Comparison of the properties of Bacillus subtilis spores made in liquid or on agar plates.
OBJECTIVE
To compare the properties of the spores of Bacillus subtilis prepared in liquid and on plates.


RESULTS
The spores of B. subtilis were prepared at 37 degrees C using a nutrient exhaustion medium either in liquid or on agar plates. The levels of core water, dipicolinic acid (DPA) and small, acid-soluble spore proteins (SASP) were essentially identical in spores made in liquid or on plates. Spores prepared in liquid were killed approximately threefold more rapidly at 90 degrees C in water than the spores prepared on plates, and the spores prepared in liquid were more sensitive to nitrous acid and a diluted stable superoxidized water. Spores prepared in liquid also germinated more rapidly with several agents than those prepared on plates. Pellets of spores prepared on plates were darker than spores prepared in liquid, and spores prepared in liquid had more readily extracted coat protein. However, there were no major differences in the relative levels of individual coat proteins or the cross-linking of the coat protein GerQ in the two types of spores, although the inner membrane of spores prepared on plates had a higher ratio of anteiso- to iso-fatty acids.


CONCLUSIONS
The preparation in liquid yielded spores with some different properties than those made on agar plates. Spores made in liquid had lower resistance to heat and several chemicals, and germinated more readily with several agents. There were also differences in the composition of the inner membrane of spores prepared under these two conditions. However, there were no major differences in the levels of DPA, core water, SASP and individual coat proteins or the cross-linking of a coat protein in spores made in liquid and on plates.


CONCLUSIONS
This work demonstrates that the preparation method can affect the resistance and germination properties of bacterial spores, even if an identical medium and temperature are used. Evidence was also obtained consistent with the role of the inner membrane in spore resistance and germination, and that some factor in addition to core water, DPA and SASP content plays a role in spore resistance to wet heat.
Rose
R
R
Department of Molecular, Microbial and Structural Biology, University of Connecticut Health Center, Farmington, CT 06030-3305, USA.
Setlow
B
B
Monroe
A
A
Mallozzi
M
M
Driks
A
A
Setlow
P
P
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001412:Bacillus subtilis / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D001426:Bacterial Proteins / Q000032:analysis; D003470:Culture Media; D004249:DNA Damage; D004269:DNA, Bacterial / Q000187:drug effects; D004202:Disinfectants / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000032:analysis; D006358:Hot Temperature; D009608:Nitrous Acid / Q000494:pharmacology; D010848:Picolinic Acids / Q000032:analysis; D012965:Sodium Chloride; D013171:Spores, Bacterial / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D014867:Water
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D003470:Culture Media; D004269:DNA, Bacterial; D004202:Disinfectants; D004791:Enzyme Inhibitors; D010848:Picolinic Acids; C030069:spore-specific proteins, Bacillus; D014867:Water; D012965:Sodium Chloride; D009608:Nitrous Acid; C004860:dipicolinic acid