Biochemical Processes in the Simplest Structures 



433 



of amino acids into the protein of the protoplasts under study is indeed one of 

 the possible stages of the synthesis of protein, as suggested by Gale [6] and 

 Borsook [7]. Energy is required for this reaction, as indicated by its suppression 

 with 2 : 4-dinitrophenol and sodium azide. However, the amount of energy 

 needed is probably not great since incorporation still continues at those levels 

 of destruction of the cell at which the protoplasts exhibit a low intensity of the 

 respiratory process. 



0-84 074 0-64 0-54 0-44 0-34 0-24 



Sucrose molar 

 Fig. 4. Respiration of protoplasts (II) of M. lysodeikticus 

 and incorporation of labelled glycine (I). 



With the aim of ascertaining the sources of energy for the process of incorpora- 

 tion we determined some fractions of soluble phosphorus compounds in the 

 filtrates obtained upon precipitation of the protoplasts with trichloroacetic acid. 

 The mineral P (orthophosphate) and the 'y-minute P' (after hydrolysis for 

 7 minutes with N-HCl) were determined. The phosphorus was estimated by 



Table 3 



Assimilation of mineral phosphate during 120 minutes by protoplasts 



obtained at different sucrose concentrations 



Results expressed as /ig P in the total volume of the reaction mixture (i ml) 



28 



