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African swine fever virus genotype II was detected in wild boar in Spain in 2025 after >30 years of absence. Whole-genome sequencing and molecular follow-up of 8 representative cases identified a stable 9.8-kb deletion affecting the multigene family in the left variable region, defining an ASFV genotype II variant.
The var multigene family encodes Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), central to host-parasite interactions. Genome structure studies have identified three major groups of var genes by specific upstream sequences (upsA, B, or C). Var with these ups groups have different chromosomal locations, transcriptional directions, and associations with disease severity. Here we explore temporal and spatial diversity of a region of var genes encoding the DBLα domain of PfEMP1 in Africa. By applying a novel ups classification algorithm (cUps) to publicly-available DBLα sequence datasets, we categorised DBLα according to association with the three ups groups, thereby avoiding the need to sequence complete genes. Data from deep sequencing of DBLα types in a local population in northern Ghana surveyed seven times from 2012 to 2017 found variants with rare-to-moderate-to-extreme frequencies, and the common variants were temporally stable in this local endemic area. Furthermore, we observed that every isolate repertoire, whether mono- or multiclonal, comprised DBLα types occurring with these frequency ranges implying a common genome structure. When comparing African countries of Ghana, Gabon, Malawi, and Uganda, we report that some DBLα types were consistently found at high frequencies in multiple African countries while others were common only at the country level. The implication of these local and pan-Africa population patterns is discussed in terms of advantage to the parasite with regards to within-host adaptation and resilience to malaria control.
Many bacterial pathogens depend on a type II secretion (T2S) system to secrete virulence factors from the periplasm into the extracellular milieu. T2S systems consist of an outer membrane secretin channel, a periplasmic pseudopilus and an inner membrane-associated assembly platform including a cytoplasmic ATPase. The components of T2S systems are often conserved in different bacterial species, however, the architecture of the assembly platform is largely unknown. Here, we analysed predicted assembly platform components of the Xps-T2S system from the plant-pathogenic bacterium Xanthomonas euvesicatoria. To facilitate these studies, we generated a modular xps-T2S gene cluster by Golden Gate assembly of single promoter and gene fragments. The modular design allowed the efficient deletion and replacement of T2S genes and the insertion of reporter fusions. Mutant approaches as well as interaction and crosslinking studies showed that the predicted assembly platform components XpsC, XpsL and XpsM form a trimeric complex which is essential for T2S and associates with the cytoplasmic ATPase XpsE and the secretin XpsD. Structural modeling revealed a similar trimeric architecture of XpsCLM homologs from Pseudomonas, Vibrio and Klebsiella species, despite overall low amino acid sequence similarities. In X. euvesicatoria, crosslinking and fluorescence microscopy studies showed that the formation of the XpsCLM complex is independent of the secretin and vice versa, suggesting that the assembly of the T2S system is a dynamic process which involves the association of preformed subcomplexes.
Symbiont-mediated male killing (MK) is a mechanism that selectively eliminates male offspring, often by disrupting sex-specific developmental processes. In Drosophila melanogaster, the WO-mediated killing gene wmk from Wolbachia prophage WO transgenically reproduces the MK phenotype, yet how the gene evolves and functions across diverse Wolbachia has not been systematically investigated. We analyzed 32 Wolbachia genomes available in the NCBI database to study wmk homologs across different arthropod hosts, reproductive parasitism functions, and Wolbachia supergroups. First, we report at least five distinct wmk phylogenetic clusters (Types I to V), often organized in multigenic dyads or triads. Second, among MK Wolbachia, there is a significantly higher number of wmk genes and diversity in Lepidoptera strains than in Drosophila strains, which exclusively harbor wmk Types I and III. Third, there are three patterns of wmk sequence and genomic organizational changes in Drosophila MK strains that associate with different evolutionary trajectories underpinning the MK phenotype. Fourth, single and combinatory transgenic expression of Types I and III in D. melanogaster uncovers male-biased lethality associated with Type I; however, dual expression of the Types together elicits a major reduction in offspring number. Fifth, wmk genes have low expression level across D. melanogaster developmental stages relative to the cifA and cifB genes, which could explain why cytoplasmic incompatibility is expressed in this system. These findings establish a complex and phylogenetically informed genetic basis of wmk-induced lethality, highlighting the role of gene copy number and expression, wmk Types, and host background in shaping the phenotype.
