Proc Natl Acad Sci U S A
October 1995
Electron microscopy of the cells of the thermogenic appendix of Sauromatum guttatum has revealed a fusion event between pocket-like structures of the rough endoplasmic reticulum (rER) and the plasma membrane. As a result of the fusion event, many regions of the plasma membrane have paired unit membranes (four leaflets instead of two). The fusion allows the transfer of osmiophilic material from the rER pockets to the plasma membrane, where the osmiophilic material is confined to bilayer, pocket-like structures.
View Article and Find Full Text PDFThe fatty acid profiles of various organs of the thermogenic inflorescence of Sauromatum guttatum and of the sporophylls of thermogenic male cones of two cycad species (Encephalartos ferox and Dioon edule var edule and var angustifolium) were determined by gas chromatography. During anthesis, palmitate (16:0), oleate [18:1 (9)], cis-vaccinate [18:1 (11)], and linoleate [18:2 (9, 12)] were the most abundant fatty acids in the Sauromatum appendix. cis-Vaccinic acid, a positional isomer of oleic acid, was identified by comparing its retention time on a gas chromatography column and its mass spectrum to an authentic compound.
View Article and Find Full Text PDFThe pattern of surface temperatures of the inflorescence of Sauromatum guttatum was investigated by using an infrared camera. The male flowers are weakly thermogenic on the first day of inflorescence opening (D-day) as well as on the next day (D + 1), reaching 0.5 to 1 degrees C above ambient temperature.
View Article and Find Full Text PDFThe infrared radiation emitted from the surface of inflorescences of 12 aroid species was monitored with an infrared camera, capable of 0.1°C resolution, and the data were converted to temperature values by means of temperature reference standards. Images representing surface temperatures were obtained forAmorphophallus bulbifer Blume,A.
View Article and Find Full Text PDFIn appendices of Sauromatum guttatum that are developing thermogenicity, mitochondria isolated from successive developmental stages of the inflorescence show an increase in the oxidation rates of proline and glutamate. A similar rise in the oxidation rates of these compounds is observed in mitochondria obtained from the spathe, a nonthermogenic organ of the inflorescence. Changes in oxidative metabolism were also observed in mitochondria isolated from sections of immature appendix treated with salicylic acid (SA) at 0.
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