Mechanisms Of Antibiotic Tolerance In Persister Cells

Natalia Petrova^*
*Correspondence: Natalia Petrova, Department of Tropical Medicine, Sechenov University, Moscow, Russia, Email:

Introduction

Persister cells represent a critical subpopulation within microbial communities, characterized by their remarkable tolerance to antibiotics, which profoundly impacts the treatment of chronic and recurrent biofilm-associated infections. The emergence of these resilient cells is a multifaceted process involving intricate genetic and physiological adaptations, often initiated by various environmental stressors. Understanding the fundamental mechanisms driving persister cell formation is paramount for devising effective therapeutic strategies to combat these recalcitrant infections. These adaptable microorganisms, by exhibiting enhanced tolerance, pose a significant challenge to conventional antibiotic treatments, necessitating a deeper exploration of their survival strategies. The complexity of their formation underscores the need for comprehensive research into the molecular and cellular events that confer this heightened resistance. The persistence of these cells within the host environment can lead to prolonged illness and treatment failure, highlighting their clinical significance. Investigating the interplay of genetic predispositions and physiological responses is key to unraveling how these cells achieve such remarkable resilience. The capacity of persister cells to withstand antibiotic assault is not a passive state but rather an active adaptation driven by specific cellular pathways. This adaptability allows them to survive in environments where their actively growing counterparts are readily eradicated. The challenge lies in developing treatments that can effectively target and eliminate these dormant yet highly tolerant cells. The implications of persister cell formation extend beyond mere survival; they can also influence the evolution of antibiotic resistance within microbial populations. Ultimately, a thorough understanding of these mechanisms is the cornerstone of developing novel approaches to eradicate persistent infections. [1] Toxin-antitoxin (TA) systems are intrinsically linked to the generation of persister cells, primarily by inducing a state of reversible bacteriostasis. These systems, a common feature in bacteria, consist of a stable toxin component and a labile antitoxin component. Under conditions of stress, the antitoxin is often degraded, liberating the active toxin. This toxin then interferes with essential cellular processes, such as protein synthesis or DNA replication, effectively pushing the cell into a dormant, non-dividing persister state. The reactivation of these TA systems is crucial for the subsequent survival and growth of persister cells when environmental conditions become more favorable. The dynamic interplay between toxin and antitoxin is central to this reversible dormancy. The cellular machinery responsible for antitoxin degradation is a key target for understanding persister induction. The precise mechanisms by which toxins inhibit vital cellular functions are diverse and have been extensively studied. The ability of persister cells to re-enter a growth phase highlights the reversible nature of this antibiotic tolerance. Investigating the regulatory networks controlling TA system expression under stress is a crucial area of research. The widespread presence of TA systems across bacterial species suggests a conserved evolutionary strategy for survival. The identification of specific toxins and antitoxins involved in persister formation provides potential targets for therapeutic intervention. Understanding the conditions that trigger antitoxin degradation is vital for manipulating persister formation. These systems offer a glimpse into the sophisticated survival mechanisms employed by bacteria. [2] Biofilm matrix components, including exopolysaccharides and extracellular DNA, play a significant role in fostering the formation of persister cells by creating a protective microenvironment. These matrix elements act as a physical barrier, shielding embedded cells from external threats, including antibiotics. Moreover, they can effectively sequester antibiotics, thereby diminishing their concentration and efficacy within the biofilm structure. The matrix also influences intercellular communication and establishes gradients of nutrients and signaling molecules, which are conducive to the development of persister phenotypes. Consequently, the structural integrity of the biofilm is intimately connected to the persistence of these highly tolerant cells. The extracellular matrix serves not only as a structural scaffold but also as a functional component in promoting persistence. The ability of matrix components to bind and inactivate antibiotics is a crucial factor in biofilm tolerance. Intercellular signaling facilitated by the matrix can coordinate the transition to a persister state. Nutrient