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1.
Cell Host Microbe ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39368473

RESUMEN

Antibiotic use can lead to the expansion of multi-drug-resistant pathobionts within the gut microbiome that can cause life-threatening infections. Selective alternatives to conventional antibiotics are in dire need. Here, we describe a Klebsiella PhageBank for the tailored design of bacteriophage cocktails to treat multi-drug-resistant Klebsiella pneumoniae. Using a transposon library in carbapenem-resistant K. pneumoniae, we identify host factors required for phage infection in major Klebsiella phage families. Leveraging the diversity of the PhageBank, we formulate phage combinations that eliminate K. pneumoniae with minimal phage resistance. Optimized cocktails selectively suppress the burden of K. pneumoniae in the mouse gut and drive the loss of key virulence factors that act as phage receptors. Phage-mediated diversification of bacterial populations in the gut leads to co-evolution of phage variants with higher virulence and broader host range. Altogether, the Klebsiella PhageBank charts a roadmap for phage therapy against a critical multidrug-resistant human pathogen.

2.
J Agric Food Chem ; 72(36): 19931-19939, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39222309

RESUMEN

Glutamate dehydrogenases (GDH) serve as the key regulated enzyme that links protein and carbohydrate metabolism. Combined with motif reassembly and mutation, novel GDHs were designed. Motif reassembly of thermophilic GDH and malate dehydrogenase aims to overcome stability and activity tradeoff in nonaqueous systems. Structural compatibility and dynamic cooperation of the designed AaDHs were studied by molecular dynamics simulation. Furthermore, multipoint mutations improved its catalytic activity for unnatural substrates. Amino acid interaction network analysis indicated that the high density of hydrogen-bonded salt bridges is beneficial to the stability. Finally, the experimental verification determines the kinetics of AaDHs in a nonaqueous system. The activity of Aa05 was increased by 1.78-fold with ionic liquid [EMIM]BF4. This study presents the strategy of a combination of rigid motif assembly and mutations of active sites for robust dehydrogenases with high activity in the nonaqueous system, which overcomes the activity-stability tradeoff effect.


Asunto(s)
Glutamato Deshidrogenasa , Simulación de Dinámica Molecular , Glutamato Deshidrogenasa/química , Glutamato Deshidrogenasa/metabolismo , Glutamato Deshidrogenasa/genética , Cinética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Ingeniería de Proteínas , Estabilidad de Enzimas , Dominio Catalítico , Secuencias de Aminoácidos , Mutación
3.
Microb Pathog ; 196: 106919, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39245422

RESUMEN

A priori, early exposure to a wide range of bacteria, viruses, and parasites appears to fortify and regulate the immune system, potentially reducing the risk of autoimmune diseases. However, improving hygiene conditions in numerous societies has led to a reduction in these microbial exposures, which, according to certain theories, could contribute to an increase in autoimmune diseases. Indeed, molecular mimicry is a key factor triggering immune system reactions; while it seeks pathogens, it can bind to self-molecules, leading to autoimmune diseases associated with microbial infections. On the other hand, a hygiene-based approach aimed at reducing the load of infectious agents through better personal hygiene can be beneficial for such pathologies. This review sheds light on how the evolution of the innate immune system, following the evolution of molecular patterns associated with microbes, contributes to our protection but may also trigger autoimmune diseases linked to microbes. Furthermore, it addresses how hygiene conditions shield us against autoimmune diseases related to microbes but may lead to autoimmune pathologies not associated with microbes.

5.
Viruses ; 16(8)2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39205286

RESUMEN

Endogenous retroviruses (ERVs) are the remnants of retroviral germline infections and are highly abundant in the genomes of vertebrates. At one time considered to be nothing more than inert 'junk' within genomes, ERVs have been tolerated within host genomes over vast timescales, and their study continues to reveal complex co-evolutionary histories within their respective host species. For example, multiple instances have been characterized of ERVs having been 'borrowed' for normal physiology, from single copies to ones involved in various regulatory networks such as innate immunity and during early development. Within the cell, the accessibility of ERVs is normally tightly controlled by epigenetic mechanisms such as DNA methylation or histone modifications. However, these silencing mechanisms of ERVs are reversible, and epigenetic alterations to the chromatin landscape can thus lead to their aberrant expression, as is observed in abnormal cellular environments such as in tumors. In this review, we focus on ERV transcriptional control and draw parallels and distinctions concerning the loss of regulation in disease, as well as their precise regulation in early development.


