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At least 19 recordsLinked to original sources
PubMed2026

Beyond antibiotics: artificial intelligence-enabled anti-infective ecosystems for next-generation precision therapeutics against antimicrobial resistance.

The rapid global expansion of antimicrobial resistance (AMR) threatens to undermine decades of progress in infectious disease management and highlights the limitations of conventional antibiotic-centered therapeutic strategies. Although emerging technologies-including antimicrobial peptides, bacteriophage therapy, CRISPR-based antimicrobials, microbiome therapeutics, anti-virulence approaches, nanotechnology-enabled drug delivery, and artificial intelligence (AI)-have individually demonstrated considerable promise, they are predominantly being developed as independent interventions rather than as coordinated components of an integrated therapeutic strategy. This Perspective proposes the Intelligent Anti-Infective Ecosystem (IAIE) as a conceptual systems-level framework that computationally integrates multimodal diagnostics, pathogen genomics, microbiome profiling, AI-assisted decision support, programmable precision therapeutics, ecological monitoring, and longitudinal clinical feedback within a continuously learning dynamically optimized workflow. Unlike existing paradigms that primarily optimize individual technologies or therapeutic decisions, IAIE emphasizes closed-loop coordination among complementary antimicrobial approaches to support precision-guided infection management while preserving microbiome integrity and mitigating resistance selection pressure. We further outline the core components, operational principles, translational challenges, and technology readiness of the major therapeutic platforms that could contribute to such an ecosystem, while distinguishing clinically established interventions from emerging experimental strategies. Importantly, IAIE should be interpreted as a prospective conceptual architecture rather than an existing clinical platform. Its proposed clinical value remains to be established through sequential computational, preclinical, and prospective clinical investigations using standardized microbiological, ecological, and patient-centered outcome measures. By framing antimicrobial innovation within an responsive systems perspective, IAIE provides a roadmap for future multidisciplinary research aimed at integrating artificial intelligence and systems microbiology to enable sustainable management of antimicrobial resistance.

Humans↗
PubMed2026

Dynamic balance of CRISPR-Cas immunity and resistance plasmid anti-immunity mediated by a bifunctional protein AcrIE10.

Despite targeting by CRISPR-Cas system, antimicrobial resistance plasmids are prevalent in clinical isolates of carbapenem-resistant Klebsiella pneumoniae which represent a major public health threat. A stable co-existence of plasmids and CRISPR-Cas systems is mediated by anti-CRISPR (Acr) proteins. Here, we report that previously identified AcrIE10 encoded by a resistance plasmid combines two functions: it inhibits CRISPR immunity by directly binding Cas7* subunit through its Acr domain, and acts as an Acr-associated (Aca) protein that self-represses the transcription of Acr locus. AcrIE10 is an example of an Aca protein that utilizes N-terminal ribbon-helix-helix (RHH) domain to specifically recognize the inverted repeat (IR) region in its own promoter. Crucially, a dimerization of AcrIE10 dimers is required for the effective binding to the IR and self-repression, while stoichiometry-dependent interaction with Cas7* facilitates transition to de-repressed state. These findings elucidate molecular mechanisms by which AcrIE10 operates as a dual functionAcr-Aca protein to achieve a delicate balance between host CRISPR-Cas immunity and plasmid anti-defense.

Klebsiella pneumoniae↗
PubMed2024

Non-replicative phage particles delivering CRISPR-Cas9 to target major blaCTX-M variants.

Cluster regularly interspaced short palindromic repeats and CRISPR associated protein 9 (CRISPR-Cas9) is a promising tool for antimicrobial re-sensitization by inactivating antimicrobial resistance (AMR) genes of bacteria. Here, we programmed CRISPR-Cas9 with common spacers to target predominant blaCTX-M variants in group 1 and group 9 and their promoter in an Escherichia coli model. The CRISPR-Cas9 was delivered by non-replicative phagemid particles from a two-step process, including insertion of spacer in CRISPR and construction of phagemid vector. Spacers targeting blaCTX-M promoters and internal sequences of blaCTX-M group 1 (blaCTX-M-15 and -55) and group 9 (blaCTX-M-14, -27, -65, and -90) were cloned into pCRISPR and phagemid pRC319 for spacer evaluation and phagemid particle production. Re-sensitization and plasmid clearance were mediated by the spacers targeting internal sequences of each group, resulting in 3 log10 to 4 log10 reduction of the ratio of resistant cells, but not by those targeting the promoters. The CRISPR-Cas9 delivered by modified ΦRC319 particles were capable of re-sensitizing E. coli K-12 carrying either blaCTX-M group 1 or group 9 in a dose-dependent manner from 0.1 to 100 multiplicity of infection (MOI). In conclusion, CRISPR-Cas9 system programmed with well-designed spacers targeting multiple variants of AMR gene along with a phage-based delivery system could eliminate the widespread blaCTX-M genes for efficacy restoration of available third-generation cephalosporins by reversal of resistance in bacteria.

