Abstract
Lipids are important components of transmembrane protein complexes. In order to study the roles of lipids in photosystem II (PSII), we treated the PSII core dimer complex from a thermophilic cyanobacterium Thermosynechococcus vulcanus with phospholipase A2 (PLA2) and lipase, and examined their effects on PSII structure and function. PLA2-treatment decreased the content of phospholipid, phosphatidylglycerol (PG) by 59%, leading to a decrease of oxygen evolution by 40%. On the other hand, although treatment with lipase specifically decreased the content of monogalactosyldiacylglycerol (MGDG) by 52%, it decreased oxygen evolution only by 16%. This indicates that PG plays a more important role in PSII than MGDG. Both PLA2- and lipase-treatments induced neither the dissociation of PSII dimer, nor any loss of polypeptides. The degradation of PG resulted in a damage to the QB-binding site as demonstrated from photoreduction activity of 2,6-dichlorophenolindophenol and chlorophyll fluorescence yields in the absence or presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea, and the dependencies of oxygen evolution on various electron acceptors before and after PLA2- or lipase-treatments. However, there were approximately three and five molecules of PG and MGDG per PSII reaction center left in the PSII dimeric complex after the PLA2- and lipase-treatments. These lipids are therefore bound to the interior of the protein matrix and resistant to the lipase treatments. The resistance of these lipids against PLA2- and lipase-treatments may be a specific feature of PSII from the thermophilic cyanobacterium, suggesting a possible correlation between binding of lipids and thermostability of PSII.
| Original language | English |
|---|---|
| Pages (from-to) | 469-478 |
| Number of pages | 10 |
| Journal | Photosynthesis Research |
| Volume | 98 |
| Issue number | 1-3 |
| DOIs | |
| Publication status | Published - Oct 2008 |
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Keywords
- Cyanobacteria
- Lipids
- Oxygen evolution
- Phospholipase- treatment
- Phospholipid
- Photosystem II
ASJC Scopus subject areas
- Plant Science
- Cell Biology
- Biochemistry
Cite this
Effects of phospholipase and lipase treatments on photosystem II core dimer from a thermophilic cyanobacterium. / Leng, Jing; Sakurai, Isamu; Wada, Hajime; Shen, Jian-Ren.
In: Photosynthesis Research, Vol. 98, No. 1-3, 10.2008, p. 469-478.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effects of phospholipase and lipase treatments on photosystem II core dimer from a thermophilic cyanobacterium
AU - Leng, Jing
AU - Sakurai, Isamu
AU - Wada, Hajime
AU - Shen, Jian-Ren
PY - 2008/10
Y1 - 2008/10
N2 - Lipids are important components of transmembrane protein complexes. In order to study the roles of lipids in photosystem II (PSII), we treated the PSII core dimer complex from a thermophilic cyanobacterium Thermosynechococcus vulcanus with phospholipase A2 (PLA2) and lipase, and examined their effects on PSII structure and function. PLA2-treatment decreased the content of phospholipid, phosphatidylglycerol (PG) by 59%, leading to a decrease of oxygen evolution by 40%. On the other hand, although treatment with lipase specifically decreased the content of monogalactosyldiacylglycerol (MGDG) by 52%, it decreased oxygen evolution only by 16%. This indicates that PG plays a more important role in PSII than MGDG. Both PLA2- and lipase-treatments induced neither the dissociation of PSII dimer, nor any loss of polypeptides. The degradation of PG resulted in a damage to the QB-binding site as demonstrated from photoreduction activity of 2,6-dichlorophenolindophenol and chlorophyll fluorescence yields in the absence or presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea, and the dependencies of oxygen evolution on various electron acceptors before and after PLA2- or lipase-treatments. However, there were approximately three and five molecules of PG and MGDG per PSII reaction center left in the PSII dimeric complex after the PLA2- and lipase-treatments. These lipids are therefore bound to the interior of the protein matrix and resistant to the lipase treatments. The resistance of these lipids against PLA2- and lipase-treatments may be a specific feature of PSII from the thermophilic cyanobacterium, suggesting a possible correlation between binding of lipids and thermostability of PSII.
AB - Lipids are important components of transmembrane protein complexes. In order to study the roles of lipids in photosystem II (PSII), we treated the PSII core dimer complex from a thermophilic cyanobacterium Thermosynechococcus vulcanus with phospholipase A2 (PLA2) and lipase, and examined their effects on PSII structure and function. PLA2-treatment decreased the content of phospholipid, phosphatidylglycerol (PG) by 59%, leading to a decrease of oxygen evolution by 40%. On the other hand, although treatment with lipase specifically decreased the content of monogalactosyldiacylglycerol (MGDG) by 52%, it decreased oxygen evolution only by 16%. This indicates that PG plays a more important role in PSII than MGDG. Both PLA2- and lipase-treatments induced neither the dissociation of PSII dimer, nor any loss of polypeptides. The degradation of PG resulted in a damage to the QB-binding site as demonstrated from photoreduction activity of 2,6-dichlorophenolindophenol and chlorophyll fluorescence yields in the absence or presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea, and the dependencies of oxygen evolution on various electron acceptors before and after PLA2- or lipase-treatments. However, there were approximately three and five molecules of PG and MGDG per PSII reaction center left in the PSII dimeric complex after the PLA2- and lipase-treatments. These lipids are therefore bound to the interior of the protein matrix and resistant to the lipase treatments. The resistance of these lipids against PLA2- and lipase-treatments may be a specific feature of PSII from the thermophilic cyanobacterium, suggesting a possible correlation between binding of lipids and thermostability of PSII.
KW - Cyanobacteria
KW - Lipids
KW - Oxygen evolution
KW - Phospholipase- treatment
KW - Phospholipid
KW - Photosystem II
UR - http://www.scopus.com/inward/record.url?scp=57849127574&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=57849127574&partnerID=8YFLogxK
U2 - 10.1007/s11120-008-9335-9
DO - 10.1007/s11120-008-9335-9
M3 - Article
C2 - 18668340
AN - SCOPUS:57849127574
VL - 98
SP - 469
EP - 478
JO - Photosynthesis Research
JF - Photosynthesis Research
SN - 0166-8595
IS - 1-3
ER -