Endospore Formation Stage 2- Spore Septum Formation - Inward growth of a double layer of the cell membrane, possibly from the mesosome, takes place near one end of the cell. The ceI1 is asymmetrically partitioned by the double membrane, which forms a transverse spore septum. The nuclear material divides so that each compartment contains at least one complete chromosome. The spore septum divides the bacterial cell into a smaller and a larger compartment, each containing DNA. The smaller compartment is called the forespore, while the larger compartment is the mother cell.
The sporulation septum has no peptidoglycan layer between the invaginating membrane in most organisms. In Bacillus sphaericus, however, peptidoglycan-like material has been observed. The mesosomes have been found to be associated with the asymmetric division of sporulation. Synthesis of alanine dehydrogenase takes place during this stage.