CRISPR-Cas Systems↗
PubMed2026

CRISPR-Cas and Infectious Diseases: A Decade of Translational Advances in Molecular Biotechnology.

CRISPR-Cas systems have emerged as a versatile tool for diagnosing, treating, and preventing infectious diseases. This review highlights translational advancements in CRISPR-Cas-based applications, concentrating on the past decades in diagnostics, therapeutic genome editing, and vaccine development. The article highlights key platforms like DETECTR and SHERLOCK, which enable rapid, sensitive pathogen detection, and explores CRISPR-Cas9 systems in therapeutic strategies for directly targeting viral genomes and combating antimicrobial resistance. It also examines the role of CRISPR-Cas9 in engineering live-attenuated and personalized neoantigen vaccines. Principal findings demonstrate a clear progression from experimental proof-of-concept to preclinical applications primarily in CRISPR-based diagnostics and the engineering of live-attenuated vaccine candidates, whereas translation in CRISPR-based therapeutics and personalized neoantigen vaccines for infectious diseases remains at earlier, more exploratory stages. CRISPR-based diagnostics have progressed further toward clinical evaluation than therapeutics due to delivery and safety constraints, while personalized neoantigen vaccines are included mainly as an emerging, comparative concept for infectious diseases rather than a mature application. This review uniquely integrates CRISPR-based diagnostics, therapeutics, and vaccine development within a single infectious disease framework, critically assesses their current maturity, and systematically highlights technical, regulatory, and ethical barriers alongside realistic future priorities. The review concludes that while CRISPR-Cas holds transformative potential for infectious disease management, significant challenges in delivery efficiency, off-target effects, and ethical regulation must be addressed to ensure safe and equitable clinical translation.

Humans↗
PubMed2026

Molecular biology and integrated strategies for activating cryptic biosynthetic gene clusters toward next-generation antibiotic discovery.

Antimicrobial resistance (AMR) has been identified as one of the 21st century's severest global public health crises. AMR led to an estimated 4.95 million deaths in 2019 and will claim 10 million lives a year by 2050 in the absence of targeted interventions. During the same period, the number of novel antibiotics discovered has decreased drastically as many researchers are rediscovering known antibiotics, non-model microorganisms are poorly understood or difficult to culture and antibiotic research and development investment has declined drastically. However, high-throughput whole genome sequencing and the subsequent application of bioinformatics in bacterial and fungal genomes have shown that a numerous of cryptic or silent biosynthetic gene clusters (BGCs) remain latent at ambient laboratory conditions since their genes are transcriptionally inactive. Cryptic BGCs represent a vast source of unique secondary metabolites, many of which may yield novel antibacterial, antifungal, anti-cancer and other potentially valuable natural products. This review discusses the biological relevance of cryptic BGCs, the major limiting factors that restricts their activation and novel strategies that have been employed to activate them and exploit their potential to produce novel natural products. The review focuses on biological approaches including CRISPR-Cas mediation for the activation of cryptic BGCs, promoter engineering, pathway refactoring, and heterologous expression; biochemical strategies such as Osman, OsMAC, Precursor Feeding, Chemical Elicitation, Epigenetic Regulation and Co-cultivation and technology-based strategies such as Genome mining, Microfluidic Cultivation systems, High-Throughput Screening, Metabolomics, Molecular Networking and Artificial Intelligence and Machine Learning based prediction of BGCs and their metabolites. The use of multi-omics technologies combined with synthetic biology to achieve better discovery, characterization and large-scale production of novel natural products is also discussed herein. Finally, we will talk about the ecological significance and evolutionary advantage of cryptic BGCs' role in interactions between microorganisms, such as competition, communication, symbiosis and environmental adaptability, so as to provide a useful background for accelerating next-generation antibiotics.

