title: Effects of glycerol and high temperatures on structure and function of phycobilisomes in Synechocystis sp. PCC 6803.
abstract: 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.
authors.affiliation: State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, PR China.
authors.forename: Hai-Bin
authors.initials: HB
authors.lastname: Mao
authors.forename: Guo-Fu
authors.initials: GF
authors.lastname: Li
authors.forename: Dong-Hai
authors.initials: DH
authors.lastname: Li
authors.forename: Qing-Yu
authors.initials: QY
authors.lastname: Wu
authors.forename: Yan-Dao
authors.initials: YD
authors.lastname: Gong
authors.forename: Xiu-Fang
authors.initials: XF
authors.lastname: Zhang
authors.forename: Nan-Ming
authors.initials: NM
authors.lastname: Zhao
mesh_terms: 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
chemical_list: D001426:Bacterial Proteins; D045342:Light-Harvesting Protein Complexes; D045524:Phycobilisomes; D011506:Proteins; C095441:chlL protein, bacteria; D005990:Glycerol