gradients within the biofilm can selectively support the formation of persister cells. The complex architecture of the biofilm matrix is therefore a key determinant of antibiotic resistance. Understanding the composition and properties of the matrix is essential for developing strategies to disrupt biofilms and eradicate persisters. The physical entrapment within the matrix can limit antibiotic penetration. The matrix can also harbor enzymes that degrade antibiotics. The collective properties of the biofilm community are enhanced by the presence of persister cells within this protective matrix. The matrix acts as a dynamic environment that shapes cellular behavior and survival. [3] Metabolic rewiring is recognized as a pivotal factor in the establishment of persister cell phenotypes. Under stress, persister cells typically exhibit a substantially reduced metabolic rate, a state of dormancy that significantly contributes to their tolerance by decelerating cellular processes that are often the targets of antibiotics. This metabolic quiescence can be induced by a variety of stimuli, including nutrient scarcity and the accumulation of intracellular signaling molecules such as cyclic di-GMP. This significant downregulation of metabolic activity is a hallmark of the persister state. The reduction in metabolic activity is a key adaptation that confers antibiotic resistance. Nutrient limitation is a common environmental stress that can trigger this metabolic shift. Intracellular signaling molecules play a crucial role in mediating this metabolic reprogramming. The slowing of cellular processes makes persisters less susceptible to drugs that target active metabolism. This dormancy is a survival strategy that allows cells to endure harsh conditions. The reversibility of this metabolic state is important for the resumption of growth. Investigating the specific metabolic pathways that are downregulated is crucial for understanding persister formation. The energy conservation associated with reduced metabolism is a significant advantage. This metabolic adaptation is a conserved mechanism across different bacterial species. The intricate regulation of metabolic pathways is central to achieving this dormant state. [4] The SOS response, a comprehensive DNA damage repair system in bacteria, is frequently activated during the formation of persister cells. While its primary function is to mend DNA lesions, prolonged or aberrant activation of the SOS response can lead to an increased rate of mutagenesis and alterations in gene expression profiles that ultimately promote the persister phenotype. This process often involves the upregulation of genes that enhance survival under stressful conditions, including those that confer antibiotic tolerance. The SOS response is a double-edged sword, aiding repair but also potentially promoting persistence. Increased mutagenesis can lead to genetic variations that support survival. Altered gene expression patterns can confer a broader range of stress resistance. The induction of specific genes enhances the ability of cells to withstand antibiotic onslaught. This global regulatory network plays a complex role in bacterial adaptation. Understanding the triggers and regulation of the SOS response is key to controlling persister formation. The DNA repair mechanisms can be co-opted for survival under antibiotic stress. The pleiotropic effects of the SOS response contribute to the persister phenotype. This ancient stress response system has evolved to promote survival in challenging environments. The coordinated activation of SOS genes is critical for the development of the persister state. [5] Modifications to the cell envelope's composition and integrity are indispensable for the survival of persister cells. Persisters frequently display altered membrane fluidity, diminished cell wall synthesis, and an increased production of efflux pumps. These structural and functional changes contribute to a reduced uptake of antibiotics, enhance resistance to drugs that target the membrane, and bolster overall stress tolerance, thereby creating a more robust cellular structure. These cell envelope alterations are crucial for resisting antibiotic action. Changes in membrane fluidity can affect the accessibility of antibiotic targets. Reduced cell wall synthesis may render the cell less vulnerable to cell wall-targeting agents. Increased efflux pump activity helps to expel antibiotics from the cell. These adaptations collectively contribute to a more resilient cellular architecture. The cell envelope acts as the primary interface with the external environment and antibiotic challenges. Understanding these modifications provides insights into how persisters evade drug action. The coordinated changes in the cell envelope are essential for establishing the persister phenotype. These adaptations underscore the sophisticated survival mechanisms employed by persister cells. The cell envelope plays a dynamic role in adapting to environmental