Nosocomial infections caused by Pseudomonas aeruginosa (P. aeruginosa) have become increasingly common, particularly among immunocompromised individuals, who experience high mortality rates and prolonged treatment durations due to the limited availability of effective therapies. In this study, we screened for anti-ExoS compounds targeting P. aeruginosa and identified pycnogenol (PYC) as a potent inhibitor of the type III secretion system (T3SS), a major virulence mechanism responsible for the translocation of effectors such as ExoS. Using ELISA, western blotting, and real-time PCR analyses in both P. aeruginosa and infected H292 cells, we found that PYC significantly reduced T3SS activity. Mechanistically, PYC suppressed the transcription of T3SS-related genes by downregulating exsA expression in P. aeruginosa. Furthermore, pretreatment with PYC attenuated the cytotoxic effects and reduced the expression of proinflammatory cytokines, including interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-18 (IL-18), in P. aeruginosa-infected H292 cells. These effects were associated with the inhibition of NF-κB signaling and inflammasome activation. Taken together, our findings suggest that PYC may serve as a promising therapeutic candidate against P. aeruginosa infections by targeting T3SS-mediated virulence and modulating host inflammatory responses.

Yeast prion [PSI+], an amyloid form of the translation termination factor Sup35p/eRF3, causes translational stop codon readthrough by sequestering functional Sup35p. This unique phenotype may be analyzed via [PSI+]−suppressible nonsense alleles, and has greatly contributed to the advancement in yeast prion research. For comparing canonical reporters, like chromosomal ade1−14 or ade2−1, and plasmid-borne ura3−14, the de novo generation and characteristics of [PSI+] was investigated across common yeast laboratory strains (BY4741, 74D−694, and 779−6A). The results showed significant variability in [PSI+] induction frequency among strains. [PSI+] was successfully induced in BY4741 and frequently in 74D−694 (via Ade⁺ selection), but not in 779−6A. Notably, [PSI+] clones, even from identical genetic backgrounds, displayed vastly different nonsense suppression phenotypes depending on the reporter allele used; resulting in diverse growth patterns and suppression levels. Quantitative analyses revealed that prion seed counts fluctuated significantly based on the detection allele and observed phenotype. Furthermore, Sup35p aggregate visualization revealed distinct structural patterns between BY4741 and 74D−694, indicating strain-specific differences. Transferring [PIN+] prion variants from different strains into a common [psi−][pin−] background yielded similar [PSI+] inducibility and seed numbers, suggesting that the observed phenotypic and quantitative diversities of [PSI+] prions stem primarily from the interplay between the specific reporter detection system and the host strain's genetic background rather than solely from inherent differences in the initial [PIN+] prion or fundamental changes in the [PSI+] protein itself. This study underscores the crucial need to consider both the detection methodology and host genetic context for accurate prion variant characterization.

Human papillomaviruses (HPVs) cause abnormal cellular proliferation, leading to malignant or benign lesions, such as cervical cancer and warts. The genome of HPV16, the most prevalent high-risk oncogenic genotype within the Alphapapillomavirus genus, encodes two oncoproteins. One of these proteins, E7, interacts with multiple host proteins and modulates their functions through distinct pathways. The CR2 domain of HPV16 E7 was recently reported to interact with the μ2 subunit of clathrin-adaptor protein 2 (AP2-μ2), an adaptor complex involved in cargo internalization during clathrin-mediated endocytosis. In this study, to provide molecular insights into their intermolecular interactions, we determined the crystal structures of AP2-μ2 in complex with the HPV16 E7-derived peptides. Subsequent biochemical analyses revealed that this interaction is primarily maintained by the Y-x-x-Φ motif and further supported by acidic cluster residues of HPV16 E7. Finally, sequence alignment of the E7 CR2 domains from various HPV genotypes showed that the AP2-μ2-binding motif is largely conserved in Alpha-, Beta-, and Mupapillomaviruses, but not in Nu- and Gammapapillomaviruses.

