Bulk properties of the lipid bilayer are not essential for the thermal stability of Na,K-ATPase from shark rectal gland or pig kidney

Biochem Biophys Res Commun. 2011 Mar 25;406(4):580-3. doi: 10.1016/j.bbrc.2011.02.094. Epub 2011 Feb 23.

Abstract

The thermal stability of Na,K-ATPase from pig kidney is markedly greater than that of Na,K-ATPase from shark salt glands. The role of the lipid bilayer is studied by solubilisation of the membrane-bound enzyme in the nonionic detergent octaethyleneglycoldodecylmonoether (C(12)E(8)), addition of excess dioleylphosphatidylcholine (DOPC) or palmitoyloleylphosphatidylcholine (POPC) and reconstitution of membranes by removal of detergent. At 54°C the reconstituted enzymatically active pig enzyme retains a high thermal stability, and reconstituted shark enzyme retains a low thermal stability, even with a 9-fold excess of DOPC. This result suggests that the origin of the difference in thermal stability is not related to bulk lipid properties of the native membranes.

MeSH terms

  • Animals
  • Enzyme Stability
  • Hot Temperature*
  • Kidney / enzymology*
  • Lipid Bilayers / chemistry*
  • Phosphatidylcholines / chemistry
  • Salt Gland / enzymology*
  • Sharks
  • Sodium-Potassium-Exchanging ATPase / chemistry*
  • Swine

Substances

  • Lipid Bilayers
  • Phosphatidylcholines
  • Sodium-Potassium-Exchanging ATPase
  • 1,2-oleoylphosphatidylcholine