The ability of myeloid cells to recognize and differentiate endogenous or exogenous ligands rely on the presence of different transmembrane protein receptors. C-type lectin receptors (CLRs), defined by the presence of a conserved structural motif called C-type lectin-like domain (CTLD), are a crucial family of receptors involved in this process, being able to recognize a diverse range of ligands from glycans to proteins or lipids and capable of initiating an immune response. The Dectin-1 and Dectin-2 clusters involve two groups of CLRs, with genes genomically linked within the natural killer cluster of genes in both humans and mice, and all characterized by the presence of a single extracellular CTLD. Fundamental immune cell functions such as antimicrobial effector mechanisms as well as internalization and presentation of antigens are induced and/or regulated through activatory, or inhibitory signalling pathways triggered by these receptors after ligand binding. In this review, we will discuss the most recent concepts regarding expression, ligands, signaling pathways and functions of each member of the Dectin clusters of CLRs, highlighting the importance and diversity of their functions.
Salmonella enterica serovar Typhi (S. Typhi) encodes 14 fimbrial gene clusters, including the mannose-binding type 1 fimbriae known as Fim. Type 1 fimbriae have been implicated in biofilm formation and adhesion to host cells in Salmonella. However, their regulation in S. Typhi remains largely unknown. To identify genes affecting the regulation of fim in S. Typhi, we employed both a targeted and a genome-wide transposon-based screening approach. Overall, we identified 18 potential regulators of fim expression: 10 activators and 8 repressors. Two genes involved in the electron transport chain, yqiC and ndh, which encode the type II NADH dehydrogenase NDH-2, were identified. Both YqiC and NDH-2 contribute to the production of reactive oxygen species, prompting an investigation into the roles of oxidative stress response regulators OxyR and SoxR. We found that only OxyR regulates fim expression, which was specific to S. Typhi. OxyR acts by directly binding to the fimA promoter region. This study paves the way for future development of anti-adhesion strategies through the identification of 14 novel regulators for the most prominent fimbriae of S. Typhi.IMPORTANCEAdhesion mediated by fimbriae is one of the critical steps in the infection process. Therefore, it is essential to better understand the regulation of type 1 fimbriae (fim) in the human-specific pathogen Salmonella enterica serovar Typhi, the etiologic agent of typhoid fever. In this study, we identified 18 distinct mutants with altered regulation of fim. Furthermore, we confirmed that the DNA-binding protein OxyR directly regulates fim expression. Importantly, we also demonstrated regulatory differences in fim expression between S. Typhi and S. Typhimurium, as six of the genes identified altering fim expression in S. Typhi either did not affect fim expression in S. Typhimurium or had the contrary effect. This highlights fundamental differences between these serovars and emphasizes the need to investigate and compare aspects of gene regulation in S. Typhi.
