Abstract:

Principles of cellular resource allocation, established primarily through studies of Escherichia coli since the 1950s, are often likened to 'economic' rules. These principles, involving trade-offs among proteome sectors, allow for predictions about growth rate and lead to growth maximization under specific conditions. However, the applicability of the E. coli framework to other organisms has been unknown. In this study, we reveal that Bacillus subtilis, a model organism, fundamentally diverges from E. coli in terms of growth control. This divergence originates from the decoupling of amino acid flux control from proteome partitioning, achieved through allosteric regulation of amino acid synthesis in B. subtilis. Consequently, growth rate predictions based on proteome partitioning are generally impossible for B. subtilis. We find that in contrast to E. coli, B. subtilis does not prioritize growth maximization, which we demonstrate by accelerating its growth under translational inhibition in an unattainable way in E. coli. This non-growth-maximization strategy enables B. subtilis to recover more rapidly from translational inhibition than E. coli by allostery. Additionally, we observe that the submaximal growth rate of B. subtilis enhances its survival under antibiotic stress. This tradeoff between growth and survival is linked to the pivotal role of GTP in regulating translation, metabolism, and stress response in B. subtilis, contrasting the role of ppGpp in E. coli. Our bioinformatics analysis suggests that GTP-mediated regulation of ribosome synthesis is a common strategy in bacteria. These findings highlight the impact of different regulatory architectures on the evolution of cellular physiology and resource allocation principles.

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When: Feb 6, 2024 05:30 PM Amsterdam, Berlin, Rome, Stockholm, Vienna