16S rRNA Gene Sequence Analysis Research Articles

Characterization of Sinorhizobium strains isolated from arid and semi-arid areas of Morocco promoting the growth of Vachellia gummifera

Vachellia gummifera is a nitrogen-fixing shrub endemic to Morocco, and represents a suitable candidate for reforestation programs in dry areas. In this study, we identified seven root microsymbionts of V. gummifera, and determined their phenotypic characteristics, Plant Growth-Promoting (PGP) activities and their symbiotic efficiency. The bacteria were isolated from root nodules of the plant grown in Moroccan forest soils located in arid and semi-arid regions. The 16S rRNA gene sequences analysis of seven isolates showed similarity values ranging from 99.85% to 99.92% with Sinorhizobium fredii USDA205T. The phenotypic analyses displayed that the strains use different carbohydrates, mainly mono and di-saccharides, as a sole carbon source, and 13 out of 15 amino acids tested as the sole nitrogen source. The strains have variable tolerance to heavy metals, but are sensitive to salinity and high temperature, as no one grew in the presence of 2% NaCl (w/v) or at 40 °C, respectively. On the other hand, the strains grew in a very high osmotic stress environment induced by PEG 6000 (20% w/v), and they all grow in a pH range between 6.5 and 9. The strains possess PGP activities, such as phosphate solubilization, siderophore, and indole acetic acid production. Inoculation under axenic conditions showed that the strains increased the aerial biomass of inoculated plants up to 217%, whereas the relative symbiotic efficiency percentages (74.87–140,3%) showed that most strains are very efficient. From all these results we concluded that our strains may be proposed as inoculum for large-scale applications, such as reforestation programs.

Ginsenoside compound K alleviates D-galactose-induced mild cognitive impairment by modulating gut microbiota-mediated short-chain fatty acid metabolism.

The occurrence and progression of mild cognitive impairment (MCI) are closely related to dysbiosis of the gut microbiota. Ginsenoside compound K (CK), a bioactive component of ginseng, has been shown to alleviate gut microbiota dysbiosis and neural damage. However, the mechanisms by which CK regulates the gut microbiota to improve MCI remain unexplored. In this study, an MCI mouse model induced by D-galactose was used, and 16S rRNA gene sequencing, metabolomics, transcriptomics, and integrative multi-omics analyses were employed to investigate the potential mechanisms by which CK alleviates MCI through modulation of the gut microbiota. The results demonstrated that CK repaired intestinal barrier dysfunction caused by MCI, improved blood-brain barrier (BBB) integrity, inhibited activation of microglial cells and astrocytes, and significantly ameliorated MCI. Furthermore, CK enhanced gut microbiota diversity, notably enriched beneficial bacteria such as Akkermansia, and modulated the levels of short-chain fatty acids (SCFAs), particularly increasing propionate, thereby alleviating gut microbiota dysbiosis caused by MCI. Germ-free experiments confirmed that gut microbiota is a key factor for ginsenoside CK in relieving MCI. Further investigation revealed that CK regulated the TLR4-MyD88-NF-κB signaling pathway through modulation of gut microbiota-mediated propionate metabolism, significantly reducing systemic inflammation and alleviating MCI. Our findings provide a new theoretical basis for using CK as a potential means of modulating the gut microbiota for the treatment of MCI.

Buqi-Huoxue-Tongnao decoction drives gut microbiota-derived indole lactic acid to attenuate ischemic stroke via the gut-brain axis

