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Title: Desiccation induces varied responses within a soil bacterial genus
Abstract

Desiccation impacts a suite of physiological processes in microbes by elevating levels of damaging reactive oxygen species and inducing DNA strand breaks. In response to desiccation‐induced stress, microbes have evolved specialized mechanisms to help them survive. Here, we performed a 128‐day lab desiccation experiment on nine strains from three clades of an abundant soil bacterium,Curtobacterium. We sequenced RNA from each strain at three time points to investigate their response.Curtobacteriumwas highly resistant to desiccation, outlasting bothEscherichia coliand a famously DNA damage‐resistant bacterium,Deinococcus radiodurans. However, within the genus, there were also 10‐fold differences in survival rates among strains. Transcriptomic profiling revealed responses shared within the genus including up‐regulation of genes involved in DNA damage repair, osmolyte production, and efflux pumps, but also up‐regulation of pathways and genes unique to the three clades. For example, trehalose synthesis geneotsB, the chaperonegroEL, and the oxygen scavengerkatAwere all found in either one or two clades but not the third. Here, we provide evidence of considerable variation in closely related strains, and further elucidation of the phylogenetic conservation of desiccation tolerance remains an important goal for microbial ecologists.

 
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Award ID(s):
2113004
PAR ID:
10455459
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Environmental Microbiology
Volume:
25
Issue:
12
ISSN:
1462-2912
Format(s):
Medium: X Size: p. 3075-3086
Size(s):
p. 3075-3086
Sponsoring Org:
National Science Foundation
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