Effects of glycerol and high temperatures on structure and function of phycobilisomes in Synechocystis sp. PCC 6803.
The effects of glycerol and high temperatures on structure and function of phycobilisomes (PBSs) in vivo were investigated in a chlL deletion mutant of the cyanobacterium Synechocystis sp. PCC 6803. When the mutant was grown under light-activated heterotrophic growth conditions, it contained intact and functional PBSs, but essentially no chlorophyll and photosystems. So the structural and functional changes of the mutant PBSs in vivo can be handily detected by measurement of low temperature (77 K) fluorescence emission spectra. High concentration glycerol induced an obvious disassembly of PBSs and the dissociation of phycocyanins in the rod substructures into their oligomers and monomers. PBSs also disassembled at high temperatures and allophycocyanins were more sensitive to heat stress than phycocyanins. Our results demonstrate that the chlL(-) mutant strain is an advantageous model for studying the mechanisms of assembly and disassembly of protein complexes in vivo.
Mao
Hai-Bin
HB
State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, PR China.
Li
Guo-Fu
GF
Li
Dong-Hai
DH
Wu
Qing-Yu
QY
Gong
Yan-Dao
YD
Zhang
Xiu-Fang
XF
Zhao
Nan-Ming
NM
D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000458:Cyanobacteria / Q000737:chemistry / Q000187:drug effects* / Q000235:genetics; D005990:Glycerol / Q000494:pharmacology*; D006358:Hot Temperature; D045342:Light-Harvesting Protein Complexes; D009154:Mutation / Q000235:genetics; D045524:Phycobilisomes; D011506:Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship
D001426:Bacterial Proteins; D045342:Light-Harvesting Protein Complexes; D045524:Phycobilisomes; D011506:Proteins; C095441:chlL protein, bacteria; D005990:Glycerol