BackgroundIschemic stroke belongs to “apoplexy” and its pathogenesis is characterized by qi deficiency and blood stasis combining with phlegm-damp clouding orifices. Buqi-Huoxue-Tongnao decoction (BHTD) is a traditional Chinese medicine formula for qi deficiency, blood stasis and phlegm obstruction syndrome. However, its efficacy and potential mechanism on ischemic stroke are still unclear. This study aims to investigate the protective effect and potential mechanism of BHTD against ischemic stroke.Materials and methodsMiddle cerebral artery occlusion (MCAO) surgery was carried out to establish an ischemic stroke model in rats. Subsequently, the rats were gavaged with different doses of BHTD (2.59, 5.175, 10.35 g/kg) for 14 days. The protective effects of BHTD on the brain and gut were evaluated by neurological function scores, cerebral infarction area, levels of brain injury markers (S-100B, NGB), indicators of gut permeability (FD-4) and bacterial translocation (DAO, LPS, D-lactate), and tight junction proteins (Occludin, Claudin-1, ZO-1) in brain and colon. 16S rRNA gene sequencing and metabolomic analysis were utilized to analyze the effects on gut microecology and screen for marker metabolites to explore potential mechanisms of BHTD protection against ischemic stroke.ResultsBHTD could effectively mitigate brain impairment, including reducing neurological damage, decreasing cerebral infarction and repairing the blood–brain barrier, and BHTD showed the best effect at the dose of 10.35 g/kg. Moreover, BHTD reversed gut injury induced by ischemic stroke, as evidenced by decreased intestinal permeability, reduced intestinal bacterial translocation, and enhanced intestinal barrier integrity. In addition, BHTD rescued gut microbiota dysbiosis by increasing the abundance of beneficial bacteria, including Turicibacter and Faecalibaculum. Transplantation of the gut microbiota remodeled by BHTD into ischemic stroke rats recapitulated the protective effects of BHTD. Especially, BHTD upregulated tryptophan metabolism, which promoted gut microbiota to produce more indole lactic acid (ILA). Notably, supplementation with ILA by gavage could alleviate stroke injury, which suggested that driving the production of ILA in the gut might be a novel treatment for ischemic stroke.ConclusionBHTD could increase gut microbiota-derived indole lactic acid to attenuate ischemic stroke via the gut-brain axis. Our current finding provides evidence that traditional Chinese medicine can ameliorate central diseases through regulating the gut microbiology.

Unveiling the antimicrobial and antibiofilm potential of biosurfactant produced by newly isolated Lactiplantibacillus plantarum strain 1625

The present study aimed to characterize the biosurfactants synthesized by lactic acid bacteria (LAB) obtained from fermented foods, optimize the conditions for increasing the yield of biosurfactants and explore their antimicrobial and antibiofilm potential. Out of the 26 LAB isolates, isolate BS2 showed the highest biosurfactant production as indicated in the oil displacement test, drop collapse and emulsification activity. BS2 was identified as Lactiplantibacillus plantarum 1625 using 16S-rRNA gene sequencing and phylogenetic analysis. The biosurfactant produced by BS2 was identified as an anionic glycol-lipo-proteins by employing Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography–Mass Spectrometry (GC–MS) analysis. The biosurfactants produced by L. plantarum 1625 demonstrated strong antibacterial and antibiofilm characteristics against pathogenic strains such as Staphylococcus aureus MTCC 1049, Escherichia coli MTCC 1587, and Pseudomonas putida MTCC 1655. The minimal inhibition concentration value of antibacterial activity was found to be 0.1 mg/mL with the inhibition percentage ranging from 90 to 95%. Further, the effect of temperature, pH, and substrate composition on biosurfactant production was also studied to enhance it production using the Box–Behnken Design approach of Response surface methodology (RSM). Application of biosurfactant led to a considerable decrease in biofilm-forming harmful bacteria, as proven by scanning electron microscopy analysis. The results highlight the potential uses of biosurfactants in distinct industries, and biotechnological contexts, especially in the creation of new antimicrobial and antibiofilm agents.

Dysbiosis-activated IL-17-producing T cells promote skin immunopathological progression in mice deficient of the Notch ligand Jag1 in keratinocytes

