Halogenated 1,4-benzoquinones as irreversibly binding inhibitors of photosynthetic electron transport

Oettmeier, Walter; Masson, Klaus; Dostatni, Ralf

doi:10.1016/0005-2728(87)90027-2

Cited by 28 publications

(8 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is of note that the detailed geometry of DBMIB and in particular the position of the bromide atoms with respect to the Rieske cluster is only one of a set of different possibilities. We expect that an examination of the range of DBMIB‐derivatives described previously [21] with respect to the phenomena reported in this work will provide a more detailed picture of the interaction between quinones and quinone analogs in the Q o ‐site and the Rieske cluster.…”

Section: Resultsmentioning

confidence: 77%

“…Halogenated quinone analogs and in particular the dibromo‐derivative DBMIB [19–21] have been described as potent inhibitors of the chloroplast cytochrome b 6 f complex [22–26] and with much lesser efficiency of cytochrome bc 1 complexes from mitochondria [27] and purple bacteria [28]. DBMIB was shown to bind at the Q o ‐site of the enzyme and to strongly alter the EPR spectrum of the Rieske cluster (in particular, inducing a shift of the g y ‐line from 1.89 to 1.94) [24].…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

The Q_o‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton

et al. 1999

View full text Add to dashboard Cite

The interaction of the inhibitor 2,5-dibromo-3-methyl-6-isopropylbenzoquinone (DBMIB) with the Rieske protein of the chloroplast b 6 f complex has been studied by EPR. All three redox states of DBMIB were found to interact with the iron-sulphur cluster. The presence of the oxidised form of DBMIB altered the equilibrium distribution of the Rieske protein's conformational substates, strongly favouring the proximal position close to heme b L . In addition to this conformational effect, DBMIB shifted the pK-value of the redox-linked proton involved in the iron-sulphur cluster's redox transition by about 1.5 pH units towards more acidic values. The implications of these results with respect to the interaction of the native quinone substrate and the Rieske cluster in cytochrome bc complexes are discussed.z 1999 Federation of European Biochemical Societies.

show abstract

Section: Resultsmentioning

confidence: 77%

Section: Resultsmentioning

confidence: 99%

The Q_o‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton

et al. 1999

View full text Add to dashboard Cite

show abstract

“…Tetrabromoand phenyl-BQs are very hydrophobic so that they presumably cannot approach the Mn3+ which would be located in hydrophilic environment. We note that tetrabromo-BQ has been reported to covalently bind to thylakoid proteins (Oettmeier et al, 1987).…”

Section: Discussionmentioning

confidence: 78%

Improvement by benzoquinones of the quantum yield of photoactivation of photosynthetic oxygen evolution: direct evidence for the two-quantum mechanism

Miyao-Tokutomi¹,

Inoue²

1992

Biochemistry

View full text Add to dashboard Cite

Effects of eight differently substituted 1,4-benzoquinones (BQs) on the quantum yield of photoactivation of oxygen evolution (reconstitution of the Mn cluster) were examined with wheat photosystem II (PSII) membranes depleted of the Mn cluster by treatment with 1.0 mM NH2OH. Illumination with 10 flashes at 0.25-s intervals of the PSII membranes in the presence of 2.0 mM Mn2+, 20 mM Ca2+, and 1.2 M Cl- restored 14% of oxygen-evolving activity destroyed by the NH2OH treatment. Among the benzoquinones tested, DBMIB (2,5-dibromo-3-methyl-6-isopropyl-BQ) and tetramethyl-BQ did not enhance the activity recovery, but all the others doubled the recovery when present at their optimal concentrations during illumination. The order of effectiveness was tetrabromo-, phenyl-, and 2,6-dichloro-BQs greater than or equal to 2,5-dichloro-BQ greater than tetrachloro-BQ greater than 2,5-dimethyl-BQ, though the differences were small. This order reflects their efficiencies as electron acceptors of PSII. This finding, together with others, suggests that the enhancement of activity recovery results from rapid oxidation by the benzoquinones of the reduced form of the quinone acceptors in PSII, QA- and QB-, which cause loss of an oxidized intermediate through charge-recombination reaction with Mn3+. The flash-number dependence of the recovery of oxygen-evolving activity indicated that the activity was not restored after one flash but recovered significantly after illumination with two flashes and then further increased upon additional flashes. This provides direct evidence that the minimum quantum requirement for photoactivation is two.

