2xt6

Structural highlights

Function

KGD_MYCS2 Shows three enzymatic activities that share a first common step, the attack of thiamine-PP on 2-oxoglutarate (alpha-ketoglutarate, KG), leading to the formation of an enamine-thiamine-PP intermediate upon decarboxylation. Thus, displays KGD activity, catalyzing the decarboxylation from five-carbon 2-oxoglutarate to four-carbon succinate semialdehyde (SSA). Also catalyzes C-C bond formation between the activated aldehyde formed after decarboxylation of alpha-ketoglutarate and the carbonyl of glyoxylate (GLX), to yield 2-hydroxy-3-oxoadipate (HOA), which spontaneously decarboxylates to form 5-hydroxylevulinate (HLA). And is also a component of the 2-oxoglutarate dehydrogenase (ODH) complex, that catalyzes the overall conversion of 2-oxoglutarate to succinyl-CoA and CO(2). The KG decarboxylase and KG dehydrogenase reactions provide two alternative, tightly regulated, pathways connecting the oxidative and reductive branches of the TCA cycle.^{[1] [2]}

References

1. ↑ O'Hare HM, Duran R, Cervenansky C, Bellinzoni M, Wehenkel AM, Pritsch O, Obal G, Baumgartner J, Vialaret J, Johnsson K, Alzari PM. Regulation of glutamate metabolism by protein kinases in mycobacteria. Mol Microbiol. 2008 Dec;70(6):1408-23. doi: 10.1111/j.1365-2958.2008.06489.x., Epub 2008 Oct 17. PMID:19019160 doi:http://dx.doi.org/10.1111/j.1365-2958.2008.06489.x
2. ↑ Wagner T, Bellinzoni M, Wehenkel A, O'Hare HM, Alzari PM. Functional plasticity and allosteric regulation of alpha-ketoglutarate decarboxylase in central mycobacterial metabolism. Chem Biol. 2011 Aug 26;18(8):1011-20. PMID:21867916 doi:10.1016/j.chembiol.2011.06.004
3. ↑ Wagner T, Bellinzoni M, Wehenkel A, O'Hare HM, Alzari PM. Functional plasticity and allosteric regulation of alpha-ketoglutarate decarboxylase in central mycobacterial metabolism. Chem Biol. 2011 Aug 26;18(8):1011-20. PMID:21867916 doi:10.1016/j.chembiol.2011.06.004