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At least 19 recordsLinked to original sources
PubMed2026

Chromosome engineering to correct a complex rearrangement on Chromosome 8 reveals the effects of 8p syndrome on gene expression and neural differentiation.

Chromosomal rearrangements on the short arm of Chromosome 8 cause 8p syndrome, a rare developmental disorder characterized by neurodevelopmental delays, epilepsy, and cardiac abnormalities. Although significant progress has been made in managing the symptoms of 8p syndrome and other conditions caused by large-scale chromosomal aneuploidies, no therapeutic approach has yet been demonstrated to target the underlying disease-causing chromosome. Here, we establish a two-step approach to eliminate the abnormal copy of Chromosome 8 and restore euploidy in cells derived from an individual with a complex rearrangement of Chromosome 8p. Transcriptomic analysis revealed 361 differentially expressed genes between the proband and the euploid revertant, highlighting genes both within and outside the 8p region that may contribute to 8p syndrome pathology. Furthermore, we demonstrate that the proband exhibits a significant defect in neural differentiation that could be partially rescued by treatment with small-molecule inhibitors of cell death. Our work demonstrates the feasibility of using chromosome engineering to correct complex aneuploidies in vitro and establishes a platform to further dissect the pathophysiology of 8p syndrome and other conditions caused by chromosomal rearrangements.

Humans↗
PubMed2026

Duplication-based genetic dissection of the Down syndrome critical region reveals its complex functional organization.

Down syndrome (DS), associated with trisomy 21, is the most common genetic cause of developmental delay and intellectual disability, yet the specific dosage-sensitive genes and the associated genetic mechanisms underlying these phenotypes remain incompletely defined. Here, we applied an additive genetic strategy to dissect the Down syndrome critical region (DSCR) by generating 2 complementary mouse models using Cre/loxP-mediated chromosome engineering that together span the entire DSCR on mouse chromosome 16: Dp(16)5Yey, duplicating the Setd4-Kcnj6 interval, and Dp(16)6Yey, duplicating the Kcnj15-Mx2 interval. In addition, we engineered a third duplication model, Dp(16)7Yey, carrying a selective duplication of the Dyrk1a-Kcnj6 interval containing only these 2 genes. Building upon our previously reported results, cognitive behavioral analyses of these 3 models reveal a complex functional genetic architecture of the DSCR, including dosage-sensitive genetic elements, interactions among these elements, and their contributions to DS-associated cognitive deficits. Together, these findings highlight the complexity of dosage-dependent genetic interactions, which provide important insights into DSCR functional organization and have major implications for the development of effective therapeutic strategies for DS-associated cognitive deficits. In addition, these duplication mouse models represent valuable resources for further genetic dissection of DS phenotypes beyond cognition.

Animals↗
PubMed2024

An increased copy number of glycine decarboxylase (GLDC) associated with psychosis reduces extracellular glycine and impairs NMDA receptor function.

Glycine is an obligatory co-agonist at excitatory NMDA receptors in the brain, especially in the dentate gyrus, which has been postulated to be crucial for the development of psychotic associations and memories with psychotic content. Drugs modulating glycine levels are in clinical development for improving cognition in schizophrenia. However, the functional relevance of the regulation of glycine metabolism by endogenous enzymes is unclear. Using a chromosome-engineered allelic series in mice, we report that a triplication of the gene encoding the glycine-catabolizing enzyme glycine decarboxylase (GLDC) - as found on a small supernumerary marker chromosome in patients with psychosis - reduces extracellular glycine levels as determined by optical fluorescence resonance energy transfer (FRET) in dentate gyrus (DG) and suppresses long-term potentiation (LTP) in mPP-DG synapses but not in CA3-CA1 synapses, reduces the activity of biochemical pathways implicated in schizophrenia and mitochondrial bioenergetics, and displays deficits in schizophrenia-like behaviors which are in part known to be dependent on the activity of the dentate gyrus, e.g., prepulse inhibition, startle habituation, latent inhibition, working memory, sociability and social preference. Our results demonstrate that Gldc negatively regulates long-term synaptic plasticity in the dentate gyrus in mice, suggesting that an increase in GLDC copy number possibly contributes to the development of psychosis in humans.

Animals↗
PubMed2025

Genomics-enabled dissection of sea wheatgrass genome for advancing wheat genetic resources.

