Process for producing extract for cell-free protein synthesis and cell extract produced thereby

Abstract

It is intended to provide a process for producing an extract for cell-free protein synthesis whereby the productivity of a protein and the production efficiency can be improved. Cells are cultured under suppressed growth conditions. In the stationary phase of the culture, the cells are collected and then disrupted. The above-described cells are preferably bacterial cells, in particular, Escherichia coli cells. In the suppressed growth conditions as described above, the culture temperature is preferably from 20 to 32° C., more preferably 26° C. or higher and lower than 30° C.

1 . A cell-free protein synthesis extract prepared by a process comprising:
 culturing a bacterial cell under a suppressed growth condition that is culture at a temperature form from 20° C. to 32° C.,   harvesting the cell at a stationary phase in said culture, and   disrupting said harvested cell to obtain an extract having cell-free protein synthesis activity.   
     
     
         2 . A cell-free protein synthesis extract prepared by a process comprising:
 culturing  Escherichia coli  cells under a suppressed growth condition that is culture at a temperature form from 20° C. to 32° C.,   harvesting the  Escherichia coli  cells at a stationary phase in said culture, and   preparing a S30 extract having cell-free protein synthesis activity from said harvested  Escherichia coli  cells.   
     
     
         3 . The Extract according to  claim 1  or  claim 2  wherein said extract is prepared by a process wherein said suppressed growth condition is a culture condition that is culture at a temperature of not lower than 26° C. and lower than 30° C. 
     
     
         4 . The extract according to  claim 1  or  claim 2 , comprising ribosomes that have an improved stability and/or an increased protein synthetic activity per unit ribosome amount of ribosome.