Polish journal of microbiology最新文献

Previous research has demonstrated a connection between an unbalanced gut microbiome (GM) and lung diseases, suggesting that gut bacteria may affect lung health through the "gut-lung" axis. However, the direct connection between GM and pulmonary embolism (PE) is unclear. Mendelian randomization studies were used to investigate GM's genetic relationship with PE. A total of 18,340 independent genewide association studies (GWAS) yielded single nucleotide polymorphisms (SNPs) linked to the GM, which were then used as instrumental variables in a multiple regression analysis (MR) to examine the effect of GM on the risk of PE within the IEU Open GWAS project, which included 2,118 PE cases and 359,076 controls. The principal analytical methodology utilized in this research was inverse variance weighting (IVW), complemented by assessments for pleiotropy and heterogeneity to confirm the results' resilience. The findings of this study are predominantly derived from the IVW method, providing evidence for causal associations between four distinct genera of GM and the risk of PE. Specifically, our analysis suggests that Slackia (p = 0.031), Oscillospira (p = 0.038), Bacteroides (p = 0.032), and Clostridium sensu stricto 1 (p = 0.049) may be linked to a decreased likelihood of developing PE. Importantly, our analysis yielded no evidence of heterogeneity or pleiotropy. In this MR study, we have established through genetic analysis that specific GM are significantly involved in the development of PE, underscoring the connection between the gut-lung axis and suggesting avenues for future research into the impact of GM on PE.

Gut microbiota acts on the lungs through the gut-lung axis and play an important role in lung diseases. However, there are no reports on the gut microbiota characteristics in patients with invasive pulmonary aspergillosis (IPA). We aimed to analyze changes in gut microbiota in IPA patients, correlate these changes with clinical indicators and disease prognosis, and explore the application value of these characteristic changes in diagnosing IPA. The objective was to provide a theoretical basis for preventing and treating individual immunity. We conducted metagenomic next-generation sequencing of fecal samples from 43 patients with IPA and 31 healthy controls to analyze changes in the gut microbiota of these patients. We also built a random forest model for diagnosing IPA based on the gut microbiota. Compared to healthy controls, IPA patients showed a decrease in gut microbiota diversity and metabolic levels. Changes in the microbiota were characterized by a significant reduction in anti-inflammatory species that produce short-chain fatty acids, such as Faecalibacterium, Blautia, Roseburia, Phocaeicola, and Bacteroides. In contrast, opportunistic pathogens, such as Enterococcus, Corynebacterium, Escherichia, Staphylococcus, Haemophilus, and Finegoldia, were significantly enriched. The classification model based on Clostridium fessum, Blautia wexlerae, Streptococcus pseudopneumoniae, Corynebacterium striatum, and Faecalibacterium prausnitzii showed high value in distinguishing patients with IPA from healthy controls. Patients with IPA exhibit gut microbiota imbalance. The gut microbiota can serve as a biomarker that helps in diagnosing IPA. Our findings support the potential use of gut microbiota as a target for IPA prevention and treatment.

Gelatine-processing wastewater contains much residual sludge due to its high calcium ion concentration and chemical oxygen demand. In this study, N3-4, a microbial strain with excellent calcium tolerance capacity, was screened and identified as Virgibacillus pantothenticus using morphological observation, physiological and biochemical testing, and 16S rRNA sequence analysis. Its growth characteristics were investigated, and the maximum adsorption of calcium reached 572.43 μg/g under the optimal conditions (contact time, 72.68 min; biomass dosage, 1.3 g/l; initial calcium concentration, 142.01 mg/l). Conditions were optimized using response surface methodology and structural characterization. The structure of the bacterial pellets was altered from flat to rough, accompanied by bulges and sediments after Ca²⁺ treatment, according to structural characterization. Energy-dispersive X-ray spectroscopy of the bacterial precipitates under calcium(II) treatment revealed the immobilization of Ca²⁺ species on the bacterial cell surface. The results indicate that -OH, -NH₂, C≡C, C=O, -CH₂, -C-O-, and -C-N groups play a significant role in calcium dispersion on the surface of V. pantothenticus.

Amylase has numerous applications in the processing food sector, including brewing, animal feed, baking, fruit juice manufacturing, starch syrups, and starch liquefaction. Practical applications have been the primary focus of recent research on novel properties of bacterial α-amylases. Many amylolytic-active bacterial isolates were obtained from samples of organic-rich, salinity-rich soil. Morphological and 16S rRNA gene sequence studies clearly revealed that the organism belongs to Bacillus sp. and was named Bacillus cereus strain GL2 (PP463909.1 (When pH 6.0, 45°C, and 12 hours of incubation were met the optimal growth conditions for the strain produced the highest amount of α-amylase activity. B. cereus strain GL2 α-amylase isoenzyme was purified to homogeneity using Sephacryl™ S-200 chromatography and ammonium sulfate precipitation. The electrophoretic molecular weight of B. cereus α-amylase was 58 kDa. The optimal pH and temperature for measuring α-amylase activity were 50°C and 6.0, respectively. α-Amylase did not change at 50°C. The purified enzyme improves bread texture by reducing stiffness while improving cohesiveness and flexibility. Purified α-amylase was added to the flour, which improved the rheological properties and overall bread quality. As a result, the α-amylase from B. cereus strain GL2 can be used to promote bread-making.

