Bacteriophages (phages) are the most abundant biological entities on Earth. Within the human microbiome, they vastly outnumber eukaryotic viruses and commensal bacteria, serving as essential regulators of microecological balance. Traditionally viewed strictly as bacterial predators, phages are now known to form direct, bidirectional interaction networks with mammalian cells. Beyond indirectly affecting human health by altering bacterial communities, phages actively cross biological barriers to engage in direct crosstalk with immune cells and trigger specific immunological effects. This phage-mediated immunity encompasses receptor recognition, endocytic trafficking, and the modulation of intracellular signaling pathways. This review summarizes current progress in phage immunity by examining direct phage-mammalian cell interactions. We specifically focus on how phage structural characteristics dictate their internalization, intracellular localization, and subsequent immune regulation. Furthermore, we discuss the practical implications of phage immunity across various conditions, including inflammatory bowel disease, chronic infections, systemic disorders, and emerging applications in cancer immunotherapy. Ultimately, this review aims to clarify the molecular and material basis of phage immunity, providing a theoretical foundation for understanding the cross-kingdom regulation effects of phages and the development of phage-based immunotherapies.

To enhance the transcriptional strength of the inducible promoter P_malA and achieve efficient extracellular expression of target proteins, in this study, error-prone PCR was employed to construct a promoter mutant library based on a previously established maltose-inducible expression system (MATE expression system). Using green fluorescent protein (GFP) as a reporter protein, a high-expression mutant designated as M3, harboring a single-base substitution in the-35 region, was identified. The mutant promoter M3 was then utilized as a regulatory element to construct a recombinant expression vector for glucose-6-phosphate isomerase (phospho-glucose isomerase, Pgi), which was fused at its N-terminus to the Sec-type signal peptide AmyS to facilitate secretion. To further optimize inducible expression, various carbon sources were evaluated, and the optimal condition was applied in a 3-L bioreactor for high-density fermentation, yielding a maximum Pgi titer of 7.26 g/L. Functional assays confirmed that the catalytic activity of Pgi expressed in this system was comparable to that of the control produced in Escherichia coli, indicating that enhanced expression did not compromise protein functionality. This study establishes an optimized and efficient MATEbased expression system, offering a feasible strategy for high-level expression of key enzymes in metabolic engineering and supporting the application of Bacillus subtilis in the development of industrial enzyme preparations.

Inner Mongolia Alxa white cashmere goat milk and its dairy products with rich nutritional value and outstanding health care functions, serve as a vital source of dairy for local herders, but few studies related to the diversity of fungi that play a probiotic role have been reported. Therefore, in this study, Illumina-Miseq sequencing technology was used to determine the fungal ITS gene sequences in white cashmere goat milk, bishylag and airiga, and the comparison of fungal community structure and diversity were conducted. The results showed that the Shannon index of fungi in white cashmere goat milk and bishylag was significantly higher than that in airiga (P<0.05), while the Simpson index was significantly lower (P<0.05). However, there was no significant difference (P>0.05) between the Shannon and Simpson indices of the fungi in white cashmere goat milk and bishylag. Additionally, no significant differences were found in the Ace and Chao indices among white cashmere goat milk, bishylag and airiga (P>0.05). Beta diversity analysis revealed a high similarity in fungal community composition between white cashmere goat milk and bishylag, whereas the fungal community structure of airiga was distinct from that of white cashmere goat milk and bishylag. The dominant fungal phyla in white cashmere goat milk, bishylag and airiga were Ascomycota and Basidiomycota. At the genus level, the dominant fungi were Apiotrichum, Cutaneotrichosporon, Cladosporium and Alternaria in white cashmere goat milk; Apiotrichum, Cutaneotrichosporon and Filobasidium in bishylag; and Issatchenkia, Rhodotorula, Kazachstania and Pichia in airiga. The relative abundance of fungal metabolism-relatde enzymes in white cashmere goat milk and its dairy products was higher for glucan 1, 4-alpha-glucosidase, adenosine triphosphatase, DNA-directed RNA polymerase, exo-alpha-sialidase, and peptidylprolyl isomerase. FUNGuild functional prediction indicated that saprotrophic fungi were the main nutritional mode in white cashmere goat milk and its dairy products. These findings not only establish a comprehensive understanding of fungal diversity in white cashmere goat milk and its dairy products in Alxa, Inner Mongolia, but also provide a basis for the study and safety evaluation of fungi in white cashmere goat milk and its dairy products.

