Sulfur Compounds in RNA Fraction from Sporulating Cells of Bacillus subtilis

As we reported previously, in the sporulating cells of Bacillus subtilis about 20% of intracellular sulfur is found in the nucleic acid fraction. In the present work further characterization of sulfur compounds in this fraction was made using tracer technique and MAK column chromatography, and changes in pattern of the sulfur compounds during sporulation was observed.

It was found that the greater part of sulfur in the nucleic acid fraction was present as methionine and cysteine, which were associated with tRNA throughout the growth and sporulation. The amount of methionine as methionine tRNA was larger than that of cysteine as cysteine tRNA in the vegetative cells and vice versa in the sporulating cells.