Progress In Microbes & Molecular Biology

Probiotic Modulation of the Skin Microbiome: Emerging Therapeutic Strategies in Dermatology

Mon, 12 Oct 2026 00:00:00 +0800

The skin microbiome is a dynamic microbial ecosystem that plays a fundamental role in maintaining epidermal barrier integrity, regulating immune homeostasis, and protecting against pathogenic colonisation. Dysbiosis of the skin microbiota has been implicated in numerous dermatological disorders, including acne vulgaris, atopic dermatitis, psoriasis, rosacea, and premature skin ageing, highlighting the microbiome as an emerging therapeutic target. In this context, probiotics have attracted increasing attention as microbiome-based interventions owing to their ability to restore microbial equilibrium and modulate host-microbe interactions. This review critically evaluates the current understanding of probiotics in dermatology, with particular emphasis on the molecular mechanisms underlying their therapeutic effects. Recent studies demonstrate that probiotics exert strain-specific activities through competitive exclusion of pathogens, production of antimicrobial peptides and bioactive metabolites, modulation of Toll-like receptor (TLR)-mediated signalling, regulation of nuclear factor kappa B (NFκB) and mitogen-activated protein kinase (MAPK) pathways, enhancement of tight junction proteins and ceramide synthesis, and modulation of cytokine networks involved in cutaneous immunity. Representative probiotic strains, including Lacticaseibacillus rhamnosus GG, Lactobacillus acidophilus, Lactobacillus plantarum, Bifidobacterium species, Bacillus coagulans, Saccharomyces boulardii, and Enterococcus faecium, are discussed with respect to their strain-specific molecular effectors and dermatological applications. Clinical evidence supporting oral and topical probiotic interventions is critically appraised, highlighting both therapeutic potential and the heterogeneity of existing studies. Emerging advances in postbiotics, engineered probiotics, synthetic biology, CRISPR-based microbiome editing, multi-omics technologies, and artificial intelligence-driven precision microbiome medicine are also discussed as future directions. Despite encouraging findings, important challenges remain, including strain standardisation, formulation stability, regulatory harmonisation, and the need for robust multicentre clinical trials. Collectively, current evidence suggests that probiotics represent promising adjunctive strategies for microbiome-targeted dermatological therapy; however, further molecular and translational investigations are required to facilitate their integration into scientifically validated precision dermatology.

Microbial Siderophores in Sustainable Agriculture: Molecular Insights, Smart Delivery Systems, and Biotechnological Applications

Mon, 04 May 2026 00:00:00 +0800

Microbial siderophores are low-molecular-weight compounds with a strong affinity for ferric (FSe³⁺) ions. They play a pivotal role in plant-microbial interactions by enhancing iron bioavailability to plants, primarily through the chelation and mobilization of iron under iron-limited conditions. Their versatile and multifunctional nature has positioned them as promising agents for sustainable and eco-friendly agriculture. However, the practical application of siderophore-based systems is constrained by challenges related to stability, bioavailability, environmental degradation, and large-scale production. This review examines recent advancements in siderophore-mediated agricultural practices and applications, with a focus on formulation strategies and delivery systems, including seed coatings, foliar sprays, and nanoparticle-based encapsulation approaches. The review further highlights key technological innovations integrating nanotechnology, microbiology, and artificial intelligence (AI) for precision agriculture. Particular emphasis is placed on controlled-release systems, production scalability, and field-level applicability. Existing knowledge gaps, particularly in large-scale production and commercialization, are discussed alongside future prospects involving synthetic biology and engineered microbial systems. Siderophore-based technologies represent a transformative approach toward enhancing soil health, crop productivity, and sustainable bioeconomy development.

Molecular Mechanisms of Melanogenesis in Hyperpigmentation: From Signaling Pathways to Nanocarrier-Based Therapeutic Strategies

Thu, 03 Sep 2026 00:00:00 +0800

Hyperpigmentation remains a complex dermatological challenge, often resistant to conventional topical therapies due to the skin’s inherent barrier function and the chemical instability of active depigmenting agents. Traditional formulations of depigmentation agents frequently suffer from poor dermal penetration and dose-dependent toxicity, leading to localized irritation and high relapse rates. This review highlights the transformative role of cosmeceutical nanotechnology in overcoming these limitations through advanced delivery systems, including lipid-based nanocarriers, polymeric nanoparticles, and microbiota-derived metabolite platforms. These nanosystems enhance the stability, controlled release, and targeted delivery of active compounds to melanocytes within the basal epidermis while modulating key molecular pathways involved in melanogenesis. Their mechanisms include inhibition of tyrosinase activity through active-site copper chelation, suppression of microphthalmia-associated transcription factor (MITF) signaling, and disruption of melanosome transport and transfer to keratinocytes. Emerging microbiota-based approaches further contribute by regulating oxidative stress, inflammation, and pigmentation while helping maintain skin homeostasis. Experimental and clinical evidence demonstrates that nanocosmeceutical formulations significantly improve depigmenting efficacy. Despite these advantages, challenges remain regarding nanotoxicity, long-term safety, large-scale manufacturing, and the lack of harmonized regulatory frameworks governing nanocosmeceuticals. As demand for effective and minimally invasive skincare continues to grow, nanotechnology provides a promising strategy for developing safer, more stable, and highly bioavailable therapies for hyperpigmentation. Continued research, standardized safety evaluation, and clearer regulatory guidelines are essential to facilitate the successful clinical translation and commercialization of nanotechnology-based depigmenting formulations.

