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This content will become publicly available on October 3, 2026

Title: Chromosome architecture affects virulence and competitiveness in Agrobacterium tumefaciens C58
Chromosome architecture plays a crucial role in bacterial adaptation, yet its direct impact remains unclear. Different bacterial species and even strains within the same species exhibit diverse chromosomal configurations, including a single circular or linear chromosome, two circular chromosomes, or a circular-linear combination. To investigate how these architectures shape bacterial behavior, we generated near-isogenic strains representing each configuration inAgrobacterium tumefaciensC58, an important soil bacterium widely used for plant genetic transformation. Strains with a single-chromosome architecture, whether linear or circular, exhibited faster growth, enhanced stress tolerance, and greater interstrain competitiveness. In contrast, bipartite chromosome strains showed higher virulence gene expression and enhanced transient plant transformation efficiency, suggesting a pathogenic adaptation. Whole-transcriptome analysis revealed architecture-dependent gene expression patterns, underscoring the profound impact of chromosome organization onAgrobacteriumfitness and virulence. These findings highlight how chromosome structure influences bacterial adaptation and shapes evolutionary trajectories.  more » « less
Award ID(s):
1917138
PAR ID:
10655332
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Sciences
Date Published:
Journal Name:
Science Advances
Volume:
11
Issue:
40
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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