title: Molecular weights and hydrophobicity of the polypeptide chain of sarcoplasmic reticulum calcium(II) adenosine triphosphatase and of its primary tryptic fragments.
abstract: The polypeptide chain of the Ca2+-stimulated adenosine triphosphatase from sarcoplasmic reticulum has a molecular weight of 119 000+/-6500 on the basis of sedimentation equilibrium measurements in sodium dodecyl sulfate. The two primary fragments obtained by limited proteolysis each have within experimental error the same molecular weight, corresponding to one-half the molecular weight of the whole chain. Both fragments are eqaully resistant to complete denaturation by guanidine hydrochloride, a property characteristic of many intrinsic membrane proteins. This suggests that the native enzyme has two membrane-embedded halves, with an externally accessible link between them.
mesh_terms: D000251:Adenosine Triphosphatases / Q000302:isolation & purification / Q000378:metabolism; D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000494:pharmacology*; D002850:Chromatography, Gel; D002942:Circular Dichroism; D004789:Enzyme Activation / Q000187:drug effects; D008970:Molecular Weight; D010446:Peptide Fragments / Q000302:isolation & purification / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D012519:Sarcoplasmic Reticulum / Q000201:enzymology*; D012967:Sodium Dodecyl Sulfate; D014357:Trypsin
chemical_list: D010446:Peptide Fragments; D012967:Sodium Dodecyl Sulfate; D014357:Trypsin; D000251:Adenosine Triphosphatases; D002118:Calcium