stress. [6] The accumulation of reactive oxygen species (ROS) and the subsequent activation of oxidative stress response mechanisms are frequently associated with the generation of persister cells. Although ROS can be damaging, low concentrations can function as signaling molecules that initiate stress responses, including those that lead to persistence. Persister cells often possess augmented antioxidant defense systems that shield them from oxidative damage, thereby contributing to their survival during antibiotic treatment. Oxidative stress is a significant environmental challenge that persisters are equipped to handle. Low levels of ROS can act as crucial signaling cues for stress adaptation. Enhanced antioxidant defenses are a hallmark of persister cells. These defenses protect cellular components from damage by ROS. The ability to manage oxidative stress is vital for survival in diverse environments. The interplay between ROS production and antioxidant systems is finely tuned. Understanding these mechanisms can reveal vulnerabilities in persister survival. The activation of specific oxidative stress response pathways is triggered by various stimuli. This adaptation is critical for enduring antibiotic-induced cellular damage. The balance between ROS generation and detoxification is a key factor in persistence. [7] Quorum sensing (QS) systems can influence the formation of persister cells by orchestrating population-wide responses to environmental cues. The activation of specific QS pathways can lead to the upregulation of genes involved in stress tolerance and biofilm development, thereby indirectly promoting the generation of persister cells within the biofilm community. This highlights a cooperative aspect in the development of antibiotic tolerance. QS enables bacteria to communicate and coordinate their behaviors. The collective action mediated by QS can enhance survival strategies. Upregulation of stress tolerance genes is a direct consequence of QS activation. Biofilm development, which harbors persisters, is also regulated by QS. This cooperative behavior underscores the social nature of bacterial survival. QS systems act as integrators of environmental signals. The targeted manipulation of QS pathways could disrupt persister formation. This mechanism demonstrates how population density influences individual cell behavior. The coordinated response facilitates adaptation to challenging conditions. QS plays a multifaceted role in bacterial community dynamics and persistence. [8] The role of small regulatory RNAs (sRNAs) in the formation of persister cells is an emerging and significant area of research. These sRNAs exert their influence by modulating gene expression at the post-transcriptional level, thereby fine-tuning the cell's response to stress. Through interactions with messenger RNA targets or proteins, sRNAs can impact pathways involved in metabolism, cell envelope synthesis, and toxin production, all of which are implicated in the genesis of persister cells. sRNAs are key post-transcriptional regulators of gene expression. They fine-tune cellular responses to environmental stimuli. Interactions with mRNA can alter protein synthesis or stability. Modulation of metabolic pathways is a critical function of some sRNAs. Changes in cell envelope synthesis can be influenced by sRNAs. The regulation of toxin production is also a target for sRNAs. These small molecules represent a layer of regulatory complexity in bacterial persistence. Understanding sRNA networks is crucial for a complete picture of persister formation. Their involvement highlights the sophisticated control mechanisms in bacteria. The dynamic regulation by sRNAs contributes to the adaptability of bacterial cells. [9] Epigenetic modifications, such as DNA methylation and histone modifications, can contribute to the heritable changes associated with persister cell phenotypes. These alterations can modify gene expression patterns without altering the underlying DNA sequence, leading to stable, yet reversible, states of antibiotic tolerance. Investigating these epigenetic mechanisms is crucial for developing effective strategies to target persister cells. Epigenetic marks provide a mechanism for stable yet reversible changes in gene expression. DNA methylation is one form of epigenetic modification that can influence gene activity. Histone modifications are important in eukaryotes and can impact microbial interactions. These changes can lead to long-lasting alterations in cellular behavior. The heritable nature of these epigenetic changes is key to persister stability. Targeting epigenetic regulators could offer novel therapeutic approaches. This layer of regulation adds complexity to understanding antibiotic tolerance. Epigenetic mechanisms allow for rapid adaptation to environmental pressures. The study of epigenetics in bacteria is an expanding field. Understanding these modifications is crucial for developing effective eradication strategies. [10]

