Isolation and Properties of Crystalline Initiation Factor F1 from Escherichia coli Ribosomes

Initiation factro F1 was isolated from Escherichia coli ribosomes as a crystalline basic protein of molecular weight 9400 ± 100 daltons. It contains all of the common twenty amino acids, with only one residue eachy of histidien, proline, cryteine, methionine, and tryptophan, and has alanine and lysine, respectively, at the amino‐and carboxy‐terminal ends.