کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1924910 1536324 2015 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Impact of membrane-associated hydrogenases on the FOF1-ATPase in Escherichia coli during glycerol and mixed carbon fermentation: ATPase activity and its inhibition by N,N′-dicyclohexylcarbodiimide in the mutants lacking hydrogenases
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Impact of membrane-associated hydrogenases on the FOF1-ATPase in Escherichia coli during glycerol and mixed carbon fermentation: ATPase activity and its inhibition by N,N′-dicyclohexylcarbodiimide in the mutants lacking hydrogenases
چکیده انگلیسی


• ATPase activity was studied in E. coli during glycerol and mixed carbon (glucose and glycerol) fermentation.
• It was investigated using different mutants lacking membrane-associated hydrogenases (Hyd).
• ATPase activity was changed in mutants depending on pH; it was inhibited by N,N′-dicyclohexylcarbodiimide.
• pH 7.5 is optimal for the FOF1-ATPase; Hyd-1, Hyd-2 are required for FOF1 upon glycerol.
• A relationship of FOF1 with Hyd-1 and Hyd-2 is obvious upon mixed carbon at pH 6.5.

Escherichia coli is able to ferment glycerol and to produce molecular hydrogen (H2) by four membrane-associated hydrogenases (Hyd) changing activity in response to different conditions. In this study, overall ATPase activity of glycerol alone and mixed carbon sources (glucose and glycerol) fermented E. coli wild type and different Hyd mutants and its inhibition by N,N′-dicyclohexylcarbodiimide (DCCD) were first investigated. ATPase activity was higher in glycerol fermented wild type cells at pH 7.5 compared to pH 6.5 and pH 5.5; DCCD inhibited markedly ATPase activity at pH 7.5. The ATPase activity at pH 7.5, compared with wild type, was lower in selC and less in hypF single mutants, suppressed in hyaB hybC selC triple mutant. Moreover, total ATPase activity of mixed carbon fermented wild type cells was maximal at pH 7.5 and lowered at pH 5.5. The ATPase activities of hypF and hyaB hybC selC mutants were higher at pH 5.5, compared with wild type; DCCD inhibited markedly ATPase activity of hypF mutant. These results demonstrate that in E. coli during glycerol fermentation the membrane proton-translocating FOF1-ATPase has major input in overall ATPase activity and alkaline pH is more optimal for the FOF1-ATPase operation. Hyd-1 and Hyd-2 are required for the FOF1-ATPase activity upon anaerobic fermentation of glycerol. The impact of Hyd-1 and Hyd-2 on the FOF1-ATPase is more obvious during mixed carbon fermentation at slightly acidic pH.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Archives of Biochemistry and Biophysics - Volume 579, 1 August 2015, Pages 67–72
نویسندگان
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