Ultrastructural demonstration of ferricyanide reductase (Diaphorase) activity in the envelopes of the plastids of etiolated barley (Hordeum vulgare L.) leaves |
| |
Authors: | M Ekés |
| |
Institution: | (1) Department of Plant Anatomy, Eötvös Loránd University, Muzeum krt. 4/A, H-1088 Budapest, Hungary |
| |
Abstract: | Electron-dense precipitate was found consistently in the plastid envelope compartment in etiolated barley (Hordeum vulgare L.) leaves, incubated prior to fixation with succinate or malate as substrates and ferricyanide as the electron acceptor. Sulfhydryl reagents p-chloromercuribenzoate and N-ethylmaleimide abolished this reaction, while KCN did not affect it. Prefixation with 0.1% glutaraldehyde followed by incubation in basic media did not change the fine structural localization of precipitate, whereas pretreatment with 1.25% glutaraldehyde resulted in aspecific precipitation. Omission of the subtrate from the medium brought about diminished or negative reaction. Our results indicate that a (possibly not yet assembled) nitrate reductase complex is present in the plastid envelope compartment, the diaphorase part of which is responsible for the observed precipitation.Abbreviations PCMB
p-chloromercuribenzoate
- NEM
N-ethylmaleimide
- NR
nitrate reductase
- SDH
succinic dehydrogenase |
| |
Keywords: | Diaphorase (nitrate reductase) Hordeum Leaf (etiolated) Nitrate reductase Plastid envelope |
本文献已被 SpringerLink 等数据库收录! |
|