CRISPR-Cas technologies have emerged as powerful and versatile tools in gene therapy. In addition to the widely used SpCas9 system, alternative platforms including modified amino acid sequences, size-optimized variants, and other Cas enzymes from diverse bacterial species have been developed to apply this technology in various genetic contexts. In addition, base editors and prime editors for precise gene editing, the Cas13 system targeting RNA, and CRISPRa/i systems have enabled diverse and adaptable approaches for genome and RNA editing, as well as for regulating gene expression. Typically, CRISPR-Cas components are transported to the target in the form of DNA, RNA, or ribonucleoprotein complexes using various delivery methods, such as electroporation, adeno-associated viruses, and lipid nanoparticles. To amplify therapeutic efficiency, continued developments in targeted delivery technologies are required, with increased safety and stability of therapeutic biomolecules. CRISPR-based therapeutics hold an inexhaustible potential for the treatment of many diseases, including rare congenital diseases, by making permanent corrections at the genomic DNA level. In this review, we present various CRISPR-based tools, their delivery systems, and clinical progress in the CRISPR-Cas technology, highlighting its innovative prospects for gene therapy.

Strains Mo2-6^T, S9, KG4-3^T, and 50Mo3-2, identified as coagulase-negative, Gram-stain-positive, halotolerant, non-motile coccoid bacteria, were isolated from traditional Korean soybean foods. Strains Mo2-6^T and S9 were both catalase- and oxidase-negative, whereas KG4-3^T and 50Mo3-2 were catalase-positive but oxidase-negative. The optimal growth conditions for Mo2-6^T and S9 were 30°C, 2% NaCl, and pH 7.0, while KG4-3^T and 50Mo3-2 grew best at 35°C, 2% NaCl, and pH 7.0. All strains contained menaquinone-7 as the predominant isoprenoid quinone, with anteiso-C_15:0 and iso-C_15:0 as the major cellular fatty acids (> 10%). Additionally, anteiso-C_13:0 was a major fatty acid in strain KG4-3^T. The DNA G + C contents of strains Mo2-6^T, S9, KG4-3^T, and 50Mo3-2 were 33.4%, 33.3%, 32.5%, and 32.7%, respectively. Phylogenetic analyses based on the 16S rRNA gene and whole-genome sequences revealed that strains Mo2-6^T and S9, as well as KG4-3^T and 50Mo3-2, formed distinct lineages within the genus Staphylococcus. Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses confirmed that strains Mo2-6^T and S9, as well as KG4-3^T and 50Mo3-2, belonged to the same species. Meanwhile, dDDH and ANI values between strains Mo2-6^T and KG4-3^T, as well as comparisons with other Staphylococcus type strains, were below the species delineation thresholds, indicating they represent novel species. Based on phenotypic, chemotaxonomic, and molecular data, we propose strain Mo2-6^T as the type strain of Staphylococcus parequorum sp. nov. (=KACC 23685^T =JCM 37038^T) and strain KG4-3^T as the type strain of Staphylococcus halotolerans sp. nov. (=KACC 23684^T =JCM 37037^T).

Akkermansia muciniphila (AKK, A. muciniphila) fortifies the intestinal barrier, inhibits the colonization of pathogenic bacteria, and protects the host’s health. Nevertheless, the existing literature offers inadequate evidence to ascertain whether A. muciniphila can effectively treat Candida albicans (C. albicans) infections in vitro, and the underlying mechanisms remain ambiguous. This study, animal models were established through gavage with clinical isolates of C. albicans to induce gastrointestinal tract colonization and subsequent translocation infection. The models were subsequently administered A. muciniphila. We examined the analysis of 16S rRNA gene sequencing, metabolomics of colonic contents, and transcriptomics of colonic tissue. The intestinal barrier, inflammatory responses, and immune cell infiltration are analyzed. This study revealed that A. muciniphila markedly mitigated C. albicans translocation infection and modified the intestinal microbial community structure and metabolic attributes in model mice. After administering A. muciniphila to the translocation infection group, there was a notable increase in the prevalence of bacteria that produce short-chain fatty acids, including Eubacterium_F. Moreover, there was a significant increase in the levels of specific pathogens, including Faecalibaculum, Turicibacter, and Turicimonas. The study demonstrated that A. muciniphila treatment can improve the composition of intestinal microbiota and metabolites, augment the tight junctions of colonic tissue and diminish systemic inflammatory response. This presents an innovative therapeutic approach for the potential treatment of intestinal C. albicans infection using A. muciniphila.

