Microbiology And Molecular Biology Reviews[JOURNAL]
Sun
200 papers
Resolving spatiotemporal dynamics in bacterial multicellular populations: approaches and challenges.
Espinoza Miranda SS, Abbaszade G, Hess WR … +9 more , Drescher K, Saliba A-E, Zaburdaev V, Chai L, Dreisewerd K, Grünberger A, Westendorf C, Müller S, Mascher T
Microbiol Mol Biol Rev · 2025 Mar · PMID 39853129 · Full text
SUMMARYThe development of multicellularity represents a key evolutionary transition that is crucial for the emergence of complex life forms. Although multicellularity has traditionally been studied in eukaryotes, it orig...
SUMMARYThe development of multicellularity represents a key evolutionary transition that is crucial for the emergence of complex life forms. Although multicellularity has traditionally been studied in eukaryotes, it originates in prokaryotes. Coordinated aggregation of individual cells within the confines of a colony results in emerging, higher-level functions that benefit the population as a whole. During colony differentiation, an almost infinite number of ecological and physiological population-forming forces are at work, creating complex, intricate colony structures with divergent functions. Understanding the assembly and dynamics of such populations requires resolving individual cells or cell groups within such macroscopic structures. Addressing how each cell contributes to the collective action requires pushing the resolution boundaries of key technologies that will be presented in this review. In particular, single-cell techniques provide powerful tools for studying bacterial multicellularity with unprecedented spatial and temporal resolution. These advancements include novel microscopic techniques, mass spectrometry imaging, flow cytometry, spatial transcriptomics, single-bacteria RNA sequencing, and the integration of spatiotemporal transcriptomics with microscopy, alongside advanced microfluidic cultivation systems. This review encourages exploring the synergistic potential of the new technologies in the study of bacterial multicellularity, with a particular focus on individuals in differentiated bacterial biofilms (colonies). It highlights how resolving population structures at the single-cell level and understanding their respective functions can elucidate the overarching functions of bacterial multicellular populations.
Vesicular mechanisms of drug resistance in apicomplexan parasites.
Haldar K, Bhattacharjee S
Microbiol Mol Biol Rev · 2025 Mar · PMID 39853128 · Full text
Vesicular mechanisms of drug resistance are known to exist across prokaryotes and eukaryotes. Vesicles are sacs that form when a lipid bilayer 'bends' to engulf and isolate contents from the cytoplasm or extracellular en...
Vesicular mechanisms of drug resistance are known to exist across prokaryotes and eukaryotes. Vesicles are sacs that form when a lipid bilayer 'bends' to engulf and isolate contents from the cytoplasm or extracellular environment. They have a wide range of functions, including vehicles of communication within and across cells, trafficking of protein intermediates to their rightful organellar destinations, and carriers of substrates destined for autophagy. This review will provide an in-depth understanding of vesicular mechanisms of apicomplexan parasites, Plasmodium and Toxoplasma (that respectively cause malaria and toxoplasmosis). It will integrate mechanistic and evolutionarily insights gained from these and other pathogenic eukaryotes to develop a new model for plasmodial resistance to artemisinins, a class of drugs that have been the backbone of modern campaigns to eliminate malaria worldwide. We also discuss extracellular vesicles that present major vesicular mechanisms of drug resistance in parasite protozoa (that apicomplexans are part of). Finally, we provide a broader context of clinical drug resistance mechanisms of Plasmodium, Toxoplasma, as well as Cryptosporidium and Babesia, that are prominent members of the phyla, causative agents of cryptosporidiosis and babesiosis and significant for human and animal health.
Multiple sclerosis and infection: history, EBV, and the search for mechanism.
SoRelle ED, Luftig MA
Microbiol Mol Biol Rev · 2025 Mar · PMID 39817754 · Full text
SUMMARYInfection has long been hypothesized as the cause of multiple sclerosis (MS), and recent evidence for Epstein-Barr virus (EBV) as the trigger of MS is clear and compelling. This clarity contrasts with yet uncertai...