Globally, the infection rate of carbapenem-resistant Klebsiella pneumoniae (CRKP) producing OXA-48-like carbapenemase is increasing, posing a significant public health threat due to its high antibiotic resistance. Between December 2019 and April 2023, ten CRKP strains carrying the OXA-48-like carbapenemase were isolated from inpatients at the First Affiliated Hospital of Kunming Medical University. Wholegenome sequencing (WGS) revealed that all strains carried the OXA-232 gene, a variant of OXA-48-like, located on the non-conjugative ColKP3 plasmid. Sequence typing identified nine strains as ST231 and one as ST11. The ST231 strains carried common virulence genes, including yersiniabactin (ybtA, fyuA, irp2) and aerobactin (iucABCD, iutA), while the ST11 strain carried high-virulence genes (rmpA, rmpA2, peg-344) as well as KPC-2 and OXA-232 carbapenemase genes on separate plasmids, suggesting that CRKP can harbor multiple plasmids with carbapenemase genes. Sequence typing of 264 global ST231 CRKP isolates (n = 264) showed a distinct clonal relationship between our strains and Indian CRKP isolates, indicating potential cross-border transmission. The virulence potential and immune response of the ST231 strains were assessed using a mouse respiratory infection model. The concentrations of inflammatory factors CCL2/MCP-1, IL-6, and TNF-α in the alveolar lavage fluid and blood of the model mice were detected. Combined with the pathological analysis of lung and liver tissues, it reveals variability in virulence and immune response despite carrying identical resistance and virulence genes. This underscores the urgent need for monitoring and tailored public health strategies to combat the global spread of drug-resistant strains.

For the first time, this study reports extracellular uricase enzyme isolation and characterization from strain UR1 of Alcaligenes spp. from Western Saudi Arabia. The strain efficiently produced highly active extracellular uricase for therapeutic applications. It offers a simplified enzyme purification approach rather than complicated intracellular enzyme purification from other microbes. Strain UR1 exhibited significantly higher uricase synthesis potential [916 U/mg (specific activities) and 275 U/ml (volume)]. The study optimized the conditions (37°C and pH 7.4) for 10% enhanced uricase production in the BT medium where sucrose served as the carbon source. Uricase enzyme remained stable at various pH levels (5-9) up to 50°C, however, the optimal activity was noted at 40°C and pH 7.5. The strain was sensitive to EDTA-like inhibitors. Ca²⁺ improved the strain activity, which could yield potent formulations for clinical and industrial applications. This novel aspect presents Alcaligenes spp. strain UR1 as a promising candidate for the treatment of hyperuricemia and gout. It offers an efficient and inexpensive alternative for uricase synthesis at the industrial scale. These findings encourage further investigations regarding genetic aspects of uricase for improved bioprocessing and therapeutic applications.

Infection with Helicobacter pylori is the major causative factor of chronic gastritis, peptic ulcer, gastric cancer, and other diseases. Gastric mucosal epithelial injury characterized by abnormal apoptosis, oxidative stress, and inflammation is a crucial mechanism of H. pylori infection. Hyperoside (HYP) is a flavonol glycoside derived from many herbal plants, which exhibits potent anti-apoptotic, antioxidant, and anti-inflammatory properties. Our research explored whether it exerts protective effects on H. pylori-infected human gastric epithelial cells. GES-1 cells were first treated for 24 h with HYP (0, 10, 20, 40, 80, 100, or 120 μM) to determine the cytotoxicity of HYP. Subsequently, GES-1 cells were pre-treated for 4 h with HYP (80 μM), followed by exposure to H. pylori for 24 h. CCK-8 assay, flow cytometry assay, ELISA, RT-qPCR, DCFH-DA staining, the commercial assay kits, immunofluorescence staining, and western blotting were used to assess cell viability, cell apoptosis, pro-inflammatory cytokine levels, oxidative stress marker levels, and Nrf2/HO-1 signaling-related molecule levels. The Nrf2 inhibitor ML385 was employed to verify the beneficial role of Nrf2 activation in HYP-mediated GES-1 cell injury induced by H. pylori. The results showed that HYP pre-treatment reversed H. pylori-induced cell apoptosis, inflammation, and oxidative stress in GES-1 cells. Furthermore, HYP downregulated Nrf2, HO-1, and NQO1 protein levels in H. pylori-infected GES-1 cells. ML385 overturned the protective effects of HYP against H. pylori-induced GES-1 cell apoptosis, inflammation, and oxidative stress. In conclusion, HYP protects gastric epithelial cells against H. pylori-induced cell injury by activating the Nrf2/HO-1 pathway.

