[19] Preparation of porphobilinogen

Publisher Summary This chapter illustrates the preparation of porphobilinogen (PBG). PBG is a normal intermediate in the biosynthesis of heme. An enzymatic method has been considered for the preparation of porphobilinogen with good yield using both δ-aminolevulinic acid and the enzyme aminolevulinic acid dehydratase. PBG can be isolated and purified by either of the two procedures of isolation and can be essentially identified by different methods. By paper chromatography, a biosynthetic PBG runs as a single spot having the same R f as that for the markers. A solution of biosynthetic PBG when mixed with an equal volume of Ehrlich's reagent gives maxima at 555 m μ and 525 m μ . PBG can be enzymatically converted into uroporphyrinogens by means of the deaminase–isomerase enzymatic complex.