SUMMARYInfection has long been hypothesized as the cause of multiple sclerosis (MS), and recent evidence for Epstein-Barr virus (EBV) as the trigger of MS is clear and compelling. This clarity contrasts with yet uncertain viral mechanisms and their relation to MS neuroinflammation and demyelination. As long as this disparity persists, it will invigorate virologists, molecular biologists, immunologists, and clinicians to ascertain how EBV potentiates MS onset, and possibly the disease's chronic activity and progression. Such efforts should take advantage of the diverse body of basic and clinical research conducted over nearly two centuries since the first clinical descriptions of MS plaques. Defining the contribution of EBV to the complex and multifactorial pathology of MS will also require suitable experimental models and techniques. Such efforts will broaden our understanding of virus-driven neuroinflammation and specifically inform the development of EBV-targeted therapies for MS management and, ultimately, prevention.
Variable surface antigen expression, virulence, and persistent infection by malaria parasites.
Hadjimichael E, Deitsch KW
Microbiol Mol Biol Rev · 2025 Mar · PMID 39807932 · Full text
SUMMARYThe human malaria parasite is known for its ability to maintain lengthy infections that can extend for over a year. This property is derived from the parasite's capacity to continuously alter the antigens express...
SUMMARYThe human malaria parasite is known for its ability to maintain lengthy infections that can extend for over a year. This property is derived from the parasite's capacity to continuously alter the antigens expressed on the surface of the infected red blood cell, thereby avoiding antibody recognition and immune destruction. The primary target of the immune system is an antigen called PfEMP1 that serves as a cell surface receptor and enables infected cells to adhere to the vascular endothelium and thus avoid filtration by the spleen. The parasite's genome encodes approximately 60 antigenically distinct forms of PfEMP1, each encoded by individual members of the multicopy gene family. This provides the parasite with a repertoire of antigenic types that it systematically cycles through over the course of an infection, thereby maintaining an infection until the repertoire is exhausted. While this model of antigenic variation based on gene switching explains the dynamics of acute infections in individuals with limited anti-malarial immunity, it fails to explain reports of chronic, asymptomatic infections that can last over a decade. Recent field studies have led to a re-evaluation of previous conclusions regarding the prevalence of chronic infections, and the application of new technologies has provided insights into the molecular mechanisms that enable chronic infections and how these processes evolved.
Insights into ecology, pathogenesis, and biofilm formation of from functional genomics.
Willett JLE, Dunny GM
Microbiol Mol Biol Rev · 2025 Mar · PMID 39714182 · Full text
SUMMARY is a significant resident of the gastrointestinal tract of most animals, including humans. Although generally non-pathogenic in healthy hosts, this microbe is adept at the exploitation of compromises in host immu...
SUMMARY is a significant resident of the gastrointestinal tract of most animals, including humans. Although generally non-pathogenic in healthy hosts, this microbe is adept at the exploitation of compromises in host immune functions, resulting in life-threatening opportunistic infections whose treatments are complicated by a high degree of intrinsic and acquired resistance to antimicrobial chemotherapy. Historically, progress in enterococcal research was limited by a lack of experimental models that replicate natural infection pathways and the relevance of studies to the natural biology of the organism. In this review, we summarize the history of enterococcal research during the 20th and early 21st centuries and describe more recent genetic and genomic tools and screens developed to address challenges in the field. We also describe how the results of recent studies reveal the importance of previously uncharacterized enterococcal genes, and we provide examples of interesting determinants that have emerged as important contributors to enterococcal biology. These factors may also serve as targets for future vaccines and chemotherapeutic agents to combat life-threatening hospital infections.
Human coronaviruses: activation and antagonism of innate immune responses.
Tanneti NS, Stillwell HA, Weiss SR
Microbiol Mol Biol Rev · 2025 Mar · PMID 39699237 · Full text
SUMMARYHuman coronaviruses cause a range of respiratory diseases, from the common cold (HCoV-229E, HCoV-NL63, HCoV-OC43, and SARS-CoV-2) to lethal pneumonia (SARS-CoV, SARS-CoV-2, and MERS-CoV). Coronavirus interactions...
SUMMARYHuman coronaviruses cause a range of respiratory diseases, from the common cold (HCoV-229E, HCoV-NL63, HCoV-OC43, and SARS-CoV-2) to lethal pneumonia (SARS-CoV, SARS-CoV-2, and MERS-CoV). Coronavirus interactions with host innate immune antiviral responses are an important determinant of disease outcome. This review compares the host's innate response to different human coronaviruses. Host antiviral defenses discussed in this review include frontline defenses against respiratory viruses in the nasal epithelium, early sensing of viral infection by innate immune effectors, double-stranded RNA and stress-induced antiviral pathways, and viral antagonism of innate immune responses conferred by conserved coronavirus nonstructural proteins and genus-specific accessory proteins. The common cold coronaviruses HCoV-229E and -NL63 induce robust interferon signaling and related innate immune pathways, SARS-CoV and SARS-CoV-2 induce intermediate levels of activation, and MERS-CoV shuts down these pathways almost completely.