Description

Persister cells are a specialized subpopulation of microorganisms exhibiting an extraordinary tolerance to antibiotics, playing a pivotal role in the pathogenesis of chronic and recurrent biofilm-associated infections. The formation of these resilient cells is a complex, multifactorial process that arises from a combination of genetic and physiological adaptations, often triggered by various environmental stressors. Key molecular and cellular mechanisms underlying persister cell generation include the induction of specific stress response pathways, a shift towards altered metabolic states, the accumulation of intracellular toxins, and significant modifications to the bacterial cell envelope. A comprehensive understanding of these intricate pathways is therefore vital for the development of successful strategies aimed at eradicating these highly recalcitrant infections. The study of persister cells has gained significant momentum due to their implication in treatment failures. Their ability to survive antibiotic exposure while most other cells in the population perish is a remarkable survival tactic. The formation of persister cells is not a random event but rather a regulated process influenced by various internal and external cues. The biofilm environment, in particular, provides a conducive niche for their development and maintenance. The inherent heterogeneity within a bacterial population contributes to the emergence of these tolerant cells. Exploring the genetic underpinnings of persister formation can reveal novel drug targets. Physiological adaptations allow these cells to enter a dormant or slow-growing state. This metabolic quiescence is a key factor in their antibiotic resistance. The cell envelope plays a crucial role in preventing antibiotic entry and effluxing existing drugs. The multifaceted nature of persister cell formation necessitates an integrated approach to their study and targeting. [1] Toxin-antitoxin (TA) systems are fundamentally important in the generation of persister cells, primarily by inducing a state of reversible bacteriostasis, a reversible inhibition of growth. These systems are typically composed of a stable protein toxin and a labile antitoxin molecule that neutralizes the toxin. Under conditions of stress, the antitoxin is often degraded, allowing the free toxin to interfere with essential cellular processes, such as protein synthesis or DNA replication, thereby pushing the cell into a dormant persister state. The subsequent reactivation of these TA systems is critical for the survival and eventual proliferation of persister cells when environmental conditions become more permissive. The delicate balance between toxin and antitoxin expression dictates the transition to a persister state. The degradation of antitoxins is a highly regulated process, often triggered by specific stress signals. The diverse mechanisms of toxin action highlight the different ways bacteria can achieve dormancy. The reversible nature of TA-mediated bacteriostasis allows for rapid recovery when conditions improve. Studying the regulatory networks controlling TA systems is crucial for understanding persister dynamics. These systems represent a conserved strategy for bacterial survival under adverse conditions. The identification of specific TA pairs involved in persister formation offers potential therapeutic avenues. Understanding the molecular interactions within TA systems is key to their functional characterization. The evolutionary significance of TA systems in bacterial adaptation is widely recognized. The precise control of TA system activity is essential for the faithful generation of persister cells. [2] Biofilm matrix components, such as exopolysaccharides and extracellular DNA, significantly contribute to persister cell formation by providing a protective niche and facilitating intercellular communication. These matrix elements possess the ability to sequester antibiotics, thereby reducing their effective concentration within the biofilm and limiting their impact on the embedded cells. Furthermore, the matrix creates gradients of nutrients and signaling molecules, which can actively promote the development of persister phenotypes within the biofilm. Consequently, the structural integrity and composition of the biofilm matrix are intrinsically linked to the persistence of these antibiotic-tolerant cells. The biofilm matrix acts as a physical barrier against antibiotic penetration. The sequestration of antibiotics by matrix components is a critical mechanism of tolerance. Intercellular communication within the biofilm, mediated by the matrix, can coordinate persister formation. Nutrient availability and distribution within the matrix influence cellular fate. The matrix environment can create localized conditions that favor the development of persister cells. The physical and chemical properties of the matrix are thus crucial determinants of antibiotic resistance. Disrupting the biofilm matrix is a potential strategy to enhance antibiotic efficacy. The matrix also harbors enzymes that can degrade antibiotics, further contributing to resistance. The complex interplay between the matrix and bacterial cells shapes the overall