Some bacteria use the citric acid cycle intermediate, α-ketoglutarate, plus acetyl-CoA, as the starting point for lysine biosynthesis. The first part of this biosynthetic pathway uses the same chemical strategy found in the citric acid cycle. Propose a four-step pathway for the conversion of α-ketoglutarate to 2-oxoadipate. Draw the three missing intermediates, and indicate the chemistry involved in each reaction. Include any cofactors that you think might be required for specific steps.

COO COO 2 3 CH CH COO -Ketoglutarate CH acetyl-CoA HS-CoA COO 2-oxoadipate