TY - JOUR AB - BACKGROUND: The gut microbiome has been identified as a pivotal factor in ulcerative colitis (UC), given its role as the main reservoir of microbes in the body. This community of microorganisms, present in variable concentrations in the digestive tract, makes a wide range of beneficial roles for the host. However, the role of the gut microbiome in patients with refractory UC is still significant, so this study aimed to further investigate the role of these bacteria in patients with refractory UC. METHODS: This case-control study was conducted on stool samples from four distinct groups: the first group comprised new patients diagnosed with ulcerative colitis (all of them had responded to treatment after follow-up) (N = 24); the second group consisted of patients with treatment-resistant ulcerative colitis (N = 23); the third group included first-degree relatives of group 1 patients (N = 24); and the fourth group consisted of first-degree relatives of group 2 patients (N = 23). The research tools employed in this study included a questionnaire, quantitative real-time PCR (qPCR) test, and culture on stool samples. RESULT: The mean age of patients in groups 1 and 2 was 45.88 ± 18.51 and 41.30 ± 13.01 years, while the mean age of controls in groups 3 and 4 was 37.29 ± 9.62 and 40.96 ± 13.01 years, respectively. Stool culture results for pathogenic bacteria were negative in all four groups. The of history of consuming dairy products containing probiotics was highest in Group 1, with 22 (91.67%) subjects, while the lowest was observed in Group 3, with 16 (66.67%). The highest history of self-administered antibiotic use was observed in Group 2, with 13 cases (56.52%), while the lowest was noted in Group 3, with 4 cases (16.67%). The findings indicated a statistically significant relationship (P < 0.05) between Groups 2 and 4 with respect to the E. coli and Bifidobacterium ssp. microbial population. Additionally, a significant relationship was identified between the Lactobacillus ssp., Bifidobacterium ssp., and Bacteroides ssp. microbial community between groups 1 and 2 (P < 0.05). CONCLUSION: The findings of this study demonstrated that several intestinal microbiomes have a substantial impact on the management of ulcerative colitis. The results of this study suggest that by comparing the gut microbiome of treatment-resistant and individuals newly diagnosed with ulcerative colitis, we can gain a better understanding of microbiome differences that may influence treatment outcomes. The results of this study may also lead to the identification of new therapeutic strategies that are based on regulating the gut microbiome. These strategies could include the use of fecal microbiome transplantation (FMT), probiotics, prebiotics, or specific bacteria-based therapies. AU - Ahmadi, A.* AU - Shokoohizadeh, L.* AU - Sheikhesmaili, F.* AU - Mirzaei, M.K. AU - Mohammadi, A.* AU - Nikkhoo, B.* AU - Khodaei, H.* AU - Alikhani, M.Y.* AU - Yousefimashouf, R.* C1 - 74220 C2 - 57399 CY - Campus, 4 Crinan St, London N1 9xw, England TI - Gut microbiomes and treatment-resistant ulcerative colitis: A case-control study using qPCR. JO - BMC Microbiol. VL - 25 IS - 1 PB - Bmc PY - 2025 ER - TY - JOUR AB - BACKGROUND: Growing evidence suggests that soil microbes can improve plant fitness under drought. However, in potato, the world's most important non-cereal crop, the role of the rhizosphere microbiome under drought has been poorly studied. Using a cultivation independent metabarcoding approach, we examined the rhizosphere microbiome of two potato cultivars with different drought tolerance as a function of water regime (continuous versus reduced watering) and manipulation of soil microbial diversity (i.e., natural (NSM), vs. disturbed (DSM) soil microbiome). RESULTS: Water regime and soil pre-treatment showed a significant interaction with bacterial community composition of the sensitive (HERBST) but not the resistant cultivar (MONI). Overall, MONI had a moderate response to the treatments and its rhizosphere selected Rhizobiales under reduced watering in NSM soil, whereas Bradyrhizobium, Ammoniphilus, Symbiobacterium and unclassified Hydrogenedensaceae in DSM soil. In contrast, HERBST response to the treatments was more pronounced. Notably, in NSM soil treated with reduced watering, the root endophytic fungus Falciphora and many Actinobacteriota members (Streptomyces, Glycomyces, Marmoricola, Aeromicrobium, Mycobacterium and others) were largely represented. However, DSM soil treatment resulted in no fungal taxa and fewer enrichment of these Actinobacteriota under reduced watering. Moreover, the number of bacterial core amplicon sequence variants (core ASVs) was more consistent in MONI regardless of soil pre-treatment and water regimes as opposed to HERBST, in which a marked reduction of core ASVs