Glycerol extract of Water hyacinth (Eichhornia crassipes (Mart.) Solms) attenuates hydrogen peroxide (H2O2)-induced cell death in HT22 hippocampal neurons

Wed, 30 Sep 2026 00:00:00 +0800

Neurological disorders continue to represent a significant global health burden, ranking among the leading causes of mortality and long-term disability. The persistent lack of effective therapeutic interventions reflects an incomplete understanding of the complex molecular mechanisms underlying neuronal cell death in the diseased brain. Among these, oxidative stress has been identified as a critical secondary injury mechanism that exacerbates neuronal damage. Recently, Eichhornia crassipes (Mart.), commonly known as water hyacinth, has emerged as a promising source of bioactive compounds with notable anti-inflammatory and antioxidant properties, making it a potential candidate for the development of neuroprotective therapies. This study aimed to assess the neuroprotective potential of E. crassipes extracts (ultrasound-assisted maceration), with glycerol extract (GE) emerging as the most effective extract, using a cell-based model of oxidative stress-induced by hydrogen peroxide (H₂O₂) in hippocampal HT22 cells. Cell viability of HT22 cells were measured through MTT assay, in order to determine cytotoxicity of extracts (0.5 mg/ml – 5 mg/ml) and protective effects of the extracts against H₂O₂ (via co-treatment assay). Our study revealed that H₂O₂ was able to induce cell viability loss in HT22 cells in a dose-dependent manner, and the IC₅₀ value of H₂O₂was determined as approximately 655.3 µM. Following the co-treatment assay, GE at 0.8 mg/ml displayed a significant protective effect by alleviating H₂O₂(700 µM)-induced cell death as compared to the H₂O₂alone group (67.4 ± 4.4% viability vs. 52.4 ± 1.4%, p < 0.05), while aqueous and mixed extracts did not display significant protective trend. These preliminary findings suggest that glycerol-based E. crassipes extract possesses underexplored neuroprotective potential against H₂O₂-induced oxidative stress in neuronal cells, though further mechanistic and in vivo investigation are required to validate these effects and establish translation relevance.

Phylogenomics, antimicrobial resistance, and mobile genetic elements in clinical Clostridioides difficile isolates from Hong Kong, China

Fri, 07 Aug 2026 00:00:00 +0800

Whole-genome sequencing enables high-resolution characterisation of the evolutionary and accessory-genome diversity of Clostridioides difficile beyond conventional sequence typing. We analysed 118 clinical C. difficile genomes from Hong Kong using recombination-filtered phylogenomics, pangenome analysis, antimicrobial-resistance and virulence screening, mobile-element context analysis and functional annotation. The population comprised 24 sequence types and formed distinct phylogenetic clusters that were broadly consistent with multilocus sequence typing assignments. Pangenome analysis identified 9,140 gene clusters and supported an open pangenome structure, indicating ongoing gene acquisition and loss within the population. Accessory-genome divergence increased with core-genome SNP distance (Spearman's ρ = 0.437, p < 1 × 10^-5), although some closely related isolates retained substantial differences in gene content, suggesting recent accessory-genome turnover. Antimicrobial resistance determinants showed stronger associations with mobile genetic elements (MGE) than with virulence-associated loci. In particular, erm(B), AAC/APH-family genes and tet(M) were frequently detected and commonly linked to insertion-sequence- or transposon-associated contexts, whereas major toxin loci showed limited evidence of local mobility. Functional annotation revealed broadly conserved functional profiles dominated by transcription-, metabolism-, and signal transduction-related categories, alongside significant sequence type-associated variation in KEGG pathway composition (PERMANOVA R² = 0.434, p = 0.001), with ST54 forming a distinct functional cluster. Collectively, these findings demonstrate that this Hong Kong C. difficile population is structured by stable evolutionary lineages while maintaining extensive accessory-genome diversity, and highlight the prominent role of MGE in shaping antimicrobial-resistance architecture relative to the largely conserved virulence repertoire.

Pangenomics and Comparative Biosynthetic Diversity of Malaysian Mangrove-Derived Streptomyces albidoflavus MUM256 among S. albidoflavus-Assigned Genomes

