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dc.contributor.authorBrimble, K. Scott.en_US
dc.date.accessioned2009-10-02T13:19:55Z
dc.date.available2009-10-02T13:19:55Z
dc.date.issued1989-10-02T13:19:55Z
dc.identifier.urihttp://hdl.handle.net/10464/2744
dc.description.abstractABSTRACT Photosynthetic state transitions were investigated in the cyanobacterium Synechococcus sp. PCC 7002 in both wild-type cells and mutant cells lacking phycobilisomes. Preillumination in the presence of DCMU (3(3,4 dichlorophenyl) 1,1 dimethyl urea) induced state 1 and dark adaptation induced state 2 in both wild-type and mutant cells as determined by 77K fluorescence emission spectroscopy. Light-induced transitions were observed in the wildtype after preferential excitation of phycocyanin (state 2) or preferential excitation of chlorophyll .a. (state 1). The state 1 and 2 transitions in the wild-type had half-times of approximately 10 seconds. Cytochrome f and P-700 oxidation kinetics could not be correlated with any current state transition model as cells in state 1 showed faster oxidation kinetics regardless of excitation wavelength. Light-induced transitions were also observed in the phycobilisomeless mutant after preferential excitation of short wavelength chlorophyll !l. (state 2) or carotenoids and long wavelength chlorophyll it (state 1). One-dimensional electrophoresis revealed no significant differences in phosphorylation patterns of resolved proteins between wild-type cells in state 1 and state 2. It is concluded that the mechanism of the light state transition in cyanobacteria does not require the presence of the phycobilisome. The results contradict proposed models for the state transition which require an active role for the phycobilisome.en_US
dc.language.isoengen_US
dc.publisherBrock Universityen_US
dc.subjectCyanobacteria.en_US
dc.subjectSynechococcus.en_US
dc.subjectPhotosynthesis.en_US
dc.subjectPhycobilins.en_US
dc.titleCharacterization of the state transition in the cyanobacterium synechococcus sp. 7002 and a phycobilisome-less Mutanten_US
dc.typeElectronic Thesis or Dissertationen_US
dc.degree.nameM.Sc. Biological Sciencesen_US
dc.degree.levelMastersen_US
dc.contributor.departmentDepartment of Biological Sciencesen_US
dc.degree.disciplineFaculty of Mathematics and Scienceen_US


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