show abstract

“…In addition to that, another possibility is mechanistically very interest ing. If exogenous quinones are able to bind in the PS II complex [16,17] further redox groups could be incorporated that might effect the reaction sequence of w ater cleavage. Recently, halogenated 1,4-benzoquinones were shown to affect specifically the D CM U sensitivity of the PS II acceptor side [18,19].…”

Section: Introductionmentioning

confidence: 99%

Tribromotoluquinone Induced Modifications of the Oscillation Pattern of Oxygen Evolution and of Herbicide Binding in Thylakoids and PS II Membrane Fragments from Spinach

Ренгер

Messinger

Fromme

1989

Zeitschrift Für Naturforschung C

View full text Add to dashboard Cite

M ax-V olm er-Institut für B iophysikalische und Physikalische C hem ie, T U B erlin. S traße des 17. Ju n i 135. 1000 B erlin 12 Z. N aturforsch. 44c, 423-430 (1989); received Ja n u a ry 2 6/F ebruary 23, 1989 Dedicated to Professor A chim Trebst on the occasion o f his 60th birthday Photosystem II, H a lo g en ated /?-B enzoquinones, O xygen Y ield O scillation, Q u in o n e /H erb icid e In tera ctio n , B inding SitesIn the p re sen t study the effect o f T B T Q on PS II and its m utual interaction with D C M U was analyzed by m easu rem en ts o f th e oxygen yield oscillation p a tte rn and o f D C M U binding. It was found: 1 )T B T Q in its reduced form is able to induce the red u ctio n o f D ox which gives rise to an accelerated decay of S2 and S3 o f the w ateroxidizing com plex. 2 ) T rito n X-100 trea tm e n t used for isolation o f PS II m em b ran e fragm ents does not significantly affect the lateral m obility o f p lasto q u in o n e w ithin the m em b ran e. T B T Q bound to the th y lakoid m em b ran e does not en h an c e the e lectro n pool capacity in PS II m em b ran e fragm ents. [7]) of the PS II reaction center and even the catalytic site of water oxidation (for reviews, see ref. [8 , 9]). Despite the huge pro gress in our understanding of the structural organiza tion of system II during the last years [8 , 9] the possi-

show abstract

Halogenated 1,4-benzoquinones as irreversibly binding inhibitors of photosynthetic electron transport

Cited by 28 publications

References 26 publications

The Q_o‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton

The Q_o‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton

Improvement by benzoquinones of the quantum yield of photoactivation of photosynthetic oxygen evolution: direct evidence for the two-quantum mechanism

Tribromotoluquinone Induced Modifications of the Oscillation Pattern of Oxygen Evolution and of Herbicide Binding in Thylakoids and PS II Membrane Fragments from Spinach

Contact Info

Product

Resources

About

Halogenated 1,4-benzoquinones as irreversibly binding inhibitors of photosynthetic electron transport

Cited by 28 publications

References 26 publications

The Qo‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton

The Qo‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton

Improvement by benzoquinones of the quantum yield of photoactivation of photosynthetic oxygen evolution: direct evidence for the two-quantum mechanism

Tribromotoluquinone Induced Modifications of the Oscillation Pattern of Oxygen Evolution and of Herbicide Binding in Thylakoids and PS II Membrane Fragments from Spinach

Contact Info

Product

Resources

About

The Q_o‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton

The Q_o‐site inhibitor DBMIB favours the proximal position of the chloroplast Rieske protein and induces a pK‐shift of the redox‐linked proton