STRIPAK, a fundamental signaling hub of eukaryotic development.
Kück U, Pöggeler S
Microbiol Mol Biol Rev · 2024 Dec · PMID 39526753 · Full text
The striatin-interacting phosphatase and kinase (STRIPAK) complex is involved in the regulation of many developmental processes in eukaryotic microorganisms and all animals, including humans. STRIPAK is a component of pr...
The striatin-interacting phosphatase and kinase (STRIPAK) complex is involved in the regulation of many developmental processes in eukaryotic microorganisms and all animals, including humans. STRIPAK is a component of protein phosphatase 2A (PP2A), a highly conserved serine-threonine phosphatase composed of catalytic subunits (PP2Ac), a scaffolding subunit (PP2AA) and various substrate-directing B regulatory subunits. In particular, the B''' regulatory subunit called striatin has evoked major interest over the last 20 years. Studies in fungal systems have contributed substantially to our current knowledge about STRIPAK composition, assembly, and cellular localization, as well as its regulatory role in autophagy and the morphology of fungal development. STRIPAK represents a signaling hub with many kinases and thus integrates upstream and downstream information from many conserved eukaryotic signaling pathways. A profound understanding of STRIPAK's regulatory role in fungi opens the gateway to understanding the multifarious functions carried out by STRIPAK in higher eukaryotes, including its contribution to malignant cell growth.
Threats from the complex: the surge of multidrug resistance and a hotbed for new emerging pathogens.
Gabaldón T
Microbiol Mol Biol Rev · 2024 Dec · PMID 39508581 · Full text
SUMMARY is a common agent of candidiasis that has gained increased attention in recent years, culminating with its recent consideration as a high-priority fungal pathogen by the World Health Organization. Reasons for thi...
SUMMARY is a common agent of candidiasis that has gained increased attention in recent years, culminating with its recent consideration as a high-priority fungal pathogen by the World Health Organization. Reasons for this classification are the recent surge in incidence and the alarmingly growing rates of drug and multidrug resistance. In addition, several closely related species such as and may represent recently emerged opportunistic pathogens originated from environmental niches through interspecies hybridization. Here, I review recent research focused on the potential origin and spread of drug resistance and of emerging species in this complex. I will also discuss open questions regarding the possible implications of human activities in these two epidemiological phenomena.
Bacterial acquisition of host fatty acids has far-reaching implications on virulence.
Waters JK, Eijkelkamp BA
Microbiol Mol Biol Rev · 2024 Dec · PMID 39475267 · Full text
SUMMARYThe lipid homeostasis pathways of bacterial pathogens have been studied comprehensively for their biochemical functionality. However, new and refined technologies have supported the interrogation of bacterial lipi...
SUMMARYThe lipid homeostasis pathways of bacterial pathogens have been studied comprehensively for their biochemical functionality. However, new and refined technologies have supported the interrogation of bacterial lipid and fatty acid homeostasis mechanisms in more complex environments, such as mammalian host niches. In particular, emerging findings on the breadth and depth of host fatty acid uptake have demonstrated their importance beyond merely fatty acid utilization for membrane synthesis, as they can contribute to virulence factor regulation, pathogenesis, and group-based behaviors. Lipid homeostasis is also intertwined with other metabolic and physiological processes in the bacterial cells, which appear to be largely unique per species, but overarching themes can be derived. This review combines the latest biochemical and structural findings and places these in the context of bacterial pathogenesis, thereby shedding light on the far-reaching implications of lipid homeostasis on bacterial success.
Hepatitis B virus entry, assembly, and egress.
Chuang Y-C, Ou J-HJ
Microbiol Mol Biol Rev · 2024 Dec · PMID 39440957 · Full text
SUMMARYHepatitis B virus (HBV) is an important human pathogen that chronically infects approximately 250 million people in the world, resulting in ~1 million deaths annually. This virus is a hepatotropic virus and can ca...
