The formation of N-formyl-methionyl-sRNA

Abstract

The reaction between methionine and its specific sRNA of Escherichia coli has been further investigated. Previous investigations have shown that this reaction leads to the formation of methionyl-sRNA and N-formyl-methionyl-sRNA. In this paper, evidence is presented which shows that the formylation of the α-amino group of methionine only occurs after methionine has become attached to its specific sRNA. The formyl-donor in the conversion of methionyl-sRNA to N-formyl-methionyl-sRNA is most likely a derivative of formyl-tetrahydrofolio acid. Experiments are presented which suggest that sRNA of E. coli contains two different methionine-accepting sRNA's, of which only one can be converted into the formyl-derivative.