title: Physical properties of Artemia salina ribosomes.
abstract: Eukaryotic ribosomes were isolated from the cryptobiotic embryos and from the further-developed free-swimming nauplii of the brine shrimp Artemia salina. Analytical boundary sedimentation and photon correlation spectroscopy yielded, respectively, the standard sedimentation and diffusion coefficients at infinite dilution, s degrees 20,w = 81 +/- 1 S and D degrees 20,w = (1.41 +/- 0.02) x 10(-7) cm2/s, for the unfixed and formaldehyde-fixed ribosomes from different developmental stages and for ribosomes attached to a messenger RNA fragment. Also, the density increment was determined, from which the partial specific volume was derived (0.63 +/- 0.01 cm3/g). Combination of the different measured parameters gives accurate values for the molecular weight (3.8 +/- 0.1) x 106 and for size and solvation parameters. These results are compared with their counterparts for the smaller ribosomes from the prokaryote Escherichia coli.
mesh_terms: D000818:Animals; D002458:Cell Fractionation / Q000379:methods; D033364:Decapoda; D004926:Escherichia coli / Q000648:ultrastructure; D008433:Mathematics; D008970:Molecular Weight; D012270:Ribosomes / Q000648:ultrastructure*; D014461:Ultracentrifugation