Identification of a novel biomolecule in deep-sea clams
EMSL Project ID
2630
Abstract
Marine invertebrates are osmoconformers and must match their intracellular osmotic pressure to the high osmotic pressure of seawater. Compatible organic osmolytes that do not disrupt proteins are used to create this balance. In addition to elevating cell osmotic pressure, some osmolytes have been shown to stabilize proteins against certain perturbation. In cartilaginous fishes, the osmolyte trimethylamine-N-oxide (TMAO) counteracts the protein-destabilizing effects of the osmolyte urea (Yancey, Clark, Hand, Bowlus & Somero, Science 217:1214,1982). This finding led to the discovery that mammalian/human kidney cells protect their proteins from urea (a major urinary waste product) by using the methylamine glycerophosphorylcholine (GPC). Methylamines and other osmolyte-like molecules are being explored as stabilizers of macromolecules in biotechnological and medical applications (Yancey, Amer. Zool., 41:699, 2001).Recently, we found that TMAO content increases with depth in the ocean in fish and crustaceans down to 3000 m. We also found that TMAO can stabilize proteins against the perturbations of high pressure in the deep (Yancey, ibid, 2001). Now we have found an apparently novel biomolecule in clams from even greater depths; the molecule increases linearly in content with depth to 6400 m. It replaces the common osmolytes of shallow clams, taurine and glycine (FIGURE 1 attachment to proposal). This unknown is the most concentrated biomolecule in these clams and is thus their main osmolyte. It may also serve to stabilize proteins under pressure, since it seems to resemble the stabilizer GPC. We isolated the compound by ion-exchange HPLC; preliminary work with NMR at W.S.U. indicates that it contains serine, phosphate and ethanolamine and another unidentified moiety. We now need to identify the molecular weight and major molecular components of the solute, using mass spectrometry and other relevant techniques.??
Project Details
Project type
Exploratory Research
Start Date
2002-09-03
End Date
2004-01-08
Status
Closed
Released Data Link
Team
Principal Investigator