Asunto(s)
Retrovirus Endógenos , Epigénesis Genética , Retrovirus Endógenos/genética , Humanos , Animales , Metilación de ADN , Regulación Viral de la Expresión Génica , Transcripción Genética , Transcripción Viral/genética , Infecciones por Retroviridae/virología
6.
Int J Mol Sci ; 25(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39201491

RESUMEN

The analysis of protein fold usage, similar to codon usage, offers profound insights into the evolution of biological systems and the origins of modern proteomes. While previous studies have examined fold distribution in modern genomes, our study focuses on the comparative distribution and usage of protein folds in ribosomes across bacteria, archaea, and eukaryotes. We identify the prevalence of certain 'super-ribosome folds,' such as the OB fold in bacteria and the SH3 domain in archaea and eukaryotes. The observed protein fold distribution in the ribosomes announces the future power-law distribution where only a few folds are highly prevalent, and most are rare. Additionally, we highlight the presence of three copies of proto-Rossmann folds in ribosomes across all kingdoms, showing its ancient and fundamental role in ribosomal structure and function. Our study also explores early mechanisms of molecular convergence, where different protein folds bind equivalent ribosomal RNA structures in ribosomes across different kingdoms. This comparative analysis enhances our understanding of ribosomal evolution, particularly the distinct evolutionary paths of the large and small subunits, and underscores the complex interplay between RNA and protein components in the transition from the RNA world to modern cellular life. Transcending the concept of folds also makes it possible to group a large number of ribosomal proteins into five categories of urfolds or metafolds, which could attest to their ancestral character and common origins. This work also demonstrates that the gradual acquisition of extensions by simple but ordered folds constitutes an inexorable evolutionary mechanism. This observation supports the idea that simple but structured ribosomal proteins preceded the development of their disordered extensions.


Asunto(s)
Archaea , Evolución Molecular , Pliegue de Proteína , Proteínas Ribosómicas , Ribosomas , Ribosomas/metabolismo , Proteínas Ribosómicas/metabolismo , Proteínas Ribosómicas/química , Proteínas Ribosómicas/genética , Archaea/metabolismo , Archaea/genética , Eucariontes/metabolismo , Eucariontes/genética , Bacterias/metabolismo , Bacterias/genética , ARN Ribosómico/metabolismo , ARN Ribosómico/genética , ARN Ribosómico/química
7.
J Parasit Dis ; 48(3): 460-473, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39145366

RESUMEN

The redescription of Rostellascaris spinicaudatum has brought to focus Scanning Electron microscopic evidence of evolutionary consequence. The intestinal caeca, ventriculus and ventricular appendix of family Anisakidae; ventriculus and ventricular appendix of family Raphidascaridae; and along with it, post-cloacal collarette of family Physalopteridae in worms recovered from coral-reef associated fish hosts at 'Grande' island, evidently confirmed that the characters of as many as three families were encountered in R. spinicaudatum. The selective adaptation of these specific characters exhibited significant evolutionary trend, and indeed these could radiate connecting link features of Raphidascarididae. Additionally, an inversely bifurcated interlabia on head and pre-cloacal as well as specialized lateral 'sunflower' papillae comprised significant taxonomic information on systematics of ascaridoid (raphidascaridid) nematodes. Interestingly, these worms equipped with remarkably advanced features parasitized primitive host group like, Pisces, in the series of vertebrates, contrary to the characteristics of co-evolution in which parasitizing organism gradually acquired advanced features as it progressed up the ladder of evolution (from Pisces to Mammalia). In the parasitic world, therefore, the worm like Ancylostoma with its occupancy in the highly evolved group i.e. mammals obviously exemplified 'co-evolution', while on the contrary 'Reverse Co-evolution' was the event that was encountered in R. spinicaudatum.

