MicrobiologyOpen最新文献

Plasmids play an essential role in the spread of antimicrobial resistance (AMR) by facilitating the horizontal transfer of resistance genes between bacterial environments. However, large-scale investigations into the association between plasmid incompatibility groups (Inc groups) and specific resistance profiles remain limited. In this study, we analyzed 28,047 plasmid sequences from publicly available whole-genome sequencing data sets, identifying incompatibility groups in 11,288 plasmids using in silico replicon typing. Our results revealed that the majority of plasmids harbored a single replicon, while a substantial fraction carried multiple replicons, predominantly two. We evaluated the relationship between plasmid replicon spillovers and their role in the spread of resistance genes. Our results revealed that plasmids with five replicons have a significantly higher resistance potential (60%) compared to plasmids with fewer replicons, decreasing their adaptability and propensity for cointegration, which facilitates horizontal gene transfer. Among the resistance-associated plasmids, the IncF, IncI, and IncH families were predominant and acted as effective carriers of resistance genes. Comparative analyses between resistant and non-resistant plasmids did not reveal a clear visual pattern of association between the most prevalent Inc groups and specific antimicrobial classes, indicating that such relationships are shaped by contextual factors, including selective instructions, bacterial host diversity, and distribution. These findings highlight the complexity of the spread of plasmid-mediated AMR and highlight the need for integrated genomic and epidemiological approaches to better understand the ecological and evolutionary dynamics that influence the spread of resistance genes.

Tomatoes are produced worldwide, and in South Africa, they are cultivated in all provinces. The most destructive tomato diseases are bacterial spot, caused by Xanthomonas spp., and bacterial wilt caused by Ralstonia solanacearum. Over the years, different strategies have been employed to control tomato disease. The disadvantage of chemical pesticides is that they alter microbial communities and sometimes remain on food commodities. Recently, studies have been conducted on biological control agents in the hope of eventually replacing the use of chemical pesticides. Some studies have discovered potential biological control agents for bacterial diseases. Better insight into host-pathogen interaction will help develop better disease management strategies. This review provides insights into plant diseases caused by Ralstonia and Xanthomonas and how they are managed.

This study aimed to characterize the biofilm-forming microbial communities on clinically used dental elevators to assess their potential risks of cross-contamination and nosocomial infections resulting from percutaneous injuries in dental healthcare settings. Over a period of 3 consecutive weeks starting on August 1, 2024, biofilm samples were collected from the tips of 15 dental elevators used on the first five wisdom teeth extraction patients daily. Total DNA was extracted, and specific barcoded primers were synthesized to construct SMRTbell sequencing libraries, which were subsequently sequenced using the PacBio Sequel II platform. The sequencing generated 923,990 circular consensus sequences (CCS), with an average of 61,599 CCS per sample. Taxonomic annotation revealed a diverse microbial community dominated by genera such as Prevotella, Fusobacterium, Streptococcus, and Lactobacillus, alongside unclassified taxa from the Candidatus Saccharibacteria (TM7) group. Alpha and beta diversity analyses demonstrated significant variations in microbial composition across samples, highlighting the heterogeneity of biofilm formation, while strong positive correlations observed between specific bacterial genera, such as Bacillus and Paenibacillus, suggested potential co-colonization patterns. These findings underscore the complexity of microbial contamination on dental instruments and emphasize the need for improved sterilization protocols to mitigate infection risks. Consequently, this study provides valuable insights into the microbiological safety of dental practices and highlights the utility of third-generation sequencing in advancing infection control strategies.

The objective of this study was to evaluate the temporal stability and object-to-skin transferability of the skin virome in a Korean population. Skin virus metagenomes were collected from the anatomical locations (forehead, left hand, and right hand) of eight healthy adults and monitored over 3 months at intervals of 6 weeks. To assess the potential transfer of virome between skin and objects, subjects were instructed to contact four types of objects (cell phones, door handles, fabric, and plastic). Virome samples were then collected from the surfaces of these objects. Viruses were identified using databases and viral annotation bioinformatics tools. Fifteen viral families were consistently found to be stable and well-transmissible across anatomical locations and four types of objects. Furthermore, the presence/absence profiles of 54 viral species belonging to these 15 viral families exhibited significant individual specificity on both the skin (p < 0.01) and the objects handled by each subject (p < 0.05). We confirmed that these 54 viral markers remain stable over time within individuals and are transferable to contacted surfaces. Additionally, we explored the potential of using the virome as an individual identification marker, which may suggest new approaches for forensic applications.

