@article{mbs:/content/journal/micro/10.1099/00221287-17-2-525, author = "Strange, R. E. and Dark, F. A.", title = "Cell-Wall Lytic Enzymes at Sporulation and Spore Germination in Bacillus Species", journal= "Microbiology", year = "1957", volume = "17", number = "2", pages = "525-537", doi = "https://doi.org/10.1099/00221287-17-2-525", url = "https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-17-2-525", publisher = "Microbiology Society", issn = "1465-2080", type = "Journal Article", abstract = "SUMMARY: When washed sporulating cells of Bacillus cereus were incubated in buffer at 37° in the presence of toluene, a partial autolysis occurred resulting in the freeing of mature and immature spores. The autolysate contained lytic enzymes which attacked vegetative cells and cell-wall preparations, releasing hexosamine- containing peptides of characteristic constitution. The most active enzyme preparations were obtained from sporulating cells incubated for 1–2 hr. in buffer at pH 5·0–6·0. Two water-soluble lytic systems, enzyme V and enzyme S with pH optima near 4·5 and 8·0 respectively, were separated from the autolysate. Enzyme S is probably identical with the lytic system present in spores of B. cereus and other Bacillus species and further observations on this system are described. When non-sporulating cells of B. cereus were incubated under similar conditions no obvious lysis or sporulation occurred and no cell-wall lytic activity could be demonstrated. In growing cultures of Bacillus cereus, considerable amounts of hexosamine-containing peptides were released into the medium during the period between the appearance of intracellular spores and free spores. It is suggested that enzyme V may be mainly concerned with the release of free spores from sporangia and enzyme S with the lytic processes which accompany spore germination.", }