Magnesium Suppresses Defects in the Formation of 70S Ribosomes as Well as in Sporulation Caused by Lack of Several Individual Ribosomal Proteins

We previously reported that an increase in cellular Mg 2+ content can suppress defects in 70S ribosome formation and growth rate caused by the absence of ribosomal protein L34. In the present study, we demonstrated that, even in mutants lacking individual ribosomal proteins other than L34 (L1, L23, L36, and S6), an increase in the cellular Mg 2+ content could restore 70S ribosome formation. Moreover, the defect in sporulation caused by the absence of L1 was also suppressed by an increase in the cellular Mg 2+ content. These findings indicate that at least part of the function of these ribosomal proteins can be complemented by Mg 2+ , which is essential for all living cells.