title: Purification and partial characterization of small proteoglycans I and II, bone sialoproteins I and II, and osteonectin from the mineral compartment of developing human bone.
abstract: Using nondegradative isolation procedures we purified and characterized five major noncollagenous proteins from developing human bone. Small bone proteoglycan I, Mr approximately 350,000 on sodium dodecyl sulfate (SDS), 4-20% gradient polyacrylamide gels has a different amino-terminal sequence of NH2-Asp-Glu-Glu-()-Gly-Ala-Asp-Thr and is not cross-reactive with the small bone proteoglycan II, Mr approximately 200,000 on SDS-gradient polyacrylamide gels. Bone proteoglycan II is 95% N terminally blocked and the small amount that can be sequenced has an amino-terminal sequence (NH2-Asp-Glu-Ala-()-Gly-Ile. . .) that is apparently similar but not identical to a small proteoglycan isolated by Brennan, M.J., Oldberg, A., Pierschbacher, M.D., and Ruoslahti, E. (1984) J. Biol. Chem. 259, 13742-13750 from human fetal placenta membrane. Two bone sialoproteins, each of which migrates at a Mr approximately 80,000 on SDS gels, have also been isolated. Bone sialoprotein I has an amino-terminal sequence of NH2-Ile-Pro-Val-Lys-Gln-Ala. . . which is different from that of bone sialoprotein II with an amino-terminal sequence of NH2-Phe-Ser-Met-Lys-Asn-Leu. . . The two bone sialoproteins do not cross-react on Western blot analysis. Human bone osteonectin contains a large number of cysteines, more than 90% of which appear to be in disulfide bonds. The N-terminal amino acid sequence of human bone osteonectin was nearly identical to bovine bone osteonectin and had many similarities to a protein found in mouse parietal endoderm (Mason, I.J., Taylor, A., Williams, J.G., Sage, H., and Hogan, B.L.M. (1986) EMBO J. 5, 1831-1837.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001846:Bone Development; D001842:Bone and Bones / Q000032:analysis*; D002352:Carrier Proteins / Q000302:isolation & purification*; D002852:Chromatography, Ion Exchange / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D004622:Embryo, Mammalian; D006801:Humans; D008970:Molecular Weight; D015676:Osteonectin; D011509:Proteoglycans / Q000302:isolation & purification*; D012795:Sialoglycoproteins / Q000302:isolation & purification*
chemical_list: D000596:Amino Acids; D002352:Carrier Proteins; D015676:Osteonectin; D011509:Proteoglycans; D012795:Sialoglycoproteins