The Class II myosin light chain (myl) genes in Chinese perch (Siniperca chuatsi) have not yet been systematically characterised, and relationships with muscle fibre specification, development, and injury-associated remodelling remain unclear. In this study, fast and slow muscle fibres were initially distinguished using myofibrillar ATPase histochemistry. Subsequently, genome-wide mining identified 16 Class II myl genes, comprising eight essential and eight regulatory light-chain subunits. Their conserved-domain features, chromosomal distribution, phylogenetic relationships and expression profiles were analysed. Transcriptomic profiling showed that summed myl transcript abundance was higher in fast muscle than in slow muscle, accounting for 67.2% of the pooled myl transcript pool across the two muscle types (paired t-test, raw P = 0.036). mylpfa, myl1 and mylz3 were the major fast-muscle-associated genes, whereas myl10, myl2b and myl13 were preferentially expressed in slow muscle at the transcript level. These patterns support these genes as candidate fibre-type-associated expression markers. Developmental profiling identified stage-associated myl expression patterns, including a possible expression shift between mylpfb and mylpfa. In the descriptive injury-repair time course (d0-d7), FPKM profiles indicated that fast-muscle-associated genes (mylpfa, mylz3 and myl1) were lower at d1 and recovered by d3, whereas several slow-muscle-associated genes showed biphasic transcript-level increases. The slow-muscle-associated RLC gene mylpfb showed a delayed expression peak at d7. Notably, the embryonic isoform myl6l showed a modest increase from approximately 2 FPKM at d0 to 4-5 FPKM after injury, suggesting a possible injury-associated expression pattern that requires further validation. Together, these findings provide a genome-wide description of the Chinese perch myl gene family and identify candidate fibre-type-associated genes and descriptive injury-associated isoform expression patterns.
Four marine bacterial strains of the genus Vibrio, designated WJH972T, RC27, FJH11T, and HA2012T, were isolated from coastal habitats in China. Phenotypic and physiological characterization showed that all four strains are Gram-stain-negative, facultatively anaerobic, short rod-shaped cells, and motile. The 16S rRNA gene sequence similarities between the isolates and their closest relatives were 96.5% - 98.2%, above the genus-level threshold but below the species delineation cutoff. Genomic analysis revealed that strains WJH972T and RC27 shared an average nucleotide identity (ANI) of 98.7% and a digital DNA-DNA hybridization (dDDH) value of 89.9%, confirming their conspecificity. In contrast, the ANI and dDDH values between the four strains and known Vibrio species ranged from 78.6% to 85.8% and from 13.7% to 59.3%, respectively, both falling below the thresholds for species delineation. The biosynthetic gene clusters support bacterial potentials for stress tolerance and antibiotic synthesis, consistent with strain FJH11T's resistance to all 20 antibiotics and other strains' sensitivity to chloramphenicol and penicillin. Based on these polyphasic taxonomic evidence above, three novel species are thus proposed: Vibrio limimangrovi sp. nov. (type strain FJH11T), Vibrio phycocola sp. nov. (type strain WJH972T), and Vibrio sediminis sp. nov. (type strain HA2012T). This study provides novel insights into the systematics, metabolic diversity, antibiotic resistance, and ecological distribution of the genus Vibrio.
Grapevine cultivars vary widely in monoterpenoid content, yet the genetic and regulatory mechanisms underlying this variation remain poorly characterized beyond highly aromatic Muscat types. We profiled free volatiles and monoterpenoid glycosides in a Riesling × Cabernet Sauvignon F1 mapping population, revealing extensive variation and transgressive segregation consistent with multigenic control. QTL mapping identified 70 significant loci associated with 48 volatile compounds and monoterpene glycosides, including two major QTLs explaining 33.6% and 33.4% of phenotypic variance in (3S)-linalool accumulation. Integration of haplotype-resolved transcriptomics with metabolite data, enabled by a chromosome-scale diploid Riesling genome assembly, resolved a (3S)-linalool/nerolidol synthase cluster on chromosome 10 and identified VviTPS54 as the strongest candidate underlying linalool variation. VviTPS54 exhibited haplotype-specific expression strongly correlated with (3S)-linalool accumulation across genotypes, while no QTL was detected at the 1-deoxy-D-xylulose-5-phosphate synthase 1 (VviDXS1) locus previously identified in Muscat cultivars. In addition, VviDXS1 expression was not correlated with terpene levels, indicating that regulatory variation within terpene synthase clusters, rather than methylerythritol phosphate (MEP) pathway flux, drives monoterpenoid composition in this population. These results establish regulatory variation of terpene synthases as a key mechanism underlying monoterpenoid diversity in grapevine and demonstrate that resolving such variation requires haplotype-phased genome assemblies coupled with haplotype-resolved transcriptomics to detect allele-specific expression differences at complex, heterozygous loci.
