Journal of Basic Microbiology最新文献

Shiitake mushrooms (Lentinula edodes) hold significant cultural and economic value, particularly in Asia where they are extensively cultivated. The diversification of shiitake cultivars, driven by the need to adapt to various climatic conditions and cultivation methods, has resulted in over 200 distinct cultivars. Reliable identification of these cultivars is crucial for breeding, intellectual property protection, and effective genetic resource management. Traditional morphological methods are inadequate due to their subjectivity and labor-intensive nature. This study leverages nanopore high-throughput sequencing to comprehensively analyze the rDNA regions (SSU, ITS, LSU, IGS) of 41 shiitake strains from Taiwan's Bioresource Collection and Research Center (BCRC), comprising 5 wild strains, 33 commercial strains, and 3 wild-commercial hybrids. Our results identified the IGS1 region as the most variable and suitable for cultivar differentiation. Consequently, we developed an interactive online database (https://github.com/Raingel/ShiitakeIGS1) that integrates 317 IGS1 sequences from Taiwan, Japan, and China. This platform allows users to upload their IGS1 sequences and identify similar cultivars through a user-friendly interface, enhancing the precision and efficiency of shiitake cultivar identification.

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The functional network analysis shows interaction of proteins (circular) with metabolites (capsule-shaped) to show how the small molecules activated, inhibited, bound, or catalyzed the protein partners. Fungal isolates of marine origin Aspergillus sp. GSBT S13 and Aspergillus sp. S14 were compared to Aspergillus fumigatus volatilome and common metabolites were identified using an isolate of plant origin, Bulbithecium sp. GSBT E3 to identify common metabolites and pathways (see this issue, jobm.202400210).

(Figure: Mancheary John Prathyash Ushus, Department of Biotechnology, GITAM School of Science, Visakhapatnam, Andhra Pradesh, India)

Bacteria have a very well-regulated mechanism for chromosome segregation and cell division. This process requires a large number of complex proteins to participate and mediate their functionality. Among these complex proteins, ParA and ParB play a vital role for the faithful segregation of chromosome. In Rhodococcus erythropolis PR4, besides the essential parAB operon, there are three orphan copies of parA genes. Here, we report that the orphan ParA2 and ParA3 have distinct roles in the cell cycle. The disruption of the orphan parA2 or parA3 gene resulted in elongated cells. Multiple septal rings and mislocalised septa were observed in ΔparA3 and ΔparA2 mutants, respectively. The subcellular localization of ParA2 revealed a distinct ring- and ribbon-like structure. On the other hand, orphan ParA3 was localized slightly away from the poles. The orphan ParA proteins were found to interact with ParB, the strongest interaction was observed with ParA2. Further, asynchronous replication initiation was observed in ΔparA3 mutants suggesting its role in replication. This is the first report demonstrating the distinct roles of orphan parA genes from Rhodococcus.

Polycyclic aromatic hydrocarbons (PAHs), one of the major environmental pollutants, produced from incomplete combustion of materials like coal, oil, gas, wood, and charbroiled meat, that contaminate the air, soil, and water, necessitating urgent remediation. Understanding the metabolic pathways for PAHs degradation is crucial to preventing environmental damage and health issues. Biological methods are gaining increasing interest due to their cost-effectiveness and environmental friendliness. These methods are particularly suitable for remediating PAHs contamination and mitigating associated risks. The paper also outlines the processes for biodegrading PAHs, emphasizing the function of Pseudomonas spp., a kind of bacterium recognized for its capacity to degrade PAHs. To eliminate PAHs from the environment and reduce threats to human health and the environment, Pseudomonas spp. is essential. Understanding the mechanism of PAH breakdown by means of microbes could lead to effective clean-up strategies. The review highlights the enzymatic capabilities, adaptability, and genetic versatility of the genes like nah and phn of Pseudomonas spp., which are involved in PAHs degradation pathways. Scientific evidence supports using Pseudomonas spp. as biocatalysts for PAHs clean-up, offering cost-effective and eco-friendly solutions.

