Summary: The effect of photon fluence rate on grown in Mg- and non-Mg-limited continuous cultures was studied. A decline in photon fluence rate from 445 to 30 μE m s resulted in a decrease of the mean cell volume from 2 to 0.8 μm in the Mg-limited culture. Compared with non-Mg-limited cultures, this was the only obvious difference found when decreasing the photon fluence rate. Altering the photon fluence rate for a Mg-limited chemostat therefore seems to be a suitable system for studies of the Mg-controlled events in cell division of At constant dilution rate, the DNA content per unit cell volume was independent of photon fluence rate, while the RNA content decreased with this factor. The RNA/protein ratio decreased by a factor of 3 in both Mg- and non-Mg-limited cultures, when decreasing the photon fluence rate from 445 to 100 μE m s. The RNA efficiency therefore varied with photon fluence rate and the organism seemed to have surplus RNA at high light intensities.


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