caa a22 4500 445298316 CHVBK 20180317142548.0 cr unu---uuuuu 170323e20100501xx s 000 0 eng 10.1007/s12013-010-9078-z doi (NATIONALLICENCE)springer-10.1007/s12013-010-9078-z The Effects of Copper (II) Ions on Enterococcus hirae Cell Growth and the Proton-Translocating FoF1 ATPase Activity [Elektronische Daten] [Zaruhi Vardanyan, Armen Trchounian] Enterococcus hirae grow well under anaerobic conditions at alkaline pH (pH 8.0) producing acids by glucose fermentation. Bacterial growth was shown to be accompanied by decrease of redox potential from positive values (~+35mV) to negative ones (~−220mV). An oxidizer copper (II) ions (Cu2+) affected bacterial growth in a concentration-dependent manner (within the range of 0.05mM to 1mM) increasing lag phase duration and decreasing specific growth rate. These effects were observed with the wild-type strain ATCC9790 and the atpD mutant strain MS116 (with absent β subunit of F1 of the FoF1 ATPase) both. Also ATPase activity and proton-potassium ions exchange were assessed with and without N,N′-dicyclohexylcarbodiimide (DCCD), inhibitor of the FoF1 ATPase. In both cases (DCCD ±), even low Cu2+ concentrations had noticeable effect on ATPase activity, but with less visible concentration-dependent manner. Changes in the number of accessible SH-groups were observed with E. hirae ATCC9790 and MS116 membrane vesicles. In both strains Cu2+ markedly decreased the number of SH-groups in the presence of K+ ions. The addition of ATP increased the amount of accessible SH-groups in ATCC9790 and decreased this number in MS116; Cu2+ blocked ATP-installed increase in SH-groups number in ATCC9790. H+-K+-exchange of bacteria was markedly inhibited by Cu2+, but stronger effects were detected together with DCCD. Moreover, discrimination between Cu2+ and other bivalent cation—Ni2+ was shown. It is suggested that Cu2+ ions inhibit E. hirae cell growth by direct affect on the FoF1 ATPase leading to conformational changes in this protein complex and decrease in its activity. Springer Science+Business Media, LLC, 2010 Cu2+ nationallicence Bacterial growth nationallicence Proton transport nationallicence FoF1 ATPase nationallicence SH-groups nationallicence Enterococcus hirae nationallicence Vardanyan Zaruhi Department of Biophysics of the Biological Faculty, Yerevan State University, 1 A. Manoukian Str, 0025, Yerevan, Armenia aut Trchounian Armen Department of Biophysics of the Biological Faculty, Yerevan State University, 1 A. Manoukian Str, 0025, Yerevan, Armenia aut Cell Biochemistry and Biophysics Humana Press Inc 57/1(2010-05-01), 19-26 1085-9195 57:1<19 2010 57 12013 https://doi.org/10.1007/s12013-010-9078-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12013-010-9078-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Vardanyan Zaruhi Department of Biophysics of the Biological Faculty, Yerevan State University, 1 A. Manoukian Str, 0025, Yerevan, Armenia aut NATIONALLICENCE 700 1- Trchounian Armen Department of Biophysics of the Biological Faculty, Yerevan State University, 1 A. Manoukian Str, 0025, Yerevan, Armenia aut NATIONALLICENCE 773 0- Cell Biochemistry and Biophysics Humana Press Inc 57/1(2010-05-01), 19-26 1085-9195 57:1<19 2010 57 12013 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer