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1.
Imeta ; 3(3): e202, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38898988

ABSTRACT

The evaluation of pathobiome strains should be conducted at the strain level, involving the identification of the functional genes, while considering the impact of ecological niche and drug interactions. The safety, efficacy, and quality management of live biotherapeutic products (LBPs), especially pathobiome strains, have certain peculiarities. Promising development methods include the recombinant LBP and active metabolites.

4.
Microbiol Spectr ; 11(3): e0415222, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37093057

ABSTRACT

Fecal microbiota transplantation (FMT) can induce clinical remission in ulcerative colitis (UC) patients. Enemas, nasoduodenal tubes, and colonoscopies are the most common routes for FMT administration. However, there is a lack of definitive evidence regarding the effectiveness of capsulized FMT treatment in UC patients. In this study, we administered capsulized FMT to 22 patients with active UC to assess the efficiency of capsulized FMT and determine the specific bacteria and metabolite factors associated with the response to clinical remission. Our results showed that the use of capsulized FMT was successful in the treatment of UC patients. Capsulized FMT induced clinical remission and clinical response in 57.1% (12 of 21) and 76.2% (16 of 21) of UC patients, respectively. Gut bacterial richness was increased after FMT in patients who achieved remission. Patients in remission after FMT exhibited enrichment of Alistipes sp. and Odoribacter splanchnicus, along with increased levels of indolelactic acid. Patients who did not achieve remission exhibited enrichment of Escherichia coli and Klebsiella and increased levels of biosynthesis of 12,13-DiHOME (12,13-dihydroxy-9Z-octadecenoic acid) and lipopolysaccharides. Furthermore, we identified a relationship between specific bacteria and metabolites and the induction of remission in patients. These findings may provide new insights into FMT in UC treatment and provide reference information about therapeutic microbial manipulation of FMT to enhance its effects. (This study has been registered at ClinicalTrails.gov under registration no. NCT03426683). IMPORTANCE Fecal microbiota transplantation has been successfully used in patients. Recently, capsulized FMT was reported to induce a response in patients with UC. However, limited patients were enrolled in such studies, and the functional factors of capsulized FMT have not been reported in the remission of patients with UC. In this study, we prospectively recruited patients with UC to receive capsulized FMT. First, we found that capsulized FMT could induce clinical remission in 57.1% of patients and clinical response in 76.2% after 12 weeks, which was more acceptable. Second, we found a relationship between the decrease of opportunistic pathogen and lipopolysaccharide synthesis in patients in remission after capsulized FMT. We also identified an association between specific bacteria and metabolites and remission induction in patients after capsulized FMT. These findings put forward a possibility for patients to receive FMT at home and provide reference information about therapeutic microbial manipulation of FMT to enhance its effects.


Subject(s)
Colitis, Ulcerative , Communicable Diseases , Gastrointestinal Microbiome , Humans , Bacteria , Colitis, Ulcerative/therapy , Colitis, Ulcerative/microbiology , Fecal Microbiota Transplantation/methods , Feces/microbiology , Treatment Outcome
5.
Microbiol Spectr ; 11(1): e0215921, 2023 02 14.
Article in English | MEDLINE | ID: mdl-36472435

ABSTRACT

Fecal microbiota transplantation (FMT) targeting gut microbiota has recently been applied to the treatment of ulcerative colitis (UC). However, preliminary trials showed that only a subset of patients responded to FMT, and the heterogeneity in donor gut microbiota probably played important roles in patients' responses, implying the significance of matching an appropriate donor to a specified patient. We developed a strategy to build a donor-recipient matching model to guide rational donor selection for UC in FMT. We collected and uniformly reanalyzed 656 fecal 16S rRNA gene sequencing samples (350 from UC patients and 306 from healthy subjects) from 9 studies. Significantly lower α-diversity indexes were observed in UC patients by random effects model. Thirty-four bacterial genera and 34 predicted pathways were identified with significant odds ratios and classification potentials for UC patients. Based on six bacterial indicators, including richness, overall distance, genera, and pathways (beneficial and harmful), the analytic hierarchy process-based donor-recipient matching model was set to rank and select appropriate donors for patients with UC. Finally, the model showed favorable classification powers (>70%) for FMT effectiveness in two previous clinical trials. This study revealed the dysbiosis of fecal bacterial diversity, composition, and predicted pathways of patients with UC by meta-analysis and hereby developed a donor-recipient matching strategy to guide donor selection for UC in FMT. This strategy can also be applied to other diseases associated with gut microbiota. IMPORTANCE Modulation of gut microbiota by FMT from donors has been applied to the treatment of UC and yielded variable effectiveness in clinical trials. One possibility is that this variable effectiveness was related to donor selection, as a patient's response to FMT may rely on the capability of the used donor's microbiota to restore the specific gut disturbances of the patient. However, the biggest issues on the practical level are what should be considered in the selection process and how to set up such a donor-recipient matching model. In this study, we presented a bacterial profile-based donor-recipient matching strategy to guide donor selection for UC in FMT by first meta-analysis of 656 fecal 16S rRNA gene sequencing samples from 9 studies to identify significant indicators and then setting up the model by an analytic hierarchy process. The applicability and accuracy of this model were verified in the data sets from two previous FMT clinical studies. Our data indicate that the donor-recipient matching model built in this study enables researchers to rationally select donors for UC patients in FMT clinical practice, although it needs more samples and prospective trials for validation. The strategy adopted in this study to leverage existing data sets to build donor-recipient matching models for precision FMT is feasible for other diseases associated with gut microbiota.


