title: Protein synthesis initiation factor 2 from chicken reticulocytes: purification by affinity chromatography and preliminary characterization.
abstract: Affinity chromatography on beta,gamma-methylene guanosine 5'-triphosphate-Sepharose was used to purify protein synthesis initiation factor eIF-2 from chicken reticulocytes. Gel filtration of the purified factor gave a molecular weight of 150,000, whereas electrophoresis of the purified factor on polyacrylamide gel containing sodium dodecyl sulfate revealed three non-identical subunits with apparent molecular weight of 57,000, 41,000 and 33,000. With Met-tRNA and GTP, the factor formed a ternary complex which would bind the 40S ribosomal subunits. Treatment of the factor with N-ethylmaleimide resulted in a loss of activity. Two sulfhydryl groups per eIF-2 molecule were essential for activity.
mesh_terms: D000818:Animals; D002645:Chickens; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D005033:Ethylmaleimide / Q000494:pharmacology; D015852:Eukaryotic Initiation Factor-2; D010448:Peptide Initiation Factors / Q000302:isolation & purification* / Q000378:metabolism; D011506:Proteins / Q000302:isolation & purification* / Q000378:metabolism; D012156:Reticulocytes / Q000032:analysis*
chemical_list: D015852:Eukaryotic Initiation Factor-2; D010448:Peptide Initiation Factors; D011506:Proteins; D005033:Ethylmaleimide