Directed mutagenesis as a probe of photosystem II function

Bowlby, N; Sithole, I; McIntosh, L; James, J; Babcock, G

Title: Directed mutagenesis as a probe of photosystem II function

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Abstract

Several mutants of Synechocystis 6803 have been generated by site-directed mutagenesis of psbA and psbD in order to study the roles of the D1 and D2 proteins during H{sub 2}O oxidation. Of key importance to these studies is the analysis of PSII electron transfer components such as Y{sub Z}{sup +} and Y{sub D}{sup +}, and the identification of possible ligands to Mn and Ca. Detailed information can be gained through EPR spectroscopy, however, sensitivity is limited by the PSII concentration of the sample. A simple procedure for the purification of PSII from this cyanobacterium, in sufficient amounts for EPR studies, will be presented. Preliminary results from mutant analysis extend the characterization of the two tyrosine radicals and suggest an important structural role for Pro{sup 162} of D1 and Pro{sup 161} of D2 in the ability of the photosystem to form the radical species on the adjacent tyrosine residues Tyr{sup 161} and Tyr{sup 160} on D1 and D2 respectively.

Authors:

Bowlby, N; Sithole, I; McIntosh, L ^[1]; James, J; Babcock, G ^[2]

MSU-DOE Plant Research Laboratory, East Lansing, MI (USA)
Michigan State Univ., East Lansing (USA)

Publication Date:: Tue May 01 00:00:00 EDT 1990

OSTI Identifier:: 5629081

Report Number(s):: CONF-9007196-
Journal ID: ISSN 0079-2241; CODEN: PPYSA

Resource Type:: Conference

Journal Name:: Plant Physiology, Supplement; (USA)

Additional Journal Information:: Journal Volume: 93:1; Conference: Annual meeting of the American Society of Plant Physiologists, Indianapolis, IN (USA), 29 Jul - 2 Aug 1990; Journal ID: ISSN 0079-2241

Country of Publication:: United States

Language:: English

Subject:: 59 BASIC BIOLOGICAL SCIENCES; CYANOBACTERIA; BIOCHEMICAL REACTION KINETICS; CALCIUM; LIGANDS; MANGANESE; OXIDATION; PHOTOSYNTHESIS; POLYPEPTIDES; SPECTROSCOPY; TYROSINE; ALKALINE EARTH METALS; AMINO ACIDS; CARBOXYLIC ACIDS; CHEMICAL REACTIONS; ELEMENTS; HYDROXY ACIDS; KINETICS; METALS; MICROORGANISMS; ORGANIC ACIDS; ORGANIC COMPOUNDS; PEPTIDES; PHOTOCHEMICAL REACTIONS; PROTEINS; REACTION KINETICS; SYNTHESIS; TRANSITION ELEMENTS; 550200* - Biochemistry

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                    Bowlby, N, Sithole, I, McIntosh, L, James, J, and Babcock, G. Directed mutagenesis as a probe of photosystem II function.  United States: N. p., 1990. 
        Web.

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                    Bowlby, N, Sithole, I, McIntosh, L, James, J, & Babcock, G. Directed mutagenesis as a probe of photosystem II function.  United States.

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                    Bowlby, N, Sithole, I, McIntosh, L, James, J, and Babcock, G. 1990.  
        "Directed mutagenesis as a probe of photosystem II function".  United States.

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@article{osti_5629081,

  title        = {Directed mutagenesis as a probe of photosystem II function},

  author       = {Bowlby, N and Sithole, I and McIntosh, L and James, J and Babcock, G},

  abstractNote = {Several mutants of Synechocystis 6803 have been generated by site-directed mutagenesis of psbA and psbD in order to study the roles of the D1 and D2 proteins during H{sub 2}O oxidation. Of key importance to these studies is the analysis of PSII electron transfer components such as Y{sub Z}{sup +} and Y{sub D}{sup +}, and the identification of possible ligands to Mn and Ca. Detailed information can be gained through EPR spectroscopy, however, sensitivity is limited by the PSII concentration of the sample. A simple procedure for the purification of PSII from this cyanobacterium, in sufficient amounts for EPR studies, will be presented. Preliminary results from mutant analysis extend the characterization of the two tyrosine radicals and suggest an important structural role for Pro{sup 162} of D1 and Pro{sup 161} of D2 in the ability of the photosystem to form the radical species on the adjacent tyrosine residues Tyr{sup 161} and Tyr{sup 160} on D1 and D2 respectively.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/5629081},
  journal      = {Plant Physiology, Supplement; (USA)},

  issn         = {0079-2241},

  number       = ,

  volume       = 93:1,

  place        = {United States},

  year         = {Tue May 01 00:00:00 EDT 1990},

  month        = {Tue May 01 00:00:00 EDT 1990}

}

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