Metal Requirement of 5-aminolevulinic Acid dehydratase in Crude Enzyme Solution Prepared from Several Species of Blue-Green Algae

Algae > Volume 14(4); 1999 > Article

Algae 1999;14(4): 223-228.

Sung-Jin Kim, Soon-Ae Yoo, In-cheol Lee

Department of Biology, Paichai University, Department of Biology, Taejon University

ABSTRACT

Changes of 5-aminolevulinic acid dehydratase(ALAD, E.C.4.2.1.24) activity were monitored by the demetallization in the crude enzyme solution prepared from 7 species of blue green algae. The ALAD activities from the 6 species, Synechocystis, Anabaena, Chlorogloea, Oscillatoria, Lyngbya, and Rivularia were higher to a certain extent in the presence with 6 mM MgCl sub(2) than those with same concentration of ZnCl sub(2). ALAD activity in Microcoleus, however, showed little difference with respect to two metal ions under the same assay conditions. By the treatment of Chelex cationic resin ALAD activities in Synechocystis, Anabaena, and Rivularia decreased distinctively. The inhibition in these species was recovered by Chelex treatment. When enzyme solutions were dialyzed against buffer containing EDTA, the profound inhibition of ALAD activity was found in all species. Addition of ZnCl sub(2) into previously dialyzed sample led to the partial recovery of enzyme activity solely in Microcoleus. These results showed indirect evidences that Synechocystis, Anabaena and Rivularia have the Mg-dependent ALAD predominently, but ALAD predomnently, but ALAD in Microcoleus was different in metal binding properties from other blue green blue species. Microcoleus was also from found to have the lowest ratio of chlorophyll/ total phycobilins.

Key words: blue-green algae, 5-aminolevulinic acid dehydratase, metal requirement