Wheat production is challenged by biotic and abiotic stresses. Alien gene transfer is an effective approach to tackle such challenges. We previously showed that sea wheatgrass (SWG; Thinopyrum junceiforme (2n = 2x = 28; J1J2) is an untapped resource possessing resistance to an array of pests and abiotic stress. However, the transfer of these important traits has been hindered by the lack of genomic resources and a clear picture of its genome constitution. Using multi-color genomic in situ hybridization, we distinguished the SWG sub-genomes and corroborated that the J1 sub-genome is closely related to the E genome of Th. elongatum and the J genome of Th. bessarabicum and the J2 sub-genome to the V genome of Dasypyrum villosum. Meanwhile, we developed a draft SWG genome assembly and 127 SWG-specific DNA markers covering the 14 SWG chromosomes. Screening a population of 466 BC2F1 and BC2F2 individuals, derived from backcrosses of wheat-SWG amphiploid to wheat, by the SWG-specific markers led to selection of 72 plants putatively carrying one or two SWG chromosomes. The genome painting analysis of the 72 plants eventually identified a set of 37 wheat-SWG chromosome addition lines covering all the 14 pairs of SWG chromosomes and two compensating Robertsonian translocations (RobTs). While the wheat-SWG chromosome addition lines and RobTs are invaluable genetic resources for wheat improvement via chromosome engineering, our results showed the power of genome-specific markers in combination with genome painting in dissection of a polyploid genome and implicated the origin of a group of important polyploid grasses.

Triticum↗
PubMed2025

Turbo-charging crop improvement: harnessing multiplex editing for polygenic trait engineering and beyond.

Multiplex CRISPR editing has emerged as a transformative platform for plant genome engineering, enabling the simultaneous targeting of multiple genes, regulatory elements, or chromosomal regions. This approach is effective for dissecting gene family functions, addressing genetic redundancy, engineering polygenic traits, and accelerating trait stacking and de novo domestication. Its applications now extend beyond standard gene knockouts to include epigenetic and transcriptional regulation, chromosomal engineering, and transgene-free editing. These capabilities are advancing crop improvement not only in annual species but also in more complex systems such as polyploids, undomesticated wild relatives, and species with long generation times. At the same time, multiplex editing presents technical challenges, including complex construct design and the need for robust, scalable mutation detection. We discuss current toolkits and recent innovations in vector architecture, such as promoter and scaffold engineering, that streamline workflows and enhance editing efficiency. High-throughput sequencing technologies, including long-read platforms, are improving the resolution of complex editing outcomes such as structural rearrangements-often missed by standard genotyping-when targeting repetitive or tandemly spaced loci. To fully realize the potential of multiplex genome engineering, there is growing demand for user-friendly, synthetic biology-compatible, and scalable computational workflows for gRNA design, construct assembly, and mutation analysis. Experimentally validated inducible or tissue-specific promoters are also highly desirable for achieving spatiotemporal control. As these tools continue to evolve, multiplex CRISPR editing is poised to become a foundational technology of next-generation crop improvement to address challenges in agriculture, sustainability, and climate resilience.

Gene Editing↗
PubMed2025

Combinatorial genome engineering of pseudorabies virus Bartha by developing a reverse genetic system based on three overlapping genomic segments.

INTRODUCTION: The 138-kilobase genome of pseudorabies virus vaccine strain Bartha K61 harbors many nonessential genes for replication and exhibits remarkable capacity for incorporating foreign genes for therapeutic applications. However, the large size of the Bartha genome complicates its efficient engineering. OBJECTIVES: Development of a reverse genetic system for pseudorabies virus Bartha based on three overlapping genomic segments to facilitate multiplex genome engineering. METHODS: The 138-kb genome of Bartha was split into three overlapping segments (42 kb, 43 kb, and 53 kb), each cloned in a bacterial artificial chromosome (BAC) to facilitate genome engineering. The infectious virus was reconstituted by transfecting the 3 genomic fragments released from the BACs into Vero cells in which a complete virus genome was assembled using 2-kb overlaps between adjacent pieces. RESULTS: Employing the reverse genetic system, we individually deleted 15 candidate nonessential genes and confirmed that 10 were dispensable for viral growth in cell culture. Deletion of 7 nonessential genes had no impact on viral growth, whereas UL47 deletion reduced viral growth rate and deletions of UL44, UL47, or US3 resulted in smaller viral plaques. A total of 45 viral genomes with double deletions of nonessential genes were constructed, among which 22 were successfully rescued into infectious virions. Fifteen double-deletion mutant viruses had a viral titer comparable with the wild-type Bartha, while the remaining 7 showed a lower titer. Additionally, expressions of the mNeonGreen reporter gene at nonessential gene loci were evaluated. Cells infected with recombinant viruses carrying mNeonGreen at 8 loci showed strong green fluorescence, whereas those with mNeonGreen at 2 loci exhibited very weak fluorescence. CONCLUSION: The reverse genetic system developed in this study enables rapid and combinatorial engineering of viruses with the large DNA genome, and will accelerate development of large DNA virus-based therapeutics including live-attenuated vaccines, vector vaccines, and oncolytic herpesviruses.