was observed in DSM soil. CONCLUSIONS: Besides the influence of soil conditions, our results indicate a strong cultivar-dependent relationship between the rhizosphere microbiome of potato cultivars and their capacity to respond to perturbations such as reduced soil moisture. Our study highlights the importance of integrating soil conditions and plant genetic variability as key factors in future breeding programs aiming to develop drought resistance in a major food crop like potato. Elucidating the molecular mechanisms how plants recruit microbes from soil which help to mitigate plant stress and to identify key microbial taxa, which harbour the respective traits might therefore be an important topic for future research. AU - Martins, R.B. AU - Siani, R. AU - Treder, K.* AU - Michałowska, D.* AU - Radl, V. AU - Pritsch, K. AU - Schloter, M. C1 - 68884 C2 - 53742 CY - Campus, 4 Crinan St, London N1 9xw, England TI - Cultivar-specific dynamics: unravelling rhizosphere microbiome responses to water deficit stress in potato cultivars. JO - BMC Microbiol. VL - 23 IS - 1 PB - Bmc PY - 2023 ER - TY - JOUR AB - BACKGROUND: Obesity, metabolic disease and some psychiatric conditions are associated with changes to relative abundance of bacterial species and specific genes in the faecal microbiome. Little is known about the impact of pharmacologically induced weight loss on distinct microbiome species and their respective gene programs in obese individuals. METHODOLOGY: Using shotgun metagenomics, the composition of the microbiome was obtained for two cohorts of obese female Wistar rats (n = 10-12, total of 82) maintained on a high fat diet before and after a 42-day treatment with a panel of four investigatory or approved anti-obesity drugs (tacrolimus/FK506, bupropion, naltrexone and sibutramine), alone or in combination. RESULTS: Only sibutramine treatment induced consistent weight loss and improved glycaemic control in the obese rats. Weight loss was associated with reduced food intake and changes to the faecal microbiome in multiple microbial taxa, genes, and pathways. These include increased β-diversity, increased relative abundance of multiple Bacteroides species, increased Bacteroides/Firmicutes ratio and changes to abundance of genes and species associated with obesity-induced inflammation, particularly those encoding components of the flagellum and its assembly. CONCLUSIONS: Sibutramine-induced weight loss in obese rats is associated with improved metabolic health, and changes to the faecal microbiome consistent with a reduction in obesity-induced bacterially-driven inflammation. AU - Raineri, S.* AU - Sherriff, J.A.* AU - Thompson, K.S.J.* AU - Jones, H.* AU - Pfluger, P.T. AU - Ilott, N.E.* AU - Mellor, J.* C1 - 64804 C2 - 52498 TI - Pharmacologically induced weight loss is associated with distinct gut microbiome changes in obese rats. JO - BMC Microbiol. VL - 22 IS - 1 PY - 2022 ER - TY - JOUR AB - BACKGROUND: P. aeruginosa is the primary source of hospital-acquired infections. Unfortunately, antibiotic resistance is growing to precariously high levels, making the infections by this pathogen life-threatening and hard to cure. One possible alternative to antibiotics is to use phages. However, the isolation of phages suitable for phage therapy- be lytic, be efficient, and have a broad host range -against some target bacteria has proven difficult. To identify the best places to look for these phages against P. aeruginosa we screened hospital sewages, soils, and rivers in two cities. RESULTS: We isolated eighteen different phages, determined their host range, infection property, and plaque morphology. We found that the sewage and sewage-contaminated environments are the most reliable sources for the isolation of Pseudomonas phages. In addition, phages isolated from hospital sewage showed the highest efficiency in lysing the bacteria used for host range determination. In contrast, phages from the river had larger plaque size and lysed bacteria with higher levels of antibiotic resistance. CONCLUSIONS: Our findings provided additional support for the importance of sewage as the source of phage isolation. AU - Aghaee, B.L.* AU - Mirzaei, M.K. AU - Alikhani, M.Y.* AU - Mojtahedi, A.