CRISPR-Cas activation↗
PubMed2026

The application of the CRISPR-Cas system in Pseudomonas aeruginosa infections.

Due to the extensive drug resistance of Pseudomonas aeruginosa (P. aeruginosa), it is still a great clinical challenge. The clustered regularly interspaced short palindromic repeats and associated proteins (CRISPR-Cas) system has become a promising strategy against this pathogen. This review critically evaluates the multifaceted applications of CRISPR-Cas technology in P. aeruginosa, including its role in antimicrobial resistance, diagnostics, genome editing, and emerging therapeutic and vaccine strategies. In addition to conducting a comprehensive analysis of various studies, we also compared the performance and limitations of various CRISPR platforms, and discussed the main technologies and transformation obstacles in this field. Finally, we look forward to the direction of applying these experimental tools to clinical research in the future.

Pseudomonas aeruginosa↗
PubMed2026

Endogenous CRISPR-Based Removal of Tetracycline Resistance in Bifidobacterium animalis subsp. lactis Through a Safe-by-Design Approach.

Bifidobacterium animalis subsp. lactis is widely used as a probiotic; however, the presence of the tetracycline resistance gene tetW raises safety and regulatory concerns due to its potential mobility within the gut microbiome. Here, we applied a Safe-by-Design strategy using the endogenous CRISPR-Cas system of B. animalis subsp. lactis BLC01 to inactivate tetW through the introduction of premature stop codons. Whole-genome sequencing confirmed the intended editing and excluded relevant off-target effects. tetW inactivation markedly reduced the tetracycline minimum inhibitory concentration, restoring susceptibility below the tetracycline cut-off value for bifidobacteria (8 μg/mL). Comparative phenotypic analyses demonstrated that the edited strain (BLC01-2F3G10) retained key probiotic traits, including tolerance to acid, bile, and osmotic stress, exopolysaccharide production, aggregation capacity, survival during simulated gastrointestinal digestion and adhesion to intestinal epithelial cells. Importantly, no reversion to tetracycline resistance was observed after prolonged exposure to sub-inhibitory minimal selective antimicrobial concentration, indicating genetic stability of the edited phenotype. Collectively, these findings demonstrate that endogenous CRISPR-based genome editing can be leveraged to selectively remove antimicrobial resistance determinants from probiotic strains while preserving functionality, supporting the development of next-generation probiotics with an improved safety profile and reduced potential for antimicrobial resistance dissemination in the human gut.

Tetracycline Resistance↗
PubMed2026

Precision medicine in combating antimicrobial resistance: A comprehensive review.

Antimicrobial resistance (AMR) represents one of the most pressing threats to global public health, undermining the effectiveness of modern antimicrobial therapy and challenging decades of medical progress. This comprehensive review examines the transition from broad-spectrum empirical therapy toward precision medicine as an integrated framework for improving antimicrobial use and combating AMR. Precision medicine seeks to tailor treatment decisions by combining pathogen-specific genomic and resistance data with relevant host characteristics to optimize therapy while limiting unnecessary antimicrobial exposure and the selective pressures that drive resistance. The review synthesizes advances reported from 2020, highlighting established and emerging approaches including rapid molecular diagnostics, next-generation sequencing, CRISPR-based detection, machine learning (ML)-assisted decision support, precision dosing, and targeted therapeutics such as bacteriophage therapy, antimicrobial peptides, and bacterial proteolysis-targeting chimeras. Rather than functioning as isolated technologies, these approaches achieve their greatest clinical value when integrated within antimicrobial stewardship programs and a One Health framework that recognizes the interconnected human, animal, and environmental drivers of resistance. Despite considerable progress, important challenges remain, including equitable access to advanced technologies, interpretation of increasingly complex datasets, workforce and infrastructure limitations, and evolving regulatory pathways for novel diagnostics and therapeutics. This review concludes that while precision medicine is not a standalone solution, its successful implementation will depend on coordinated integration of diagnostics, host factors, computational tools, pharmacological optimization, and stewardship strategies to improve patient outcomes while preserving the long-term effectiveness of existing antimicrobials.

