A kinetic study of the gill (Na+, K+)-ATPase, and its role in ammonia excretion in the intertidal hermit crab, Clibanarius vittatus.

@article{Gonalves2006AKS,
  title={A kinetic study of the gill (Na+, K+)-ATPase, and its role in ammonia excretion in the intertidal hermit crab, Clibanarius vittatus.},
  author={R{\'u}bia R. Gonçalves and Douglas Chodi Masui and John Campbell McNamara and Fernando L Mantelatto and Daniela Pereira Garçon and Rosa dos Prazeres Melo Furriel and Francisco Assis Leone},
  journal={Comparative biochemistry and physiology. Part A, Molecular & integrative physiology},
  year={2006},
  volume={145 3},
  pages={346-56}
}
To better comprehend the role of gill ion regulatory mechanisms, the modulation by Na(+), K(+), NH(4)(+) and ATP of (Na(+), K(+))-ATPase activity was examined in a posterior gill microsomal fraction from the hermit crab, Clibanarius vittatus. Under saturating Mg(2+), Na(+) and K(+) concentrations, two well-defined ATP hydrolyzing sites were revealed. ATP was hydrolyzed at the high-affinity sites at a maximum rate of V=19.1+/-0.8 U mg(-1) and K(0.5)=63.8+/-2.9 nmol L(-1), obeying cooperative… CONTINUE READING