Structural highlights
4wuo is a 2 chain structure with sequence from Thermus thermophilus HB8. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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Method: | X-ray diffraction, Resolution 2.05Å |
Ligands: | , , , , , |
Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
LEU3_THET8 Catalyzes the oxidation of 3-carboxy-2-hydroxy-4-methylpentanoate (3-isopropylmalate) to 3-carboxy-4-methyl-2-oxopentanoate. The product decarboxylates to 4-methyl-2 oxopentanoate.[HAMAP-Rule:MF_01033]
Publication Abstract from PubMed
The mutant E270A of Thermus thermophilus 3-isopropylmalate dehydrogenase exhibits largely reduced ( approximately 1%) catalytic activity and negligible activation by K(+) compared to the wild-type enzyme. A 3-4kcal/mol increase in the activation energy of the catalysed reaction upon this mutation could also be predicted by QM/MM calculations. In the X-ray structure of the E270A mutant a water molecule was observed to take the place of K(+). SAXS and FRET experiments revealed the essential role of E270 in stabilisation of the active domain-closed conformation of the enzyme. In addition, E270 seems to position K(+) into close proximity of the nicotinamide ring of NAD(+) and the electron-withdrawing effect of K(+) may help to polarise the aromatic ring in order to aid the hydride-transfer.
Glutamate 270 plays an essential role in K(+)-activation and domain closure of Thermus thermophilus isopropylmalate dehydrogenase.,Graczer E, Pallo A, Olah J, Szimler T, Konarev PV, Svergun DI, Merli A, Zavodszky P, Weiss MS, Vas M FEBS Lett. 2015 Jan 16;589(2):240-5. doi: 10.1016/j.febslet.2014.12.005. Epub, 2014 Dec 10. PMID:25497013[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Graczer E, Pallo A, Olah J, Szimler T, Konarev PV, Svergun DI, Merli A, Zavodszky P, Weiss MS, Vas M. Glutamate 270 plays an essential role in K(+)-activation and domain closure of Thermus thermophilus isopropylmalate dehydrogenase. FEBS Lett. 2015 Jan 16;589(2):240-5. doi: 10.1016/j.febslet.2014.12.005. Epub, 2014 Dec 10. PMID:25497013 doi:http://dx.doi.org/10.1016/j.febslet.2014.12.005