Antimicrobial resistance↗
PubMed2026

Virus-mediated fate of antimicrobial resistance genes in livestock manure anaerobic digestion.

Antimicrobial resistance (AMR) poses a critical global health challenge, with livestock manure acting as a significant environmental reservoir for antimicrobial resistance genes (ARGs). Anaerobic digestion (AD) is a pivotal process for mitigating ARG dissemination at the livestock-environment-human interface. This study aims to elucidate the global dynamics of ARGs in AD systems, focusing on virus-host interactions and arms race, to identify actionable strategies for AMR control. We analyzed 205 metagenomic (4.5 Tb) and 36 meta-transcriptomic (640 Gb) datasets, including 15 newly generated datasets, revealing that pig manure AD harbors the highest ARG abundance (0.668 ARGs/16S rRNA), while AD systems generally exhibit limited transcriptional activation of ARGs. We constructed a viral dataset for livestock manure AD (GVD_LMAD), comprising 59,316 DNA and 727 RNA viral operational taxonomic units (vOTUs). Virus-host interactions established by CRISPR-Cas spacer, tRNA and homology matches revealed 889 lytic infections of antimicrobial-resistant bacteria (ARB) compared to only 18 ARG transduction events. Further analysis showed that the relative abundance of vOTUs assigned to the reduction role (4.11% ± 3.19%) was substantially higher than that of reproduction (0.72% ± 0.64%) and transduction (0.19% ± 0.30%), demonstrating that, among viral processes, lysis outweighs transduction in contributing to ARG abundance reduction in AD. Furthermore, an antiviral defense system (ADS) catalogue (GADSC_LMAD), derived from 2760 high-quality metagenome-assembled genomes (MAGs) containing 39,307 ADS, with ADS prevalence in ARB (7.8 ± 6.0 per MAG), indicating an intensified virus-host arms race in AD that may shield ARB from phage lysis. The resulting CRISPR-Cas immune network with expressed spacers targets foreign ARG-carrying sequences (primarily plasmids and ICEs), suggesting a mechanism that restricts horizontal gene transfer (HGT) via conjugation and transformation, despite shielding ARB from phage lysis. Collectively, these findings highlight that viral communities significantly contribute to ARG reduction through phage lysis relative to transduction, while the ADS-mediated arms race, despite protecting ARB, constructs a biological firewall that potentially limits HGT of ARGs. This study provides novel insights into virus-host dynamics as a key mechanism for controlling ARG dissemination in AD systems.

Animals↗
PubMed2025

Advancing the fight against tuberculosis: integrating innovation and public health in diagnosis, treatment, vaccine development, and implementation science.

Tuberculosis (TB) remains one of the leading causes of infectious disease mortality worldwide, increasingly complicated by the emergence of drug-resistant strains and limitations in existing diagnostic and therapeutic strategies. Despite decades of global efforts, the disease continues to impose a significant burden, particularly in low- and middle-income countries (LMICs) where health system weaknesses hinder progress. This comprehensive review explores recent advancements in TB diagnostics, antimicrobial resistance (AMR surveillance), treatment strategies, and vaccine development. It critically evaluates cutting-edge technologies including CRISPR-based diagnostics, whole-genome sequencing, and digital adherence tools, alongside therapeutic innovations such as shorter multidrug-resistant TB regimens and host-directed therapies. Special emphasis is placed on the translational gap-highlighting barriers to real-world implementation such as cost, infrastructure, and policy fragmentation. While innovations like the Xpert MTB/RIF Ultra, BPaLM regimen, and next-generation vaccines such as M72/AS01E represent pivotal progress, their deployment remains uneven. Implementation science, cost-effectiveness analyses, and health equity considerations are vital to scaling up these tools. Moreover, the expansion of the TB vaccine pipeline and integration of AI in diagnostics signal a transformative period in TB control. Eliminating TB demands more than biomedical breakthroughs-it requires a unified strategy that aligns innovation with access, equity, and sustainability. By bridging science with implementation, and integrating diagnostics, treatment, and prevention within robust health systems, the global community can accelerate the path toward ending TB.

diagnostic innovation↗
PubMed2026

Whole-genome safety assessment of Loigolactobacillus coryniformis WBB05 and identification of a candidate gene for aerobic reuterin production.