8.
J Membr Biol ; 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150496

RESUMEN

TRPM8 is a non-selective cation channel that is expressed in several tissues and cells and also has a unique property to be activated by low-temperature. In this work, we have analyzed the conservation of amino acids that are present in the lipid-water-interface (LWI) region of TRPM8, the region which experiences a microenvironment near the membrane surface. We demonstrate that the amino acids present in the LWI region are more conserved than the transmembrane or even full-length TRPM8, suggesting strong selection pressure in these residues. TRPM8 also has several conserved cholesterol-binding motifs where cholesterol can bind in different modes and energies. We suggest that mutations and/or physiological conditions can potentially alter these TRPM8-cholesterol complexes and can lead to physiological disorders or even apparently irreversible diseases such as cancer and neurodegeneration.

9.
Mol Ecol ; : e17519, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39192682

RESUMEN

Knowledge of viral biodiversity within insects, particularly within ants, is extremely limited with only a few environmental viruses from invasive ant species identified to date. This study documents and explores the viral communities in ants. We comprehensively profile the metagenomes of a phylogenetically broad group of 35 ant species with varied ecological traits and report the discovery of 3710 novel and unique ant-associated viral genomes. These previously unknown viruses discovered within this study constitute over 95% of all currently described ant viruses, significantly increasing our knowledge of the ant virosphere. The identified RNA and DNA viruses fill gaps in insect-associated viral phylogenies and uncover evolutionary histories characterized by both frequent host switching and co-divergence. Many ants also host diverse bacterial communities, and we discovered that approximately one-third of these new ant-associated viruses are bacteriophages. Two ecological categories, bacterial abundance in the host and habitat degradation are both correlated with ant viral diversity and help to structure viral communities within ants. These data demonstrate that the ant virosphere is remarkably diverse phylogenetically and genomically and provide a substantial foundation for studies in virus ecology and evolution within eukaryotes. We highlight the importance of studying insect-associated viruses in natural ecosystems in order to more thoroughly and effectively understand host-microbe evolutionary dynamics.

10.
Biology (Basel) ; 13(8)2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39194517

RESUMEN

Dinoflagellates and heterotrophic bacteria are two major micro-organism groups within marine ecosystems. Their coexistence has led to a co-evolutionary relationship characterized by intricate interactions that not only alter their individual behaviors but also exert a significant influence on the broader biogeochemical cycles. Our review commenced with an analysis of bacterial populations, both free-living and adherent to dinoflagellate surfaces. Members of Alphaproteobacteria, Gammaproteobacteria, and the Cytophaga-Flavobacterium-Bacteroides group are repeatedly found to be associated with dinoflagellates, with representation by relatively few genera, such as Methylophaga, Marinobacter, and Alteromonas. These bacterial taxa engage with dinoflagellates in a limited capacity, involving nutrient exchange, the secretion of pathogenic substances, or participation in chemical production. Furthermore, the genomic evolution of dinoflagellates has been profoundly impacted by the horizontal gene transfer from bacteria. The integration of bacterial genes into dinoflagellates has been instrumental in defining their biological characteristics and nutritional strategies. This review aims to elucidate the nuanced interactions between dinoflagellates and their associated bacteria, offering a detailed perspective on their complex relationship.

