1knc
Structure of AhpD from Mycobacterium tuberculosis, a novel enzyme with thioredoxin-like activity.
|
OverviewOverview
Mycobacterium tuberculosis (Mtb) mounts a stubborn defense against oxidative and nitrosative components of the immune response. Dihydrolipoamide dehydrogenase (Lpd) and dihydrolipoamide succinyltransferase (SucB) are components of alpha-ketoacid dehydrogenase complexes that are central to intermediary metabolism. We find that Lpd and SucB support Mtb's antioxidant defense. The peroxiredoxin alkyl hydroperoxide reductase (AhpC) is linked to Lpd and SucB by an adaptor protein, AhpD. The 2.0 angstrom AhpD crystal structure reveals a thioredoxin-like active site that is responsive to lipoamide. We propose that Lpd, SucB (the only lipoyl protein detected in Mtb), AhpD, and AhpC together constitute a nicotinamide adenine dinucleotide (reduced)-dependent peroxidase and peroxynitrite reductase. AhpD thus represents a class of thioredoxin-like molecules that enables an antioxidant defense.
About this StructureAbout this Structure
1KNC is a Single protein structure of sequence from Mycobacterium tuberculosis with as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Metabolic enzymes of mycobacteria linked to antioxidant defense by a thioredoxin-like protein., Bryk R, Lima CD, Erdjument-Bromage H, Tempst P, Nathan C, Science. 2002 Feb 8;295(5557):1073-7. Epub 2002 Jan 17. PMID:11799204
Page seeded by OCA on Thu Feb 21 13:35:56 2008