ISSN:
1399-3054
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
Iron-deficient bean plants (Phaseolus vulgaris L. cv. Prélude) exhibited a ferric reducing activity in the roots, with kinetics characteristic for matrix-bound enzymes: the reaction rate was proportional to substrate (Fe-EDTA) concentration until 100 μM, and at higher concentrations it leveled off to a maximum; the Lineweaver-Burk plot yielded a non-linear relationship between rate −1 and substrate −1. The Arrhenius plot yielded apparent activation energies which were dependent on substrate concentration. No evidence was obtained for the secretion by roots of a low molecular weight metabolite involved in the reduction of iron prior to its uptake. The results are interpreted to indicate that the ferric reducing activity in the roots of iron-deficient bean plants is located in an enzyme in the plasmalemma of the cortex or epidermis cells.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1399-3054.1983.tb00757.x
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