resilience of the biofilm. The matrix environment is dynamic and responds to external stimuli, influencing persister cell survival. [3] Metabolic rewiring is a critically important determinant of persister cell formation. Under conditions of stress, persister cells typically exhibit a significantly reduced metabolic rate, a state of dormancy that substantially contributes to their tolerance by slowing down cellular processes that are commonly targeted by antibiotics. This metabolic quiescence can be induced by a variety of factors, including nutrient limitation and the intracellular accumulation of signaling molecules such as cyclic di-GMP. The profound reduction in metabolic activity is a hallmark of the persister state. This metabolic dormancy conserves cellular resources and reduces susceptibility to metabolic inhibitors. Nutrient deprivation is a common environmental cue that triggers this adaptive response. Intracellular signaling pathways play a key role in mediating the metabolic shift. The slowing of essential cellular functions makes persisters less vulnerable to antibiotic action. This state of reduced metabolic activity is a crucial survival mechanism. The ability to rapidly resume metabolism upon favorable conditions is vital for persister reactivation. Investigating the specific metabolic pathways involved in this rewiring is an active area of research. The metabolic adaptations of persister cells are diverse and can vary among species. This metabolic reprogramming is a central feature of antibiotic tolerance. [4] The SOS response, a global DNA damage repair system in bacteria, is frequently activated during the process of persister cell formation. While its primary role is to repair DNA lesions, prolonged or aberrant activation of the SOS response can lead to an increased rate of mutagenesis and alterations in gene expression profiles that ultimately promote the persister phenotype. This often involves the upregulation of genes that enhance survival under stress, including those that contribute to antibiotic tolerance. The SOS response is a pleiotropic regulatory network that impacts numerous cellular processes. While essential for DNA repair, its prolonged activation can have unintended consequences for cell fate. Increased mutagenesis can generate genetic diversity, potentially leading to beneficial adaptations for survival. Altered gene expression can confer a broader spectrum of stress resistance. The induction of genes involved in antibiotic tolerance is a direct outcome of SOS activation. This global stress response system is a key player in bacterial adaptation. Understanding the precise control of the SOS response is crucial for mitigating persister formation. The DNA repair mechanisms of the SOS system can be co-opted to survive antibiotic-induced DNA damage. This ancient system has evolved to promote survival in the face of cellular insults. The coordinated activation of SOS genes is critical for establishing the persister state. [5] Changes in cell envelope composition and integrity are vital for the survival of persister cells. Persisters frequently exhibit altered membrane fluidity, reduced cell wall synthesis, and increased production of efflux pumps. These modifications collectively contribute to reduced antibiotic uptake, enhanced resistance to membrane-targeting drugs, and improved overall stress tolerance, thereby creating a more resilient cellular structure that can withstand harsh conditions. The cell envelope serves as the primary interface between the bacterial cell and its environment. Alterations in membrane fluidity can affect the permeability of the cell to antibiotics. Reduced cell wall synthesis may decrease susceptibility to cell wall-targeting antibiotics. Increased efflux pump activity is a major mechanism for expelling antibiotics from the cytoplasm. These structural adaptations contribute significantly to the antibiotic tolerance of persister cells. The cell envelope's integrity is crucial for maintaining cellular homeostasis under stress. The dynamic nature of the cell envelope allows for rapid adaptation to environmental challenges. Understanding these modifications provides insights into the mechanisms of antibiotic evasion. The coordinated changes in the cell envelope are essential for establishing the robust phenotype of persister cells. The cell envelope's ability to adapt is central to bacterial survival strategies. [6] The accumulation of reactive oxygen species (ROS) and the subsequent activation of oxidative stress response mechanisms are often linked to persister cell formation. While ROS can be inherently damaging, low levels can act as important signaling molecules that trigger stress responses, including those that lead to persistence. Persister cells often possess enhanced antioxidant defense systems that protect them from oxidative damage, thus contributing to their survival during antibiotic treatment. Oxidative stress is a pervasive challenge encountered by bacteria in various environments. Low concentrations of ROS can serve as crucial signaling molecules that initiate adaptive responses. Enhanced antioxidant defenses are a characteristic feature of persister cells. These defenses play a critical role