BackgroundThe Notch signaling pathway is an evolutionarily conserved regulatory cascade critical in skin development and homeostasis. Mice deficient of Notch signaling molecules have impaired skin and hair follicle development associated with local tissue inflammation. However, mechanisms underlying skin inflammation and pathology resulting from defective Notch signals are not well understood. ObjectiveTo dissect molecular and cellular mechanisms underlying development of skin immunopathology in mice defective of the Notch ligand Jagged-1 (Jag1). MethodsWe assessed involvement of microbiota and immune cell subsets in skin pathogenic symptoms in Foxn1CreJag1fl/fl mice that were deficient of Jag1 in keratinocytes. We also used RNA-seq and 16S rRNA gene-seq analyses to identify molecular factors and bacterial species contributing to skin pathologic symptoms in Foxn1CreJag1fl/fl mice. ResultsCompared to Jag1-sufficient littermate control mice, Foxn1CreJag1fl/fl mice had specific expansion of IL-17a-producing T cells accompanying follicular and epidermal hyperkeratosis and cyst formation while antibody blockage of IL-17a reduced the skin pathology. RNA-sequencing and 16S rRNA gene-sequencing analyses revealed dysregulated immune responses and altered microbiota compositions in the skin of Foxn1CreJag1fl/fl mice. Antibiotic treatment completely prevented over-activation of IL-17a-producing T cells and alleviated skin pathology in Foxn1CreJag1fl/fl mice. ConclusionDysbiosis-induced over-activation of IL-17a-producing T cells is critically involved in development of skin pathology in Foxn1CreJag1fl/fl mice, establishing Foxn1CreJag1fl/fl mice as a useful model to study pathogenesis and therapeutic targets in microbiota-IL-17-mediated skin inflammatory diseases such as hidradenitis suppurativa (HS) and psoriasis.

Microbiome resilience of three-toed box turtles (Terrapene carolina triunguis) in response to rising temperatures.

The gastrointestinal (GI) microbiome of chelonians (testudines) plays an important role in their metabolism, nutrition, and overall health but the GI microbiome of three-toed box turtles (Terrapene carolina triunguis) has yet to be characterized. How the GI microbiome responds to rapidly rising environmental temperatures has also not been studied extensively in ectotherms, specifically chelonians. In this study, twenty (20) T.c.triunguis were split into control and experimental groups. The experimental group experienced 4.5°C increases every two weeks while the control group stayed at a constant ambient temperature (24°C) through the entirety of the experiment. Before each temperature increase, all turtles had cloacal swab samples taken. These samples underwent DNA extraction followed by 16S rRNA gene sequencing and microbial community analyses. Differences in diversity at the community level in the controls compared to the experimental groups were not statistically significant, indicating microbiome resilience to rapid temperature changes in T.c.triunguis, although some differentially abundant lineages were identified. Interestingly, an amplicon sequence variant belonging to the Erysipelothrix spp. was exclusively enriched in the highest temperature group relative to controls. Overall, our work suggests that there may be an innate robustness to rapid temperature swings in the microbiome of T.c.triunguis which are native to temperate North America. Despite this resilience, Erysipelothrix spp. was enriched at the highest temperature. Phylogenetic analysis of this amplicon variant showed that it is a close relative of Erysipelothrix rhusiopathiae, a pathogen of zoonotic importance associated with both wildlife and livestock.

Microbiome and Metabolomic Profiling in humans with Functional Anorectal Pain: Identifying Key Players in Disease Pathogenesis

Functional Anorectal Pain (FARP) is a chronic, functional, nonorganic disorder of the anorectal region, often misdiagnosed as various types of anorectal organic diseases in clinical practice. However, the pathogenesis and diagnostic markers of FARP remain poorly understood. In this study, we recruited 45 FARP patients and 35 healthy subjects to investigate the microbial and metabolomic profiles associated with FARP progression. Anorectal manometry was utilized to determine changes in anal pressure, revealing a significant decrease in FARP patients' anal resting pressure and maximum anal squeeze pressure. Through 16S rRNA gene sequencing and metabolomics analysis, we identified specific microbial genera, including Propionibacterium, Ruminococcus2, and Bilophila, and specific metabolite profiles, including Gentisic acid, 2-Naphthalenethiol, 2-Furancarboxaldehyde, Benzoic acid, Allose, and (S)-3-Amino-5-methylhexanoic acid, that were closely correlated with FARP. In-depth analysis revealed that the Phospholipase D (PLD) signaling pathway exhibited significant differences in FARP. Additionally, serum cortisol levels were found to be significantly elevated in FARP patients. These findings provide new insights into the anorectal manometry features, gut microbiota, and serum metabolome associated with FARP, potentially contributing to improved clinical diagnosis and therapeutic strategies for FARP.

