ISSN:
1615-6102
Keywords:
Chlorella fusca g-2
;
Freeze-fracture electron microscopy
;
Thylakoid biogenesis
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary The development of thylakoid protein complexes during light induced greening of a mutant ofChlorella fusca was studied. Separation of chlorophyll-protein complexes and thylakoid polypeptides by LDS-polyacrylamide gel electrophoresis show that cells grown in the dark contain proteins belonging to coupling factor and cytochrome f/b6 complex. Parts of both reaction centers are present also. The antennae complexes are specifically lost in yellow cells. The changes in polypeptide pattern at different stages of development in the light are related to ultrastructural changes. The beginning of membrane appression can be correlated with the appearance of the light-harvesting complex II. While the average diameter of EF-particles increases throughout the greening process, their densitiesapart from the rearrangement due to membrane stacking-remain fairly constant. The kinetics of EFu-particle enlargement are different from those of EFs-particles. PF-faces in thylakoids grown in the dark contain particles of uniform diameter but some of them protrude more from the fracture plane than do their neighbors. During the first hours of greening, their density increases and two classes develop. From the beginning of membrane stacking, the composition of PFu-faces remains constant and PFs-particles increase in number for some time. Results are discussed on the basis of present knowledge of structurefunction relations in thylakoids.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01417534