Accumulation of synthetic plastics in the biosphere has led to global pollution, provoking serious consequences for the environment and human health. Uncontrolled agricultural plastic landfills have the risk of becoming a source of agrochemicals and microplastics. Biotechnological approaches to solve plastic pollution include the removal of these polymers through biological degradation, which is a friendly environmental method. The microbial communities colonizing plastic debris (plastisphere) are considered as a potential source of plastic-degrading microorganisms. In this study, a bacterial biodiversity analysis, based on 16S rRNA gene-targeted metagenomic sequencing, was achieved in the plastisphere of low-density polyethylene (LDPE) and polypropylene (PP) polymers from an agricultural landfill. The α-diversity analysis did not show significant differences between LDPE and PP plastispheres and the plastic-free bulk soil, while LDPE and PP bacterial communities clustered close, but separately from the bulk soil in a β-diversity analysis. Although the taxonomic composition of both plastispheres was different, they shared a significantly higher proportion of Cyanobacteria and Deinococcota than the bulk soil. Additional analyses showed different indicator families, genera and species that can be associated with plastispheres. A predictive functional analysis suggests that degradation of plastic additives in both plastispheres is probably occurring. In addition, the existence of degradation processes for specific herbicides in each plastisphere is highlighted, and the possible exposure of LDPE to both physical and biological degradation processes is also described. These results will contribute to characterize the soil plastisphere exposed to different environmental conditions, and to understand the specific biological niches where plastic-degrading microorganisms could survive.

The complexities of microbial detection and conventional enumeration necessitates the adoption of pragmatic alternatives. This review expands the boundaries of knowledge for microbial detection and sensing, particularly within the field of water quality analysis. Observed alternatives to conventional techniques for microbial analyses in recent studies include Microarray, Fluorescent in situ hybridization (FISH), loop-mediated isothermal amplification (LAMP), matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and flow cytometry, while nanosensors stood out as an alternative for microbial detection in real-time. This study presents the limitation of conventional methods of detection in water and presents nanoparticles as a detection agent with possibility of incorporation into point-of-use detection. It is notable that nanosensors are currently emerging in the detection of bacteria, viruses and other pathogens in water and have been used in the detection of bacterial pathogens than viral. Nanosensors are established as good choice for rapid water analysis with application in point-of-use and analytical devices. In the use of nanozymes, the choice over natural enzymes can be linked to their unique and excellent catalytic activities, cost-effectiveness and ease of mass production.

Gut microbiota (GM) plays a pivotal role in human health and disease, and its alterations have been implicated in various neurological disorders, including Parkinson's disease (PD). Growing evidence reveals correlations between the abundance of specific bacterial taxa and the severity of motor symptoms and intestinal dysfunction in PD. Moreover, bacterial metabolites have been shown to influence α-synuclein (α-syn) aggregation and neurodegeneration. This narrative review aims to explore the current understanding of the gut-brain axis in PD, specifically the connection between GM and α-syn function in PD experimental models and patients. Several therapeutic strategies aimed at modulating gut microbiota, such as dietary interventions, fecal microbiota transplantation, and targeted bacterial therapies with the goal of alleviating or preventing PD symptoms, are examined. Understanding the mechanisms through which GM influence neurodegeneration, including inflammation, immune modulation, and microbial metabolite production, offers promising avenues for the development of novel therapeutic strategies targeting the microbiome.

The red color pigment prodigiosin is a potent antioxidant produced by different strains of Serratia marcescens and other bacteria. The bio pigment demonstrates many hopeful impending bioactivities. Prodigiosin is an active proapoptotic agent against various cancer cell lines. In the present study, pigment produced from soil isolate Serratia marcescens VITSD2 was characterized and identified using UV, FTIR, GC-MS and NMR analysis (¹H NMR and ¹³C NMR). The antiproliferative activity of prodigiosin pigment from Serratia marcescens VITSD2 was evaluated on cancer cell lines. The active sites and binding patterns of molecular marker survivin was analyzed on docking against prodigiosin.A strong antioxidant potential was noticed at 5 mg/mL concentration with 70 ± 0.08% scavenging activity (2,2-diphenyl-1-picrylhydrazyl)-DPPH. The dose dependent inhibition of HepG2 cell proliferation was observed maximum with 67 ± 0.08% cytotoxic activity at 50 µg/mL. When compared to other cell lines, A549, HL 60 and MCF-7, prodigiosin had a strong inhibitory activity on HepG2 cells. The Rf value of single band obtained in chromatography showed a value of 0.45. Maximum absorbance was observed at 535 nm. The pigment revealed the characteristic functional properties of the prodigiosin. On docking, the lowest binding energy exhibited was found to be -5.15 kcal/mol. The RMSD analysis indicated that the backbone structure converges at 18 ns before it attains stability. Pigment production from Serratia marcescens VIT SD2 offer a renewable and sustainable alternative to synthetic pigments, reducing dependence on nonrenewable resources. The study outcomes specified that the bio pigment prodigiosin extracted from Serratia marcescens VIT SD2 is a promising drug candidate for therapeutics.