| Abstrakt: |
NADPH-protochlorophyllide oxidoreductase (PChlide reductase, EC 1.3.1.33), a key enzyme in light-dependent greening and the conversion of etioplasts into chloroplasts was investigated in the the greening mutant C-2A' of the unicellular green alga Scenedesmus obliquus. In the absence of detergent, the solublization of the enzyme increased with high glycerol concentrations in the buffer. Solubilization capacities of 4 non-ionic or zwitterionic detergents. Triton X- 100, CHAPS, octylglucoside and decyl-maltopyranoside, were compared. Due to the addition of these detergents, the enzyme activity in the soluble fraction was increased several fold. Hydrophobicity of the enzyme was analyzed by Triton X-114 phase partitioning. The protein had a preference for the aqueous phase, but its distribution was strongly influenced by the glycerol concentration of the buffer. These results indicate that the PChlide reductase of the green alga Scenedesmus obliquus is a hydrophobic, membrane-associated enzyme, but not an integral membrane protein. [ABSTRACT FROM AUTHOR] |
Plný text