Impact of mechanical bowel preparation on the gut microbiome of patients undergoing left-sided colorectal cancer surgery: randomized clinical trial.

Postoperative complications after colorectal cancer surgery have been linked to the gut microbiome. However, the impact of mechanical bowel preparation using oral preparation agents or rectal enema on postoperative infections remains poorly understood. This study aimed to compare the impact of oral preparation and rectal enema on the gut microbiome and postoperative complications. This open-label pilot RCT was conducted at the National Cancer Institute, Vilnius, Lithuania. Patients with left-side colorectal cancer scheduled for elective resection with primary anastomosis were randomized 1 : 1 to preoperative mechanical bowel preparation with either oral preparation or rectal enema. Stool samples were collected before surgery, and on postoperative day 6 and 30 for 16S rRNA gene sequencing analysis. The primary outcome was difference in β-diversity between groups on postoperative day 6. Forty participants were randomized to oral preparation (20) or rectal enema (20). The two groups had similar changes in microbiome composition, and there was no difference in β-diversity on postoperative day 6. Postoperative infections occurred in 12 patients (32%), without differences between the study groups. Patients with infections had an increased abundance of bacteria from the Actinomycetaceae family, Actinomyces genus, Sutterella uncultured species, and Enterococcus faecalis species. Mechanical bowel preparation with oral preparation or rectal enema resulted in similar dysbiosis. Patients who experienced postoperative infections exhibited distinct gut microbiome compositions on postoperative day 6, characterized by an increased abundance of bacteria from the Actinomycetaceae family, Actinomyces genus, Sutterella uncultured species, and Enterococcus faecalis species. NCT04013841 (http://www.clinicaltrials.gov).

'Candidatus Phytoplasma vignae', assigning a species description to a long-known phytoplasma occurring in northern Australia.

Gene- and genome-based approaches were used to determine whether Vigna little leaf (ViLL) phytoplasma, which occurs in northern Australia, is a distinct 'Candidatus Phytoplasma' species. The ViLL 16S rRNA gene sequences exhibited the highest known similarity to species in the 16SrXXIX-A and 16SrIX-D subgroups, namely 'Candidatus Phytoplasma omanense' (98.03-98.10%) and 'Candidatus Phytoplasma phoenicium' (96.87-97.20%), respectively. A total of 48 single-copy orthologue genes were identified to be shared among the two draft ViLL phytoplasma genomes, 30 publicly available phytoplasma genomes, and one Acholeplasma laidlawii genome as the outgroup taxon. Phylogenomic assessments using the 48 shared single-copy orthologue genes supported that ViLL and 'Ca. Phytoplasma phoenicium' were closely related yet distinct species. The 16S rRNA gene sequence analysis and phylogenomic assessment indicate that ViLL phytoplasmas are a distinct taxon. As such, a novel species, 'Candidatus Phytoplasma vignae', is proposed. Strain BAWM-336 (genome accession number JAUZLI000000000) detected in Momordica charantia (bitter melon) serves as the reference strain of this species, with infected plant material deposited in the Victorian Plant Pathology Herbarium (VPRI) as VPRI 44369.

Microbial Diversity and Screening for Potential Pathogens and Beneficial Bacteria of Five Jellyfish Species-Associated Microorganisms Based on 16S rRNA Sequencing.

Jellyfish, microorganisms, and the marine environment collectively shape a complex ecosystem. This study aimed to analyze the microbial communities associated with five jellyfish species, exploring their composition, diversity, and relationships. Microbial diversity among the species was assessed using 16S rRNA gene sequencing and QIIME analysis. Significant differences in bacterial composition were found, with distinct dominant taxa in each species: Mycoplasmataceae (99.21%) in Aurelia coerulea, Sphingomonadaceae (22.81%) in Cassiopea andromeda, Alphaproteobacteria_unclassified (family level) (64.09%) in Chrysaora quinquecirrha, Parcubacteria_unclassified (family level) (93.11%) in Phacellophora camtschatica, and Chlamydiaceae (35.05%) and Alphaproteobacteria_unclassified (family level) (38.73%) in Rhopilema esculentum. C. andromeda showed the highest diversity, while A. coerulea exhibited the lowest. Correlations among dominant genera varied, including a positive correlation between Parcubacteria_unclassified (genus level) and Chlamydiaceae_unclassified (genus level). Genes were enriched in metabolic pathways and ABC transporters. The most abundant potential pathogens at the phylum level were Proteobacteria, Tenericutes, Chlamydiae, and Epsilonbacteraeota. The differing microbial compositions are likely influenced by species and their habitats. Interactions between jellyfish and microorganisms, as well as among microorganisms, showed interdependency or antagonism. Most microbial gene functions focused on metabolic pathways, warranting further study on the relationship between pathogenic bacteria and these pathways.

