Crystallization and preliminary X-ray characterization of the tetrapyrrole-biosynthetic enzyme porphobilinogen deaminase from Bacillus megaterium
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چکیده
The enzyme porphobilinogen deaminase (PBGD; hydroxymethylbilane synthase; EC 2.5.1.61) catalyses an early step of the tetrapyrrole-biosynthesis pathway in which four molecules of the monopyrrole porphobilinogen are condensed to form a linear tetrapyrrole. The enzyme possesses a dipyrromethane cofactor which is covalently linked by a thioether bridge to an invariant cysteine residue. Expression in Escherichia coli of a His-tagged form of Bacillus megaterium PBGD permitted the crystallization and preliminary X-ray analysis of the enzyme from this species at high resolution.
منابع مشابه
Structural evidence for the partially oxidized dipyrromethene and dipyrromethanone forms of the cofactor of porphobilinogen deaminase: structures of the Bacillus megaterium enzyme at near-atomic resolution
The enzyme porphobilinogen deaminase (PBGD; hydroxymethylbilane synthase; EC 2.5.1.61) catalyses an early step of the tetrapyrrole-biosynthesis pathway in which four molecules of the monopyrrole porphobilinogen are condensed to form a linear tetrapyrrole. The enzyme possesses a dipyrromethane cofactor, which is covalently linked by a thioether bridge to an invariant cysteine residue (Cys241 in ...
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The enzyme porphobilinogen deaminase (PBGD) is one of the key enzymes in tetrapyrrole biosynthesis. It catalyses the formation of a linear tetrapyrrole from four molecules of the substrate porphobilinogen (PBG). It has a dipyrromethane cofactor (DPM) in the active site which is covalently linked to a conserved cysteine residue through a thioether bridge. The substrate molecules are linked to th...
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