Herpesvirus 1, Suid↗
PubMed2026

Periplasmic SacB as a robust counter-selection tool for genome engineering in the polyploid bacterium Zymomonas mobilis.

UNLABELLED: The alpha-proteobacterium Zymomonas mobilis exhibits exceptional ethanologenic physiology, which makes it a traditional alcoholic beverage producer and a promising chassis for biofuel production. Although genetic tools for this organism have expanded in recent years, a fundamental aspect of its chromosome organization remains to be understood. In particular, Z. mobilis has been suggested to exhibit polyploidy, but this feature is not fully confirmed because of discrepancies among studies reporting the copy number of chromosomes. Here, we tagged the chromosome-partitioning protein ParB with a fluorescent marker to visualize its cellular localization and estimate chromosome copy number in individual cells. Imaging showed that Z. mobilis exhibits several distinctive ParB foci throughout the cytoplasm and an accumulated focus at the pole, indicating that a single Z. mobilis cell contains >5 copies of the chromosome at the oriC regions. We then sought to establish an efficient counter-selection system, which is crucial for engineering multiple copies of the chromosome. We assessed the efficacy of levan-sucrase (SacB) toxicity in Z. mobilis. We found that, despite Z. mobilis secreting a native extracellular sucrase SacB, heterologous periplasmically localized Bacillus subtilis SacB rendered Z. mobilis cells sensitive to sucrose. We successfully used this effect for counter-selection when deleting and inserting targeted DNA sequences into the Z. mobilis genome. Together, this work provides important insights and tools for advancing Z. mobilis genetics and its biotechnological applications. IMPORTANCE: Zymomonas mobilis is a promising industrial bacterium with the capacity to convert sugars into ethanol at nearly maximum theoretical yield. With its expanding use in industrial applications, it is crucial to clarify if individual Z. mobilis cells carry multiple copies of the chromosome, as this has important implications for genome engineering. Two previous studies have used quantitative PCR to address this question, but their reported chromosome copy numbers varied widely from 20 to 100. Here, we used a cell biological approach to estimate the copy number and confirmed that a single Z. mobilis cell possesses multiple copies. In addition, we show that a SacB-based counter-selection works in Z. mobilis, enabling efficient and complete mutation of all chromosome copies.

Zymomonas↗
PubMed2026

Hi-C calibration by chemically induced chromosomal interactions.

The genome-wide chromosome conformation capture method, Hi-C, has greatly advanced our understanding of genome organization. However, its quantitative properties, including sensitivity, bias, and linearity, remain challenging to assess. Measuring these properties in vivo is difficult due to the heterogenous and dynamic nature of chromosomal interactions. Here, using Chemically Induced Chromosomal Interaction (CICI) method, we create stable intra- and inter-chromosomal interactions in G1-phase budding yeast across a broad range of contact frequencies. Hi-C analysis of these engineered cell populations demonstrates that static intra-chromosomal loops do not generate Topologically Associated Domains (TADs) and only promote 3D proximity within 10-60 kb flanking regions. At moderate sequencing depth, Hi-C is sensitive enough to detect interactions occurring in 5-10% of cells. It also shows no inherent bias toward intra- versus inter-chromosomal interactions. Furthermore, we observe a linear relationship between Hi-C signal intensity and contact frequency. These findings illuminate the intrinsic properties of the Hi-C assay and provide a robust framework for its calibration.

Chromosomes, Fungal↗
PubMed2026

Systematic modular engineering of genome-integrated Escherichia coli MG1655 for high-level 2'-fucosyllactose production.

