SUMMARY: Techniques were developed for the rapid and simple electron microscopic visualization of isolated cyanophycin granules to allow analysis of their size from cells grown under different conditions. Granules were purified by differential and renografin density-gradient centrifugation from cells grown for various times in chloramphenicol-containing media, or in nitrogen-limited media to which nitrogen was then added back, or under light limitation. Granules were then observed by electron microscopy after staining with uranyl acetate, and random granule diameters were measured. Granule size increased significantly with time following chloramphenicol treatment and following light limitation. This suggests that much of the increase in amount of cyanophycin in cells treated with chloramphenicol or light limitation is caused by increase in granule size rather than in granule number. Insignificant changes in granule size were observed during nitrogen repletion, suggesting increase in granule number, not size.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error