Wed, 07 Oct 2026 00:00:00 +0800

Streptomyces sp. MUM256, isolated from Malaysian mangrove soil, has previously shown antioxidant and selective anticancer activities, including induction of cell-cycle arrest and apoptosis in colon cancer cells. However, its precise taxonomic position and biosynthetic potential remained unresolved at the whole-genome and population levels. Here, we sequenced a high-quality long-read genome of MUM256 and integrated genome-based taxonomy, pangenomics and comparative biosynthetic gene cluster (BGC) analysis. The final assembly comprised a single 6.89-Mb contig with 73.4% G+C content, 98.5% BUSCO completeness and 5,897 predicted protein-coding sequences. Genome-based analyses consistently assigned MUM256 to Streptomyces albidoflavus, with NRRL B-1271 identified as its closest GTDB-Tk placement reference. A quality-filtered cohort of 151 genomes revealed an open pangenome comprising 21,082 gene clusters, including 2,684 strict-core clusters, with continued gene-family accumulation supported by Heaps' law modelling (γ = 0.307). Population-scale genome mining of 119 quality-filtered genomes identified 2,651 BGC records grouped into 178 gene cluster families (GCFs), of which 84.3% were rare or singleton. MUM256 contained 18 predicted BGCs representing 18 GCFs, all shared with other members of the analysed S. albidoflavus-assigned genomes. Comparative analysis of fredericamycin A-like and SF2768-like loci further revealed population-level variation in BGC prevalence and architecture. Together, these findings establish MUM256 as S. albidoflavus and provide a population-genomic framework for prioritising biosynthetic loci for future metabolomic and functional validation.

Early colonization by Enterobacteriaceae in the developing gut microbiota of preterm infants: A culture-based insight

Fri, 15 May 2026 00:00:00 +0800

The gut microbiome plays a significant role in human health and disease pathogenesis. In preterm infants, gut dysbiosis often results in early dominance of opportunistic pathogens, particularly members of the Enterobacteriaceae family. Enterobacteriaceae can serve as potential reservoirs of opportunistic pathogens, antibiotic-resistance determinants and may contribute to major neonatal morbidities, including necrotizing enterocolitis (NEC) and late-onset sepsis (LOS). This study aims to isolate and identify Enterobacteriaceae, as well as to explore the diversity of isolated Klebsiella pneumoniae from meconium/early stool samples of preterm infants collected from a neonatal intensive care unit (NICU) in Johor Bahru, Malaysia. A combination of culture-based isolation technique, phenotypic and genotypic identification methods was used to identify the culturable Enterobacteriaceae in the gut of preterm infants. Three main bacterial families were successfully isolated and identified from the stool samples of preterm infants, which include Enterobacteriaceae, 46% (76/166 isolates), Staphylococcaceae, 22% (37/166), Enterococcaceae, 22% (37/166) and others, 10% (16/166). It was clear that Enterobacteriaceae was one of the predominant bacterial groups during the early gut colonization in preterm infants, making up to 46% of all isolates. Within the Enterobacteriaceae family, K. pneumoniae, 74% (56/76 isolates) dominates, followed by Escherichia coli, 15% (11/76), Klebsiella aerogenes, 9% (7/76), Citrobacter europaeus, 1% (1/76), and Citrobacter freundii, 1% (1/76). The high number of Enterobacteriaceae isolates, particularly K. pneumoniae, followed by E. coli are concerning as these bacterial species are often associated with hospital-acquired infections in the NICU. Our findings provide insight into the early gut colonization patterns of culturable gut bacteria in preterm infants. It highlights the importance of continuous microbiological monitoring and infection control measures within the NICU to mitigate potential Enterobacteriaceae-associated infections.

Molecular Mechanisms Linking E‑cigarette Exposure to Cancer Metastatic Behaviour: Focus on Epithelial-to-Mesenchymal Transition and Inflammation: A Systematic Review

Thu, 15 Oct 2026 00:00:00 +0800

Electronic cigarette use has been mushrooming globally in recent years, with an estimated 82 million vapers worldwide, including 14.3 million in Southeast Asia. Although e-cigarettes are generally considered a safer alternative to traditional cigarettes, their long-term health effects, particularly on cancer progression and metastasis, remain uncertain. This systematic review evaluated the existing literature to determine whether e-cigarette exposure influences cancer cell metastatic behaviour. A systematic search was conducted using predefined terms in MEDLINE, PubMed, and Web of Science from database inception to 1^st May 2025. The studies must be primary research and investigate the effects of e-cigarette exposure on cancer cell metastasis. Seven eligible studies were selected, assessed for reliability using the SciRAP tool, and synthesised manually. The literature evaluated several aspects of cancer metastasis, including cell invasion, migration and motility, morphological changes, tumour area, growth, proliferation, colonisation or localisation, cell viability, and immunological changes. Evidence synthesis suggests that e-cigarette exposure may promote cancer cell migration; however, these findings are constrained by the small number of studies, methodological limitations, and lack of long-term investigations. Reported effects varied depending on cancer cell type, nicotine presence, and e-liquid flavouring. Current preclinical data indicate e-cigarette exposure may promote cancer metastatic behaviour through epithelial-to-mesenchymal transition (EMT) induction (E-cadherin loss, vimentin upregulation), RAGE-mediated inflammatory signalling, and CCL5/CCR5-dependent monocyte recruitment. However, all seven included studies were rated “not reliable” by SciRAP (methodological quality scores 47–70%), rendering evidence preliminary. Future studies require physiologically relevant direct aerosol exposure systems, cigarette smoke comparators for relative risk assessment, diverse cancer models, and longitudinal clinical investigations to establish the true impact of vaping on cancer metastasis.