Open AccessFunctional Identity of the Monomeric and Multiple Forms of Elongation‐Factor 1 from Krebs‐II Mouse‐Ascites‐Tumor Cells
Author(s) -
GRASMUK Hans,
NOLAN Robert D.,
DREWS Jürgen
Publication year - 1976
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1976.tb10707.x
Subject(s) - ribosome , monomer , enzyme , biochemistry , guanosine triphosphate , size exclusion chromatography , eukaryotic translation elongation factor 1 alpha 1 , nucleotide , chemistry , guanosine , protein biosynthesis , biology , stereochemistry , gtp' , rna , organic chemistry , gene , polymer
Highly purified 3 H‐labelled elongation factor 1 (EF‐1) from Krebs II mouse ascites tumour cells was separated into biologically active monomeric and aggregate forms of the enzyme by either gradient centrifugation or gel filtration. When corrected for their content of inactive enzyme both forms of the factor were found to he equally active whether tested in the binding or synthesis reaction. The only form of the enzyme found bound to ribosomes was the monomer; it was therefore concluded that the aggregate form of the enzyme must first dissociate before it reacts with the ribosome. The stoichiometry of the aminoacyl‐tRNA binding reaction to ribosomes in the presence of.guanosine nucleotides was also studied. It was found that one molecule of aminoacyl‐tRNA and of Guo‐5′‐P 2 ‐CH 2 ‐P is bound per molecule of EF‐1 bound to the ribosome. Following interaction with and release from, the ribosomes, EF‐1 was found to be predominantly monomeric.