Floridoside, a glycosyl alcohol exhibiting diverse biological activities including antioxidant effects, immune regulation, and protein stabilization, demonstrates significant potential for applications in the food and cosmetic industries. In our previous study, we successfully achieved the heterologous expression of the recombinant α-galactosidase rAgaAJB07 from Mesorhizobium, which catalyzes floridoside biosynthesis via trans-glycosylation was obtained. In order to improve floridoside production, the reaction conditions were systematically optimized for the recombinant enzyme using glycerol as the acceptor substrate and p-nitrophenyl α-D-galactopyranoside (pNPG) as the donor substrate. The optimal parameters were determined as follows: 500 mmol/L glycerol, 40 mmol/L pNPG, 1.5 U/mL enzyme concentration, 2 h reaction duration, pH 8.5, and 30 ℃. Under these conditions, recombinant rAgaAJB07 achieved a maximum floridoside yield with a 66.2% enhancement compared to baseline parameters, while simultaneously reducing the reaction time by 22 hours. This optimization strategy provides a robust methodological framework for scalable enzymatic synthesis of floridoside.

The cytoskeleton could regulate the fusion and division of mitochondria, meanwhile, mitochondria also could regulate the normal dynamics of the cytoskeleton. The mpc1 gene encodes mitochondrial pyruvate carrier 1 which is located in the mitochondrial membrane. The protein of MPC1 is an essential component of the mitochondrial pyruvate carrier complexes. Currently, the effect of mpc1 gene deletion on the dynamics of spindle, histone, and actin has not been reported. In this study, fluorescent labels of microtubules, histone, and actin were constructed in Schizosaccharomyces pombe cells. The stability of cell dynamics at different stages was observed using live-cell imaging to investigate the effects of mpc1 gene deletion on actin. Compared with the wild-type strain, the results showed that the mpc1Δ strain reduced the spindle elongation time by 6.70 min (P<0.01), accelerated the elongation rate by 0.17μm/min (P<0.01), reduced the chromosome segregation time by 3.40 min (P<0.01), and prolonged the total time for actin ring aggregation and contraction by 3.80 min (P<0.01) at room temperature. The experimental results mentioned above indicated that although the deletion of mpc1 gene promoted spindle elongation and chromosome segregation, it slowed down the formation and contraction of actin rings, ultimately leading to slow cell growth. This study provided a basis for further investigation of mpc1 function.

G protein-coupled receptors (GPCRs) in pathogenic fungi have become one of the critical targets for controlling pathogenic disease. In this study, 36 candidate GPCRs were identified from Penicillium expansum by bioinformatics approaches including three transmembrane prediction tools (DeepTMHMM, Phobius, and TOPCONS) and four GPCR prediction platforms (GPCRHMM, GPCRPipe, GPCR-Pen, and GPCRPred). The topological structure analysis, subcellular localization, and functional annotation demonstrated the reliability of the prediction strategy. Phylogenetic classification revealed that these candidate GPCRs were distributed across six distinct fungal GPCR classes, which are characterized by conserved domains such as fungal rhodopsin-like receptor families, pheromone mating factor STE2, pheromone A receptor STE3, and RTA1-like proteins. Physicochemical property analysis demonstrated that the candidate GPCRs predominantly exhibit neutral or alkaline proteins, with 44.44% classified as unstable proteins and 97.22% showing hydrophobic properties. These findings provide a critical theoretical foundation for elucidating the biological functions, signaling mechanisms, and pathogenic roles of GPCRs in P.expansum, and also highlighting potential targets for the development of novel antifungal molecules.