SUMMARYHepatitis B virus (HBV) is an important human pathogen that chronically infects approximately 250 million people in the world, resulting in ~1 million deaths annually. This virus is a hepatotropic virus and can cause severe liver diseases including cirrhosis and hepatocellular carcinoma. The entry of HBV into hepatocytes is initiated by the interaction of its envelope proteins with its receptors. This is followed by the delivery of the viral nucleocapsid to the nucleus for the release of its genomic DNA and the transcription of viral RNAs. The assembly of the viral capsid particles may then take place in the nucleus or the cytoplasm and may involve cellular membranes. This is followed by the egress of the virus from infected cells. In recent years, significant research progresses had been made toward understanding the entry, the assembly, and the egress of HBV particles. In this review, we discuss the molecular pathways of these processes and compare them with those used by hepatitis delta virus and hepatitis C virus , two other hepatotropic viruses that are also enveloped. The understanding of these processes will help us to understand how HBV replicates and causes diseases, which will help to improve the treatments for HBV patients.
Urinary tract infections and catheter-associated urinary tract infections caused by .
El Husseini N, Carter JA, Lee VT
Microbiol Mol Biol Rev · 2024 Dec · PMID 39431861 · Full text
SUMMARYUrinary tract infection (UTI) is one of the most common infections in otherwise healthy individuals. UTI is also common in healthcare settings where patients often require urinary catheters to alleviate urinary re...
SUMMARYUrinary tract infection (UTI) is one of the most common infections in otherwise healthy individuals. UTI is also common in healthcare settings where patients often require urinary catheters to alleviate urinary retention. The placement of a urinary catheter often leads to catheter-associated urinary tract infection (CAUTI) caused by a broad range of opportunistic pathogens, commonly referred to as ESKAPE (, , , , , and ) pathogens. Our understanding of CAUTI is complicated by the differences in pathogens, in initial microbial load, changes that occur due to the duration of catheterization, and the relationship between infection (colonization) and disease symptoms. To advance our understanding of CAUTI, we reviewed UTI and CAUTI caused by which is unique in that it is not commonly found associated with human microbiomes. For this reason, the ability of to cause UTI and CAUTI requires the introduction of the bacteria to the bladder from catheterization. Once in the host, the virulence factors used by in these infections remain an area of ongoing research. In this review, we will discuss studies that focus on UTI and CAUTI to better understand the infection dynamics and outcome in clinical settings, virulence factors associated with isolated from the urinary tract, and animal studies to test which bacterial factors are required for this infection. Understanding how can cause UTI and CAUTI can provide an understanding of how these infections initiate and progress and may provide possible strategies to limit these infections.
Adaptations and metabolic evolution of myzozoan protists across diverse lifestyles and environments.
Waller RF, Carruthers VB
Microbiol Mol Biol Rev · 2024 Dec · PMID 39387588 · Full text
SUMMARYMyzozoans encompass apicomplexans and dinoflagellates that manifest diverse lifestyles in highly varied environments. They show enormous propensity to employ different metabolic programs and exploit different nutr...
SUMMARYMyzozoans encompass apicomplexans and dinoflagellates that manifest diverse lifestyles in highly varied environments. They show enormous propensity to employ different metabolic programs and exploit different nutrient resources and niches, and yet, they share much core biology that underlies this evolutionary success and impact. This review discusses apicomplexan parasites of medical significance and the traits and properties they share with non-pathogenic myzozoans. These include the versatility of myzozoan plastids, which scale from fully photosynthetic organelles to the site of very select key metabolic pathways. Pivotal evolutionary innovations, such as the apical complex, have allowed myzozoans to shift from predatory to parasitic and other symbiotic lifestyles multiple times in both apicomplexan and dinoflagellate branches of the myzozoan evolutionary tree. Such traits, along with shared mechanisms for nutrient acquisition, appear to underpin the prosperity of myzozoans in their varied habitats. Understanding the mechanisms of these shared traits has the potential to spawn new strategic interventions against medically and veterinary relevant parasites within this grouping.
The multifaceted roles of phosphoethanolamine-modified lipopolysaccharides: from stress response and virulence to cationic antimicrobial resistance.
Schumann A, Gaballa A, Wiedmann M
Microbiol Mol Biol Rev · 2024 Dec · PMID 39382292 · Full text
SUMMARYLipopolysaccharides (LPS) are an integral part of the outer membrane of Gram-negative bacteria and play essential structural and functional roles in maintaining membrane integrity as well as in stress response and...