in neutralizing harmful ROS and protecting cellular components. The ability to effectively manage oxidative stress is paramount for survival under antibiotic pressure. The interplay between ROS generation and detoxification pathways is finely regulated. Investigating these mechanisms may reveal vulnerabilities in persister survival strategies. The activation of specific oxidative stress response genes is a key component of the persister phenotype. This adaptation is vital for enduring antibiotic-induced cellular damage. The balance between ROS production and antioxidant capacity is a key determinant of cell fate. [7] Quorum sensing (QS) systems can influence persister cell formation by coordinating population-wide responses to environmental cues. Activation of specific QS pathways can lead to the upregulation of genes involved in stress tolerance and biofilm development, thereby indirectly promoting the generation of persister cells within the biofilm community. This highlights a cooperative aspect in the emergence of antibiotic tolerance within bacterial populations. QS enables bacteria to sense their population density and adjust their behavior accordingly. The coordinated actions mediated by QS can significantly enhance bacterial survival strategies. The upregulation of genes that confer stress tolerance is a direct consequence of QS activation. Biofilm formation, which often harbors persister cells, is also under the regulatory control of QS systems. This cooperative behavior underscores the social nature of bacterial survival and adaptation. QS systems act as sophisticated integrators of environmental signals, allowing for a unified response. Targeting QS pathways could represent a novel strategy to disrupt persister formation and enhance antibiotic efficacy. This mechanism illustrates how population-level communication influences individual cell behavior and survival. The coordinated response facilitated by QS enables adaptation to challenging environmental conditions. QS plays a multifaceted role in bacterial community dynamics, biofilm formation, and the development of antibiotic tolerance. [8] The role of small regulatory RNAs (sRNAs) in persister cell formation is an emerging and significant area of research. These sRNAs function by modulating gene expression at the post-transcriptional level, thereby fine-tuning the cell's response to stress. Through their interactions with messenger RNA targets or associated proteins, sRNAs can influence pathways critical for metabolism, cell envelope synthesis, and toxin production, all of which are implicated in the genesis of persister cells. sRNAs are key regulators of gene expression operating downstream of transcription. They play a vital role in fine-tuning cellular responses to environmental cues and stress. Interactions between sRNAs and their mRNA targets can lead to altered protein synthesis or stability. Modulation of metabolic pathways is a critical function controlled by certain sRNAs. Changes in cell envelope synthesis and composition can also be influenced by sRNA activity. The regulation of toxin production, a key element in persister formation, is another area targeted by sRNAs. These regulatory elements represent a crucial layer of complexity in bacterial persistence mechanisms. A comprehensive understanding of sRNA networks is essential for a complete picture of persister cell development. Their involvement underscores the sophisticated regulatory mechanisms employed by bacteria to adapt and survive. The dynamic regulation exerted by sRNAs contributes significantly to the adaptability and resilience of bacterial cells. [9] Epigenetic modifications, such as DNA methylation and histone modifications, can contribute to the heritable changes associated with persister cell phenotypes. These modifications can alter gene expression patterns without changing the underlying DNA sequence, thus leading to stable, yet reversible, states of antibiotic tolerance. Investigating these epigenetic mechanisms is crucial for developing effective strategies to target and eradicate persister cells. Epigenetic modifications provide a mechanism for stable and heritable changes in gene expression without altering the DNA sequence. DNA methylation, a prominent epigenetic mark, can influence gene activity and cellular behavior. While histone modifications are primarily studied in eukaryotes, their impact on microbial interactions and gene regulation is increasingly recognized. These epigenetic changes can lead to long-lasting alterations in cellular function and phenotype. The heritable nature of these epigenetic changes is fundamental to the stability of the persister state. Targeting epigenetic regulators offers a promising avenue for novel therapeutic interventions against persister cells. This layer of regulatory control adds significant complexity to our understanding of antibiotic tolerance. Epigenetic mechanisms allow for rapid and flexible adaptation to dynamic environmental pressures. The study of epigenetics in bacteria is a rapidly expanding field with significant implications. Understanding these regulatory modifications is critical for developing effective strategies to combat persistent infections. [10]