The study assessed Trichoderma spp. as a biocontrol agent for managing wilt-nematode complex in tomato crops, aiming to mitigate yield losses. Fusarium sp. and Meloidogyne sp. were isolated from infected plant samples and confirmed molecularly and morphologically as Fusarium oxysporum f.sp. lycopersici and Meloidogyne incognita. Four Trichoderma spp. procured from the Department of Plant Pathology, Tamil Nadu Agricultural University, India were identified molecularly as Trichoderma asperellum (Tv1), Trichoderma asperelloides (Tasd1), Trichoderma harzianum (Th1), and Trichoderma koningiopsis (Tk1) utilizing ITS and TEF1 primer pairs. Among them, Tv1 effectively inhibited the mycelial growth of pathogen isolates. Furthermore, crude metabolite of Tv1 exhibited similar effects. The mortality rate of M. incognita J2s ranged from 90.48% to 100% after 24-72 h of incubation and inhibition percentage of egg hatching reached 90.20%. The shoot length, root length, fresh weight, and dry weight of the tomato plants treated with Tv1 conidia were increased. In a pot experiment, Tv1 treatment reduced disease incidence by 64.57%, comparable to carbendazim treatment (82.32%). Tv1-treated plants had fewer root galls, egg masses, and J2s per 100 g of roots than the inoculated-untreated control plants. The root-knot index (RKI) was significantly lower in plants treated with carbafuran (1.98 ± 0.047) and Tv1 (3.06 ± 0.086) than in control (4.47 ± 0.109). The bio-control efficiency of Tv1 against M. incognita was 21.04%, and the nematodes' reproductive factor (RF) declined to 0.53 in Tv1 treatment group. Based on the findings above, it was established that Tv1 effectively controlled nematode populations and wilt disease when applied in soil.

Oil seeds sector is one of the major dynamic components of the agriculture world. Oil seeds such as canola (Brassica napus) require a higher quantity of sulfur (S), which is supplied through inorganic fertilizers. However, the overapplication of agro-chemicals to get higher yields of crops is harming the soil health. Therefore, the application of bacterial cultures with plant growth-promoting activity as biofertilizers ensures soil health maintenance and enhances crop productivity. To achieve this aim, the present research was initiated by procuring three sulfur-oxidizing bacteria (SOBs), namely, SOB 5, SOB 10, and SOB 38, from the Microbiology Department, PAU. In the initial assessment, all three SOB cultures showed resilience to pesticide toxicity at the recommended dosage, with the exception of ridomil. These cultures were later characterized morphologically, biochemically, and at the molecular level using 16s rRNA resulting in their identification as Enterobacter ludwigii strain Remi_9 (SOB 5), Enterobacter hormaechei strain AUH-ENM30 (SOB 10), and Bacillus sp. 5BM21Y12 (SOB 38). Functional characterization of these SOB cultures revealed their ability to exhibit multifarious plant growth-promoting traits. Bacillus sp. 5BM21Y12 showed greater functional activity, including high P solubilization (14.903 µg/mL), IAA production (44.28 µg/mL), siderophore production (13.89 µg/mL), sulfate ion production (0.127 mM), ammonia excretion (2.369 µg/mL), and Zn solubilization (22.62 mm). Based on the results of functional and molecular characterization, Bacillus sp. 5BM21Y12 was selected for field trials by formulating different treatments. Composite treatment, T8 (100% S + Bacillus sp. + pesticides) significantly enhanced growth parameters (plant height, root, and shoot biomass), yield attributes (siliqua length, test weight, number of siliqua/plant), yield parameter (total biomass and seed yield), quality parameter (crude protein and oil) as compared to all other sole treatments employed in the field. A combined application of non-pathogenic Bacillus sp. 5BM21Y12, with good functional activity enhanced yield of crop due to synergistic and additive interaction with fertilizer/pesticides. As biofertilizer application reduces the input of pesticides/fertilizers new inoculant formulations with cell protectors and the development of compatible pesticides should be searched to assure the benefits of integrated treatment.

