A method for investigating electrogenic partial reactions in the pump cycle of membrane-bound P-type ATPases with electrochromic fluorescent dyes has been extended to detergent-solubilized native and purified recombinant Na,K-ATPase. As a first step, it has been shown here that the function and ion binding properties of the detergent-soluble and membrane-bound rabbit renal Na,K-ATPase are not s...

We have determined the structure of the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) in an E2.P(i)-like form stabilized as a complex with MgF(4)(2-), an ATP analog, adenosine 5'-(beta,gamma-methylene)triphosphate (AMPPCP), and cyclopiazonic acid (CPA). The structure determined at 2.5A resolution leads to a significantly revised model of CPA binding when compared with earlier reports. It s...

Trinitrophenyl derivatives of adenine nucleotides are widely used for probing ATP-binding sites. Here we describe crystal structures of Ca(2+)-ATPase, a representative P-type ATPase, in the absence of Ca(2+) with bound ATP, trinitrophenyl-ATP, -ADP, and -AMP at better than 2.4-Å resolution, stabilized with thapsigargin, a potent inhibitor. These crystal structures show that the binding mode of ...

In this work, we demonstrate that the phosphatidylinositol 3,4,5-trisphosphate-binding protein JFC1 is an ATP-binding protein with magnesium-dependent ATPase activity. We show that JFC1 specifically binds to the ATP analog 8-azido-[alpha-(32)P]ATP. The affinity of JFC1 for [alpha-(32)P]ATP was 10x greater than its affinity for [alpha-(32)P]ADP; the protein did not appear to bind to [alpha-(32)P...

Aim: This study aimed to predict the molecular targets of cipargamin in humans and estimate structural dynamics binding affinity their interactions compared that Plasmodium falciparum P-type ATPase 4 (PfATP4). Methods: In silico methods were used this which include target prediction, structure modeling dynamics, docking. Results: The results showed had 100% probability human adenosine A3 recept...

P-glycoprotein (P-gp) is a membranous ATPase responsible for the multidrug resistance (MDR) phenotype. Using membrane vesicles prepared from the highly resistant cell line DC-3F/ADX we studied the influence of P-gp ATPase activity of four progesterone derivatives which specifically bind to P-gp and reverse MDR. Progesterone and desoxycorticosterone stimulate P-gp ATPase activity with, respectiv...

The H,K-ATPase responsible for gastric acidification is a heterodimeric (alpha and beta subunit) P-type ATPase, an integral protein of parietal cell apical membranes, which promotes the electroneutral exchange of K+ for protons, is stimulated by K+ and is inhibited by 2-methyl-8-(phenylmethoxy)imidazo[1, 2-alpha]pyridine-3-acetonitrile (SCH 28080). Hydropathy analysis of the catalytic alpha sub...

Objective(s): This study was designed to investigate various gastrointestinal effects of Manilkara zapota (Sapodilla), exploring its anti-diarrheal, anti-secretary, anti-spasmodic, anti-ulcer and anti-motility potential.Materials and Methods: Antidiarrheal and anti-secretary activities were investigated using castor oil induced diarrhea ...