This study reports on the safety profile of Loigolactobacillus coryniformis WBB05 for food industry applications and identifies glycerol-3-phosphate oxidase (GlpO) as a candidate gene associated with aerobic reuterin production. The safety of L. coryniformis WBB05 was evaluated through whole-genome sequencing, phenotypic analysis of haemolytic activity and determination of minimum inhibitory concentrations (MICs) of antibiotics. Comparative genomic analysis was performed to identify candidate genetic determinants for aerobic reuterin production. The draft genome (2.83 Mb, 179 contigs) harboured no known virulence factors, acquired antimicrobial resistance (AMR) genes or biogenic amine biosynthetic genes. Prophage analysis identified only one incomplete prophage region, and four CRISPR-Cas systems (212 spacers) were consistent with phage defence capacity. Secondary metabolite analysis revealed biosynthetic gene clusters encoding a coagulin-like bacteriocin. No β-haemolytic activity was observed. The MICs of all antibiotics tested were below the European Food Safety Authority cut-off values except for kanamycin (128 mg/L), although no acquired AMR genes were detected. Comparative genomic analysis revealed that L. coryniformis WBB05 possesses two putative copies of GlpO, a gene not detected in publicly available genomes of Limosilactobacillus reuteri, which produces reuterin only under anaerobic conditions. These findings support the use of L. coryniformis WBB05 as a safe adjunct culture for dairy applications and highlight GlpO as a candidate determinant of aerobic reuterin production. Further studies comparing GlpO-positive and GlpO-negative strains under aerobic and anaerobic conditions are warranted to confirm the role of GlpO.

Loigolactobacillus coryniformis↗
PubMed2025

Microbe Profile: Streptomyces formicae KY5: an ANT-ibiotic factory.

Streptomyces formicae KY5 was isolated from a Tetraponera penzigi plant-ant nest. It is primarily known for its production of the formicamycins, antibiotics with potent activity against Gram-positive pathogens including methicillin-resistant Staphylococcus aureus, and additionally produces an antifungal compound that inhibits multi-drug-resistant fungal pathogens including Lomentospora prolificans. S. formicae is genetically tractable using CRISPR-Cas9 gene editing, allowing for detailed analysis of the formicamycin biosynthetic gene cluster. AntiSMASH analysis predicts the genome to encode at least 45 secondary metabolite biosynthetic gene clusters, many of which appear to encode novel compounds. Current research efforts are focussing on characterising the regulation of secondary metabolism at a global level in order to switch on pathways that are not typically expressed under standard laboratory conditions with the aim of identifying novel antimicrobials.

Streptomyces↗
PubMed2026

High-efficiency genome-editing, transgene evaluation, and antimicrobial efficacy testing using Citrus medica L. hairy roots.

Huanglongbing (HLB) disease, associated with the fastidious bacterium Candidatus Liberibacter asiaticus (CLas), has a significant impact on citrus production worldwide. Conventional biochemical and genetic evaluation studies to identify potential disease resistance strategies have been mainly hindered due to the inability to culture CLas in a defined medium and the general recalcitrance of Citrus cultivars (grapefruits and oranges) to Agrobacterium-mediated plant transformation. We previously demonstrated the utility of plant hairy roots to co-cultivate CLas. In this study, we developed a hairy root transformation system using citron (Citrus medica L.), which is highly amenable to Rhizobium-mediated hairy root transformation. The explant survival and hairy root transformation efficiencies were up to 100% and 73%, respectively, and transgenic roots can be attained in as little as 30-60 days. We demonstrate the utility of this citron-based hairy root transformation for rapid CRISPR/Cas9-mediated gene editing, transgene evaluation, and antimicrobial efficacy testing. The citron-based hairy root transformation system will significantly help the research community to speed-track the assessment of potential HLB disease resistance strategies.

Citrus↗
PubMed2026

One Plasmid Is All You Need: Genome Editing in Escherichia coli Using Endogenous TnpB and Endogenous Recombination System.