CRISPR-Cas9-based gene editing enables precise genetic modifications. However, its application to human cytomegalovirus (HCMV) remains challenging due to the large size of the viral genome and the essential roles of key regulatory genes. Here, we establish an optimized CRISPR-Cas9 system for precise labeling and functional analysis of HCMV immediate early (IE) genes. By integrating a multifunctional cassette encoding an auxin-inducible degron (AID), a self-cleaving peptide (P2A), and GFP into the viral genome via homology-directed repair (HDR), we achieved efficient knock-ins without reliance on bacterial artificial chromosome (BAC) cloning, a labor-intensive and time-consuming approach. We optimized delivery strategies, donor template designs, and component ratios to enhance HDR efficiency, significantly improving knock-in success rates. This system enables real-time fluorescent tracking and inducible protein degradation, allowing temporal control of essential viral proteins through auxin-mediated depletion. Our approach provides a powerful tool for dissecting the dynamic roles of viral proteins throughout the HCMV life cycle, facilitating a deeper understanding of viral pathogenesis and potential therapeutic targets.

Extracellular vesicles derived from probiotics have received considerable attention for their pivotal role in bacterial‒host communication. These nanosized, bilayer-encapsulated vesicles carry diverse bioactive molecules, such as proteins, lipids, nucleic acids, and metabolites. Currently, ample evidence has emerged that probiotic extracellular vesicles may modulate several processes of host physiological hemostasis and offer therapeutic benefits. This review examines the biogenesis, composition, and immunomodulatory functions of probiotic-derived extracellular vesicles in probiotic–host interactions, highlighting the therapeutic potential of probiotic extracellular vesicles in the diagnosis and treatment of conditions such as cancer and inflammatory bowel disease. We further summarize the techniques for the separation and purification of extracellular vesicles, providing a methodological foundation for future research and applications. Although the field of probiotic extracellular vesicle research is still in its infancy, the prospects for their application in the biomedical field are broad, potentially emerging as a novel therapeutic approach.

Two rod-shaped, Gram-positive, spore-forming, motile, and strictly anaerobic bacteria, FM7315^T and FM7330^T were isolated from Myeolchi-jeot, a traditional Korean fermented anchovy. Phylogenetic and phylogenomic analyses based on the 16S rRNA gene and genome sequences revealed that strains FM7315^T and FM7330^T represent novel species within the genus Haloimpatiens. The genome sizes of strains FM7315^T and FM7330^T were 3,052,517 bp and 4,194,114 bp, respectively, with G + C contents of 29.7 mol% and 28.0 mol%, respectively. Strain FM7315^T exhibited growth at 20–37°C, 0–2% NaCl, and pH range of 5.0–8.0, whereas strain FM7330^T grew at 25–45°C, 0–4% NaCl, and pH range of 5.0–9.0. Strain FM7315^T contains C_14:0, C_16:0, C_18:1 ω9c, Summed Feature 3 (C_16:1 ω7c/C_16:1 ω6c), and Summed Feature 8 (C_18:1 ω7c/C_18:1 ω6c) as major fatty acids, along with diphosphatidylglycerol, phosphatidylglycerol, glycolipid, two aminophospholipids, and five unidentified lipids. Strain FM7330^T contains C_16:0, C_17:1 ω8c, and C_18:1 ω9c as major fatty acids, along with diphosphatidylglycerol, two phosphatidylglycerols, four aminophospholipids, and six unidentified lipids. Based on their phenotypic, chemotaxonomic, and molecular characteristics, strains FM7315^T and FM7330^T represent two novel species of the genus Haloimpatiens, for which the names Haloimpatiens sporogenes sp. nov. (FM7315^T = KCTC 25939^T = JCM 37574^T) and Haloimpatiens myeolchijeotgali sp. nov. (FM7330^T = KCTC 25938^T = JCM 37575^T) have been proposed.

