Copper ATPase CopA from Escherichia coli: Quantitative Correlation between ATPase Activity and Vectorial Copper Transport
Chathuri JK Wijekoon, Saumya R Udagedara, Roland L Knorr, Rumiana Dimova, Anthony G Wedd, Zhiguang Xiao
Journal of the American Chemical Society | American Chemical Society | Published : 2017
Cu-ATPases are membrane copper transporters present in all kingdoms of life. They play a central role in Cu homeostasis by pumping Cu ions across cell membranes with energy derived from ATP hydrolysis. In this work, the Cu-ATPase CopA from Escherichia coli was expressed and purified in fully functional form and demonstrated to bind Cu(I) with subfemtomolar affinity. It was incorporated into the lipid membrane of giant unilamellar vesicles (GUVs) whose dimensions match those of eukaryotic cells. An 1H NMR approach provided a quantitative ATPase activity assay for the enzyme either dissolved in detergent or embedded in GUV membranes. The activity varied with the Cu(I) availability in an optimi..View full abstract
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Awarded by Australian Research Council
This work was supported by the Australian Research Council (Grant DP130100728) and is part of the MaxSynBio consortium, which is jointly funded by the Federal Ministry of Education and Research of Germany and the Max Planck Society. Some of the confocal images were recorded at the microscopy platform of the Bio21 Institute. Professor Svetlana Lutsenko (Johns Hopkins University) and Professor Ashley Bush (the Florey Institute) are thanked for comments and discussions.