SUMMARY: CatsCradle is an R package for single-cell analysis that exploits the duality between cells and the genes they express. Our package provides tools to cluster genes, visualize relationships between them, and to explore relationships between gene clusters (programmes) and cell clusters (cell types). AVAILABILITY AND IMPLEMENTATION: CatsCradle is available freely as an R Bioconductor package (https://bioconductor.org/packages/CatsCradle) and interfaces directly with Seurat (Hao et al. 2024) and SingleCellExperiment (Amezquita et al. 2020) data structures.
MOTIVATION: Genomic alterations in cancer arise from selective pressures acting on hallmark molecular modules, layered over a background of random mutagenic events. Methods to detect selection at the level of modules, as opposed to genes or nucleotides, are relatively underdeveloped. RESULTS: Here we present CanSRMaPP (Cancer Selection Recovery by Maximum Posterior Probability), a Bayesian model of the cancer genome that infers mutational selection on single genes and multi-genic modules while simultaneously modeling background events. Applying CanSRMaPP to lung adenocarcinoma genomes, we identify positive selection on 63 modules, yielding a model that parsimoniously explains the observed pattern of genetic alterations observed in new cancer cohorts. We further show that CanSRMaPP is adaptable to more tumor types and to alternative module definitions. We show that these modules serve as an effective scaffold for translating the cancer genome to molecular states, with prediction of cancer biomarker status as demonstration. AVAILABILITY: CanSRMaPP is freely available on GitHub. SUPPLEMENTARY INFORMATION: Supplementary Figs. S1-5, Supplementary Tables S1-5, and Supplementary Notes 1 and 2 are available at Bioinformatics online.
OBJECTIVE: Streptomyces californicus strain ADR1 is an endophytic actinobacterium isolated from Datura metel that produces secondary metabolites with potent antibacterial and anti-biofilm activities against WHO-listed high-priority Gram-positive pathogens. While anti-bacterial and antioxidant potential of the strain ADR1 has been extensively characterized, its complete genome sequence remains to be investigated for further insights into its biosynthetic potential. This study presents the complete genome sequence analysis of the strain ADR1 to provide a robust genomic foundation for understanding its metabolic versatility and biosynthesis of compounds with therapeutic significance. DATA DESCRIPTION: The ADR1 genome was sequenced using Illumina HiSeq. The assembly comprised 262 scaffolds with a total genome size of 8.4 Mb and G + C content of 72.5%, containing 7427 protein-coding genes. AntiSMASH and IIT-Hyderabad novelBGC analysis revealed 39 biosynthetic gene clusters, including non-ribosomal peptide synthetases, type I polyketide synthases, terpene and melanin clusters, correlating with the diverse therapeutic compounds previously identified through GC-MS analysis. This high-quality genome provides crucial insights into the biosynthetic potential underlying potent antimicrobial and antioxidant activities of the strain ADR1.