SUMMARYLipopolysaccharides (LPS) are an integral part of the outer membrane of Gram-negative bacteria and play essential structural and functional roles in maintaining membrane integrity as well as in stress response and virulence. LPS comprises a membrane-anchored lipid A group, a sugar-based core region, and an O-antigen formed by repeating oligosaccharide units. 3-Deoxy-D--octulosonic acid-lipid A (Kdo-lipid A) is the minimum LPS component required for bacterial survival. While LPS modifications are not essential, they play multifaceted roles in stress response and host-pathogen interactions. Gram-negative bacteria encode several distinct LPS-modifying phosphoethanolamine transferases (PET) that add phosphoethanolamine (pEtN) to lipid A or the core region of LPS. The genes differ in their genomic locations, regulation mechanisms, and modification targets of the encoded enzyme, consistent with their various roles in different growth niches and under varied stress conditions. The discovery of mobile colistin resistance genes, which represent lipid A-modifying genes that are encoded on mobile elements and associated with resistance to the last-resort antibiotic colistin, has led to substantial interest in PETs and pEtN-modified LPS over the last decade. Here, we will review the current knowledge of the functional diversity of pEtN-based LPS modifications, including possible roles in niche-specific fitness advantages and resistance to host-produced antimicrobial peptides, and discuss how the genetic and structural diversities of PETs may impact their function. An improved understanding of the PET group will further enhance our comprehension of the stress response and virulence of Gram-negative bacteria and help contextualize host-pathogen interactions.
From soil to clinic: current advances in understanding and coccidioidomycosis.
Jackson KM, Teixeira MdM, Barker BM
Microbiol Mol Biol Rev · 2024 Dec · PMID 39365073 · Full text
SUMMARY and are fungal pathogens that cause systemic mycoses and are prevalent in arid regions in the Americas. While mainly occurs in California and Washington, is widely distributed across North and South America. B...
SUMMARY and are fungal pathogens that cause systemic mycoses and are prevalent in arid regions in the Americas. While mainly occurs in California and Washington, is widely distributed across North and South America. Both species induce coccidioidomycosis (San Joaquin Valley fever or, more commonly, Valley fever), with reported cases surging in the United States, notably in California and Arizona. Moreover, cases in Argentina, Brazil, and Mexico are on the rise. Climate change and environmental alterations conducive to spp. proliferation have been recently explored. Diagnostic challenges contribute to delayed treatment initiation, compounded by limited therapeutic options. Although antifungal drugs are often effective treatments, some patients do not respond to current therapies, underscoring the urgent need for a vaccine, particularly for vulnerable populations over 60 years old relocating to endemic areas. Despite recent progress, gaps persist in the understanding of ecology, host immune responses, and vaccine development. This review synthesizes recent research advancements in ecology, genomics, and immune responses, emphasizing ongoing efforts to develop a human vaccine.
: an overlooked cell invader.
Archambaud C, Nunez N, da Silva RAG … +2 more , Kline KA, Serror P
Microbiol Mol Biol Rev · 2024 Sep · PMID 39239986 · Full text
SUMMARY and are human pathobionts that exhibit a dual lifestyle as commensal and pathogenic bacteria. The pathogenic lifestyle is associated with specific conditions involving host susceptibility and intestinal overgrow...
SUMMARY and are human pathobionts that exhibit a dual lifestyle as commensal and pathogenic bacteria. The pathogenic lifestyle is associated with specific conditions involving host susceptibility and intestinal overgrowth or the use of a medical device. Although the virulence of appears to benefit from its antimicrobial resistance, is recognized for its higher pathogenic potential. has long been considered a predominantly extracellular pathogen; it adheres to and is taken up by a wide range of mammalian cells, albeit with less efficiency than classical intracellular enteropathogens. Carbohydrate structures, rather than proteinaceous moieties, are likely to be primarily involved in the adhesion of to epithelial cells. Consistently, few adhesins have been implicated in the adhesion of to epithelial cells. On the host side, very little is known about cognate receptors, except for the role of glycosaminoglycans during macrophage infection. Several lines of evidence indicate that internalization may involve a zipper-like mechanism as well as a macropinocytosis pathway. Conversely, can use several strategies to prevent engulfment in phagocytes. However, the bacterial and host mechanisms underlying cell infection by are still in their infancy. The most recent striking finding is the existence of an intracellular lifestyle where can replicate within a variety of host cells. In this review, we summarize and discuss the current knowledge of -host cell interactions and argue on the need for further mechanistic studies to prevent or reduce infections.