11.
ISME J ; 18(1)2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-39073904

RESUMEN

Antibiotic resistance in plant-associated microbiomes poses significant risks for agricultural ecosystems and human health. Although accumulating evidence suggests a role for plant genotypes in shaping their microbiome, almost nothing is known about how the changes of plant genetic information affect the co-evolved plant microbiome carrying antibiotic resistance genes (ARGs). Here, we selected 16 wheat cultivars and experimentally explored the impact of host genetic variation on phyllosphere microbiome, ARGs, and metabolites. Our results demonstrated that host genetic variation significantly influenced the phyllosphere resistomes. Wheat genotypes exhibiting high phyllosphere ARGs were linked to elevated Pseudomonas populations, along with increased abundances of Pseudomonas aeruginosa biofilm formation genes. Further analysis of 350 Pseudomonas spp. genomes from diverse habitats at a global scale revealed that nearly all strains possess multiple ARGs, virulence factor genes (VFGs), and mobile genetic elements (MGEs) on their genomes, albeit with lower nucleotide diversity compared to other species. These findings suggested that the proliferation of Pseudomonas spp. in the phyllosphere significantly contributed to antibiotic resistance. We further observed direct links between the upregulated leaf metabolite DIMBOA-Glc, Pseudomonas spp., and enrichment of phyllosphere ARGs, which were corroborated by microcosm experiments demonstrating that DIMBOA-Glc significantly enhanced the relative abundance of Pseudomonas spp. Overall, alterations in leaf metabolites resulting from genetic variation throughout plant evolution may drive the development of highly specialized microbial communities capable of enriching phyllosphere ARGs. This study enhances our understanding of how plants actively shape microbial communities and clarifies the impact of host genetic variation on the plant resistomes.


Asunto(s)
Variación Genética , Microbiota , Hojas de la Planta , Pseudomonas , Triticum , Triticum/microbiología , Hojas de la Planta/microbiología , Pseudomonas/genética , Pseudomonas/metabolismo , Factores de Virulencia/genética , Antibacterianos/farmacología , Antibacterianos/metabolismo , Genotipo , Farmacorresistencia Microbiana/genética , Biopelículas/crecimiento & desarrollo , Farmacorresistencia Bacteriana/genética
12.
Infect Genet Evol ; 123: 105620, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38876268

RESUMEN

The Eurasian beaver (Castor fiber), native to Hungary, faced local extinction in 1865 and was successfully reintroduced between mid-1980s and 2008. Despite screening programs focusing on animal health during reintroduction in other countries, information about viruses in the Hungarian beaver population remains limited. Polyomaviruses (PyVs) have been identified in various rodents, and have been detected just recently in beavers by us. In this paper we present the full genome analysis of the first PyV detected in Eurasian beaver. The novel PyV was discovered in the kidney tissues of two specimens. The genome is 5244 bp, and contains four genes. Small T-antigen (STAg) and alternative large T ORF (ALTO) genes are directly fused together forming the middle T-antigen (MTAg). VP3 is absent from the genome. Its large T-antigen (LTAg) coding sequence exhibited over 15% genetic divergence from known PyVs, supporting its classification into a new species within the genus Alphapolyomavirus, suggesting to be named Alphapolyomavirus castoris. Phylogenetic analysis, based on the LTAg gene showed, that the beaver PyV forms a distinct clade with primate PyVs within the genus Alphapolyomavirus, separate from other rodent PyVs. Phylogenetic study of the VP1 gene however showed this virus to belong in a distinct clade with the same primate PyVs, and additionally PyVs from rodents and a myocastor, which suggest host virus co-evolution. The virus detection of the euthanized beavers suggests an apathogenic persistent infections. The aquatic lifestyle of beavers may influence virus transmission, warranting further exploration of undiscovered viruses in beavers.


Asunto(s)
Genoma Viral , Filogenia , Infecciones por Polyomavirus , Poliomavirus , Roedores , Animales , Poliomavirus/genética , Poliomavirus/clasificación , Poliomavirus/aislamiento & purificación , Roedores/virología , Infecciones por Polyomavirus/virología , Infecciones por Polyomavirus/veterinaria , Hungría , Secuenciación Completa del Genoma , Enfermedades de los Roedores/virología , Enfermedades de los Roedores/epidemiología
13.
Front Public Health ; 12: 1375731, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919926