A novel clinically relevant human fecal microbial transplantation model in humanized mice.

The intact immune system of mice exhibits resistance to colonization by exogenous microorganisms, but the gut microbiota profiles of the humanized mice and the patterns of human fecal microbiota colonization remain unexplored. Humanized NCG (huNCG) mice were constructed by injected CD34 +stem cells. 16S rRNA sequencing and fecal microbiota transplantation (FMT) technologies were used to detect the differences in microbiota and selective colonization ability for exogenous community colonization among three mice cohorts (C57BL/6J, NCG, and huNCG). Flow cytometry analysis showed that all huNCG mice had over 25% hCD45 +in peripheral blood. 16S rRNA gene sequence analysis showed that compared with NCG mice, the gut microbiota of huNCG mice were significantly altered. After FMT, the principal coordinates analysis (PCoA) showed that the gut microbial composition of huNCG mice (huNCG-D9) was similar to that of donors. The relative abundance of Firmicutes and Bacteroidetes were significantly increased in huNCG mice compared to NCG mice. Further comparison of ASV sequences revealed that Bacteroides plebeius, Bacteroides finegoldii, Escherichia fergusonii, Escherichia albertii, Klebsiella pneumoniae, and Klebsiella variicola exhibited higher abundance and stability in huNCG mice after FMT. Furthermore, PICRUSt2 analysis showed that huNCG mice had significantly enhanced metabolism and immunity. This study demonstrated that humanized mice are more conducive to colonization within the human gut microbiota, which provides a good method for studying the association between human diseases and microbiota.IMPORTANCEThe gut microbiota and biomarkers of humanized mice are systematically revealed for the first time. The finding that human fecal microbiota colonize humanized mice more stably provides new insights into the study of interactions between immune responses and gut microbiota.

Phenotypic and genotypic characterization of methicillin resistant Staphylococcus aureus associated with pyogenic infections.

Staphylococcal infections are one of the major infectious diseases affecting globally in spite of advances in development of antimicrobial agents. Knowledge and awareness about the local pattern and prevalence of MRSA infections plays a key role in treatment. The aim of this study was to identify MRSA strains by phenotypic and genotypic methods and to analyze the antibiotic susceptibility pattern of MRSA strains from patients attending a tertiary care hospital. This study was conducted over a period of 1 year, where 296 isolates of Staphylococcus aureus were isolated from various clinical specimens. The isolated strains were examined for antibiotic susceptibility by the modified Kirby Bauer disc diffusion method. Methicillin resistance was detected by cefoxitin disk diffusion test. A total of 104 isolates were found to be MRSA and 192 were found to be MSSA. Among the 104 MRSA isolates, 10 strains that were multidrug resistant were subjected to 16S rRNA gene sequencing analysis. All the 10 strains had a 99% match with S. aureus strains that were responsible for causing some serious biofilm mediated clinical manifestations like cystic fibrosis and device mediated infections. The biofilms were quantified using crystal violet staining and their ability to produce biofilms was analyzed using scanning electron microscopy and matched with the Genbank. Hence these phylogenetic analysis aid in treating the patients and combating resistance to antibiotics.

Rufibacter psychrotolerans sp. nov., a Cold-Tolerating Novel Species Isolated from Desert Soil.