Structural and functional diversity of Resistance-Nodulation-Division (RND) efflux pump transporters with implications for antimicrobial resistance.
Kavanaugh LG, Dey D, Shafer WM … +1 more , Conn GL
Microbiol Mol Biol Rev · 2024 Sep · PMID 39235227 · Full text
SUMMARYThe discovery of bacterial efflux pumps significantly advanced our understanding of how bacteria can resist cytotoxic compounds that they encounter. Within the structurally and functionally distinct families of ef...
SUMMARYThe discovery of bacterial efflux pumps significantly advanced our understanding of how bacteria can resist cytotoxic compounds that they encounter. Within the structurally and functionally distinct families of efflux pumps, those of the Resistance-Nodulation-Division (RND) superfamily are noteworthy for their ability to reduce the intracellular concentration of structurally diverse antimicrobials. RND systems are possessed by many Gram-negative bacteria, including those causing serious human disease, and frequently contribute to resistance to multiple antibiotics. Herein, we review the current literature on the structure-function relationships of representative transporter proteins of tripartite RND efflux pumps of clinically important pathogens. We emphasize their contribution to bacterial resistance to clinically used antibiotics, host defense antimicrobials and other biocides, as well as highlighting structural similarities and differences among efflux transporters that help bacteria survive in the face of antimicrobials. Furthermore, we discuss technical advances that have facilitated and advanced efflux pump research and suggest future areas of investigation that will advance antimicrobial development efforts.
Metabolic homeostasis in fungal infections from the perspective of pathogens, immune cells, and whole-body systems.
Weerasinghe H, Stölting H, Rose AJ … +1 more , Traven A
Microbiol Mol Biol Rev · 2024 Sep · PMID 39230301 · Full text
SUMMARYThe ability to overcome metabolic stress is a major determinant of outcomes during infections. Pathogens face nutrient and oxygen deprivation in host niches and during their encounter with immune cells. Immune cel...
SUMMARYThe ability to overcome metabolic stress is a major determinant of outcomes during infections. Pathogens face nutrient and oxygen deprivation in host niches and during their encounter with immune cells. Immune cells require metabolic adaptations for producing antimicrobial compounds and mounting antifungal inflammation. Infection also triggers systemic changes in organ metabolism and energy expenditure that range from an enhanced metabolism to produce energy for a robust immune response to reduced metabolism as infection progresses, which coincides with immune and organ dysfunction. Competition for energy and nutrients between hosts and pathogens means that successful survival and recovery from an infection require a balance between elimination of the pathogen by the immune systems (resistance), and doing so with minimal damage to host tissues and organs (tolerance). Here, we discuss our current knowledge of pathogen, immune cell and systemic metabolism in fungal infections, and the impact of metabolic disorders, such as obesity and diabetes. We put forward the idea that, while our knowledge of the use of metabolic regulation for fungal proliferation and antifungal immune responses (i.e., resistance) has been growing over the years, we also need to study the metabolic mechanisms that control tolerance of fungal pathogens. A comprehensive understanding of how to balance resistance and tolerance by metabolic interventions may provide insights into therapeutic strategies that could be used adjunctly with antifungal drugs to improve patient outcomes.
Small molecule communication of : the ins and outs of autoinducer and nitric oxide signaling.
Michaelis S, Gomez-Valero L, Chen T … +3 more , Schmid C, Buchrieser C, Hilbi H
Microbiol Mol Biol Rev · 2024 Sep · PMID 39162424 · Full text
SUMMARY is a Gram-negative environmental bacterium, which survives in planktonic form, colonizes biofilms, and infects protozoa. Upon inhalation of -contaminated aerosols, the opportunistic pathogen replicates within and...
SUMMARY is a Gram-negative environmental bacterium, which survives in planktonic form, colonizes biofilms, and infects protozoa. Upon inhalation of -contaminated aerosols, the opportunistic pathogen replicates within and destroys alveolar macrophages, thereby causing a severe pneumonia termed Legionnaires' disease. Gram-negative bacteria employ low molecular weight organic compounds as well as the inorganic gas nitric oxide (NO) for cell-cell communication. produces, secretes, and detects the α-hydroxyketone compound autoinducer-1 (LAI-1, 3-hydroxypentadecane-4-one). LAI-1 is secreted by in outer membrane vesicles and not only promotes communication among bacteria but also triggers responses from eukaryotic cells. detects NO through three different receptors, and signaling through the volatile molecule translates into fluctuations of the intracellular second messenger cyclic-di-guanylate monophosphate. The LAI-1 and NO signaling pathways are linked the pleiotropic transcription factor LvbR. In this review, we summarize current knowledge about inter-bacterial and inter-kingdom signaling through LAI-1 and NO by species.