RESUMEN

Introduction: During public health emergencies, online rumors spread widely on social media, causing public information anxiety and emotional fluctuations. Analyzing the co-evolution patterns of online rumor themes and emotions is essential for implementing proactive and precise governance of online rumors during such events. Methods: Rumor texts from mainstream fact-checking platforms during the COVID-19 pandemic were collected and analyzed in phases based on the crisis lifecycle theory. The LDA topic model was applied to analyze the distribution of rumor themes at different stages. The Baidu AI Sentiment Analysis API was used to study the emotional tendencies of rumors at different stages. Line graphs were utilized to analyze the co-evolution characteristics of rumor themes and emotions. Results: During the COVID-19 pandemic, the themes of online rumors can be categorized into five types: epidemic prevention and control, panic-inducing, production and livelihood, virus dissemination, and social figures. These themes exhibited repetition and fluctuation at different stages of the pandemic. The emotions embedded in pandemic-related online rumors evolved with the progression of the pandemic. Panic-inducing rumors co-evolved with negative emotions, while epidemic prevention and control rumors co-evolved with positive emotions. Conclusion: The study results help to understand the public's focus and emotional tendencies at different stages of the COVID-19 pandemic, thereby enabling targeted public opinion guidance and crisis management.


Asunto(s)
COVID-19 , Emociones , Medios de Comunicación Sociales , COVID-19/psicología , COVID-19/epidemiología , Humanos , Pandemias , SARS-CoV-2 , Difusión de la Información , Salud Pública
14.
Insects ; 15(6)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38921172

RESUMEN

Insect pheromones have been intensively studied with respect to their role in insect communication. However, scarce knowledge is available on the impact of pheromones on plant responses, and how these in turn affect herbivorous insects. A previous study showed that exposure of pine (Pinus sylvestris) to the sex pheromones of the pine sawfly Diprion pini results in enhanced defenses against the eggs of this sawfly; the egg survival rate on pheromone-exposed pine needles was lower than that on unexposed pine. The long-lasting common evolutionary history of D. pini and P. sylvestris suggests that D. pini has developed counter-adaptations to these pine responses. Here, we investigated by behavioral assays how D. pini copes with the defenses of pheromone-exposed pine. The sawfly females did not discriminate between the odor of pheromone-exposed and unexposed pine. However, when they had the chance to contact the trees, more unexposed than pheromone-exposed trees received eggs. The exposure of pine to the pheromones did not affect the performance of larvae and their pupation success. Our findings indicate that the effects that responses of pine to D. pini sex pheromones exert on the sawfly eggs and sawfly oviposition behavior do not extend to effects on the larvae.

15.
Front Microbiol ; 15: 1424489, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38939190

RESUMEN

The expansion of betel palm cultivation is driven by rising demand for betel nut, yet this growth is accompanied by challenges such as decreased agricultural biodiversity and the spread of infectious pathogens. Among these, Yellow Leaf Disease (YLD) emerges as a prominent threat to betel palm plantation. Areca Palm Velarivirus 1 (APV1) has been identified as a primary causative agent of YLD, precipitating leaf yellowing, stunted growth, and diminished yield. However, the precise mechanisms underlying APV1-induced damage remain elusive. Our study elucidates that APV1 infiltrates chloroplasts, instigating severe damage and consequential reductions in chlorophyll a/b and carotene levels, alongside notable declines in photosynthetic efficiency. Moreover, APV1 infection exerts broad regulatory effects on gene expression, particularly suppressing key genes implicated in chloroplast function and photosynthesis. These disruptions correlate with growth retardation, yield diminishment, and compromised nut quality. Intriguingly, the paradoxical destruction of the host's photosynthetic machinery by APV1 prompts inquiry into its evolutionary rationale, given the virus's dependence on host resources for replication and proliferation. Our findings reveal that APV1-induced leaf yellowing acts as a beacon for transmission vectors, hinting at a nuanced "host-pathogen-vector co-evolutionary" dynamic.

16.
Plant Sci ; 346: 112165, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38925477

RESUMEN

Agriculture and global food security encounter significant challenges due to viral threats. In the following decades, several molecular studies have focused on discovering biosynthetic pathways of numerous defensive and signaling compounds, as key regulators of plant interactions, either with viruses or their associated vectors. Nevertheless, the complexities of specialized metabolites mediated plant-virus-vector tripartite viewpoint and the identification of their co-evolutionary crossroads toward antiviral defense system, remain elusive. The current study reviews the various roles of plant-specialized metabolites (PSMs) and how plants use these metabolites to defend against viruses. It discusses recent examples of specialized metabolites that have broad-spectrum antiviral properties. Additionally, the study presents the co-evolutionary basis of metabolite-mediated plant-virus-insect interactions as a potential bioinspired approach to combat viral threats. The prospects also show promising metabolic engineering strategies aimed at discovering a wide range of PSMs that are effective in fending off viruses and their related vectors. These advances in understanding the potential role of PSMs in plant-virus interactions not only serve as a cornerstone for developing plant antiviral systems, but also highlight essential principles of biological control.


