Current Microbiology最新文献

Microbially induced calcium carbonate precipitation (MICP) holds promise for sandy soil stabilization, but requires environmentally adaptable urease-producing bacteria. This study isolated a urease-producing strain, NM01 (Lysinibacillus fusiformis), from a local carbonate mining area. NM01 demonstrated robust growth and high urease activity (~ 30 mM/min) across a broad temperature (25-35 °C) and pH (6-10) range. Sand column cementation tests confirmed NM01's efficacy, transforming loose sand into cohesive structures. The unconfined compressive strength (UCS) significantly increased from 0 to 630 ± 50 kPa, while calcium carbonate content rose from 3.81% to 8.99%. Comprehensive characterization using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) verified successful calcium carbonate precipitation and biologically mediated sand solidification. XRD and SEM analyses identified the precipitated calcium carbonate primarily as calcite and vaterite. The successful isolation of this locally adapted, high-performance ureolytic bacterium provides a valuable microbial resource for advancing MICP technology applications.

A long-rod-shaped, Gram-reaction-negative, non-motile, strictly aerobic, pale-gray-colored alphaproteobacterium, designated KMU-117^T, was isolated from a seawater sample taken in the Republic of Korea and analyzed. Strain KMU-117^T was capable of growing at 20-37 °C, at pH 5.5-9.0, and at 0-3.0% (w/v) NaCl. Phylogenetic comparison of the 16S rRNA gene sequences revealed that strain KMU-117^T was placed in the family Roseobacteraceae and showed greatest similarity (95.7%) with Palleronia rufa MOLA 401^T. Strain KMU-117^T contained C_18:1 ω7c, anteiso-C_15:0, and C_16:0 as the major fatty acids (> 10%) and Q-10 as a sole quinone. The polar lipids of KMU-117^T included phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, and four unidentified polar lipids. Strain KMU-117^T had a 3.8 Mb genome with a 67.0% G + C content. The genome-based analysis of ANI and AAI values between strain KMU-117^T and closely related species of the family Roseobacteraceae were 71.5-74.0% and 66.8-69.5%, respectively. In silico DDH value between strain KMU-117^T and P. rufa MOLA 401^T was 18.8%. Consequently, the phenotypic and phylogenomic data analyzed in this study suggest that the strain KMU-117^T belongs to a novel genus and a new species of the family Roseobacteraceae, for which the name Saliniferula longa gen. nov., sp. nov. is proposed. The type strain is KMU-117^T (= KCCM 90342^T = NBRC 117094^T).

Seasonal fluctuations in diet and climate shape animal gut microbiota, especially those living in extreme climatic conditions. Yet their role in facilitating primate adaptation to high-altitude remains unclear. This study investigates the seasonal dynamics in gut microbiome of wild rhesus macaques (Macaca mulatta) from high altitude (over 3,000 m) in Yajiang couke. We collected 117 fecal samples across four seasons and analyzed using 16S rRNA high-throughput sequencing combined with predictive functional metagenomics. We observed clear seasonal shifts in gut microbial diversity and composition. High α-diversity in autumn and winter reflected increased dietary diversity during these periods. Firmicutes predominated in summer, while Bacteroidota increased during winter. LEfSe analysis revealed seasonal specific taxa: UCG-005, Christensenellaceae R-7, and Prevotella_9 were dominated in winter but declined in summer and spring, whereas Blautia peaked during summer and decreased toward winter. Redundancy analysis showed that temperature, humidity, and precipitation were positively associated with Blautia and Sarcina, but negatively with Monoglobus and Helicobacter, underscoring the strong influence of climatic variables on gut community structure. Functional predictions revealed seasonal differences in gut microbiota related to energy metabolism (spring), glycan biosynthesis (summer), membrane transport (autumn), and environmental adaptation (winter) indicating microbial contributions to host adaptation under fluctuating climatic conditions. These findings demonstrate that gut microbiome of high-altitude macaques is highly responsive to changes in seasonal diet and climate. By integrating microbiome dynamics with climatic drivers, our study provides new insights into host-microbe-environment interactions and advances our understanding of primate adaptation under extreme climatic conditions.

A Gram-reaction-positive, non-spore-forming actinomycete strain was isolated from lava tunnel in Jeju, Republic of Korea, and its taxonomic associations were examined by a polyphasic approach. The novel strain, designated YC2-6^T was found to grow at 10-30 °C, pH 5.0-10.0 and 0-2% (w/v) NaCl. The 16S rRNA gene phylogeny showed that strain YC2-6^T formed a distinct subline apart from the genus Antrihabitans The morphological characteristics were in line with most of the genus Antrihabitans, in that cells showed a rod-coccus life cycle during growth, but did not produce any mycelium unlike recently described Antrihabitans spumae. The chemotaxonomic traits such as diamino acid and sugars in cell wall with N-glycolylated murein were typical for the genus Antrihabitans. Moreover, strain YC2-6^T also had the major menaquinone of MK-8(H₄, ω-cycl), the predominant fatty acids of C_16:0, summed feature 3 (C_16:1ω6c and/or C_16:1ω6c; 20.2%) and C_18:1ω9c, and phosphatidylethanolamine as the diagnostic polar lipid, which were in agreement with those of the Antrihabitans stalactiti, as the type species of the genus. In addition, strain YC2-6^T also contained C_16:0 N alchol as an additional fatty acid. The core genome-based phylogeny revealed that strain YC2-6^T formed a highly supported clade with the type strain of Antrihabitans stalactiti. The average amino acid identity values with members of the Antrihabitans were ≥ 72.1%. The highest average nucleotide identity and digital DNA-DNA hybridisation values were 75.7% and 20.4%, respectively, with the phylogenomically closest relative, Antrihabitans stalactiti, indicating that strain YC2-6^T (= KACC 19821^T = DSM 108745^T) represents a new species of the genus Antrihabitans, for which the name Antrihabitans aurantiacus sp. nov. is proposed.

