Ferredoxin Isolated from Plant Non-Photosynthetic Tissues. Purficaition and Characterization

摘要

A ferredoxin was isolated from non-photosynthetic tissues of the lower storage root of radish (Raphanus sativusL. var.acantiformiscultivarMiyashige) in a pure form by conventional means. It showed the characteristic features in its absorption spectrum of chloroplast-type ferredoxin. However, amino acid composition and amino (N)- terminal sequence were different from those of radish leaf ferredoxin. Root ferredoxin was able to transfer electrons from dithionite to nitrite reductase EC 1.7.7.1 isolated from mung bean seedling roots and also to mediate NADP+photoreduction in spinach broken chloroplasts.It therefore is suggested that a set of distinctive molecular species of ferredoxin is present in non-photosynthetic tissues and functions as a redox mediator in ferredox-independent enzyme systems.