Indian Journal of Microbiology最新文献

Chrysosporine, an exopolysaccharide, was produced by Chrysosporium articulatum KTL2, an endophyte of Ocimum sanctum L. It comprises arabinose, glucose, galactose, and fucose in a molar ratio of approximately 1:5:2:2 with a Mw ~ 2.95 × 10⁵ Da. One Variable at A Time, and Response Surface Quadratic Methodology analysed the maximum production of Chrysosporine at optimised laboratory conditions- 14 days of fermentation at 28 °C in fresh potato dextrose broth in a 250 mL conical flask with 50 mL medium provided with (g L^-1) glucose, 12; tryptone concentration, 1.75; NaCl, 0.05; with medium pH 6.5. Further addition of epigenetic modulator- Histone Methyltransferase Specific Probe BRD4770 promotes a 1.65-fold increase in Chrysosporine production. It is a potent radical scavenger and significantly uplifts some selected enzymatic antioxidant markers in peritoneal macrophage cells. Chrysosporine-fed rats have elevated counts of beneficial microflora of Lactobacillus sp. and less occurrence of putrefying Clostridium perfringens. Present outcomes suggest that Chrysosporine has a pharmaceutical interest as an exogenous antioxidant with prebiotic effectivities.

Supplementary information: The online version contains supplementary material available at 10.1007/s12088-024-01419-y.

The exploration of extreme environments to uncover microbial diversity has emerged as a promising strategy for the discovery of novel bioactive compounds. In this study, we isolated and characterized soil-dwelling actinomycetes from six samples collected from the Mingyong Glacier landscape. After 4 weeks of incubation, 73 terrestrial actinomycetes were isolated. They were selected based on the color of aerial mycelium, substrate mycelium, spore formation, and pigment production. Maximum actinobacterial population density was obtained from international Streptomyces project-2 agar (48.83%) followed by starch casein agar (24.65%), half strength ISP-2 (20.54%) and glycerin agar (11.26%). 16S rRNA gene sequence analyses identified phylogenetically diverse genera including Streptomyces, Nocardia, Micromonospora, Rhodococcus, Actinomycetia, Jiangella, Nonomuraea, Amycolatopsis and Pilimelia within the order Actinomycetales. Our findings reveal that soil from the Mingyong Glacier landscape contains a diverse range of actinomyces which may hold potential for isolating medicinal and pharmaceutical compounds. We also highlight the importance of isolating novel Actinomycetota lineages for drug discovery and the development of new therapies, stressing the role of genome mining and synthetic biology. Overall, this study provides valuable insights into the diversity and biotechnological prospects of actinomycetes from extreme environment paving the way for advancements in microbial-based drug discovery.

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Supplementary information: The online version contains supplementary material available at 10.1007/s12088-025-01449-0.

Escherichia phage CMSTMSU was isolated from a semi-intensive shrimp farm, and it demonstrated strong lytic activity against Escherichia coli. Further, the phage was purified, determined the titer value, and, expressed as plaque-forming units per milliliter (pfu/mL). A biofilm inhibition study was performed in high-density polyethylene against E. coli cells by applying phages at different concentrations. The results were viewed using confocal laser scanning microscopy. The results revealed that Escherichia phage CMSTMSU efficiently inhibited the E. coli's biofilm formation and evidenced that the weaker signals observed increasing concentration of pfu. To study the structural morphology, a transmission electron microscope was used and the results revealed that the phage head has a hexagonal shape measuring approximately 220-230 nm with a non-contractile tail belonging to the Siphoviridae family. The spectrophotometric experiment was conducted to examine the phage's killing effectiveness and the results revealed that after three hours, the phage destroyed the E. coli cells at a significant level (P <  = 0.001) in the liquid culture. The stability of Escherichia phage CMSTMSU was examined at various temperature and pH ranges. The stability studies showed that the phage was stable at temperatures of 40 and 50 °C and pH levels of 5 to 9 respectively and significantly (P <  = 0.001) varied. Finally, the growth curve was performed by measuring burst time and burst size, burst phases ranged from 20 to 140 min and the burst size progressively increased significantly (P < 0.05) as the time increased. The Escherichia phage CMSTMSU may be helpful for phage therapy against pathogenic E. coli because of its lytic capability.

