Genome concentration limits cell growth and modulates proteome composition in Escherichia coli

eLife, Journal Year: 2024, Volume and Issue: 13

Published: May 10, 2024

Defining the cellular factors that drive growth rate and proteome composition is essential for understanding manipulating systems. In bacteria, ribosome concentration known to be a constraining factor of cell rate, while gene usually assumed not limiting. Here, using single-molecule tracking, quantitative single-cell microscopy, modeling, we show genome dilution in Escherichia coli cells arrested DNA replication limits total RNA polymerase activity within physiological sizes across tested nutrient conditions. This rapid-onset limitation on bulk transcription results sub-linear scaling active ribosomes with size sub-exponential growth. Such downstream effects translation are near-immediately detectable nutrient-rich medium, but delayed nutrient-poor conditions, presumably due buffering activities. sequencing tandem-mass-tag mass spectrometry experiments further reveal remodels relative abundance mRNAs proteins at global level. Altogether, our findings indicate chromosome limiting modulator transcriptome E. . Experiments Caulobacter crescentus comparison eukaryotic studies identify broadly conserved concentration-dependent principles expression.

Language: Английский

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Borrelia burgdorferi loses essential genetic elements and cell proliferative potential during stationary phase in culture but not in the tick vector

Journal of Bacteriology, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 14, 2025

ABSTRACT The Lyme disease agent Borrelia burgdorferi is a polyploid bacterium with segmented genome in which both the chromosome and over 20 distinct plasmids are present multiple copies per cell. This pathogen can survive for at least 9 months its tick vector an apparent dormant state between blood meals, without losing cell proliferative capability when re-exposed to nutrients. Cultivated B. cells grown stationary phase or resuspended nutrient-limited media often used study effects of nutrient deprivation. However, thorough assessment spirochete’s ability recover from depletion has been lacking. Our shows that starved cultures rapidly lose ability. Loss genetic elements essential proliferation contributes observed defect phase. gradual decline not perfectly synchronized chromosomes plasmids, generating harbor one more but lack all non-essential plasmids. phenomenon likely well-documented issue plasmid loss during vitro cultivation . In contrast, ticks 14 showed no evidence reduced loss. Beyond their practical implications studying , these findings suggest midgut offers unique environment supports maintenance ’s potential periods fasting. IMPORTANCE causes disease, prevalent tick-borne illness. must long (months year) dormancy meals. Resilience starvation common trait among bacteria. this reveals that, laboratory cultures, poorly endures loses viability. linked required proliferation. These results persistence nature shaped by environmental conditions than innate endure

Language: Английский

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Extrusion-modulated DnaA activity oscillations coordinate DNA replication with biomass growth

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: May 13, 2025

Abstract Robust control of DNA replication is fundamental to bacterial proliferation. In Escherichia coli , initiation thought be regulated by oscillations in DnaA activity, driven DnaA-chromosome interactions that differ among leading models. However, direct evidence linking these has been lacking, and existing models fail explain the observed decoupling from dnaA expression. Here, we establish a link between activity demonstrating robust which peak precisely at across diverse growth conditions genetic perturbations. Notably, persist even when transcription remains constant, suggesting regulatory mechanism modulates independently its Additionally, propose an extrusion model DNA-binding proteins sense biomass-DNA imbalance extrude chromosome trigger replication, overcoming limitations Consistent with this model, perturbation nucleoid-associated protein H-NS timing, supporting mechanistic validity.

Language: Английский

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Borrelia burgdorferi loses essential genetic elements and cell proliferative potential during stationary phase in culture but not in the tick vector.

Published: Oct. 28, 2024

The Lyme disease agent

Language: Английский

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Dynamic cytoplasmic fluidity during morphogenesis in a human fungal pathogen

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 17, 2024

Abstract The molecular crowding of the cytoplasm impacts a range cellular processes. Using fluorescent microrheological probe (GEMs), we observed striking decrease in during yeast to filamentous growth transition human fungal pathogen Candida albicans . This is due ribosome concentration that results part from an inhibition biogenesis, combined with increase cytoplasmic volume; leading dilution major crowder. Moreover, our suggest biogenesis trigger for C. morphogenesis.

Language: Английский

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