Thylakoid membranes ultrastructure

Figure 4 shows a typical ultrastructure of hairy root cells observed under an electron microscope. In the case of photomixotrophic hairy roots, a plastid with a chloroplast-like structure was observed in the light-grown root cells, being associated with thylakoid membranes and grana stacks the particles in the vi-... 

Simpson, D.J. 1981. The ultrastructure of barley thylakoid membranes. In Photosysthesis III. Structure and Molecular Organization of the Photo synthetic apparatus. (Ed. G.Akoyunoglou), (Balaban Int. Sci. Services, Philadelphia, Pa.), pp. 15-22. 

Simpson, D.J. and Robinson S.P. 1984. Freeze-fracture ultrastructure of thylakoid membranes in chloroplasts from manganese-deficient plants. Plant Physiol. 74, 735-741. 

It is clear that the ultrastructure of the phycobilisomes of Rhodosorus is markedly different to any previously described. They seem also to have a close relationship with the particle arrangement on both PF and EF faces of the thylakoid membrane. 

On the basis of X-ray diffraction studies, the ultrastructure of chloroplast membrane has been analyzed by Kreutz - s, and the subject reviewed by him. Using the freeze-etching technique, Muehlethaler has suggested a picture for the thylakoid membrane based upon the bimolecular leaflet model. The salient feature in all these proposed models lies in their oriented bilayer lipid core, onto which other important cellular constituents, such as proteins and pigments, may interact through either ionic or van der Waals attraction, or both. Muehlethaler s interpretation is of special interest, in view of the experiments using the pigmented... 

The ultrastructural features, visualized by freeze-fracture electron microscopy, of chloroplasts isolated from leaves of Arabidopsis mutants harvested at the rosette stage [18] have also been compared. A striking feature of the fracture faces of stacked thylakoids in the two mutants is the presence of aligned membrane-associated particles together with regions of randomly distributed particles. 

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