Summary: Dark-grown resting (non-dividing) cells of var. and mutants WBUL (with a proplastid remnant) and WBSmL (lacking plastids) incubated with SO form a series of labelled lipids which are low or absent in dividing cells. These lipids all release labelled taurine on mild acid-hydrolysis. Treatment of the labelled lipids with 2,4-dinitrofluorobenzene (DNFB) followed by acid hydrolysis does not yield labelled dinitrophenyltaurine (DNP-taurine), but treatment with DNFB after hydrolysis readily forms labelled DNP-taurine, indicating that taurine is linked to the lipids by at least the amino group. Illumination increases the labelling of these taurolipids in plastid-containing cells (wild-type and WBUL) but has little effect in cells lacking plastids (WBSmL); labelling is highest in W cells irrespective of illumination. This indicates that the presence of a plastid may exert a negative control on taurolipid formation which is relieved by light. The same series of labelled lipids is found in isolated purified mitochondria from mutant W, indicating that this organelle is a site for taurolipid deposition. The formation of taurolipids under non-dividing conditions may be a response to nutritional stress and these negatively charged constituents (as well as the thylakoid sulpholipid) may serve to protect membranes by repelling deleterious negatively charged oxygen species.


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