INTRODUCTION: The genus Micromonospora is a prolific producer of specialized metabolites with pharmacological and agronomic relevance. Natural products derived from the genus Micromonospora have a distinctive chemical diversity and enormous therapeutic potential, thus represent a potential source for drugs and drug leads. OBJECTIVE: To explore the biosynthetic potential of four Micromonospora strains isolated from cold desert of NW Himalayas through genome mining and to correlate predicted biosynthetic gene clusters with chemical features detected by untargeted LC-HRMS metabolomics. METHOD: High-quality genomes were annotated for BGCs and matched against untargeted LC-HRMS features (peak picking, alignment, and annotation to chemical classes). Each isolate was grown in triplicate, and fermented broth was pooled for further metabolomic studies. RESULTS: By integrating genomic and metabolomic approaches, specialized biosynthetic gene clusters and strain-based putative metabolite classes were identified. LRS1 showed elevated xanthines (RiPP/siderophore), LRS3 had phenolic glycosides (hybrid PKS/NRPS), LRS4 showed 70-fold hydroxycinnamate enrichment (Type II PKS), and LRS5 displayed p-benzoquinone enrichment (Type III PKS). The metabolite profile of each strain aligned with its predicted biosynthetic gene cluster composition. CONCLUSION: Under a single growth regime, each Micromonospora strain exhibits a distinct metabolomic profile. This metabologenomics workflow can be further explored to isolate specialized metabolites with potential therapeutic and agricultural value.
MOTIVATION: Biosynthetic gene clusters (BGCs) are responsible the biosynthesis of many natural products, including a multitude of effective therapeutics and their precursors. Advances in genomic data collection as well as computational techniques have made it possible to identify BGCs at scale. However, accurately determining the types of BGC-encoded products from genomic content remains elusive. RESULTS: Here, we introduce BGC annotation tool (BGCat), a machine learning method for fine-grained structural classification of BGC-encoded products, leveraging the NPClassifier natural product nomenclature. Our method leverages a pre-trained protein language model for creating meaningful gene representations and a deep neural network for class label prediction. We show the method outperforms state-of-the-art approaches in coarse-grained product classification and is effective for detailed classification. We implement a clustering-based augmentation strategy for BGC-product relationships, addressing a crucial gap in the available datasets. We then introduce the concept of product class profiles of gene cluster families (GCFs), associating each GCF with a probabilistic distribution of product types and offering a new perspective on GCF functions. Lastly, we use BGCat to provide new product class labels for over 100k BGCs in antiSMASH DB that presently have minimal information about their products. AVAILABILITY AND IMPLEMENTATION: The source code and trained model weights are freely available at https://github.com/HassounLab/BGCat.
Lynch syndrome-associated urothelial carcinoma (LS-UC) is a rare and undercharacterized clinical entity. While FGFR3 alterations are well described in sporadic urothelial carcinoma, their prevalence and clinical implications in LS-UC remain unclear. We aimed to provide a comprehensive clinical and molecular characterization of LS-UC. We conducted a retrospective single-center study including patients with Lynch syndrome (LS) and histologically confirmed urothelial carcinoma (UC). Clinical, pathological, treatment, and follow-up data were collected. Targeted next-generation sequencing was performed on available tumor samples to assess genomic alterations, with particular attention to FGFR3 mutations. A total of 27 patients with LS-UC were identified, with a predominance of upper urinary tract involvement (70%). Most tumors were diagnosed at an early stage and initially managed with local treatment. During a median follow-up of 92 months, 48% of patients experienced recurrence, with a median time to recurrence of 37 months. Recurrences were predominantly local and were mainly managed with additional surgical or intravesical treatments. No deaths were attributable to UC at last follow-up. Molecular analysis was feasible in 9 cases. FGFR3 mutations were detected in 67% of evaluable samples, with the recurrent p.Arg248Cys hotspot identified in 55% of cases. Additional alterations involved TP53, SWI/SNF complex genes, and PIK3CA, which co-occurred with FGFR3 p.Arg248Cys. No gene fusions were identified. This study expands the limited molecular and clinical evidence on Lynch syndrome-associated urothelial carcinoma. Beyond confirming the recurrent role of FGFR3 (notably p.Arg248Cys), our comprehensive multigene profiling enriches the current genomic knowledge for this rare population. Multi-center collaborative efforts remain essential to aggregate larger datasets and ultimately guide personalized patient management.
