Lag Phase Is a Dynamic, Organized, Adaptive, and Evolvable Period That Prepares Bacteria for Cell Division

Journal of Bacteriology, Journal Year: 2019, Volume and Issue: 201(7)

Published: Jan. 15, 2019

Lag is a temporary period of nonreplication seen in bacteria that are introduced to new media. Despite latency being described by Müller 1895, only recently have we gained insights into the cellular processes characterizing lag phase. This review covers literature date on transcriptomic, proteomic, metabolomic, physiological, biochemical, and evolutionary features prokaryotic lag. Though commonly as preparative phase allows harvest nutrients adapt environments, implications recent studies indicate refinement this view well deserved. As shown, dynamic, organized, adaptive, evolvable process protects from threats, promotes reproductive fitness, broadly relevant study bacterial evolution, host-pathogen interactions, antibiotic tolerance, environmental biology, molecular microbiology, food safety.

Language: Английский

---

Molecular Basis of Stationary Phase Survival and Applications

Frontiers in Microbiology, Journal Year: 2017, Volume and Issue: 8

Published: Oct. 16, 2017

Stationary phase is the stage when growth ceases but cells remain metabolically active. Several physical and molecular changes take place during this that make them interesting to explore. The characteristic proteins synthesized in stationary are indispensable as they confer viability bacteria. Detailed knowledge of these genes synthesizing required understand survival such nutrient deprived conditions. promoters, which drive expression genes, called promoters. These promoters exhibit increased activity less or no exponential phase. vectors constructed based on ideal for large scale protein production due absence any external inducers. A number recombinant systems have been developed using This review describes bacteria, involved, their importance, regulation applications.

Language: Английский

---

Hfq CLASH uncovers sRNA-target interaction networks linked to nutrient availability adaptation

eLife, Journal Year: 2020, Volume and Issue: 9

Published: May 1, 2020

By shaping gene expression profiles, small RNAs (sRNAs) enable bacteria to efficiently adapt changes in their environment. To better understand how Escherichia coli acclimatizes nutrient availability, we performed UV cross-linking, ligation and sequencing of hybrids (CLASH) uncover Hfq-associated RNA-RNA interactions at specific growth stages. We demonstrate that Hfq CLASH robustly captures bona fide interactions. identified hundreds novel sRNA base-pairing interactions, including many sRNA-sRNA involving 3'UTR-derived sRNAs. rediscovered known seed sequences. The sRNA-mRNA by have strong potential are highly enriched for complementary sequence motifs, even those supported only a few reads. Yet, steady state levels most mRNA targets were not significantly affected upon over-expression the regulator. Our results reinforce idea reproducibility interaction, potential, is stronger predictor regulatory outcome.

Language: Английский

---

Metabolic fingerprinting of bacteria by fluorescence lifetime imaging microscopy

Scientific Reports, Journal Year: 2017, Volume and Issue: 7(1)

Published: June 12, 2017

Abstract Bacterial populations exhibit a range of metabolic states influenced by their environment, intra- and interspecies interactions. The identification bacterial transitions between them in native environment promises to elucidate community behavior stochastic processes, such as antibiotic resistance acquisition. In this work, we employ two-photon fluorescence lifetime imaging microscopy (FLIM) create fingerprint individual bacteria populations. FLIM autofluorescent reduced nicotinamide adenine dinucleotide (phosphate), NAD(P)H, has been previously exploited for label-free mammalian cells. However, NAD(P)H not established proxy bacteria. Applying the phasor approach, FLIM-phasor maps Escherichia coli , Salmonella enterica serovar Typhimurium Pseudomonas aeruginosa, Bacillus subtilis Staphylococcus epidermidis at single cell population levels. is sensitive environmental conditions exposure growth phase, suggesting that observed shifts are representative changes within approach represents powerful, non-invasive technique study metabolism situ could provide unique insights into behavior, pathology with sub-cellular resolution.

Language: Английский

---

The conserved theme of ribosome hibernation: from bacteria to chloroplasts of plants

Biological Chemistry, Journal Year: 2019, Volume and Issue: 400(7), P. 879 - 893

Published: Jan. 22, 2019

Cells are highly adaptive systems that respond and adapt to changing environmental conditions such as temperature fluctuations or altered nutrient availability. Such acclimation processes involve reprogramming of the cellular gene expression profile, tuning protein synthesis, remodeling metabolic pathways morphological changes cell shape. Nutrient starvation can lead limited energy supply consequently, synthesis is one key steps regulation since translation genetic code into functional polypeptides may consume up 40% a cell's during proliferation. In eukaryotic cells, downregulation stress mainly mediated by modification initiation factors. Prokaryotic cells suppress active formation dimeric so-called 'hibernating' 100S ribosome complexes. transition involves number proteins which found in various forms prokaryotes but also chloroplasts plants. Here, we review current understanding these hibernation factors elaborate conserved principles shared between species.

