1i1h
| |||||||
| , resolution 2.60Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Gene: | COBH (Pseudomonas denitrificans) | ||||||
| Activity: | Precorrin-8X methylmutase, with EC number 5.4.1.2 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE ANALYSIS OF PRECORRIN-8X METHYLMUTASE COMPLEX WITH HYDROGENOBYRINIC ACID
OverviewOverview
BACKGROUND: The crystal structure of precorrin-8x methyl mutase (CobH), an enzyme of the aerobic pathway to vitamin B12, provides evidence that the mechanism for methyl migration can plausibly be regarded as an allowed [1,5]-sigmatropic shift of a methyl group from C-11 to C-12 at the C ring of precorrin-8x to afford hydrogenobyrinic acid. RESULTS: The dimeric structure of CobH creates a set of shared active sites that readily discriminate between different tautomers of precorrin-8x and select a discrete tautomer for sigmatropic rearrangement. The active site contains a strictly conserved histidine residue close to the site of methyl migration in ring C of the substrate. CONCLUSION: Analysis of the structure with bound product suggests that the [1,5]-sigmatropic shift proceeds by protonation of the ring C nitrogen, leading to subsequent methyl migration.
About this StructureAbout this Structure
1I1H is a Single protein structure of sequence from Pseudomonas denitrificans. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of precorrin-8x methyl mutase., Shipman LW, Li D, Roessner CA, Scott AI, Sacchettini JC, Structure. 2001 Jul 3;9(7):587-96. PMID:11470433
Page seeded by OCA on Thu Mar 20 11:44:18 2008