Identification of the photosynthetic CO2 fixation inhibitors in isolated pine chloroplasts as resin acids |
| |
Authors: | Björn Martin Gunilla Malmberg Rolf Gref Gunnar Öquist |
| |
Institution: | Dept of Plant Biology, Univ. of Illinois, Urbana, IL 61801, USA;Dept of Plant Physiology, Univ. of Umea, S-901 87 Umeå, Sweden;Dept of Forest Genetics and Plant Physiology, The Swedish Univ. of Agricultural Sciences, S-901 83 Umea, Sweden. |
| |
Abstract: | Thus far all attempts to isolate CO, fixing chloroplasts from pine have failed. In this paper it is proposed that resin acids present in pine needles partition into membranes during chloroplast isolation and interfere with specific reactions of the Calvin cycle. CO, fixation by isolated spinach chloroplasts was strongly inhibited by the introduction of a suspension of chloroplasts isolated from Pinus sylvestris L. A partially purified organic extract obtained from chloroplasts of this pine species also strongly inhibited CO, fixation by the spinach chloroplasts. The major inhibitory compounds from the organic extract were identified as a mixture of resin acids by gas-liquid chromatography and mass spectrometry. Two resin acids, abietic acid and dehydroabietic acid, were tested for inhibitory activity. Both resin acids were potent inhibitors of photosynthetic CO2fixation, with dehydroabietic acid being about three times more potent than abietic acid. |
| |
Keywords: | Calvin cycle Pinus sylvestris |
|
|