Strain SYSU D00308T, a short-rod-shaped bacterium, was isolated from a sandy soil collected from the Gurbantunggut Desert, Xinjiang, PR China. Strain SYSU D00308T was Gram-stain-negative, aerobic, pink-pigmented, non-motile, catalase- and oxidase-positive. The strain grew at 4-37 ℃, pH 5.0-8.0 and 0-1.5% (w/v) NaCl. 16S rRNA gene sequencing analyses demonstrated that strain SYSU D00308T belonged to the genus Rufibacter and exhibited the highest sequence similarity (97.4%) to Rufibacter glacialis MDT1-10-3T. Summed features 3, 4, and iso-C15:0 were the major fatty acids, and menaquinone 7 (MK-7) was the sole respiratory menaquinone. The polar lipid profiles comprised phosphatidylethanolamine, an unidentified glycolipid, an unidentified phospholipid, two unidentified aminophospholipids, and two unidentified lipids. The genome size and DNA G + C content of strain SYSU D00308T were 5,176,683 bp and 54.8%, respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between SYSU D00308T and members of the genus Rufibacter were 77.7-81.8% and 20.4-23.4% respectively, which were less than the corresponding thresholds (ANI: 95-96%; dDDH: 70%) for prokaryotic species definition. According to the genotypic, phenotypic and phylogenetic characteristics, strain SYSU D00308T represents a novel species of the genus Rufibacter. We propose the name, Rufibacter psychrotolerans sp. nov., with SYSU D00308T (= CGMCC 1.18621T = KCTC 82275T = MCCC 1K04970T) as the type strain.

Bacillus spp. Isolated from Miang as Potential Probiotics in Nile Tilapia Culture-In Vitro Research.

Among 79 Bacillus spp. isolated from Miang, a fermented tea in north Thailand, 17 Bacillus strains were selected with probiotic potential in Nile tilapia culture based on the capabilities of bacteriocin production and associated antimicrobial activities against fish pathogens, Aeromonas hydrophila and Streptococcus agalactiae. However, only six isolates were selected for further extensive studies based on the strength of their antimicrobial activities and their tolerance against simulated gastrointestinal conditions. The molecular identification by 16S rRNA gene sequence analysis revealed that five isolates, K2.1, K6.1, K7.1, K15.4, and K22.6, were Bacillus tequilensis, and the isolate K29.2 was Bacillus siamensis. B. siamensis K29.2 showed complete susceptibility to antibiotics tested in this study, while B. tequilensis K 15.4 showed moderate resistance to some antibiotics; therefore, both strains were selected as potential probiotic bacteria. B. tequilensis K15.4 and B. siamensis K29.2 were capable of the production and secretion of extracellular protease and polysaccharide degrading enzymes, including cellulase, xylanase, and β-mannanase. The tannin tolerant test also demonstrated their ability to grow on selective agar plates and secrete cellulase and β-mannanase in the presence of hydrolyzable tannin. In addition, in vitro digestion of commercial fish substrate revealed that the extracellular enzymes produced by both strains efficiently reacted with feed protein and polysaccharides. Based on the results from this study, B. siamensis K29.2 was deemed to have the highest potential multifunctional probiotic qualities for application in Nile tilapia culture, while the antibiotic-resistant gene in B. tequilensis K15.4 must be clarified before field application.

Molecular characterization and validation of zinc solubilization potential of bacteria isolated from onion (Allium cepa L.) rhizosphere