Asunto(s)
Enfermedades de las Plantas , Virus de Plantas , Plantas , Virus de Plantas/fisiología , Plantas/virología , Plantas/metabolismo , Enfermedades de las Plantas/virología , Animales , Interacciones Huésped-Patógeno , Evolución Biológica
17.
J Transl Med ; 22(1): 559, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38863033

RESUMEN

BACKGROUND: Exploration of adaptive evolutionary changes at the genetic level in vaginal microbial communities during different stages of cervical cancer remains limited. This study aimed to elucidate the mutational profile of the vaginal microbiota throughout the progression of cervical disease and subsequently establish diagnostic models. METHODS: This study utilized a metagenomic dataset consisting of 151 subjects classified into four categories: invasive cervical cancer (CC) (n = 42), cervical intraepithelial neoplasia (CIN) (n = 43), HPV-infected (HPVi) patients without cervical lesions (n = 34), and healthy controls (n = 32). The analysis focused on changes in microbiome abundance and extracted information on genetic variation. Consequently, comprehensive multimodal microbial signatures associated with CC, encompassing taxonomic alterations, mutation signatures, and enriched metabolic functional pathways, were identified. Diagnostic models for predicting CC were established considering gene characteristics based on single nucleotide variants (SNVs). RESULTS: In this study, we screened and analyzed the abundances of 18 key microbial strains during CC progression. Additionally, 71,6358 non-redundant mutations were identified, predominantly consisting of SNVs that were further annotated into 25,773 genes. Altered abundances of SNVs and mutation types were observed across the four groups. Specifically, there were 9847 SNVs in the HPV-infected group and 14,892 in the CC group. Furthermore, two distinct mutation signatures corresponding to the benign and malignant groups were identified. The enriched metabolic pathways showed limited similarity with only two overlapping pathways among the four groups. HPVi patients exhibited active nucleotide biosynthesis, whereas patients with CC demonstrated a significantly higher abundance of signaling and cellular-associated protein families. In contrast, healthy controls showed a distinct enrichment in sugar metabolism. Moreover, biomarkers based on microbial SNV abundance displayed stronger diagnostic capability (cc.AUC = 0.87) than the species-level biomarkers (cc.AUC = 0.78). Ultimately, the integration of multimodal biomarkers demonstrated optimal performance for accurately identifying different cervical statuses (cc.AUC = 0.86), with an acceptable performance (AUC = 0.79) in the external testing set. CONCLUSIONS: The vaginal microbiome exhibits specific SNV evolution in conjunction with the progression of CC, and serves as a specific biomarker for distinguishing between different statuses of cervical disease.


Asunto(s)
Microbiota , Neoplasias del Cuello Uterino , Vagina , Humanos , Femenino , Neoplasias del Cuello Uterino/microbiología , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/genética , Vagina/microbiología , Microbiota/genética , Mutación/genética , Persona de Mediana Edad , Adulto , Polimorfismo de Nucleótido Simple/genética , Estudios de Casos y Controles , Progresión de la Enfermedad
18.
Trends Ecol Evol ; 39(8): 734-744, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38821781

RESUMEN

For five decades, paleontologists, paleobiologists, and ecologists have investigated patterns of punctuated equilibria in biology. Here, we step outside those fields and summarize recent advances in the theory of and evidence for punctuated equilibria, gathered from contemporary observations in geology, molecular biology, genetics, anthropology, and sociotechnology. Taken in the aggregate, these observations lead to a more general theory that we refer to as punctuated evolution. The quality of recent datasets is beginning to illustrate the mechanics of punctuated evolution in a way that can be modeled across a vast range of phenomena, from mass extinctions hundreds of millions of years ago to the possible future ahead in the Anthropocene. We expect the study of punctuated evolution to be applicable beyond biological scenarios.