2'-Fucosyllactose (2'-FL), the most abundant human milk oligosaccharide (HMO), has attracted considerable interest for its prebiotic and immunomodulatory functions, with broad applications in infant nutrition. In this study, we report the development of a high-yield, genome-integrated 2'-FL-producing strain based on Escherichia coli MG1655 through systematic modular optimization. Starting from a single-copy BKHT strain (MGC06), we first optimized the copy number of the α-1,2-fucosyltransferase (α-1,2-FT) gene BKHT. Subsequently, the GDP-L-fucose supply was enhanced through coordinated genomic integration of the gene clusters cpsG-cpsB and gmd-fcl, while the multidrug efflux transporter gene mdfA was integrated to improve product export and strain robustness. BKHT copy number was then re-evaluated in the optimized background, with four copies yielding the highest production. The final engineered strain, harboring all genetic modifications stably integrated into the chromosome, produced 17.18 g/L 2'-FL in shake-flask culture. In fed-batch fermentation using a 5-L bioreactor, this strain achieved a titer of 154.12 g/L after 60 h, with a productivity of 2.57 g/L/h. Notably, throughout the entire fermentation process, no antibiotics or inducers were supplemented, underscoring the genetic stability and regulatory compliance of this plasmid-free system. To our knowledge, this represents the highest 2'-FL titer reported to date, positioning our engineered strain as a promising candidate for commercial 2'-FL production.

Escherichia coli↗
PubMed2025

Genome-wide profiling the integration patterns with T7-PCR.

Integration of exogenous gene fragments into the host genomes is a widely used and powerful method for studying gene functions, advancing molecular breeding, and conducting gene therapy. Accurately identifying the integration sites is essential for ensuring both the safety and efficacy of genome engineering efforts. However, current mapping techniques are constrained by high costs and a low signal-to-noise ratio. In this study, we developed an innovative tool for mapping integration sites, leveraging T7 polymerase-mediated in vitro transcription (T7-IVT) to capture the junction fragments surrounding integration loci. This approach converts genomic flanking sequences into RNA, enabling the simultaneous enrichment of junction fragments and the elimination of background genomic DNA, thereby significantly enhancing the signal-to-noise ratio. We have validated the efficiency of this method, named T7-PCR, across yeast, plant, and human cells under diverse integration scenarios. T7-PCR outperforms current next-generation sequencing (NGS)-based mapping strategies in terms of efficiency and accuracy, with minimal positional effects. This method is highly applicable for high-throughput transgene screening and also supports the development of next-generation tools for targeted integration of large fragments.

Humans↗
PubMed2026

High-throughput recovery of integron cassettes for gene discovery screens.

Integrons capture functional genes in mobile genetic elements called integron cassettes, which represent an untapped source of genes of biotechnological interest. Here we present two tools, cassette gatherer and cassette hunter, that enable high-throughput establishment of gene libraries either from genetically tractable strains or directly from DNA. We re-engineered a class 1 integron into counterselection markers on a plasmid or on the chromosome of a naturally competent Vibrio cholerae, which enabled capture of single cassettes in a sequence- and function-independent manner. When applied to Vibrio strains and genomic libraries, our tools recovered hundreds of single cassettes per assay with more than 99% specificity. We further subjected the library of cassettes generated by the hunter and gatherer tools to screens against phages ICP2 and T4, and identified nine phage-defence systems, including five previously undescribed. These tools enable rapid and large-scale recovery of integron cassettes that could be leveraged for functional gene discovery.

Journal Article↗
PubMed2026

Prophage landscapes in clinical MRSA: safety profiling and discovery of Lys81, a broad-spectrum bacteriolytic enzyme.