* C1 - 61959 C2 - 50537 CY - Campus, 4 Crinan St, London N1 9xw, England TI - Sewage and sewage-contaminated environments are the most prominent sources to isolate phages against Pseudomonas aeruginosa. JO - BMC Microbiol. VL - 21 IS - 1 PB - Bmc PY - 2021 ER - TY - JOUR AB - Background: Bloom-forming cyanobacteria cause toxic algae outbreaks in lakes and reservoirs. We aimed to explore and quantify mutation events occurring within the large mcy gene cluster (55 kbp) encoding microcystin (MC) biosynthesis that inactivate MC net production. For this purpose we developed a workflow to detect mutations in situ occurring anywhere within the large mcy gene cluster as amplified from one single filament of the red-pigmented cyanobacterium Planktothrix rubescens. From five lakes of the Alps eight hundred Planktothrix filaments were isolated and each individual filament was analyzed for mutations affecting the mcy genes. Results: Mutations inactivating MC synthesis were either through an insertion element ISPlr1 or the partial deletion of mcy genes. Neutral mutations not affecting MC biosynthesis occurred within two intergenic spacer regions, either through the insertion of a Holliday-junction resolvase RusA or ISPlr1. Altogether, the insertions affected a few mcy genes only and their location was correlated with regions similar to repetitive extragenic palindromic DNA sequences (REPs). Taking all of the filaments together, the mutations leading to the inactivation of MC synthesis were more rare (0.5-6.9 %), when compared with the neutral mutations (7.5-20.6 %). On a spatial-temporal scale the ratio of MC synthesis-inactivating vs. neutral mutations was variable, e.g., the filament abundance carrying partial deletion of mcyD (5.2-19.4 %) and/or mcyHA (0-7.3 %) exceeded the abundance of neutral mutations. Conclusions: It is concluded that insertion events occurring within the Planktothrix mcy gene cluster are predictable due to their correlation with REPs. The frequency of occurrence of the REPs within the mcy gene cluster of Planktothrix relates to the rather common mutation of mcy genes in Planktothrix. Spatial-temporal variable conditions may favor the emergence of partial mcy deletion mutants in Planktothrix, in particular a higher proportion of genotypes resulting in inactivation of MC synthesis might be caused by increased ISPlr1 activity. AU - Chen, Q.* AU - Christiansen, G.* AU - Deng, L. AU - Kurmayer, R.* C1 - 48073 C2 - 39884 CY - London TI - Emergence of nontoxic mutants as revealed by single filament analysis in bloom-forming cyanobacteria of the genus Planktothrix. JO - BMC Microbiol. VL - 16 IS - 1 PB - Biomed Central Ltd PY - 2016 ER - TY - JOUR AB - UNLABELLED: ABSTRACT: BACKGROUND: Hepatitis B virus (HBV), because of its error-prone viral polymerase, has a high mutation rate leading to widespread substitutions, deletions, and insertions in the HBV genome. Deletions may significantly change viral biological features complicating the progression of liver diseases. However, the clinical conditions correlating to the accumulation of deleted mutants remain unclear. In this study, we explored HBV deletion patterns and their association with disease status and antiviral treatment by performing whole genome sequencing on samples from 51 hepatitis B patients and by monitoring changes in deletion variants during treatment. Clone sequencing was used to analyze preS regions in another cohort of 52 patients. RESULTS: Among the core, preS, and basic core promoter (BCP) deletion hotspots, we identified preS to have the highest frequency and the most complex deletion pattern using whole genome sequencing. Further clone sequencing analysis on preS identified 70 deletions which were classified into 4 types, the most common being preS2. Also, in contrast to the core and BCP regions, most preS deletions were in-frame. Most deletions interrupted viral surface epitopes, and are possibly involved in evading immuno-surveillance. Among various clinical factors examined, logistic regression showed that antiviral medication affected the accumulation of deletion mutants (OR = 6.81, 95% CI = 1.296 ~ 35.817, P = 0.023). In chronic carriers of the virus, and individuals with chronic hepatitis, the deletion rate was significantly higher in the antiviral treatment group (Fisher exact test, P = 0.007). Particularly, preS2 deletions were associated with the usage of nucleos(t)ide analog therapy (Fisher exact test, P = 0.023). Dynamic increases in preS1 or preS2 deletions were also observed in quasispecies from samples taken from patients before and after three months of ADV therapy. In vitro experiments demonstrated that preS2 deletions alone were not responsible for antiviral resistance, implying the coordination between wild type and mutant strains during viral survival and disease development. CONCLUSIONS: We present the HBV deletion distribution patterns and preS deletion substructures in viral genomes that are prevalent in northern China. The accumulation of preS deletion mutants during nucleos(t)ide analog therapy may be due to viral escape from host immuno-surveillance. AU - Zhang, D.* AU - Dong, P.* AU - Zhang, K. AU - Deng, L.* AU - Bach, C. AU - Chen, W.* AU - Li, F.* AU - Protzer, U. AU - Ding, H.* AU - Zeng, C.* C1 - 22441 C2 - 30860 TI - Whole genome HBV deletion profiles and the accumulation of preS deletion mutant during antiviral treatment. JO - BMC Microbiol. VL - 12 PB - Biomed Central PY - 2012 ER -