
Apo‐ and Reconstituted Holoenzymes of Metapyrocatechase from Pseudomonas putida
Author(s) -
Takemori Shigeki,
Katagiri Masayuki,
Komiyama Tadazumi
Publication year - 1971
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1971.tb01606.x
Subject(s) - ferrous , chemistry , pseudomonas putida , enzyme , sephadex , reagent , chromatography , biochemistry , pseudomonas , molecular mass , biology , organic chemistry , bacteria , genetics
In order to ascertain the role of metal in the structure and function of the iron‐containing oxygenase, we have successfully obtained stable, crystalline apo‐ and fully reconstituted holoenzymes from metapyrocatechase of Pseudomonas putida . Ultracentrifugally and electrophoretically homogeneous apoenzyme is prepared by dialysis against o ‐phenanthroline followed by chromatography on DEAE‐Sephadex. The apoenzyme is essentially free of iron and inactive. Fully active holoenzyme, which contains 3 g‐atoms of iron per mol of protein, can be reconstituted by incubating the apoenzyme with ferrous ion. Using these preparations, the close correlation between iron content and activity of the enzyme has been demonstrated. The apoenzyme is, in terms of its molecular weight and sensitivity to sulfhydryl group reagents, indistinguishable from the reconstituted holoenzyme, indicating that no gross change of the protein structure has occurred.