Membrane phase transitions and succinate oxidase activity in an extremely thermophilic bacterium

Semiquinone is an intermediary product of the oxidation of daphnetin (7,8-dihydroxycoumarin) and esculetin (6,7-dihydroxycoumarin) by diphenol oxidase; its concentration rapidly decreases. When the oxidation is effected by ferricytochrome c, the concentration of the semiquinone remains practically constant for a long period. Similarly, the ability of the products of daphnetin oxidation by diphenol oxidase to inhibit succinate oxidase activity in mitochondrial fragments rapidly decreases with time; the decrease is considerably slower in the case of cytochrome c. The inhibitory activity of the product decreases with time also during esculetin oxidation by ferricyanide. This indicates that the inhibitory effects must be ascribed predominantly to the semiquinone, the quinone is less efficient. The inhibition of succinate oxidase or succinate dehydrogenase was strongly decreased when the enzyme preparation of Keilin and Hartree was incubated with esculetin and ferricyanide in the presence of KCN or under anaerobic conditions. This demonstrates that the reaction of the inhibitor with the enzyme either involves subsequent oxidations or that the inhibitor preferentially reacts with the oxidized form of the sensitive component of the respiratory chain. The second alternative is very little probable since there is no correlation between the degree of inhibition and the binding of the inhibitor to mitochondrial fragments.

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The effect of liposomes on thermotropic membrane phase transitions of bovine spermatozoa and oocytes: implications for reducing chilling sensitivity

Cryobiology ◽

10.1016/s0011-2240(02)00123-2 ◽

2002 ◽

Vol 45 (2) ◽

pp. 143-152 ◽

Cited By ~ 62

Author(s):

Y Zeron ◽

M Tomczak ◽

J Crowe ◽

A Arav

Keyword(s):

Phase Transitions ◽

Membrane Phase ◽

Chilling Sensitivity ◽

Bovine Spermatozoa

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Stimulation of the alternative oxidase of Neurospora crassa by Nucleoside phosphates

Biochemical Journal ◽

10.1042/bj1880141 ◽

1980 ◽

Vol 188 (1) ◽

pp. 141-144 ◽

Cited By ~ 24

Author(s):

J Vanderleyden ◽

C Peeters ◽

H Verachtert ◽

H Bertrand

Keyword(s):

Neurospora Crassa ◽

Oxidase Activity ◽

Alternative Oxidase ◽

Purine Nucleoside ◽

Submitochondrial Particles ◽

Fold Stimulation ◽

Succinate Oxidase ◽

Stimulation Of

The alternative-oxidase-mediated succinate oxidase activity of Neurospora crassa decreases drastically when mitochondria are fractionated into submitochondrial particles or treated with deoxycholate. The activity, however, can be completely restored in the presence of nucleoside 5′-monophosphates. The purine nucleoside 5′-monophosphates are more effective than the pyrimidine homologues. 5′-GMP gives a 10-fold stimulation of the alternative-oxidase-mediated succinate oxidase activity in submitochondrial particles. A comparison is made with the results obtained earlier with Moniliella tomentosa [Hanssens & Verachtert (1976) J. Bacteriol. 125, 825–835; Vanderleyden, Van Den Eynde & Verachtert (1980) Biochem. J. 186, 309–316].

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Succinate oxidase activity in the absence of ubiquinone

FEBS Letters ◽

10.1016/0014-5793(71)80236-3 ◽

1971 ◽

Vol 13 (5) ◽

pp. 265-266 ◽

Cited By ~ 9

Author(s):

S.P.J. Albracht ◽

H. Van Heerikhuizen ◽

E.C. Slater

Keyword(s):

Oxidase Activity ◽

Succinate Oxidase

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Comment on: X‐ray diffraction study of the effects of pressure on bilayer to nonbilayer lipid membrane phase transitions

The Journal of Chemical Physics ◽

10.1063/1.456139 ◽

1989 ◽

Vol 90 (2) ◽

pp. 1293-1295 ◽

Cited By ~ 8

Author(s):

E. Shyamsunder ◽

P. Botos ◽

S. M. Gruner

Keyword(s):

Phase Transitions ◽

Diffraction Study ◽

Lipid Membrane ◽

Membrane Phase ◽

X Ray Diffraction ◽

X Ray

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Membrane phase transitions and the transport of chlortetracycline

Archives of Biochemistry and Biophysics ◽

10.1016/0003-9861(75)90230-1 ◽

1975 ◽

Vol 168 (1) ◽

pp. 81-88 ◽

Cited By ~ 10

Author(s):

Michael E. Dockter ◽

James A. Magnuson

Keyword(s):

Phase Transitions ◽

Membrane Phase

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180. Quantitative analysis of the effect of sugars on membrane phase transitions and interlamellar hydration forces

Cryobiology ◽

10.1016/j.cryobiol.2006.10.181 ◽

2006 ◽

Vol 53 (3) ◽

pp. 443

Author(s):

Thomas Lenné ◽

Gary Bryant ◽

Karen L. Koster ◽

Roland Holcomb

Keyword(s):

Phase Transitions ◽

Quantitative Analysis ◽

Membrane Phase ◽

Hydration Forces

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Pulsed cytochrome c oxidase from the thermophilic bacterium PS3

Biochemical Journal ◽

10.1042/bj2230809 ◽

1984 ◽

Vol 223 (3) ◽

pp. 809-813 ◽

Cited By ~ 14

Author(s):

N Sone ◽

A Naqui ◽

C Kumar ◽

B Chance

Keyword(s):

Enzyme Activity ◽

Absorption Spectrum ◽

Cytochrome C ◽

Cytochrome C Oxidase ◽

Oxidase Activity ◽

Thermophilic Bacterium ◽

Decay Process ◽

Mitochondrial Enzyme ◽

Bovine Heart ◽

Enhanced Activity

A caa3-type terminal cytochrome c oxidase (EC 1.9.3.1) from the thermophilic bacterium PS3 containing three subunits showed conversion from resting into pulsed form. Upon pulsing (reduction and re-oxidation), the cytochrome c oxidase activity increased over 10-fold. This enhanced activity of the pulsed enzyme gradually decayed. Addition of phospholipids, necessary for the enzyme activity, did not affect this decay process. Small changes in the absorption spectrum were observed for the resting-into-pulsed transition and for H2O2 ligation to the pulsed enzyme. The e.p.r. spectrum of the resting enzyme was very similar to that of mitochondrial enzyme, but the transient g = 5, 1.78 and 1.69 set of e.p.r. signals, associated with the pulsed bovine heart oxidase, were not observed in the case of pulsed bacterium-PS3 enzyme.

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