In this study, biogenically synthesized AuNPs were first characterized via UV visible spectroscopy, SEM, XRD, and FTIR followed by toxicity evaluation using mice model. UV-visible spectroscopy of biogenic AuNPs showed peaks at 540-549 nm, while FTIR spectrum showed various functional groups involving O-H, Amide I, Amide II, O-H, C-H groups, and so on. SEM showed the size variation from 30 to 60 nm. Antibacterial potential against pathogenic isolates showed bigger ZOI (31.0 mm) against Pseudomonas aeruginosa AuNPs. Antibiofilm activity showing up to 100% inhibition at 90 µg mL^-1 concentration of AuNPs. Toxicity evaluation showed LD₅₀ as 70 mg kg^-1. Exposure to AuNPs caused significant changes in the levels of serum AST (p < 0.05) at 100-150 mg kg^-1 of AuNPs exposure. Histopathology of male albino mice kidney and liver revealed that mice exposed to maximum concentration of AuNPs showed necrosis, cell distortion, and hepatocytes detachment. Present study showed that biologically synthesized AuNPs possess effective antimicrobial and biofilm inhibitory potential. AuNPs strong bactericidal effect even at lower concentration suggest that NPs could have excellent potential for combating pathogens. In conclusion, nanotechnology may revolutionize human life and medical industry by developing innovative drugs with the potential to treat diseases in shorter and noninvasive time period. Hence, in vitro biosafety and experimental observations followed by in vivo outcomes are crucial in shifting the novel therapeutics into medical practice thus leading further into their future development.

Heavy metal pollution has become a significant concern as the world continues to industrialize, urbanize, and modernize. Heavy metal pollutants impede the growth and metabolism of plants. The bioaccumulation of heavy metals in plants may create chlorophyll antagonism, oxidative stress, underdeveloped plant growth, and reduced photosynthetic system. Finding practical solutions to protect the environment and plants from the toxic effects of heavy metals is essential for long-term sustainable development. The direct use of suitable living plants for eliminating and degrading metal pollutants from ecosystems is known as phytoremediation. Phytoremediation is a novel and promising way to remove toxic heavy metals. Plant growth-promoting rhizobacteria (PGPR) can colonize plant roots and help promote their growth. Numerous variables, such as plant biomass yield, resistance to metal toxicity, and heavy metal solubility in the soil, affect the rate of phytoremediation. Phytoremediation using the PGPR consortium can speed up the process and increase the rate of heavy metal detoxification. The PGPR consortium has significantly increased the biological accumulation of various nutrients and heavy metals. This review sheds light on the mechanisms that allow plants to uptake and sequester toxic heavy metals to improve soil detoxification. The present review aids the understanding of eco-physiological mechanisms that drive plant-microbe interactions in the heavy metal-stressed environment.

Petroleum and other oil manufacturing industries contribute to environmental pollution by releasing hazardous hydrocarbons. Biosurfactants offer a sustainable solution for mitigating oil pollution through emulsification processes, safeguarding agricultural soils, aquatic ecosystems, and human health. This study focuses on isolating, screening, and identifying actinomycetes producing biosurfactant from oil-polluted soil in the naval dockyard of Visakhapatnam. Biosurfactant production was successfully achieved utilizing Kim's medium, which was supplemented with olive oil serving as the carbon source. The evaluation involved preliminary identification tests, including oil displacement, Parafilm-M, and lipase activity assays, using sodium lauryl sulfate as the standard reference. Surface tension and emulsification index measurements were conducted, and the chemical composition of glycolipids and phospholipids was elucidated using phenol-sulfuric acid and phosphate assays. Glycolipids, specifically identified as rhamnolipids, were confirmed via cetyltrimethylammonium bromide (CTAB) testing and quantitatively analyzed using the orcinol method. The cell-free broth exhibited antagonistic activity against Gram-positive and negative bacilli.16S rRNA sequencing-based phylogenetic analysis was carried out by the NCIM, Pune, with the gene sequence being deposited in GenBank. Further characterization of isolate B2 included scanning electron microscopy (SEM) analysis, as well as physiological and biochemical assays. This study highlights the ability of Nocardiopsis dassonvillei var. B2, isolated from oil-polluted soil, to produce biosurfactants, specifically glycolipids identified as rhamnolipids. Our findings represent the first reported instance of biosurfactant production from isolate B2 originating from the naval dockyard in Visakhapatnam, Andhra Pradesh, India.