Pectin-rich biomass, derived from fruit and citrus processing waste, presents a promising yet underutilized resource for sustainable biofuel and biochemical production. Its low lignin content and high concentrations of fermentable sugars, including D-galacturonic acid, L-arabinose, and D-xylose, make it an attractive feedstock. Unlike lignocellulosic biomass, pectin-rich hydrolysates require milder pretreatment, improving sugar recovery efficiency. However, industrial strains such as Saccharomyces cerevisiae exhibit strong glucose preference, limiting the efficient co-fermentation of mixed sugars. While prior reviews have broadly addressed lignocellulosic biomass utilization, this mini-review uniquely centers on the specific metabolic challenges and opportunities associated with pectin-rich feedstocks. In addition to incorporating established strategies for the co-utilization of cellobiose and xylose, we highlight recent advances that allow S. cerevisiae to metabolize carbon sources specifically from pectin-rich biomass, such as L-arabinose and D-galacturonic acid—monomers not prevalent in traditional lignocellulosic biomass. By integrating discussions on sugar transport engineering, redox balancing, and pathway optimization, this review offers a comprehensive framework to overcome glucose repression and support efficient co-fermentation of carbon sources from conventional and pectin-rich biomass. Drawing on these advances, we outline practical strategies to enhance fermentation performance and expand the valorization of food processing residues in biomanufacturing.

The global spread of COVID-19 has underscored the urgent need for advanced tools to study emerging coronaviruses. Reverse genetics systems have become indispensable for dissecting viral gene functions, developing live-attenuated vaccine candidates, and identifying antiviral targets. In this study, we describe a robust and efficient reverse genetics platform for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The system is based on the assembly of a full-length infectious cDNA clone from seven overlapping fragments, each flanked by homologous sequences to facilitate seamless assembly using the Gibson assembly method. Individual cloning of each fragment into plasmids enables modular manipulation of the viral genome, allowing rapid site-directed mutagenesis by fragment exchange. Infectious recombinant virus was successfully recovered from the assembled cDNA, exhibiting uniform plaque morphology and genetic homogeneity compared to clinical isolates. Additionally, fluorescent reporter viruses were generated to enable real-time visualization of infection, and the effects of different mammalian promoters on viral rescue were evaluated. This reverse genetics platform enables efficient generation and manipulation of recombinant SARS-CoV-2, providing a valuable resource for virological research and the development of preventive and therapeutic antiviral measures.

Opportunistic fungal pathogens, responsible for over 300 million severe cases and 1.5 million deaths annually, pose a serious global health threat, especially in immunocompromised individuals. Among these, Candida albicans is a major cause of both superficial and invasive infections, which can progress to systemic candidiasis. One of the critical factors in C. albicans pathogenicity is the yeast-to-hyphal transition, which enables biofilm formation and promotes tissue invasion through the secretion of candidalysin, a cytolytic peptide toxin encoded by the ECE1 gene. In this study, metabolites produced by Streptomyces ambofaciens CJD34, isolated from soil samples, were screened for antifungal activity. Methoxy-apo-enterobactin (compound 1) was identified as a potential inhibitor of C. albicans virulence. Treatment with compound 1 significantly suppressed ECE1 expression and candidalysin production. In a murine subcutaneous infection model, topical application of compound 1 reduced subcutaneous colonization by C. albicans. Molecular docking analysis suggested that the inhibition of ECE1 expression was not mediated by direct binding to known upstream transcription factors, indicating an indirect mechanism of action. Collectively, these findings highlight compound 1 as a promising antivirulence agent targeting candidalysin-mediated pathogenicity in C. albicans.