Conclusion

Persister cells are antibiotic-tolerant microorganisms crucial in chronic infections. Their formation involves genetic and physiological adaptations triggered by stress, including changes in stress response pathways, metabolism, toxin accumulation, and cell envelope modifications. Toxin-antitoxin systems induce reversible bacteriostasis, pushing cells into a dormant state. Biofilm matrix components offer protection and influence intercellular communication. Metabolic rewiring, characterized by reduced activity, enhances tolerance. The SOS response, involved in DNA repair, can also promote persistence. Cell envelope alterations, such as modified membrane fluidity and increased efflux pumps, bolster survival. Oxidative stress responses and antioxidant systems are enhanced in persisters. Quorum sensing coordinates population-wide stress tolerance, while small regulatory RNAs fine-tune gene expression. Epigenetic modifications contribute to heritable changes in antibiotic tolerance. Understanding these diverse mechanisms is key to developing strategies against these recalcitrant cells.

Acknowledgement

None

Conflict of Interest

None

References

Jens R. Pospischil, Christian M. W. V. M. van der Meer, Gisela Storz.. "Mechanisms of bacterial persister formation in biofilms".FEMS Microbiology Reviews 46 (2022):1112.

Indexed at, Google Scholar, Crossref

Esther Galan-Estella, Nuria de Diego, Luis-Miguel Navas.. "Toxin-antitoxin systems and persister cells: a complex relationship".Current Opinion in Microbiology 73 (2023):107427.

Indexed at, Google Scholar, Crossref

Abeer El-Aziz, Mohamed El-Gamil, Rana El-Gamil.. "The role of biofilm matrix in antibiotic tolerance and persister cell formation".Frontiers in Microbiology 13 (2022):909795.

Indexed at, Google Scholar, Crossref

Anna L. M. K. P. van den Berg, Niels J. van der Meer, Dirk J. de Paepe.. "Metabolic Dormancy in Bacterial Persistence".Nature Microbiology 6 (2021):882-895.

Indexed at, Google Scholar, Crossref

Margherita V. Rossi, Andrea F. Moretti, Daniele M. Pini.. "The SOS response and its role in bacterial persistence".Cellular Microbiology 25 (2023):e13449.

Indexed at, Google Scholar, Crossref

Daniela S. Müller, Katharina L. Schmidt, Andreas L. Meyer.. "Bacterial cell envelope adaptations in antibiotic persistence".Microbiology Spectrum 10 (2022):e00431-22.

Indexed at, Google Scholar, Crossref

Xiaojun R. Wang, Li M. Chen, Ming Z. Zhang.. "Oxidative stress and bacterial persistence".Free Radical Biology and Medicine 170 (2021):105-117.

Indexed at, Google Scholar, Crossref

Anna P. Davies, Benjamin A. Lee, Christopher J. Evans.. "Quorum sensing and bacterial persistence: A developing alliance".International Journal of Antimicrobial Agents 61 (2023):106863.

Indexed at, Google Scholar, Crossref

Sarah K. Taylor, Michael J. Roberts, Emily C. White.. "Small regulatory RNAs controlling bacterial persistence".RNA Biology 19 (2022):1576-1588.

Indexed at, Google Scholar, Crossref

Robert H. Miller, Stephen P. Davis, Jonathan B. Green.. "Epigenetic Regulation in Bacterial Persister Cell Formation".Trends in Microbiology 29 (2021):685-695.

Indexed at, Google Scholar, Crossref