Abstract
Photosystem (PS) II activity of a sulfoquinovosyl diacylglycerol (SQDG)-deficient mutant (hf-2) of Chlamydomonas was partially decreased compared with that of wild-type. The susceptibility to 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) was also modified in the mutant. Photometric measurements in the isolated thylakoid membranes of hf-2 revealed that the lowered activity in the mutant was derived from a decrease in the efficiency of the electron donation from water to tyrosine Z, not from the efficiency of the electron transport from QA to QB. This result was confirmed by the decay kinetics of chlorophyll fluorescence determined in vivo. We conclude that SQDG contributes to maintaining the conformation of PSII complexes, particularly that of D1 polypeptides, which are necessary for maximum activities in Chlamydomonas.
Original language | English |
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Pages (from-to) | 109-112 |
Number of pages | 4 |
Journal | FEBS Letters |
Volume | 553 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - 2003 Oct 9 |
Externally published | Yes |
Keywords
- Chlamydomonas
- Glycolipid
- Photosystem II
- Sulfoquinovosyl diacylglycerol
- Thylakoid membrane
ASJC Scopus subject areas
- Biophysics
- Structural Biology
- Biochemistry
- Molecular Biology
- Genetics
- Cell Biology