This study conducted a comparative investigation on wild (MT) and cultivated (ZT) Schisandra chinensis in northern China. Utilizing high-throughput sequencing technology to analyze the rhizosphere soil microbial community structure and potential functional microbiota. This was integrated with the quantification of the primary medicinal component, lignans, and the determination of soil physicochemical properties, including total phosphorus (TP), total potassium (TK), total nitrogen (TN), total organic carbon (TOC), and soil organic matter (Som). The research aimed to elucidate the interrelationships among lignan content, rhizosphere microorganisms, and soil properties, thereby providing theoretical insights into the metabolic mechanisms of lignans in S.chinensis and enhancing the medicinal value of cultivated varieties. The results demonstrated that wild samples exhibited significantly higher lignan content than cultivated samples, with schizandrin, schisantherin A, and γ-schizandrin concentrations nearly double in wild samples. The rhizosphere soil of wild samples showed substantially higher nutrient levels, with TK, TP, TN, and Som contents approximately 1.5, 2.6, 7, and 9 times greater than those in cultivated samples, respectively. The abundance of nitrogen significantly increased the relative abundance of RB41 and Gaiella, while elevated soil organic matter promoted the enrichment of Mycobacterium. These three microbial groups showed positive correlations with lignan content, potentially explaining the superior lignan accumulation in wild samples. Furthermore, Fusarium, Neonectria, Trichocladium, and Mortierella demonstrated positive correlations with lignan content. Soil moisture content showed a significant positive correlation with lignan accumulation, as did TP, TK, TN, and Som. Notably, soil pH emergedas a crucial factor influencing the rhizosphere microbial community, exhibiting a significant negative correlation with lignan content.

This study aimed to prepare monoclonal antibodies against human β2-MG and to establish rapid and accurate quantitative and qualitative immunoassay methods for β2-MG detection. Recombinant β2-MG was produced through prokaryotic expression and purification, and subsequently used for immunizing BALB/c mice. Monoclonal antibodies against human β2-MG were generated using hybridoma technology and screened via double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), which facilitated the development of a chemiluminescence enzyme immunoassay (CLEIA). Clinical serum β2-MG levels were measured to evaluate and analyze the detection performance of the proposed CLEIA. Additionally, a convenient and rapid colloidal gold immunochromatographic assay for β2-MG detection was preliminarily established. The monoclonal antibody pair 5H7/6H9-AP was developed into the CLEIA, demonstrating a linear range of 0.14-120.00 μg/L (extended to 60.00 mg/L). The serum β2-MG CLEIA results showed excellent correlation with the latex enhanced immunoturbidimetry assay conducted in hospitals (R²: 0.96, P<0.000 1). The established colloidal gold immunochromatographic assay exhibited good sensitivity for detecting recombinant β2-MG, with test strips capable of detecting a minimum concentration of 0.20 mg/L. The prepared monoclonal antibodies for β2-MG, along with the established quantitative and qualitative immunoassay methods, hold significant potential for clinical diagnostic applications.

Steroids are the second-largest category of clinical drugs following antibiotics, with significant physiological functions such as anti-inflammatory, antiviral, antitumor, and antihypertensive effects, bearing a huge market demand. Currently, the mainstream industrial approach for steroid drugs production is microbial semi-synthesis, which involves microbial degradation of phytosterols into steroid-drug intermediates (precursors) followed by chemical modification. This review focuses on Mycobacterium sp., a representative strain used for synthesizing steroid-drug intermediates, and outlines the key steps in its steroid metabolic pathway, including sterol uptake, initial oxidation of sterol nucleus, side chain degradation, further oxidation of sterol nucleus, and nucleus cleavage, along with the key enzymes involved. Furthermore, the genetic modification systems of gene overexpression, knockout and knockdown applicable to Mycobacterium are summarized. However, the identification and characterization of complex enzyme systems in the degradation process of sterol side chain remains a major challenge in current research and a key bottleneck restricting the development of novel steroid-drug intermediates. Therefore, accelerating the analysis of sterol metabolic pathways by high-throughput sequencing, bioinformatics analysis and site-directed saturation mutagenesis is essential for the rational design of mycobacterial cell factories and for the construction of strains with high-yield of new steroid intermediates.

