SPECTRAL CHARACTERIZATION OF LIGHT-REDUCIBLE CYTOCHROME IN A PLASMA MEMBRANE-ENRICHED FRACTION AND IN OTHER MEMBRANES FROM CAULIFLOWER INFLORESCENCES |
| |
| Authors: | S Widell R J Caubergs † C Larsson † |
| |
| Institution: | *Department of Plant Physiology, University of Lund, P.O.B. 7007, S-22007 Lund, Sweden;†R.U.C.A. Groenenborgerlaan 171, 2020 Antwerpen, Belgium;†Department of Biochemistry. University of Lund, P.O.B. 740, S-22007 Lund, Sweden |
| |
| Abstract: | Abstract— Low temperature spectroscopy has been used to characterize microsomal fractions obtained from cauliflower inflorescences ( Brasska oleracea L.) by differential centrifugation and partition in an aqueous polymer two-phase system. The plasma membrane-enriched fraction (U3) was found to contain one dominant b -cytochrome, which could be reduced both by blue light and by dithionite. An action spectrum of the blue light-induced absorbance change LIAC, Δ(A430—A410)] associated with the reversible reduction of this b -type cytochrome indicated that the primary light-receptor was a flavin-like compound. Another microsomal fraction (L3) containing membranes from mitochondria, endoplasmic reticulum and other organelles also contained light-reducible cytochrome. One of these could be identified as cytochrome c oxidase, and another may be identical to cytochrome b 5 of the endoplasmic reticulum. |
| |
| Keywords: | |
|
|