Benzene is a pervasive contaminant and human carcinogen. Its remediation from environmental resources using conventional procedures has always been challenging due to high cost and incomplete benzene degradation. The present study was designed to explore highly efficient bacteria with benzene degrading potential from tannery industry soil, which might be used as an alternative to these conventional benzene removal remedies. Bacterial isolation was performed using benzene (80 μl/1,000 ml) supplemented with minimal salt media (MSM). Characterization of isolates was carried out by performing growth curve analysis, Gram staining, biochemical characterization via Remel RapID™ NF PLUS System (Thermo Scientific™, Thermo Fisher Scientific, Inc., USA), antibiotic sensitivity profiling, 16S rRNA gene sequencing, benzene removal efficiency estimation assay, FTIR, and GC-MS profiling. Five bacteria isolated in the present study were identified as Paracoccus aestuarii PUB1, Bacillus tropicus PUB2, Bacillus albus PUB3, Bacillus subtilis PUB4, and Bacillus cereus PUB6. All of these fast-growing bacteria were Gram-positive except P. aestuarii PUB1. Maximum benzene removal efficiency (30 mg/l per 25 h) was found in B. tropicus PUB2. Comparing the FTIR spectra of bacterial culture supernatant versus control revealed the peaks shifting corresponding to benzene ring bonds breaking. GC-MS analysis identified the metabolic intermediates from benzoate methylation and benzaldehyde pathways. These bacteria can be employed for benzene degradation via enzyme-based nanoparticle synthesis or cloning of relevant genes in eco-friendly expression systems.

Antimicrobial resistance poses a significant threat to global health, with colistin as a last-resort antibiotic against multidrug-resistant (MDR) microorganisms. The present study aimed to investigate the dynamics of antimicrobial susceptibility patterns and risk factors associated with infections caused by colistin-resistant bacteria in the Northern region of Haryana, India. Clinical samples (n = 12,652) collected from a single hospital in Haryana were subjected to microbiological analysis for five months. Among the total samples (n = 12,652) processed, 24% (n = 3,061) showed growth of pathogenic bacteria. Within the Gram-negative isolates, 56% (n = 1,242) were non-MDR, while 44% (n = 995) were MDR. Among MDR isolates (n = 995), 6% (n = 57) showed resistance to colistin. Notably, Pseudomonas spp. (12%, n = 19) and Acinetobacter spp. (11%, n = 8) demonstrated the highest resistance to colistin, followed by Klebsiella spp. (5%, n = 13), Escherichia coli (3%, n = 16), and Citrobacter freundii (1%, n = 1), respectively. The study revealed significant associations between the level of education (demographic variable) and the occurrence of colistin resistance. Prolonged hospital stays (> 5 days) and specific comorbidities, including diabetes (p < 0.01) and chronic obstructive pulmonary disease (p < 0.01), were identified as risk factors for colistin-resistant infections. Importantly, none of the colistin-resistant bacteria harbored mcr genes, suggesting alternative resistance mechanisms. Antibiotic sensitivity analysis indicated promising efficacy of antibiotics such as amikacin and gentamicin against colistin-resistant strains, though with variations across bacterial species. In summary, the study emphasizes the urgent need for enhanced surveillance, infection control protocols, and antimicrobial stewardship programs in healthcare settings to minimize the dissemination of MDR and colistin-resistant bacteria.

Alteration of the gut microbiota (GM) is associated with various diseases, including colorectal cancer (CRC). With the development of next-generation sequencing techniques, metagenomic sequencing, along with metabolic function and antibiotic-resistant gene analyses, has been used to investigate differences in GM between CRC patients and healthy controls. Fecal samples were obtained from seven CRC patients and six healthy subjects, and the sequencing data were analyzed for similarity, a-diversity, principal component analysis (PCA), and linear discriminant analyses (LDA). Regarding Actinobacteria, 3 orders, 5 families, 9 genera, and 19 species were identified with no differences between the CRC and control groups, while the levels of Bifidobacterium bifidum and Bifidobacterium dentium were higher, and the level of Bifidobacterium breve was lower in the CRC group compared to the healthy controls (p = 0.053). Otherwise, 2 genera (Leuco-nostoc and Salmonella) and 7 species of bacteria (Parabacteroides merdae, Alistipes shahii, Alistipes finegoldii, Clostridium nexile, Salmonella enterica, unclassified Salmonella, Enterobacter cloacae) were found to be significantly differently distributed between CRC patients and healthy controls. PCA-LDA successfully classified these 2 groups with satisfactory accuracy (84.52% for metabolic function and 77.38% for resistant genes). These findings underscore the potential of GM as a diagnostic tool for CRC, offering a promising avenue for non-invasive screening and risk assessment. The identification of specific microbial signatures, particularly those linked to metabolic functions and resistance traits, could open new doors for understanding the role of the microbiome in CRC progression and treatment resistance.