Delta-Aminolevulinic acid synthase from chick embryo liver mitochondria. I. Purification and some properties.
The purification of hepatic delta-aminolevulinic acid synthase (EC 2.3.1.37) was accomplished from chick embryo liver mitochondria, which had been treated with the combination of drugs, 2-allylisopropylacetamide and 1,4-dihydro-3,5-dicarbethoxycollidine to produce a high starting level of enzyme activity. After extraction from the mitochondria by sonication, the enzyme was purified to a final specific activity of over 10,000 nmol of aminolevulinate formed/30 min/mg of protein/37 degrees, using the techniques of Sephadex chromatography, ammonium sulfate fractionation, affinity chromatography for pyridoxal phosphate, and preparative isoelectric focusing. An isoelectric point of 7.0 and a molecular weight of 87,000 were obtained for the native enzyme. The subunit molecular weight of 49,000, obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, suggested it was a dimer. The enzyme was inhibited by p-chloromercuribenzoate and N-ethylmaleimide, stimulated by cations and exhibited an ultraviolet absorption spectrum characteristic of pyridoxal 5'-phosphate enzymes with absorption maxima at 325 and 420 nm.
D000624:5-Aminolevulinate Synthetase / Q000302:isolation & purification* / Q000378:metabolism; D000818:Animals; D002642:Chick Embryo; D003997:Dicarbethoxydihydrocollidine / Q000494:pharmacology; D004355:Drug Stability; D008970:Molecular Weight; D009994:Osmolar Concentration; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet
D003997:Dicarbethoxydihydrocollidine; D000624:5-Aminolevulinate Synthetase