Photodynamic therapy (PDT) is a known strategy for treating cancer; in PDT, photosensitizers are activated by light stimulation and then induce reactive oxygen species (ROS) production to damage cancer tissues. Recently evidence has shown that PDT can also be used as a novel treatment strategy to control pathogenic bacteria. In previous studies, the photosensitizer DH-I-180-3 was reported to effectively regulate multidrug-resistant Mycobacterium tuberculosis growth. Here, we confirmed the effects of DH-I-180-3 on the antibacterial activity and inflammatory response of macrophages to Salmonella. Photoactivated DH-I-180-3 regulated intracellular bacterial growth in Salmonella-infected macrophages. Moreover, DH-I-180-3 increased intracellular ROS levels in Salmonella-infected macrophages. The phosphorylation of the intracellular signaling proteins IκBα and JNK1/2 was increased in DH-I-180-3-treated Salmonella-infected macrophages. Additionally, we observed that DH-I-180-3 significantly increased the mRNA expression and protein secretion of the proinflammatory cytokine TNF-α and promoted phagosome maturation by upregulating EEA1, LAMP1, and Cathepsin D in Salmonella-infected macrophages. Overall, these results demonstrate that photoactivated DH-I-180-3 enhances the bactericidal response to intracellular bacterial infection by promoting inflammatory signaling pathways and phagosome maturation. Therefore, DH-I-180-3 has the potential to be developed into PDT for treating bacterial-infection.

Heme oxygenase-1 (HO-1) has antioxidant, anti-apoptotic, and anti-inflammatory properties. Emerging evidence shows that HO-1 also exhibits antiviral activity against severe acute respiratory syndrome coronavirus 2, human immunodeficiency virus, hepatitis B virus, and Ebola virus. Its antiviral effects are mediated not only by its enzymatic function but also through the modulation of interferon-related pathways, thereby inhibiting viral replication. In this study, we investigated the antiviral effects of HO-1 on canine coronavirus (CCoV) and canine influenza virus (CIV) H3N2 using cell-based assays. To determine whether HO-1 suppresses CCoV and CIV, cells were treated with hemin to induce HO-1 expression. Hemin treatment successfully induced HO-1 expression in A72 and Madin-Darby canine kidney cells, resulting in the suppression of CCoV and CIV replication. The canine HO-1 gene was cloned into an expression vector and transfected into cells to achieve transient overexpression. Recombinant canine HO-1 protein was expressed in Escherichia coli and purified using an expression vector. HO-1 overexpression suppressed CCoV and CIV replication in cells. Following viral infection, treatment with purified HO-1 protein led to a reduction in viral protein levels. Therefore, both HO-1 expression and exogenous protein treatment effectively inhibited CCoV and CIV replication. Elevated HO-1 protein levels consistently reduced viral RNA and protein expression in vitro. These findings suggest that HO-1 could serve as a potential therapeutic agent for managing viral infections in dogs.

Spo0A, the master regulator of sporulation initiation in Bacillus subtilis, controls over 500 genes directly or indirectly in early sporulation stages. Although the effects of Spo0A disruption on sporulation have been extensively studied, a comprehensive understanding of the genomic response throughout growth phases remain elusive. Here, we examined the transcriptomic changes in Spo0A mutant strain, R211E, and wild-type across a time-course RNA-seq to identify impacted biological processes and pathways. The R211E strain, which exhibits sporulation deficiency, was constructed using the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated protein (Cas)9 system, highlighting the critical role of proper Cas9 dosing in gene editing. Functional analysis of 3,010 differentially expressed genes (DEGs) showed significant alterations in sporulation, quorum sensing, metabolism, and biofilm formation. The R211E disrupted the Spo0A-AbrB regulatory pathway, reducing biofilm formation and enhancing flagellar gene expression. Up-regulated metabolic pathways, including glycolysis, histidine, and purine biosynthesis, increased cell numbers during vegetative growth. Further, the mutant displayed elevated vegetative autolysin expression, resulting in reduced cell viability in the stationary phase. We also introduce the novel potential of R211E in a recombinant protein expression system that facilitated protein release into the supernatant, providing valuable insight for future research in metabolic engineering and efficient production systems in B. subtilis.