Escherichia coli (E. coli) is a key workhorse of biotechnology. Commonly used CRISPR-Cas9 systems for E. coli genome editing are complex and impose metabolic stress on the host, creating demand for more streamlined strategies. Recent studies identified the IS605 transposon-associated TnpB as a programmable RNA-guided (ωRNA) DNA endonuclease, prompting us to explore whether endogenous TnpB in E. coli (EcoTnpB) could be harnessed for genome editing. Biochemical and cellular analyses demonstrated that EcoTnpB efficiently cleaves both chromosomal and plasmid DNA at custom-specified sites in a TAM-dependent manner. Interestingly, E. coli possesses an endogenous recombination machinery capable of repairing EcoTnpB-induced DNA double-strand breaks (DSBs), challenging the long-held view that bacteria lack efficient homologous recombination systems. Based on these findings, we established a single-plasmid editing system (SPEED) in which genome editing is achieved by simply providing ωRNA and a homologous recombination template. By utilizing endogenous EcoTnpB together with the host HR pathway, this system enabled inducible and seamless genome editing at multiple genomic loci in BL21 (DE3), with editing efficiencies ranging from approximately 29% to 56%. Our results demonstrate for the first time that endogenous TnpB can be harnessed for genome editing and may hold potential for broader applications, such as species-specific antimicrobial development.

Escherichia coli↗
PubMed2025

A genome-wide CRISPRi screen identifies homologous recombination pathway as potential target for broad-spectrum antibiotic adjuvants.

INTRODUCTION: The widespread misuse and overuse of antibiotics have driven the emergence of multidrug-resistant and pan drug-resistant bacteria, constituting a formidable global health threat. Antibiotic adjuvants that potentiate the efficacy of existing antibiotics represent a particularly promising avenue to address this challenge. METHODS: We performed a genome-wide CRISPR interference (CRISPRi) screening to identify potential targets for broad-spectrum antibiotic adjuvants, which highlighted the homologous recombination pathway as a promising candidate. To functionally validate this pathway, we employed three strategies to suppress the expression and function of recA, a key component of homologous recombination, including a CRISPRi system delivered via transconjugation, a RecX-derived peptide (RecX-20) fused to a cell-penetrating motif, and a small-molecule inhibitor cisplatin validated by surface plasmon resonance. RESULTS: Disruption of the homologous recombination pathway not only significantly increased bacterial susceptibility to multiple classes of antibiotics, including quinolones, β-lactams, aminoglycosides, and nitrofurantoin, but also reduced horizontal gene transfer of antibiotic resistance. In addition, recA deficiency resulted in a cascade of physiological disruptions, including membrane damage, efflux pump dysfunction, oxidative stress imbalance and metabolic disruption. All three recA-targeting strategies enhanced the antibacterial activity, with cisplatin exhibiting the most pronounced potentiating effect both in vitro and in vivo. CONCLUSIONS: This study reveals that the homologous recombination pathway, particularly RecA, is a viable target for the development of broad-spectrum antibiotic adjuvant. Our findings provide mechanistic insights and practical strategies to restore the effectiveness of existing antibiotics and address the growing threat of antimicrobial resistance.

Anti-Bacterial Agents↗
PubMed2025

The Arms Race Between Actinobacillus pleuropneumoniae and Its Genetic Environment: A Comprehensive Analysis of Its Defensome and Mobile Genetic Elements.

Actinobacillus pleuropneumoniae is the causative agent of pleuropneumonia in swine, a highly contagious and economically significant disease. The genetic variability of A. pleuropneumoniae complicates disease control efforts, as it enables rapid adaptation to various stressors, including antimicrobial treatments. To better understand the molecular mechanisms underlying this adaptability, we investigated the role of the bacterial defensome and its relationship with mobile genetic elements (MGEs), such as prophages, plasmids, and integrative conjugative elements (ICEs). Using bioinformatic tools, we identified a diverse and rich defensome in A. pleuropneumoniae, with an average of 16 different defense systems per strain. We found that CRISPR-Cas systems, along with other defense mechanisms, are actively involved in restricting the entry of foreign genetic material, playing a crucial role in bacterial adaptation. Additionally, we characterized several novel prophages and examined their distribution across different strains, revealing their potential contribution to the bacterium's evolutionary success. Our findings underscore the complex interplay between the bacterium's defense systems and MGEs, shedding light on how A. pleuropneumoniae maintains genetic diversity while also safeguarding itself against external threats. These insights provide a better understanding of the genetic factors that influence the pathogen's adaptability and highlight potential avenues for more effective disease control strategies.

