+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Interaction of benzoquinones with q negative a and q negative b in oxygen evolving photosystem ii particles from the thermophilic cyanobacterium synechococcus elongatus

Interaction of benzoquinones with q negative a and q negative b in oxygen evolving photosystem ii particles from the thermophilic cyanobacterium synechococcus elongatus

Plant and Cell Physiology 31(7): 1039-1048

The interactions of benzoquinones with the reduced forms of the bound plastoquinone acceptors, QA and QB, were studied with oxygen-evolving photosystem II (PS II) particles from the thermophilic cyanobacterium Synechococcus elongatus, which largely lack pool plastoquinone molecules [Takahashi and Katoh (1986) Biochim, Biophys. Acta 845: 183]. Oxygen evolution in the presence of various electron acceptors was determined and flash-induced changes in absorbance in the blue region were analyzed in terms of difference spectra, dependence on the concentration of benzoquinone and on temperature, and sensitivity to 3-(3,4-dichlorophenyl)-1,1-dimethyl-urea (DCMU). The more hydrophobic the quinone molecule, the higher was the rate of oxygen evolution, and the maximum rate of 3,000 .mu.moles O2 .cntdot. (mg chlorophyll)-1 .cntdot. h-1 was recorded in the presence of phenyl- and dichloro-p-benzoquinones. DCMU inhibited oxygen evolution by more than 95%. However, spectrophotometric studies revealed that, even though electrons were transferred to benzoquinones predominantly via QB2-, the direct oxidation of QA- by added benzoquinones occurred in such a way as to indicate that about 40% of PS II reaction centers were not associated with functional QB sites. QB- was very stable in the presence of ferricyanide. However, benzoquinones induced the slow oxidation of QB-. The characteristics of the benzoquinone reduction in the PS II preparation is discussed.

Please choose payment method:

(PDF emailed within 1 workday: $29.90)

Accession: 007472442

Download citation: RISBibTeXText

Related references

Interaction of bcl-2 with Paxillin through Its BH4 Domain Is Important during Ureteric Bud Branching. The Journal of Biological Chemistry 279(12): 368-74, 2004

Preparation and characterization of functional domains of porcine plasma fibronectin. Natural Science Report of the Ochanomizu University 41(2): 41-56, 1990

Binding affinities of mometasone furoate and related compounds including its metabolites for the glucocorticoid receptor of rat skin tissue. Journal Of Steroid Biochemistry and Molecular Biology. 44(2): 141-145, 1993

The N-Terminal Propeptide and the C Terminus of the Precursor to 20-kilo-dalton Potato Tuber Protein Can Function as Different Types of Vacuolar Sorting Signals. Plant and Cell Physiology 40(11): 1152-1159, 1999

Highly purified recombinant adeno-associated virus vectors. Preparation and quantitation. Methods in Molecular Medicine 69: 427-443, 2002

Refined purification and characterization of z protein. Journal of Biochemistry (Tokyo) 106(1): 110-114, 1989

Preparation and Biological Evaluation of Ethylcellulose Microspheres Containing Tolmetin. Drug Development and Industrial Pharmacy 18(9): 939-959, 1992

EPR study of the electronic properties and weak exchange interactions in bis(L-phenylalaninamidato)Cu(II). Journal of Inorganic Biochemistry 84(3-4): 201-206, 2001

Extraction and characterization of immunoglobulin g fc receptors from group c and group g streptococci. Molecular Immunology 23(4): 425-432, 1986

Photorecording exophthalmometer. Ophthalmology 85(11): 1186-1189, 1978

Size shape and elemental associations in an urban aerosol. Science of The Total Environment 23(none): 393-402, 1982

Characteristics of electron beams from a new 25 mev volt linear accelerator. Medical Physics 12(6): 799-805, 1985

Binding affinities of gallotannin analogs with bovine serum albumin: ramifications for polyphenol-protein molecular recognition. Phytochemistry 51(7): 867-872, 1999

Inhibition by ethanol, acetaldehyde and trifluoroethanol of reactions catalysed by yeast and horse liver alcohol dehydrogenases. Biochemical Journal 171(3): 613-627, 1978

Inhibition by early treatment with bromocriptine of spontaneous mammary tumor development in rats with no side effects. Acta Endocrinologica 101(1): 51-55, 1982