathway

TesA involves in the biosynthesis of fatty acids in E.coli. The biosynthesis pathway is shown as below:

Fatty acid biosynthesis pathways in E.coli, showing the role of FabG, FabZ, FabI and TesA.

The E. coli fatty acid synthesis is initiated when holo-ACP, NADPH and NADH, acetyl-CoA and malonyl-CoA undergo condensation and subsequent reduction to form butyryl-ACP. These reactions are catalyzed by the malonyl-CoA:ACP transacylase FabD, the ketosynthase FabH, the NADPH-dependent ketoreductase FabG, either the dual-function dehydratase/isomerase FabA or the monofunctional dehydratase FabZ, and the NADH-dependent enoyl reductase FabI. Then the butyryl-ACP is extended via 5-7 rounds of analogous reactions to produce a C14 to C18-ACP either fully saturated or monounsaturated. These extension cycles are catalyzed by either the ketosynthase FabB or FabF in collaboration with FabD, FabG, FabA or FabZ, and FabI. Finally, the full-length fatty acid is released from the corresponding fatty acyl-ACP via hydrolysis by C16-specific thioesterase,TesA.

Result

The introduce of TesA with Membrane Anchor 2 (without MS2) alone can leads to 50% increase in fatty acids.

Fatty acid biosynthesis pathways in E.coli, showing the role of FabG, FabZ, FabI and TesA.

The cooperation of TesA with Membrane Anchor 2 (without MS2), FabG with Membrane Anchor 3, FabZ with Membrane Anchor 4, FabI with Membrane Anchor 4(without VVD) could significantly enhance the production of fatty acid by 9 fold compared with enzymes without membrane anchor.

Fatty acid biosynthesis pathways in E.coli, showing the role of FabG, FabZ, FabI and TesA.

Fatty acid biosynthesis pathways in E.coli, showing the role of FabG, FabZ, FabI and TesA.

Sequence and Features