21. Zingiberene is formed in the isoprenoid pathway from farnesyl pyrophosphate ( FPP ). 22. The reaction uses thiamine pyrophosphate in order to link the two pyruvate molecules. 23. Phosphosphomevalonate decarboxylase through a concerted decarboxylation reaction affords isopentenyl pyrophosphate ( IPP ). 24. They couple pyrophosphate hydrolysis or synthesis to Na + or H + pumping. 25. The cofactor necessary for this step to occur is thiamin pyrophosphate ( TPP ). 26. GPP then loses the pyrophosphate group to form the resonance-stable geranyl cation. 27. All PRTases involve the displacement of pyrophosphate in PRPP by a variety of nucleophiles. 28. Moreover, the Lys522 sidechain also moves to neutralize the negatively charged pyrophosphate group. 29. The energy required for this linkage comes from the hydrolysis of a pyrophosphate molecule. 30. Thiamine pyrophosphate cofactor in yellow and xylulose 5-phosphate substrate in black . ()