Microbiology of human spaceflight: microbial responses to mechanical forces that impact health and habitat sustainability.
Nickerson CA, McLean RJC, Barrila J … +7 more , Yang J, Thornhill SG, Banken LL, Porterfield DM, Poste G, Pellis NR, Ott CM
Microbiol Mol Biol Rev · 2024 Sep · PMID 39158275 · Full text
SUMMARYUnderstanding the dynamic adaptive plasticity of microorganisms has been advanced by studying their responses to extreme environments. Spaceflight research platforms provide a unique opportunity to study microbial...
SUMMARYUnderstanding the dynamic adaptive plasticity of microorganisms has been advanced by studying their responses to extreme environments. Spaceflight research platforms provide a unique opportunity to study microbial characteristics in new extreme adaptational modes, including sustained exposure to reduced forces of gravity and associated low fluid shear force conditions. Under these conditions, unexpected microbial responses occur, including alterations in virulence, antibiotic and stress resistance, biofilm formation, metabolism, motility, and gene expression, which are not observed using conventional experimental approaches. Here, we review biological and physical mechanisms that regulate microbial responses to spaceflight and spaceflight analog environments from both the microbe and host-microbe perspective that are relevant to human health and habitat sustainability. We highlight instrumentation and technology used in spaceflight microbiology experiments, their limitations, and advances necessary to enable next-generation research. As spaceflight experiments are relatively rare, we discuss ground-based analogs that mimic aspects of microbial responses to reduced gravity in spaceflight, including those that reduce mechanical forces of fluid flow over cell surfaces which also simulate conditions encountered by microorganisms during their terrestrial lifecycles. As spaceflight mission durations increase with traditional astronauts and commercial space programs send civilian crews with underlying health conditions, microorganisms will continue to play increasingly critical roles in health and habitat sustainability, thus defining a new dimension of occupational health. The ability of microorganisms to adapt, survive, and evolve in the spaceflight environment is important for future human space endeavors and provides opportunities for innovative biological and technological advances to benefit life on Earth.
The polinton-like supergroup of viruses: evolution, molecular biology, and taxonomy.
Koonin EV, Fischer MG, Kuhn JH … +1 more , Krupovic M
Microbiol Mol Biol Rev · 2024 Sep · PMID 39023254 · Full text
SUMMARYPolintons are 15-20 kb-long self-synthesizing transposons that are widespread in eukaryotic, and in particular protist, genomes. Apart from a transposase and a protein-primed DNA polymerase, polintons encode homol...
SUMMARYPolintons are 15-20 kb-long self-synthesizing transposons that are widespread in eukaryotic, and in particular protist, genomes. Apart from a transposase and a protein-primed DNA polymerase, polintons encode homologs of major and minor jelly-roll capsid proteins, DNA-packaging ATPases, and proteases involved in capsid maturation of diverse eukaryotic viruses of kingdom . Given the conservation of these structural and morphogenetic proteins among polintons, these elements are predicted to alternate between transposon and viral lifestyles and, although virions have thus far not been detected, are classified as viruses (class ) in the phylum . Related to polintoviricetes are vertebrate adenovirids; unclassified polinton-like viruses (PLVs) identified in various environments or integrated into diverse protist genomes; virophages (), which are part of tripartite hyperparasitic systems including protist hosts and giant viruses; and capsid-less derivatives, such as cytoplasmic linear DNA plasmids of fungi and transpovirons. Phylogenomic analysis indicates that the polinton-like supergroup of viruses bridges bacterial tectivirids (preplasmiviricot class ) to the phylum that includes large and giant eukaryotic DNA viruses. Comparative structural analysis of proteins encoded by polinton-like viruses led to the discovery of previously undetected functional domains, such as terminal proteins and distinct proteases implicated in DNA polymerase processing, and clarified the evolutionary relationships within . Here, we leverage these insights into the evolution of the polinton-like supergroup to develop an amended megataxonomy that groups , PLVs (new class ''), and virophages (renamed class '') together with (new class '') in a preplasmiviricot subphylum '' sister to a subphylum including ('').
About
- Frequency
- Sun
- Papers found
- 200
- RSS feed
- Subscribe