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Title: Bacterial spores respond to humidity similarly to hydrogels
Bacterial spores have outstanding properties from the materials science perspective, which allow them to survive extreme environmental conditions. Recent work by [S. G. Harrellsonet al.,Nature619, 500–505 (2023)] studied the mechanical properties ofBacillus subtilisspores and the evolution of these properties with the change of humidity. The experimental measurements were interpreted assuming that the spores behave as water-filled porous solids, subjected to hydration forces. Here, we revisit their experimental data using literature data on vapor sorption on spores and ideas from polymer physics. We demonstrate that upon the change of humidity, the spores behave like rubber with respect to their swelling, elasticity, and relaxation times. This picture is consistent with the knowledge of the materials comprising the bacterial cell walls—cross-linked peptidoglycan. Our results provide an interpretation of the mechanics of bacterial spores and can help in developing synthetic materials mimicking the mechanical properties of the spores.  more » « less
Award ID(s):
1944495
PAR ID:
10508669
Author(s) / Creator(s):
; ;
Publisher / Repository:
PNAS
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
121
Issue:
10
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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