Actinobacillus pleuropneumoniae↗
PubMed2026

Intra-individual genetic diversity of vaginal Lactobacillus crispatus revealed through citizen science-driven isolation and pangenome analysis.

AIMS: A vaginal microbiome dominated by Lactobacillus crispatus is associated with positive reproductive and sexual health outcomes, yet intra-individual genetic diversity within this species remains largely unexplored. This study characterized inter- and intra-individual genomic variation in L. crispatus strains isolated through a citizen science initiative and assessed implications for multi-strain probiotic development. METHODS AND RESULTS: Fifty-three women participated in this citizen science project. Self-sampling resulted in 48 shotgun metagenomes. Twenty-two participants isolated their own L. crispatus strains using selective enrichment and LAMP-based species confirmation, resulting in 53 whole-genome-sequenced isolates. Lactobacillus crispatus dominated 20 of 48 metagenomes (50.1%-99.6% relative abundance). Pangenome analysis revealed 3456 gene families, of which 43.7% were core and 56.3% accessory. A 14-kb plasmid harbouring a Fic-domain toxin-antitoxin protein, but devoid of antimicrobial resistance genes, was present in 44 of 53 strains. Strains from the same individual clustered closely together yet harboured 1-123 gene differences. Intra-individual variation was observed in the pullulanase type I gene required for glycogen degradation: 40 strains were predicted to grow on glycogen, six showed genetic disruptions with unknown consequences, and seven were predicted to lack this ability entirely. Variation within individuals was also found for bacteriocin classes and CRISPR-Cas genes. CONCLUSIONS: Substantial functional diversity exists within L. crispatus, even among strains from the same individual, supporting the rationale for multi-strain vaginal probiotics. This citizen science approach enabled discovery of host-specific adaptations while ensuring participant ownership of their strains.

Female↗
PubMed2026

Genomic Insights Into Multidrug-Resistant Foodborne Serratia liquefaciens Strains Carrying mcr-9 and Comparative Genomic Analysis of Novel Biosynthetic Gene Clusters.

Serratia liquefaciens is an opportunistic nosocomial pathogen with a wide range of antibiotic resistance patterns. This study reports the characterization of the first mcr-9-positive S. liquefaciens strains, 35E-19E1 and CST-066, isolated from meat products in Japan. The strains were screened for the presence of β-lactamases, plasmid-mediated mobile colistin resistance (mcr) genes, and carbapenemase-encoding genes using PCR. Antimicrobial susceptibility was tested using the broth microdilution method. The strains exhibited multidrug resistance (MDR) phenotypes to third-generation cephalosporins, cephamycin, fosfomycin, and other clinically important antimicrobials. Genomic DNA sequencing showed that the genome sizes of CST-066 and 35E-19E1 are 5,529,704 and 5,261,506 bps, respectively. mcr-9 was identified on a chromosome within a genetic environment that included the two-component system qseBC, which plays a key role in the signaling network that triggers colistin resistance in Enterobacterales. Downstream genome analysis revealed a 1695-bp eptB-like kdo2-lipid phosphoethanolamine transferase, which is involved in intrinsic polymyxin resistance mechanisms in Serratia spp. The strain 35E-19E1 carries five CRISPR-Cas enzymes that are essential for adaptive immunity in bacteria, allowing defense against invading elements. Functional analysis using subsystem technology revealed that both strains possess subsystem features responsible for invasion and adhesion within the host biomes. Genome mining using antiSMASH and BAGL4 revealed various biosynthetic gene clusters, responsible for secondary metabolite synthesis. Notably, we identified novel gene clusters, mainly nonribosomal peptide synthetases, in both the strains, indicating their potential to produce bioactive compounds. Although the presence of mcr-9 in Serratia may not be of clinical significance because of natural resistance of the strain to polymyxins, we shed light on the genomic characteristics of this MDR pathogen and the potential spread of mcr-9 among other bacterial species. The emergence of mcr-9 in drug-resistant S. liquefaciens provides significant insights, underscoring the need for increased surveillance of this pathogen.

biosynthetic gene cluster↗