Chimeric antigen receptor (CAR)-based immunotherapies face significant translational challenges in solid tumor applications, particularly regarding manufacturing scalability, tumor targeting specificity, and antigen heterogeneity. This systematic review evaluates microbial systems as innovative platforms to address these limitations through synthetic biology-driven approaches, with a focus on bridging preclinical advances to clinical implementation. Analysis of 389 peer-reviewed studies (2015-2025) reveals that engineered probiotic strains (e.g., Escherichia coli Nissle 1917) achieve selective tumor colonization while functioning as programmable factories for:1. Synthetic antigen production and single-chain variable fragment (scFv) expression,2. Costimulatory domain delivery enabling antigen-agnostic CAR-T activation,3. Tumor microenvironment modulation via immunostimulatory chemokines. Microbial platforms demonstrate superior manufacturing economics (70-90% cost reduction vs. conventional methods) and enhance CAR-T functionality through epigenetic reprogramming by microbial metabolites (e.g., short-chain fatty acids). CRISPR/Cas-engineered genetic circuits further enable precise spatiotemporal control of therapeutic payloads.Microbial systems represent transformative platforms for scalable, programmable CAR immunotherapy with significant potential for solid tumor targeting. Key barriers to clinical translation include biocontainment challenges, incomplete mechanistic understanding of tumor homing specificity, and safety validation requirements. Strategic integration of synthetic biology with microbial chassis offers a viable pathway toward accessible next-generation cancer therapies.

Talaromyces marneffei (TM), an opportunistic pathogenic fungus, binds to CD86, which acts as a co-stimulatory molecule for CTLA4. CD86 activates CTLA4, which transmits inhibitory signals, yet its role in TM immune responses remains unclear. In this study, we investigated how the binding of TM to CD86 modulates the CD86-CTLA4 regulatory pathway. To establish the co-culture system of THP-1/THP-1-CD86-EGFP, TM, and Jurkat, Jurkat cells were first transfected with lentivirus to generate the target cell lines. The interactions among TM, CD86, and CTLA4 within this system were then investigated using confocal fluorescence microscopy. To evaluate changes in the expression levels of target factors, RT-qPCR and Western blotting were performed. Potential downregulated pathways were further identified through RNA sequencing (RNA-Seq) analysis. Additionally, the functional role of CTLA4 in the co-culture system was assessed by bactericidal assays. In the co-culture system, THP-1 macrophages engulfed TM, which bound to CD86 and formed immature phagosomes that subsequently escaped. Escaped TM interacted with Jurkat cells via CD86, activating CTLA4. Transcriptional levels of CD86 and CTLA4 initially increased and then decreased in the TM(+) vs. TM(-) comparison. After 24 h, OE showed significant differences in CD86 and CTLA4 (transcriptional and translational levels) vs. CON and NC, along with differences in IFN-γ, IL-5, and IL-13. At 48 h, CD86 and CTLA4 expression varied with THP-1/CD86-EGFP presence. RNA-seq showed TM proliferation and differentiation downregulated PI3K-Akt and T cell receptor pathways. The fungal killing assay indicated that CTLA4 may facilitate TM in evading immune-mediated damage. TM regulates the CD86-CTLA4 immune regulatory pathway by binding to the CD86 protein, thereby evading the immune killing of macrophages.

Polyhydroxyalkanoates (PHAs) are synthesized by microorganisms as cytoplasmic biopolymers in response to nutritional starvation. These biopolymers have diverse applications because of their non-toxic and biodegradable nature and can be an effective alternative to conventional petrochemical polymers as they offer similar qualities. For this purpose, PHA-producing bacterium LO1 was isolated from lubricating oil contaminated soil and identified as Bacillus subtilis (MK071733). Furthermore, LO1 was found to be the most prominent PHA accumulating strain on groundnut oil as carbon source under optimized growth conditions. The optimum growth conditions for PHA synthesis was pH 7, temperature 35 °C, incubation period 72 h, inoculum size 4%, (v/v), groundnut oil 2%, (v/v), and ammonium sulfate 1.5%, (w/v) in mineral salt medium (MSM). Under these optimized conditions, 5.52 g/L of PHA cell dry weight (CDW) was obtained from 9.8 g/L of bacterial dry cell weight (DCW) through two-stage shake flask cultivation. Further, extracted PHA was characterized via Fourier transform infrared spectroscopy (FT-IR) and Gas chromatography-mass spectrometry (GC-MS). These techniques confirmed the presence of mcl-PHA copolymers in the extracted polymer.