title: Membrane ATPase of Proteus L-forms. Solubilization and molecular properties.
abstract: The Mg2+ -dependent ATPase (EC 3.6.I.3) of Proteus L-form membrane has been solubilized according to various procedures (Tris - HCL shock-wash with or without MG2+, EDTA, Triton X-100). The best results were obtained by the same 33mM Tris-HCL (pH 7.5) shock-wash without MG2+ used for ATPase of protoplasts from Streptococcus faecalis. The solubilized enzyme after 105 000 times g centrifugation was purified on acrylamide/agarose. The molecular weight was established to be 360 000 by gel filtration and by sedimentation coefficient (12.5 S). Polyacrylamide disc-gel electrophoresis in sodium dodecylsulphate revealed two classes or subunit of mol. wt. 64 000 (alpha) and 58 000 (beta), associated in ratio 1:1. We propose a formula alpha-3beta-3 for the native ATPase of Proteus L-forms. Structural similarities to ATPase of various origins are discussed.
mesh_terms: D000251:Adenosine Triphosphatases / Q000302:isolation & purification / Q000378:metabolism; D000596:Amino Acids / Q000032:analysis; D002462:Cell Membrane / Q000201:enzymology; D002850:Chromatography, Gel; D004492:Edetic Acid; D004589:Electrophoresis, Disc; D004789:Enzyme Activation / Q000187:drug effects; D008274:Magnesium / Q000494:pharmacology; D008970:Molecular Weight; D011092:Polyethylene Glycols; D011511:Proteus / Q000201:enzymology*; D012995:Solubility
chemical_list: D000596:Amino Acids; D011092:Polyethylene Glycols; D004492:Edetic Acid; D000251:Adenosine Triphosphatases; D008274:Magnesium