title: Biological ion exchanger resins; IX. Isolation and partial identification of a potassium sensitive contractile-like protein from E. coli.
abstract: A protein fraction with actin-like characteristics has been isolated from E. coli. The fraction (referred to as A-L fraction) undergoes reversible increases in molecular weight under the same catalytic conditions that polymerize actin, exhibits a distinct peak on SDS electrophoresis at the characteristic molecular weight for actin, depends primarily on potassium for its polymerization, and is not "polymerized" by sodium. A-L fraction in the monomeric form was eluted  in the void volume of a Sepharose 6B column, suggesting a large Stoke's radius and a molecular weight in excess of 400,000. The fraction contained 30% RNA by weight that proved refractory to experimental efforts at removal.
mesh_terms: D000199:Actins; D003285:Contractile Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism*; D007475:Ion Exchange Resins; D046911:Macromolecular Substances; D008274:Magnesium / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology*; D011485:Protein Binding; D012964:Sodium / Q000494:pharmacology
chemical_list: D000199:Actins; D003285:Contractile Proteins; D007475:Ion Exchange Resins; D046911:Macromolecular Substances; D012964:Sodium; D008274:Magnesium; D011188:Potassium