Microbial fuel cells (MFC) have gained immense popularity in recent years as a promising sustainable technology to meet ever-growing energy demand. The MFC technology is based on the exploitation of catabolic activities of microorganisms for the conversion of organic waste to sustainable electricity. Many different substrates have been investigated for use as feedstock for MFC. Among the main substrates that have been used, the prominent one is lignocellulosic biomass (LCB). The LCB as a feedstock is a viable option due to its abundance and renewability. However, it cannot be directly utilized by the microorganisms for energy conversion due to its recalcitrant nature. There are several other practical limitations of MFCs in fulfilling high energy demands. The performance of the MFC depends not only on the substrates utilized but also on the microorganisms used, electrode material, the reactor design, and the operating parameters such as type of substrate, temperature, pH, oxygen flow rate electrode material and construction, and choice of catalyst. The article provides a complete understanding of Microbial fuel cells including the pretreatment methods to disintegrate the recalcitrance of LCB, the diversity and role of microorganisms used in biomass-fueled MFC, various aspects impacting their performance, power output, advantages, various challenges, and prospects.

Living organisms are exposed to various environmental stressors either directly or indirectly. Stressors can be natural or induced. Some of the stressors such as heavy metals are increasing in the environment due to the escalation of anthropogenic activities. Heavy metals enter the living cells and induce oxidative damage to macromolecules by the excessive generation of reactive oxygen species (ROS). Heavy metals are also known to interfere with the functioning of metalloproteins (proteins containing metal ions as cofactors) by modifying or replacing the essential divalent ions. Some of the essential metalloproteins play important role in cell defense and help to combat heavy metal stress. Thus, by studying the metal-protein interaction of metalloprotein, one can elucidate the role of metals in biological systems. This study focuses on characterization of enzymes belonging to complete glutathione cycle, i.e., superoxide dismutase (SOD1 and SOD2), catalase, glutathione peroxidase, phytochelatin synthase, and methionine sulfoxide reductase. In addition, identification, annotation, and characterization of metalloproteins (cadmium, copper, and cysteine-rich) involved in cell defense mechanisms from the whole genome data of freshwater ciliate, Tetmemena sp. SeJ-2015 (GenBank accession number LASU02000000) by systematic bioinformatic approach has also been carried out. In this study, Tetmemena sp. has been selected due to its high prevalence in freshwater bodies within the class Spirotrichea. This makes it a good model system to investigate its metal detoxification mechanism. The whole genome sequence data contained a total of 25,217 contigs out of which 17,044 contigs showed similarity with cadmium- (Cd-), copper- (Cu-) binding, and cysteine (cys) rich proteins. Further analysis of these 17,044 contigs indicated that around 7,597 were Cd-binding, 6,285 were Cu-binding, and 3,162 were Cys-rich proteins.

Supplementary information: The online version contains supplementary material available at 10.1007/s12088-024-01415-2.

The present study describes three lead-resistant bacterial isolates (KPb1, KPb5, and KPb7) that were isolated from water samples of the River Holy Kali Bein, Punjab, India. The isolates were found to resist and bioaccumulate lead, and maximum tolerated concentrations were found to be 750 mg/L by KPb1 and KPb5, and 800 mg/L by isolate KPb7, respectively. Additionally, isolates KPb1, KPb5, and KPb7 had Multiple Antibiotic Resistance (MAR) index values of 0.08, 0, and 0.25, respectively. The isolate KPb1 was identified as Klebsiella pneumonia, KPb5 as Serratia marcescens, and KPb7 as Microbacterium resistens based on biochemical analysis protein-based identification utilizing Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectroscopy and 16S rRNA sequencing. According to the findings, these strains were cultivated optimally at 37 °C and pH 7.0 for KPb5 and KPb7 and pH 7.5 for KPb1. Under optimum conditions, the bacterial isolates KPb7 showed the greatest potential for bioremediation, and reduced 100% of the lead in 96 h, KPb1 reduced 100% of the lead in 144 h, and KPb5 reduced 90% of the lead in 168 h. Our research established a baseline for the bioremediation of lead in an aqueous medium and concluded that these bacteria (KPb1, KPb5, and KPb7) are viable options for the bioremediation of lead.