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant threat to global healthcare, requiring novel therapeutic strategies. Prophages, latent phage genomes integrated into bacterial chromosomes, are important resources for antimicrobial development due to their genomic stability and genetic engineering potential. METHODS: In this study, we performed genomewide sequencing on 329 MRSA isolates to predict prophage sequences, followed by analyses of these prophages-including examinations of virulence genes, antibiotic resistance genes, homologous proteins of pathogenic MRSA phages, and functional predictions of these homologous proteins-to evaluate their safety and value as genetic engineering scaffolds and to screen for novel broadspectrum bacteriolytic enzymes. RESULTS: Our data indicate that 85.7% (282/329) of strains carried complete prophage sequences; 64 strains lacked virulence factors or genes, meeting the core criteria for safe vectors. Resistance screening found only 6 prophages carried msrA, confirming the biosafety of the remaining strains. A significant correlation existed between prophage virulence gene capacity and genomic structure (R2 = 0.99986684, p = 3.64e-69). High-virulence clusters (>10 factors) showed high structural similarity; 10 characteristic sequences linked to S. aureus phages and their prevalence patterns were identified via conserved motif analysis. Collinearity analysis with reference to virulent MRSA phages and 3D structural predictions of orthologous proteins identified two lysozymes and a host-recognition device. Notably, Lys81, an N-acetylmuramoyl-L-alanine amidase ortholog, was prioritized and characterized as a broad-spectrum lytic enzyme. Our data show Lys81 has key properties: (1) Broad-spectrum antibacterial activity, lysing 52.3% (23/44) of clinical S. aureus strains and cross-acting against Gram-positive bacteria such as Pseudomonas aeruginosa and Listeria; (2) Excellent environmental adaptability, maintaining activity at pH 5.0 and 0°C, with 25 mM Na+ and Ca2 + enhancing function; (3) Potent biofilm clearance, achieving 83% MRSA biofilm reduction at 50 μg/mL; and (4) Favorable in vivo safety/efficacy, eradicating MRSA infections in lung organoid models with minimal cytotoxicity. DISCUSSION: This study establishes a theoretical foundation for the clinical translation of MRSA prophages, positioning Lys81 as a novel candidate for treating drug-resistant bacterial infections.

Lys81↗
PubMed2025

Integrated epigenetic and genetic programming of primary human T cells.

Targeted epigenetic engineering of gene expression in cell therapies would allow programming of desirable phenotypes without many of the challenges and safety risks associated with double-strand break-based genetic editing approaches. Here, we develop an all-RNA platform for efficient, durable and multiplexed epigenetic programming in primary human T cells, stably turning endogenous genes off or on using CRISPRoff and CRISPRon epigenetic editors. We achieve epigenetic programming of diverse targeted genomic elements without the need for sustained expression of CRISPR systems. CRISPRoff-mediated gene silencing is maintained through numerous cell divisions, T cell stimulations and in vivo adoptive transfer, avoiding cytotoxicity or chromosomal abnormalities inherent to multiplexed Cas9-mediated genome editing. Lastly, we successfully combined genetic and epigenetic engineering using orthogonal CRISPR Cas12a-dCas9 systems for targeted chimeric antigen receptor (CAR) knock-in and CRISPRoff silencing of therapeutically relevant genes to improve preclinical CAR-T cell-mediated in vivo tumor control and survival.

Humans↗
PubMed2026

Genomic characterization of the attenuated human cytomegalovirus strain TR-VAC developed for subviral particle vaccine production.

We report the complete genome sequence of the attenuated human cytomegalovirus strain TR-VAC, developed for subviral particle vaccine production. Oxford Nanopore duplex sequencing confirmed all engineered modifications, including UL130 repair, UL25 stop codons, ddFKBP insertion, GFP deletion, and retention of the bacterial artificial chromosome backbone, without large-scale structural rearrangements.

Human cytomegalovirus↗
PubMed2026

CRISPR-Engineered CAR-T Cell Therapy for Epstein-Barr Virus-Associated Nasopharyngeal Carcinoma: A Review of Emerging Therapeutic Prospects.

Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) remains a clinically challenging malignancy, particularly in recurrent or metastatic disease where durable responses to chemoradiotherapy and immune checkpoint blockade are limited. The viral aetiology of NPC provides a strong biological rationale for immune-based treatment; however, translation of chimaeric antigen receptor (CAR) T-cell therapy into this solid tumour setting is constrained by poor tumour trafficking, antigen heterogeneity, limited surface accessibility of EBV latent antigens, T-cell exhaustion, and an immunosuppressive tumour microenvironment. This review critically evaluates the emerging therapeutic prospects of CRISPR-engineered CAR-T cell therapy for EBV-associated NPC. It synthesises evidence on EBV latency biology, NPC immune evasion, solid-tumour CAR-T limitations, and genome-engineering strategies including conventional CRISPR-Cas9, base editing, prime editing, and double-strand-break-sparing targeted integration. Particular attention is given to genotoxicity, chromosomal rearrangements, chromosome loss, bystander and off-target editing, manufacturing heterogeneity, and the regulatory and biological barriers that currently separate technical feasibility from NPC-specific clinical implementation. Available clinical evidence from checkpoint blockade, EBV-specific adoptive T-cell therapy, base-edited CAR-T cells in haematologic malignancy, and early CRISPR-edited T-cell trials supports the feasibility of immune and genetic redirection but does not establish efficacy of a clinically validated CRISPR-engineered CAR-T platform for NPC. Future development should prioritise surface-accessible antigen validation, fit-for-purpose selection of editing technology, genomic safety, scalable manufacturing, and biomarker-driven early-phase trials.