Zinc (Zn) is essential for optimal plant growth and nutrition, while zinc-solubilizing bacteria (ZSB) enhance plant accessibility to zinc by converting its insoluble forms into usable ones. The primary objective of this research was to isolate and identify Zn-solubilizing strains from the onion rhizosphere and evaluate their ability to solubilize different insoluble Zn compounds, including ZnO, ZnCO3, and Zn3(PO4)2. Of the nineteen bacterial isolates retrieved, fifteen demonstrated the ability to solubilize inorganic Zn compounds based on plate assay techniques. The Zn-solubilizing bacterial strains, selected for their qualitative properties, underwent quantitative testing in broth culture using atomic absorption spectrophotometry (AAS) and Field Emission-Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (FE-SEM-EDS). Seven bacterial isolates with a high capacity to solubilize Zn were identified based on 16S rRNA gene amplification and sequence analysis. These isolates were affiliated with Pantoea eucrina, Pantoea dispersa, Pseudomonas aeruginosa, Bacillus velezensis, and Pseudomonas fluorescens. Notably, this study is the first to report the potential of Pantoea eucrina as a ZSB. The strain Pantoea eucrina ZSC9 exhibited the maximum Zn solubilization index (8.85) and the highest soluble Zn content (624 mg L−1) among the three insoluble Zn compounds, with ZnO being the most effectively solubilized on the 10th day of incubation in ZnO-enriched basal medium. All bacterial isolates were more effective at solubilizing ZnO than ZnCO3 and Zn3(PO4)2, and this solubilization led to a significant drop in the pH of the broth. Pantoea eucrina ZSC9 showed the maximum pH reduction (3.82) in a ZnO-supplemented medium, indicating a negative correlation between broth pH and Zn solubilization. Seven selected ZSB strains were assessed for their potential to enhance onion growth under pot house conditions. The results showed that inoculating onion seedlings with these ZSB strains significantly improved their growth. Among the strains tested, ZSC9, ZSC10, and ZSC17 were the most effective, enhancing growth attributes such as plant height, bulb diameter, fresh and dry weight of bulbs, Zn uptake by the plant, and overall bulb yield compared to other strains. These findings suggest that these ZSB isolates have great potential as biofertilizers to enhance plant growth and development.

Oral microbiota diversity in moderate to severe plaque psoriasis, nail psoriasis and psoriatic arthritis

Gaining a comprehensive understanding of the role played by the oral microbiome in moderate to severe plaque psoriasis and its potential implications for disease management and development holds significant importance. With the objective of exploring correlations between the oral microbiota and severe psoriasis, this study involved 72 severe psoriasis patients and 16 healthy individuals, whose clinical manifestations and living habits were carefully recorded. Cutting-edge techniques such as 16S rRNA gene sequencing and bioinformatics analysis were employed to compare the microbial flora, investigating dynamic changes among severe plaque psoriasis patients, psoriatic arthritis patients and healthy individuals. The findings revealed noteworthy patterns including increased levels of Aggregatibacter in the psoriatic arthritis group, accompanied by a decrease in the level of Prevotella. Moreover, the enrichment o Capnocytandophaga (P = 0.009), Campylobacter (P = 0.0022), and Acetobacter (P = 0.0292) was notably more substantial in the psoriasis group compared to the control group, whereas certain bacterial species such as Bacteroides (P = 0.0049), Muribaculaceae (P = 0.0048) demonstrated decreased enrichment. Additionally, the psoriatic arthritis group exhibited significantly higher levels of Ralstonia, Bifidobacterium and Micromonospora. Based on these findings, it can be inferred that individuals with lower levels of Prevotella and higher levels of Corynebacterium may be more susceptible to psoriasis exacerbation.

Prevalence and molecular characterization of ticks infesting dogs in Agartala, Tripura

Due to its ability to spread disease from one host to another, tick infestation is the most frequent issue pet owners’ deal with and should be taken seriously. The goal of the current study was to ascertain the prevalence of tick infestation in dogs in Agartala as well as its molecular identity and characterisation. A total of 1776 dogs of various breeds, ages, sexes, and categories were included in the study, which was conducted from March 2022 to February 2023 over the course of a calendar year. The total prevalence of ticks was reported to be 62.12%. According to study on breed, sex, age, and category, German spitz, male dogs, dogs under 1 year of age and stray dogs had the highest frequency of tick infestation. All throughout the year, tick infestations were seen, with the monsoon season seeing the highest frequency. Based on 16S rRNA gene amplification and sequence analysis, molecular identification revealed that all isolated ticks were members of the Rhipicephalus sanguineus species. Using a subset of the 16S rRNA gene, phylogenetic analysis revealed that R. sanguineus (OR244468.1) from Agartala (TrRS-PB) was part of the same clade as isolates from Kerala and Assam.

