The Swelling of Spores of Bacillus subtilis During Germination

Abstract

The swelling of spores of Bacillus subtilis during germination was followed by measuring changes in the cell volume by means of the Coulter Counter method. It is generally recognized that there are three stages of swelling: (1) germination swelling involving a rapid increase of cell volume as the spore germinated, (2) pre-emergence swelling of cell volume before emergence from the spore coat, and (3) elogation. The spore volume increased about 30% after 40 min of germination in the Demain's germination medium. to confirm the accuracy in sizing by the Coulter Counter method, electron microscopic observation was done. The two results coincided.