Humans↗
PubMed2026

Transcriptional perturbation of LINE-1 elements reveals their cis-regulatory potential.

Long interspersed element-1 (LINE-1 or&#xa0;L1) retrotransposons constitute the largest transposable element family in mammalian genomes and contribute prominently to inter- and intra-individual genetic variation. Although most L1 elements are inactive, some evolutionary younger elements remain intact and genetically competent for transcription and occasionally retrotransposition. Despite being generally more abundant in gene-poor regions, intact or full-length L1s (FL-L1) are also enriched around specific classes of genes and on the eutherian X chromosome. How proximal FL-L1 may affect nearby gene expression remains unclear. Here, we examine this systematically using engineered mouse embryonic stem cells (ESCs) in which expression of one active L1 subfamily is perturbed. We find that FL-L1 activation leads to the misregulation of ~1024 genes, whereas FL-L1 repression affects ~81 genes. In most cases (68%), misexpressed genes contain an intronic FL-L1 or lie near a FL-L1 (<&#x2009;260&#x2009;kb). Gene ontology analysis shows that upon L1 activation, upregulated genes are enriched for neuronal function-related terms, suggesting that some L1 elements may have evolved to control neuronal gene networks. These results illustrate the cis-regulatory potential of FL-L1 elements and suggest a broader role for L1s than originally anticipated.

Animals↗
PubMed2026

PangyPlot: multi-scale interactive visualization of pangenome variation graphs.

SUMMARY: Pangenome variation graphs integrate multiple samples into a unified representation, mitigating the reference bias inherent to linear genomes. However, these graphs can be large and structurally complex. Existing visualization tools are each confined to a fixed scale of resolution, requiring researchers to switch between multiple tools to examine variation at different levels of detail. PangyPlot is an interactive pangenome browser designed for multi-scale exploration of reference variation graphs from full chromosome to nucleotide-level sequence segments. PangyPlot anchors navigation to linear reference coordinates, organizes variation into hierarchical bubble structures, and uses a force-directed layout engine for automatic node arrangement. AVAILABILITY AND IMPLEMENTATION: An instance preloaded with data is available at https://pangyplot.research.sickkids.ca. Source code and documentation are openly available at https://github.com/strug-hub/pangyplot under the MIT License.

Software↗
PubMed2026

Rewiring Carbon Metabolism in Bacillus methanolicus via Heterologous Phosphoketolase Expression Enhances Biomass Yield From Methanol and Reduces CO2 Loss.

Methylotrophic microbes are attractive alternatives to traditional heterotrophic production platforms, yet their efficiency is constrained by carbon loss through pyruvate decarboxylation and the oxidative branch of the RuMP cycle. The phosphoketolase (PKT) pathway provides a carbon-conserving alternative by cleaving fructose-6-phosphate and/or xylulose-5-phosphate into acetyl-phosphate, which can subsequently be converted to acetyl-coA without pyruvate decarboxylation. The remaining carbon intermediates are recycled through central metabolism to regenerate RuMP cycle intermediates without direct CO2 release. Here, we engineered this strategy in Bacillus methanolicus, a thermophilic methylotroph with strong industrial potential. We first established a versatile expression toolkit comprising inducible and constitutive promoters, benchmarked using an sfGFP reporter. Leveraging this system, we heterologously expressed the phosphoketolase B (pktB) gene from Methylotuvimicrobium buryatense 5GB1C which increased methanol-to-biomass yields by 18%-24% relative to controls and reduced biogenic CO2 production by 9%-12%. Chromosomal integration of pktB preserved these gains, demonstrating stability without reliance on plasmid-based expression. Together, these results show that PKT-driven metabolic rewiring enhances substrate yields in B. methanolicus and provides a scalable strategy to improve methylotrophic bioprocesses. This work expands the metabolic engineering toolbox for methylotrophs and highlights carbon-conserving pathway design as a key lever for advancing single carbon (C1) biomanufacturing.

Bacillus↗