Microbial communities and functions are structured by vertical geochemical zones in a northern peatland

Northern peatlands are important carbon pools; however, differences in the structure and function of microbiomes inhabiting contrasting geochemical zones within these peatlands have rarely been emphasized. Using 16S rRNA gene sequencing, metagenomic profiling, and detailed geochemical analyses, we investigated the taxonomic composition and genetic potential across various geochemical zones of a typical northern peatland profile in the Changbai Mountains region (Northeastern China). Specifically, we focused on elucidating the turnover of organic carbon, sulfur (S), nitrogen (N), and methane (CH4). Three geochemical zones were identified and characterized according to porewater and solid-phase analyses: the redox interface (<10 cm), shallow peat (10–100 cm), and deep peat (>100 cm). The redox interface and upper shallow peat demonstrated a high availability of labile carbon, which decreased toward deeper peat. In deep peat, anaerobic respiration and methanogenesis were likely constrained by thermodynamics, rather than solely driven by available carbon, as the acetate concentrations reached 90 μmol·L−1. Both the microbial community composition and metabolic potentials were significantly different (p < 0.05) among the redox interface, shallow peat, and deep peat. The redox interface demonstrated a close interaction between N, S, and CH4 cycling, mainly driven by Thermodesulfovibrionia, Bradyrhizobium, and Syntrophorhabdia metagenome-assembled genomes (MAGs). The archaeal Bathyarchaeia were indicated to play a significant role in the organic carbon, N, and S cycling in shallow peat. Although constrained by anaerobic respiration and methanogenesis, deep peat exhibited a higher metabolic potential for organic carbon degradation, primarily mediated by Acidobacteriota. In terms of CH4 turnover, subsurface peat (10–20 cm) was a CH4 production hotspot, with a net turnover rate of ∼2.9 nmol·cm−3·d−1, while the acetoclastic, hydrogenotrophic, and methylotrophic methanogenic pathways all potentially contributed to CH4 production. The results of this study improve our understanding of biogeochemical cycles and CH4 turnover along peatland profiles.

Cellulolytic characterization of the rumen-isolated Acinetobacter pittii ROBY and design of a potential controlled-release drug delivery system

A novel cellulolytic bacterial strain, ROBY, was isolated from a bovine rumen sample using the enrichment culture method. This isolate was found to be Acinetobacter pittii, with >99 % similarity according to 16S rRNA gene sequence analysis. The potential use of this strain in combination with doxorubicin (Dox)-integrated cellulose nanoparticles (Dox-CNPs) was evaluated as a proof-of-concept study for the further development of this approach as a novel controlled-release drug delivery strategy. The isolate can utilize CNPs as the sole carbon source for growth and degrade both Dox-CNPs and empty CNPs with high efficiency. Extracellular cellulases isolated from bacteria may also be used to trigger Dox release. The results also demonstrated that the release of Dox into the environment due to nanoparticle degradation in the samples incubated with Dox-CNPs significantly affected bacterial cell viability (∼75 % decrease), proving the release of Dox due to bacterial cellulase activity and suggesting the great potential of this approach for further development.

Adaptability of the gut microbiota of the German cockroach Blattella germanica to a periodic antibiotic treatment

High-throughput sequencing studies have shown that diet or antimicrobial treatments impact animal gut microbiota equilibrium. However, properties related to the gut microbial ecosystem stability, such as resilience, resistance, or functional redundancy, must be better understood. To shed light on these ecological processes, we combined advanced statistical methods with 16 S rRNA gene sequencing, functional prediction, and fitness analyses in the gut microbiota of the cockroach Blattella germanica subject to three periodic pulses of the antibiotic (AB) kanamycin (n=512). We first confirmed that AB did not significantly affect cockroaches' biological fitness, and gut microbiota changes were not caused by insect physiology alterations. The sex variable was examined for the first time in this species, and no statistical differences in the gut microbiota diversity or composition were found. The comparison of the gut microbiota dynamics in control and treated populations revealed that (1) AB treatment decreases diversity and completely disrupts the co-occurrence networks between bacteria, significantly altering the gut community structure. (2) Although AB also affected the genetic composition, functional redundancy would explain a smaller effect on the functional potential than on the taxonomic composition. (3) As predicted by Taylor's law, AB generally affected the most abundant taxa to a lesser extent than the less abundant taxa. (4) Taxa follow different trends in response to ABs, highlighting "resistant taxa," which could be critical for community restoration. (5) The gut microbiota recovered faster after the three AB pulses, suggesting that gut microbiota adapts to repeated treatments.