Molecular Species Composition of Phosphatidylglycerols from Chilling-Sensitive and Chilling-Resistant Plants

The molecular species of phosphatidylglycerols from leaves of 9 species of chilling-sensitive plants and 12 species of chilling-resistant plants were analyzed by gas-liquid chromatography and gas chromatography-mass spectrometry. The sum of the contents of the dipalmitoyl plus the 1-palmitoyl-2-(trans-3-hexadecenoyl) species of phosphatidylglycerol ranged from 3 to 19% of the total of this lipid in the chilling-resistant plants, and from 26 to 65% in the chilling-sensitive plants. These findings suggest that these two molecular species of phosphatidylglycerols are closely associated with the chilling sensitivity of the plants. The biochemical difference between the chilling-sensitive and the chilling-resistant plants is discussed in terms of the activities of enzymes involved in phosphatidylglycerol biosynthesis in the chloroplasts.