β-Amino acid-containing macrolactams (β-AACMs) are a class of bioactive natural products characterized by nitrogen-containing starter units within polyketide-derived macrocycles. Here, we report four previously undescribed macrolactams, gruelactams A-D (1-4), from Nonomuraea sp. 0L2P, discovered through an integrated approach combining genome mining, 15N-labeling, and antibacterial screening. Their planar structures were elucidated by comprehensive spectroscopic analyses, including 1D and 2D NMR and HRESI-MS, and their configurations were partially assigned based on ROESY data and bioinformatic analysis. Genome sequencing and antiSMASH analysis identified a putative type I polyketide synthase (PKS) biosynthetic gene cluster, enabling the proposal of a biosynthetic pathway. Bioactivity assays showed that gruelactam D (4) exhibits antibacterial activity against Bacillus cereus and Staphylococcus aureus, with MIC values of 8 and 16 μg/mL, respectively. These findings expand the chemical diversity of β-AACMs and demonstrate the utility of genome-guided approaches for discovering bioactive natural products from rare actinomycetes.
Candida albicans uniquely possesses an expanded family of genes (the TLO gene family) that encodes 10-15 paralogues of the Med2 component of the transcriptional regulator Mediator. Previous studies have shown that TLO null mutants are unable to form hyphae and are hypersensitive to environmental stress. However, the reason for the TLO gene expansion remains unclear, and the current study aimed to determine if reduction in the TLO family copy number affected virulence. In order to investigate this, we used CRISPR-Cas9 mutagenesis to generate two TLO-depleted mutants: one mutant retaining only TLOβ2 (CaTLO2) and the second mutant containing only TLOγ5 (CaTLO5). Both TLO-depleted mutants exhibited increased filamentous growth, increased susceptibility to specific stresses and reduced virulence in a murine model of oropharyngeal candidiasis (OPC). In vitro, the CaTLO5 mutant also exhibited impaired hyphal escape from macrophages and reduced hyphal invasion of oral keratinocytes. We then investigated if complementation with TLOα1, a gene previously shown to restore wild-type growth in a Δtlo null mutant, could restore virulence. In vitro infection models showed that TLOα1 could restore true hypha formation, epithelial invasion and hyphal escape from macrophages in the CaTLO5 background. The murine OPC model showed that TLOα1 could restore wild-type virulence in both CaTLO2 and CaTLO5 strains, suggesting an essential role for α-TLO in oral mucosal infection. Together, these findings highlight the functional specialization between the α, β and γ TLO gene groups and establish α-TLO as a major regulator of virulence in C. albicans.
Entomopathogenic fungi of the genus Beauveria are widely used biological control agents that infect diverse insect hosts and can also associate with plants as rhizosphere colonizers and endophytes. Within this genus, Beauveria bassiana is a cosmopolitan generalist, whereas Beauveria brongniartii exhibits a narrower host range, primarily targeting soil-dwelling coleopteran larvae with limited evidence of plant colonization. To explore genomic differentiation associated with this ecological divergence, the commercially exploited B. brongniartii strain BIPESCO2 and B. bassiana ATHUM 4946 were sequenced using Oxford Nanopore technology, followed by comparative genomic analyses across multiple strains. Orthology identified species-specific gene families, although overall genome architecture and core gene content were highly conserved. The CAZyme repertoires were nearly identical, indicating retention of a versatile enzymatic toolkit supporting plant association, saprotrophy, and insect pathogenicity. In contrast, biosynthetic gene clusters displayed substantial variation, including structural remodeling of Beauveria-specific virulence-associated clusters and expansion of type I polyketide synthase clusters in B. brongniartii. Effector prediction revealed a conserved core of largely uncharacterized proteins alongside species-specific orthogroups enriched in adhesion-, immunity-, and cuticle-interaction domains. Together, these findings indicate that host-range divergence in Beauveria is associated with compartmentalized genomic differentiation, particularly in secondary metabolism and a limited subset of lineage-specific virulence factors, rather than in the conserved core infection machinery.