Probiotic provide a different level of health benefits to human and animals. Many studies confirmed that probiotic supplement inhibits obesity, but these treatments are still restricted. As a probiotic Levilactobacillus brevis FS1 has been considered a potent bio-therapeutic agent to control several illnesses. In the present study, we examined theprobiotic potential of L. brevis FS1 and its cell free metabolites effect on the fat deposition and differentiation of 3T3-L1 adipocytes. The data suggested that L. brevis FS1 showed significant survival ability in harsh condition of gastrointestinal tract and had hydrophobicity and auto aggregation properties. Furthermore, cell free metabolites from L. brevis FS1 (CMLB) treatment reduced fat deposition and the genes related to adipogenesis and lipogenesis such as C/EBP-β (CCAAT/ enhancer-binding protein- β), PPAR-γ (Peroxisome proliferator activated receptor- γ), acetyl CoA carboxylase (ACC), Fatty acid synthase (FAS), adipocyte binding protein (aP2), Serum regulatory element binding protein-1 (SREBP-1) and increased insulin sensitizing protein adiponectin expression compared to control cells. The competitive study between CMLB and rosiglitazone (RGZ) confirmed that CMLB treatment reduced fat deposition and PPAR γ expression induced by PPAR γ agonist RGZ. It concludes that L. brevis FS1 may be considered as potent probiotic could be used for treatment of obesity and its associated diseases by downregulating key adipogenic and lipogenic markers.

Heavy metal pollution is result of large-scale industrialization and continuous anthropogenic activities which lead to cause severe environmental concern. Marine pollution is on rapid progress in recent years due to release of heavy toxicity induced by heavy metal pollutants and has become serious global threat for environmental security reasons. Bioremediation of marine heavy metal pollutants via marine microbial diversity is one of the most sustainable, adaptable and promising approach. Due to huge and versatile diversity, marine microbial diversity has capability to remediate the harmful heavy metals pollutants in the sea water and transform them into simple non-toxic products. Emphasis on the type of heavy metal pollutants remediation, marine microbial diversity and their mode of actions are the important points which need to be included in current research scenario and may be helpful towards more effective remediation of heavy metal pollutants in sea water. Therefore, the goal of this review paper has been set to explore the scope of marine microbial diversity, availability and their mode of action for the efficient bioremediation of heavy metal pollutants in the marine environment.

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On earth, soil is one of the most essential parts of nature which plays critical roles in plant growth, water flow, waste products recycling and provides habitats to various organisms. Soil is the combination of organic matter, air, water minerals, and sixteen different essential nutrient elements which are categorized into primary macronutrients, secondary macronutrients, and micronutrients. The nutrients elements present in soil either in organic forms or organic forms interchanged by the various microbial mechanisms such including fixation, chelation and solubilization. The microbes from all three domain i.e., archaea, bacteria, and eukarya have been reported for exhibiting the various mechanisms and strain belonging to genera Arthrobacter, Burkholderia, Bacillus, Paenibacillus, Pseudomonas, Rhizobium, Natrinema, and Serratia are widely known for ruling the nutrients dynamics. The microbes playing role in nutrients dynamics, have great economic importance in agriculture sector as agriculturist is in pressure of producing high quality and quantity of food along with managing the sustainability. These microbes could solve agricultural problems such as soil degradation and environmental pollution by using them as bio-fertilizer over chemical-based products. A huge number of reports have supported such statements so, the purpose of the present review aims to complies microbial role in all category nutrients dynamics and their role in plant growth promotion.

Growth anomalies of corals are characterized by spherical or irregular-shaped overgrowth of the coral skeleton that can drain the coral's energy and suppress coral growth. A localised outbreak of growth anomalies with a 40% prevalence rate in Turbinaria mesenterina colonies was observed during March 2018 in the study area. To further investigate, we characterised the gross morphology and used 16S rRNA amplicon sequencing to compare the bacterial communities associated with healthy and growth anomalies affected T. mesenterina colonies. Significant changes were observed in the bacterial communities where the Bacteroides group dominant in the healthy corals was replaced by opportunistic groups like Planctomycetes, Verrucomicrobia, Acidobacteria, and Cyanobacteria. Several human pathogens and copiotrophic coral pathogens were detected in the diseased colonies, indicative of an immune-compromised coral by harbouring opportunistic bacteria. The presence of human pathogens and fecal enterobacteria is an indicator of anthropogenically polluted reefs. Functional annotation revealed a major shift in bacterial community governing sulphur and nitrogen cycling that indicates metabolic changes in GA-affected corals. This study reports the first incidence of GA outbreak in the marginal reef of Grande Island and provides information on the pattern and role of the associated microbial community.

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Supplementary information: The online version contains supplementary material available at 10.1007/s12088-024-01410-7.