Language: Английский

---

Acinetobacter baumannii Regulates Its Stress Responses via the BfmRS Two-Component Regulatory System

Journal of Bacteriology, Journal Year: 2021, Volume and Issue: 204(2)

Published: Dec. 6, 2021

Acinetobacter baumannii is a common nosocomial pathogen that utilizes numerous mechanisms to aid its survival in both the environment and host. Coordination of such requires an intricate regulatory network. We report here A. can directly regulate several stress-related pathways via two-component system BfmRS. Similar previous studies, results from transcriptomic analysis showed mutation BfmR response regulator causes dysregulation genes required for oxidative stress response, osmotic misfolded protein/heat shock Csu pilus/fimbria production, capsular polysaccharide biosynthesis. also found BfmRS involved controlling siderophore biosynthesis transport, type IV pili production. provide evidence binds various promoter regions show alone activate transcription some genes. Additionally, we BfmS sensor kinase acts as phosphatase negatively activity. This work highlights importance promoting baumannii. IMPORTANCE has extremely high rates multidrug resistance. organism's ability endure stressful conditions key part spread hospital cause infections. Unlike other members gammaproteobacteria, does not encode homolog RpoS sigma factor coordinate response. Here, demonstrate controls expression multiple resistance Our findings suggest central unique scheme general regulation by

Language: Английский

---

Advances in pulsed electric stimuli as a physical method for treating liquid foods

Physics of Life Reviews, Journal Year: 2023, Volume and Issue: 44, P. 207 - 266

Published: Feb. 2, 2023

Language: Английский

---

Gene expression dynamics in input-responsive engineered living materials programmed for bioproduction

Materials Today Bio, Journal Year: 2023, Volume and Issue: 20, P. 100677 - 100677

Published: May 22, 2023

Engineered living materials (ELMs) fabricated by encapsulating microbes in hydrogels have great potential as bioreactors for sustained bioproduction. While long-term metabolic activity has been demonstrated these systems, the capacity and dynamics of gene expression over time is not well understood. Thus, we investigate microbial ELMs constructed using different hydrogel matrices. Through direct measurements engineered E. coli F127-bisurethane methacrylate (F127-BUM) hydrogels, show that inducible, input-responsive genetic programs can be activated multiple times maintained weeks. Interestingly, encapsulated bacteria sustain inducible almost 10 longer than free-floating, planktonic cells. These exhibit dynamic responsiveness to repeated induction cycles, with up 97% initial retained following a subsequent event. We demonstrate multi-week bioproduction cycling implementing CRISPR transcriptional activation (CRISPRa) regulate enzymes pteridine biosynthesis pathway. from S. cerevisiae bovine serum albumin (BSA) - polyethylene glycol diacrylate (PEGDA) were programmed express two proteins, each under control chemical inducer. observed scheduled switching between betaxanthin pigment molecules proteinase A course 27 days continuous cultivation. Overall, results suggest may general property ELMs. This work establishes approaches dynamic, tailor ELM functions wide range advanced applications.

Language: Английский

---

Hexagonal Boron Nitride Quantum Dots Embedded on Layer-by-Layer Films for Peroxidase-Assisted Colorimetric Detection of β-Galactosidase Producing Pathogens

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 16(20), P. 26870 - 26885

Published: May 13, 2024

Pathogen detection has become a major research area all over the world for water quality surveillance and microbial risk assessment. Therefore, designing simple sensitive kits plays key role in envisaging evaluating of disease outbreaks providing healthcare settings. Herein, we have designed facile low-cost colorimetric sensing strategy selective determination β-galactosidase producing pathogens. The hexagonal boron nitride quantum dots (h-BN QDs) were established as nanozyme that showed prominent peroxidase-like activity, which catalyzes 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation by H2O2. h-BN QDs embedded on layer-by-layer assembled agarose biopolymer. enzyme partially degrades β-1,4 glycosidic bonds polymer, resulting accessibility solid surface. This assay can be conveniently conducted analyzed monitoring blue color formation due to TMB within 30 min. nanocomposite was stable more than 90 days showing after incubating it with Escherichia coli (E. coli). limit calculated 1.8 × 106 1.5 CFU/mL E. Klebsiella pneumonia (K. pneumonia), respectively. Furthermore, this novel approach is an attractive platform successfully applied detect spiked samples other food products good accuracy, indicating its practical applicability pathogens real samples.

Language: Английский

---

Population Ecology-Quantitative Microbial Risk Assessment (QMRA) Model for Antibiotic-Resistant and Susceptible E. coli in Recreational Water

Environmental Science & Technology, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 26, 2025

Understanding and predicting the role of waterborne environments in transmitting antimicrobial-resistant (AMR) infections are critical for public health. A population ecology-quantitative microbial risk assessment (QMRA) model is proposed to evaluate urinary tract infection (UTI) development due recreational exposures Escherichia coli (E. coli) antibiotic-resistant extended-spectrum β-lactamase-producing (ESBL) E. coli. The horizontal gene transfer (HGT) mechanism conjugation other evolutionary factors were modeled separately environment gut. Persistence/dilution dominated HGT environment; however, highly impacted predicted ESBL populations body. Predicted disability life year (DALY) risks from exposure at concentrations consistent with US water criteria less than 10-6 pppy benchmark value but greater susceptible DALY associated a UTI health outcome. However, prevailing dose-response relationship may underestimate if rates vivo approach those reported vitro. sensitivity analysis demonstrated that values, coli/ESBL concentrations, parameters influential on risks. preliminary tool begin expansion QMRA paradigm explore impacts changes AMR assessment.

Language: Английский

---