GLYCOGEN IN BACILLUS-SUBTILIS - MOLECULAR CHARACTERIZATION OF AN OPERON ENCODING ENZYMES INVOLVED IN GLYCOGEN BIOSYNTHESIS AND DEGRADATION

Although it has never been reported that Bacillus subtilis is capable of accumulating glycogen, we have isolated a region from the chromosom e of B. subtilis containing a glycogen operon. The operon is located d irectly downstream from trnB, which maps at 275 degrees on the B. subt ilis chromosome. It encodes five polypeptides with extensive similarit y to enzymes involved in glycogen and starch metabolism in both prokar yotes and eukaryotes. The operon is presumably expressed by an E sigma (E)-controlled promoter, which was previously identified downstream fr om trnB. We have observed glycogen biosynthesis in B. subtilis exclusi vely on media containing carbon sources that allow efficient sporulati on. Sporulation-independent synthesis of glycogen occurred after integ ration of an E sigma(A) controlled promoter upstream of the operon.