oligomycins and monobromobimane

oligomycins has been researched along with monobromobimane* in 2 studies

Other Studies

2 other study(ies) available for oligomycins and monobromobimane

Article	Year
Reactivity of mitochondrial sulfhydryl groups toward dithionitrobenzoic acid and bromobimanes under oligomycin-inhibited and uncoupling conditions. Archives of biochemistry and biophysics, 1988, Volume: 266, Issue:1 Thiol reactivity was determined in rat heart mitochondria using chromophores of differing polarities: monobromobimane (MB), dithionitrobenzoate (NbS2), and bromobimane-q (MQ). The purpose of this study is to correlate reaction rates of protein thiols in the mitochondrial membrane with the oligomycin-inhibited and uncoupled states: In all cases investigated the reactivity of -SH groups toward MB decreases under the above conditions. In parallel with an increase of their uncoupling activities the uncouplers reduce the reaction rate of thiol groups toward NbS2 and, progressively, toward MQ, indicating differences in sensitivity of thiol groups to uncouplers depending on the polarity of the environment. The pattern of -SH reactivity under inhibition by oligomycin resembles that of carbonylcyanide-p-trifluoromethoxyphenylhydrazone. Functional changes of the mitochondrial membrane probably correlate with reactivity/polarity changes of membrane -SH groups. Masking of membrane thiol groups thus is not specific for uncouplers but is also observed under inhibition with oligomycin. Topics: Animals; Bridged Bicyclo Compounds; Dithionitrobenzoic Acid; Electron Spin Resonance Spectroscopy; In Vitro Techniques; Mitochondria, Heart; Oligomycins; Oxidation-Reduction; Rats; Solubility; Spin Labels; Sulfhydryl Compounds; Uncoupling Agents	1988
Bromobimane crosslinking studies in oligomycin-sensitive ATPase from beef heart mitochondria. Mr 31 000 protein crosslinked. FEBS letters, 1982, Dec-13, Volume: 150, Issue:1 Using a bromobimane fluorescent label the Mr 31 000 protein band oligomycin-sensitive (OS)-ATPase from beef heart mitochondria is shown to become much intensified by 2-mercaptopropionylglycine. In the presence of 3.5 nmol/mg protein of the thiol reagent ATP-Pi exchange activity is increased by 90%. With the fluorescent crosslinking reagent dibromobimane (DB) we show that a new fluorescent peak appears between Mr 50 000 and 60 000. ATP-Pi exchange is very much decreased by DB. The results suggest that for regulation of ATP-synthetase activity sulfhydryl groups in the region of the Mr 31 000 protein(s) play an important role. Topics: Adenosine Triphosphatases; Animals; Bridged Bicyclo Compounds; Bridged-Ring Compounds; Cattle; Cross-Linking Reagents; Electrophoresis, Polyacrylamide Gel; Fluorescent Dyes; Mitochondria, Heart; Molecular Weight; Oligomycins	1982

Article

Year

Reactivity of mitochondrial sulfhydryl groups toward dithionitrobenzoic acid and bromobimanes under oligomycin-inhibited and uncoupling conditions.

Archives of biochemistry and biophysics, 1988, Volume: 266, Issue:1

Thiol reactivity was determined in rat heart mitochondria using chromophores of differing polarities: monobromobimane (MB), dithionitrobenzoate (NbS2), and bromobimane-q (MQ). The purpose of this study is to correlate reaction rates of protein thiols in the mitochondrial membrane with the oligomycin-inhibited and uncoupled states: In all cases investigated the reactivity of -SH groups toward MB decreases under the above conditions. In parallel with an increase of their uncoupling activities the uncouplers reduce the reaction rate of thiol groups toward NbS2 and, progressively, toward MQ, indicating differences in sensitivity of thiol groups to uncouplers depending on the polarity of the environment. The pattern of -SH reactivity under inhibition by oligomycin resembles that of carbonylcyanide-p-trifluoromethoxyphenylhydrazone. Functional changes of the mitochondrial membrane probably correlate with reactivity/polarity changes of membrane -SH groups. Masking of membrane thiol groups thus is not specific for uncouplers but is also observed under inhibition with oligomycin.

Topics: Animals; Bridged Bicyclo Compounds; Dithionitrobenzoic Acid; Electron Spin Resonance Spectroscopy; In Vitro Techniques; Mitochondria, Heart; Oligomycins; Oxidation-Reduction; Rats; Solubility; Spin Labels; Sulfhydryl Compounds; Uncoupling Agents

1988

Bromobimane crosslinking studies in oligomycin-sensitive ATPase from beef heart mitochondria. Mr 31 000 protein crosslinked.

FEBS letters, 1982, Dec-13, Volume: 150, Issue:1

Using a bromobimane fluorescent label the Mr 31 000 protein band oligomycin-sensitive (OS)-ATPase from beef heart mitochondria is shown to become much intensified by 2-mercaptopropionylglycine. In the presence of 3.5 nmol/mg protein of the thiol reagent ATP-Pi exchange activity is increased by 90%. With the fluorescent crosslinking reagent dibromobimane (DB) we show that a new fluorescent peak appears between Mr 50 000 and 60 000. ATP-Pi exchange is very much decreased by DB. The results suggest that for regulation of ATP-synthetase activity sulfhydryl groups in the region of the Mr 31 000 protein(s) play an important role.

Topics: Adenosine Triphosphatases; Animals; Bridged Bicyclo Compounds; Bridged-Ring Compounds; Cattle; Cross-Linking Reagents; Electrophoresis, Polyacrylamide Gel; Fluorescent Dyes; Mitochondria, Heart; Molecular Weight; Oligomycins

1982