Abstract DNA gyrase, a type II topoisomerase found predominantly in bacteria, is the target for variety of ‘poisons’, namely natural product toxins (e.g. albicidin, microcin B17) and clinically important synthetic molecules fluoroquinolones). Resistance to both groups can be mediated by pentapeptide repeat proteins (PRPs). Despite long-term studies, mechanism action these protective PRPs not kn...

The newly identified specific V-ATPase inhibitor, salicylihalamide A, is distinct from any previously identified V-ATPase inhibitors in that it inhibits only mammalian V-ATPases, but not those from yeast or other fungi (Boyd, M. R., Farina, C., Belfiore, P., Gagliardi, S., Kim, J. W., Hayakawa, Y., Beutler, J. A., McKee, T. C., Bowman, B. J., and Bowman, E. J. (2001) J. Pharmacol. Exp. Ther. 29...

Mycobacterium tuberculosis and Staphylococcus aureus secrete virulence factors via type VII protein secretion (T7S), a system that intriguingly requires all of its secretion substrates for activity. To gain insights into T7S function, we used structural approaches to guide studies of the putative translocase EccC, a unique enzyme with three ATPase domains, and its secretion substrate EsxB. The ...

Mussels are effective bioindicator organisms for aquatic environments. Therefore, they were often used to determine the effects of various xenobiotics in systems. There is no study our knowledge on vivo nanoparticles (NPs) activities ATPases freshwater mussels (Unio tigridis). This work demonstrates Al$_{2}$O$_{3}$, CuO, and TiO$_{2}$ NPs Na- ATPase, Ca-ATPase, Mg-ATPase gill muscle following 1...

F-type ATPases are highly conserved enzymes used primarily for the synthesis of ATP. Here we apply mass spectrometry to the F1FO-ATPase, isolated from spinach chloroplasts, and uncover multiple modifications in soluble and membrane subunits. Mass spectra of the intact ATPase define a stable lipid 'plug' in the FO complex and reveal the stoichiometry of nucleotide binding in the F1 head. Compari...

This paper describes the role of α-subunit VISIT-DG sequence residue αThr-349 in the catalytic sites of Escherichia coli F1Fo ATP synthase. X-ray structures show the highly conserved αThr-349 in the proximity (2.68 Å) of the conserved phosphate binding residue βR182 in the phosphate binding subdomain. αT349A, -D, -Q, and -R mutations caused 90-100-fold losses of oxidative phosphorylation and re...

The activity of P-type plasma membrane H(+)-ATPases is modulated by H(+) and cations, with K(+) and Ca(2+) being of physiological relevance. Using X-ray crystallography, we have located the binding site for Rb(+) as a K(+) congener, and for Tb(3+) and Ho(3+) as Ca(2+) congeners. Rb(+) is found coordinated by a conserved aspartate residue in the phosphorylation domain. A single Tb(3+) ion is ide...

We have recently isolated a mutant (aK220R, aV264E, aI278N) of the Na+-translocating Escherichia coli/Propionigenium modestum ATPase hybrid with a Na+-inhibited growth phenotype on succinate. ATP hydrolysis by the reconstituted mutant ATPase was inhibited by external (N side) NaCl but not by internal (P side) NaCl. In contrast, LiCl activated the ATPase from the N side and inhibited it from the...

P-type ATPases are a large family of enzymes that actively transport ions across biological membranes by interconverting between high (E1) and low (E2) ion-affinity states; these transmembrane transporters carry out critical processes in nearly all forms of life. In striated muscle, the archetype P-type ATPase, SERCA (sarco(endo)plasmic reticulum Ca(2+)-ATPase), pumps contractile-dependent Ca(2...