Autogenous control of ribosomal protein synthesis in E. coli

The demand for r-proteins is growth rate dependent (high demand during rapid growth, low demand during slow growth). It is also closely coupled. R-protein synthesis is regulated at the level of translation. Which is shown by transforming E. coli with a high copy plasmid encoding r-protein. ─ mRNA level increases greatly, but not the amount of r-protein. Ribosomal protein genes are organised into several operons, each containing up to 11 genes for r-proteins. Some of these operons also encode non-ribosomal proteins whose synthesis is growth rate dependent.