Long-term excessive application of chemical fertilizers in agricultural production has led to soil quality degradation and environmental problems, which to some extent restricts the green development of modern agriculture. Microbial fertilizers can enhance crop yield and quality, improve stress resistance, and reduce environmental pollution. This paper provides an overview of the characteristics, development history, and classification of microbial fertilizers, with a focus on elucidating their mechanisms which include regulating plant hormones (such as salicylic acid and auxin) to influence plant immunity and development, improving soil aggregation through physical entanglement and secretion of extracellular polymers, as well as activating soil nutrients by secreting siderophores, solubilizing phosphates, and participating in nitrogen fixation and nitrification processes. The application prospects and trends in technology development of microbial fertilizers are analyzed and summarized from macro, market, and technical perspectives. Considering the agricultural context of Liaoning Province as a major grain-producing region, the current status and regional advantages of microbial fertilizer development in Liaoning are examined. Finally, future development directions for China's microbial fertilizer industry are discussed, aiming to provide references for the research and application of microbial fertilizers.

Polycyclic aromatic hydrocarbons (PAHs), as a typical class of organic pollutants, are difficult to naturally degrade in the environment. However, microorganisms, by virtue of their environmental adaptability, play an irreplaceable role in the degradation process of PAHs. Therefore, the development of efficient laboratory isolation and cultivation techniques for PAHs-degrading microorganisms has become a research direction. This article reviews the types of PAHs-degrading microorganisms, as well as their cultivation techniques and methods. It points out the different mechanisms of microbial degradation of polycyclic aromatic hydrocarbons, including bacteria, fungi, algae (specifically microalage belonging to the category of microorganisms), and actinomycetes, etc., and their metabolic pathways for degrading PAHs under aerobic or anaerobic conditions. Additionally, it discusses different types of traditional and novel cultivation techniques, and makes a comparative analysis of the characteristics and applications of traditional cultivation techniques (such as optimizing the composition of the culture medium and adjusting the structure of the culture medium, etc.) and novel cultivation techniques (such as cell sorting technology, etc.). This is helpful for screening more effective cultivation methods, exploring more PAHs-degrading microorganisms, further promoting the research on polycyclic aromatic hydrocarbon-degrading microorganisms, and providing theoretical basis and technical support for solving the problem of PAHs pollution.

The comprehensive experimental course of microbial engineering is one of the core courses of the National Characteristic Major and the National First-class Undergraduate Major in biotechnology. The course content is closely integrated with the needs of national and local industries, based on practical production and scientific problems, and consists of eight comprehensive research-based experimental projects. The teaching process is principally based on students' independent experimentation, supplemented by teacher guidance, and implemented in six stages:pre-class mobilization, plan formulation and demonstration, independent experimentation and process management, experiment summary and analysis, report writing, and academic evaluation. The course places emphasis on cultivating students' program design ability, comprehensive practical ability, problem analysis ability, and other pertinent skills. It fosters an environment characterized by cooperative learning, joint exploration, and mutual assistance, thereby enhancing students' comprehensive practical innovation ability and their capacity to address complex engineering challenges. The teaching reform of the course has achieved marked effect, laying an important foundation for the teaching reform and innovation of comprehensive research-based experimental courses. The objective of this initiative is to serve as a valuable reference point for colleagues engaged in the instruction of associated course offerings. This objective is to be realized through the development and enhancement of a novel, integrated experimental curriculum in microbial engineering.