The effect of Cd2+ on the biosynthesis of chlorophyll in leaves of barley |
| |
| Authors: | Allan K Stobart W Trevor Griffiths Ibraheem Ameen-Bukhari Robert P Sherwood |
| |
| Institution: | Dept of Biochemistry. Univ. of Bristol, Bristol RS8 1UG, England;Dept of Botany, The University, Bristol RS8 1UG, England. |
| |
| Abstract: | The effect of cadmium on the biosynthesis of chlorophyll has been investigated in the leaves of dark-grown seedlings of barley ( Hordeum vulture L. cv. Proctor). Cd2+ inhibited the production of chlorophyll by affecting 1) the synthesis of 5-aminolacvulinic acid and 2) the protoehlorophyllide reductase ternary complex with its substrates. Cd2+ had no effect on the constituent enzymes that catalyse the synthesis of free protoehlorophyllide from 5-aminolaevulinic acid. The results obtained are consistent with Cd2+ inhibiting the formation of chlorophyll by reacting with essential thiol groups in both the protochlorophyllide reductase protein and the enzyme(s) involved in the light dependent synthesis of 5-aminolaevulinic acid. |
| |
| Keywords: | 5-aminolaevulinic acid etioplasts Hordeum vulgare protoehlorophyllide protoehlorophyllide reductase |
|
