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Incorporation of different amino acids into the proteins of wheat embryo has been found to be not uniform during the various stages of seed germination. It is suggested that incorporation maxima of appropriate amino acids can be used as markers of switching of specific protein synthesis during embryo development. Such markers have been found suitable for defining the functional activity of preformed messenger RNA.

Some characteristics of the translation process during amino acid starvation in Escherichia coli have been examined. Once starvation has been established, premature termination of polypeptides is negligible and complete proteins are formed. There is some preference for the synthesis of shorter proteins. The number of ribosomes involved in protein synthesis appears to decline to about half during amino acid-starvation. The assembly time of proteins during amino acid starvation is increased to only about fourfold, though protein synthesis maintained by turnover is reduced to 10%. To explain these observations, a model has been proposed for the course of events that possibly take place from the onset of starvation.