Effect of the osmotic conditions during sporulation on the subsequent resistance of bacterial spores

Abstract : The causes of Bacillus spore resistance remain unclear. Many structures including a highly compact envelope, low hydration of the protoplast, high concentrations of Ca-chelated dipicolinic acid, and the presence of small acid-soluble spore proteins seem to contribute to resistance. To evaluate the role of internal protoplast composition and hydration, spores of Bacillus subtilis were produced at different osmotic pressures corresponding to water activities of 0.993 (standard), 0.970, and 0.950, using the two depressors (glycerol or NaCl). Sporulation of Bacillus subtilis was slower and reduced in quantity when the water activity was low, taking 4, 10, and 17 days for 0.993, 0.970, and 0.950 water activity, respectively. The spores produced at lower water activity were smaller and could germinate on agar medium at lower water activity than on standard spores. They were also more sensitive to heat (97 °C for 5–60 min) than the standard spores but their resistance to high hydrostatic pressure (350 MPa at 40 °C for 20 min to 4 h) was not altered. Our results showed that the water activity of the sporulation medium significantly affects spore properties including size, germination capacity, and resistance to heat but has no role in bacterial spore resistance to high hydrostatic pressure.
Document type :
Journal articles
Complete list of metadatas

https://hal-agrosup-dijon.archives-ouvertes.fr/hal-02291056
Contributor : Administrateur Agrosupdijon <>
Submitted on : Wednesday, September 18, 2019 - 11:19:11 AM
Last modification on : Monday, October 14, 2019 - 2:02:02 PM

Links full text

Identifiers

Citation

Hue Nguyen Thi Minh, Jean-Marie Perrier-Cornet, Patrick Gervais. Effect of the osmotic conditions during sporulation on the subsequent resistance of bacterial spores. Applied Microbiology and Biotechnology, Springer Verlag, 2008, 80 (1), pp.107-114. ⟨10.1007/s00253-008-1519-x⟩. ⟨hal-02291056⟩

Share

Metrics

Record views

36