Asunto(s)
Evolución Biológica , Animales , Modelos Biológicos
19.
J Virol ; 98(6): e0010824, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38742874

RESUMEN

Numerous studies have demonstrated the presence of covert viral infections in insects. These infections can be transmitted in insect populations via two main routes: vertical from parents to offspring, or horizontal between nonrelated individuals. Thirteen covert RNA viruses have been described in the Mediterranean fruit fly (medfly). Some of these viruses are established in different laboratory-reared and wild medfly populations, although variations in the viral repertoire and viral levels have been observed at different time points. To better understand these viral dynamics, we characterized the prevalence and levels of covert RNA viruses in two medfly strains, assessed the route of transmission of these viruses, and explored their distribution in medfly adult tissues. Altogether, our results indicated that the different RNA viruses found in medflies vary in their preferred route of transmission. Two iflaviruses and a narnavirus are predominantly transmitted through vertical transmission via the female, while a nodavirus and a nora virus exhibited a preference for horizontal transmission. Overall, our results give valuable insights into the viral tropism and transmission of RNA viruses in the medfly, contributing to the understanding of viral dynamics in insect populations. IMPORTANCE: The presence of RNA viruses in insects has been extensively covered. However, the study of host-virus interaction has focused on viruses that cause detrimental effects to the host. In this manuscript, we uncovered which tissues are infected with covert RNA viruses in the agricultural pest Ceratitis capitata, and which is the preferred transmission route of these viruses. Our results showed that vertical and horizontal transmission can occur simultaneously, although each virus is transmitted more efficiently following one of these routes. Additionally, our results indicated an association between the tropism of the RNA virus and the preferred route of transmission. Overall, these results set the basis for understanding how viruses are established and maintained in medfly populations.


Asunto(s)
Ceratitis capitata , Virus ARN , Tropismo Viral , Animales , Virus ARN/genética , Virus ARN/fisiología , Femenino , Ceratitis capitata/virología , Masculino , Infecciones por Virus ARN/transmisión , Infecciones por Virus ARN/virología
20.
Arch Microbiol ; 206(6): 281, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38805057

RESUMEN

As a legume crop widely cultured in the world, faba bean (Vicia faba L.) forms root nodules with diverse Rhizobium species in different regions. However, the symbionts associated with this plant in Mexico have not been studied. To investigate the diversity and species/symbiovar affiliations of rhizobia associated with faba bean in Mexico, rhizobia were isolated from this plant grown in two Mexican sites in the present study. Based upon the analysis of recA gene phylogeny, two genotypes were distinguished among a total of 35 isolates, and they were identified as Rhizobium hidalgonense and Rhizobium redzepovicii, respectively, by the whole genomic sequence analysis. Both the species harbored identical nod gene cluster and the same phylogenetic positions of nodC and nifH. So, all of them were identified into the symbiovar viciae. As a minor group, R. hidalgonense was only isolated from slightly acid soil and R. redzepovicii was the dominant group in both the acid and neutral soils. In addition, several genes related to resistance to metals (zinc, copper etc.) and metalloids (arsenic) were detected in genomes of the reference isolates, which might offer them some adaptation benefits. As conclusion, the community composition of faba bean rhizobia in Mexico was different from those reported in other regions. Furthermore, our study identified sv. viciae as the second symbiovar in the species R. redzepovicii. These results added novel evidence about the co-evolution, diversification and biogeographic patterns of rhizobia in association with their host legumes in distinct geographic regions.


Asunto(s)
Filogenia , Rhizobium , Microbiología del Suelo , Simbiosis , Vicia faba , Vicia faba/microbiología , Rhizobium/genética , Rhizobium/aislamiento & purificación , Rhizobium/clasificación , México , Proteínas Bacterianas/genética , Nódulos de las Raíces de las Plantas/microbiología , Suelo/química , N-Acetilglucosaminiltransferasas/genética , Oxidorreductasas/genética , Rec A Recombinasas/genética , Familia de Multigenes
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