Subject(s)
Colitis, Ulcerative , Fecal Microbiota Transplantation , Humans , Colitis, Ulcerative/therapy , Colitis, Ulcerative/microbiology , Prospective Studies , RNA, Ribosomal, 16S/genetics , Analytic Hierarchy Process , Donor Selection , Treatment Outcome , Feces/microbiology , Bacteria/genetics
7.
J Ovarian Res ; 15(1): 117, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36303234

ABSTRACT

To characterize the gut bacteriome, mycobiome and serum metabolome profiles in polycystic ovary syndrome (PCOS) patients with normal/overweight individuals and evaluate a potential microbiota-related diagnostic method development for PCOS, 16S rRNA and ITS2 gene sequencing using 88 fecal samples and 87 metabolome analysis from serum samples are conducted and PCOS classifiers based on multiomics markers are constructed. There are significant bacterial, fungal community and metabolite differences among PCOS patients and healthy volunteers with normal/overweight individuals. Healthy individuals with overweight/obesity display less abnormal metabolism than PCOS patients and uniquely higher abundance of the fungal genus Mortierella. Nine bacterial genera, 4 predicted pathways, 11 fungal genera and top 30 metabolites are screened out which distinguish PCOS from healthy controls, with AUCs of 0.84, 0.64, 0.85 and 1, respectively. The metabolite-derived model is more accurate than the microbe-based model in discriminating normal BMI PCOS (PCOS-LB) from normal BMI healthy (Healthy-LB), PCOS-HB from Healthy-HB. Featured bacteria, fungi, predicted pathways and serum metabolites display higher associations with free androgen index (FAI) in the cooccurrence network. In conclusion, our data reveal that hyperandrogenemia plays a central role in the dysbiosis of intestinal microecology and the change in metabolic status in patients with PCOS and that its effect exceeds the role of BMI. Healthy women with high BMI showed unique microbiota and metabolic features.The priority of predictive models in discriminating PCOS from healthy status in this study were serum metabolites, fungal taxa and bacterial taxa.


Subject(s)
Mycobiome , Polycystic Ovary Syndrome , Humans , Female , Overweight/complications , RNA, Ribosomal, 16S , Metabolome , Bacteria/genetics
9.
Front Cell Infect Microbiol ; 12: 1086885, 2022.
Article in English | MEDLINE | ID: mdl-36683707

ABSTRACT

Objective: Fecal microbiota transplantation (FMT) is a novel microbial treatment for patients with ulcerative colitis (UC). In this study, we performed a clinical trial of capsulized FMT in UC patients to determine the association between the gut fungal community and capsulized FMT outcomes. Design: This study recruited patients with active UC (N = 22) and healthy individuals (donor, N = 9) according to the criteria. The patients received capsulized FMT three times a week. Patient stool samples were collected before (week 0) and after FMT follow-up visits at weeks 1, 4, and 12. Fungal communities were analysed using shotgun metagenomic sequencing. Results: According to metagenomic analysis, fungal community evenness index was greater in samples collected from patients, and the overall fungal community was clustered among the samples collected from donors. The dominant fungi in fecal samples collected from donors and patients were Ascomycota and Basidiomycota. However, capsulized FMT ameliorated microbial fungal diversity and altered fungal composition, based on metagenomic analysis of fecal samples collected before and during follow-up visits after capsulized FMT. Fungal diversity decreased in samples collected from patients who achieved remission after capsulized FMT, similar to samples collected from donors. Patients achieving remission after capsulized FMT had specific enrichment of Kazachstania naganishii, Pyricularia grisea, Lachancea thermotolerans, and Schizosaccharomyces pombe compared with patients who did not achieve remission. In addition, the relative abundance of P. grisea was higher in remission fecal samples during the follow-up visit. Meanwhile, decreased levels of pathobionts, such as Candida and Debaryomyces hansenii, were associated with remission in patients receiving capsulized FMT. Conclusion: In the metagenomic analysis of fecal samples from donors and patients with UC receiving capsulized FMT, shifts in gut fungal diversity and composition were associated with capsulized FMT and validated in patients with active UC. We also identified the specific fungi associated with the induction of remission. ClinicalTrails.gov (NCT03426683).


Subject(s)
Colitis, Ulcerative , Fecal Microbiota Transplantation , Humans , Colitis, Ulcerative/therapy , Fecal Microbiota Transplantation/adverse effects , Feces/microbiology , Fungi/genetics , Remission Induction , Treatment Outcome
10.
Front Immunol ; 12: 774966, 2021.
Article in English | MEDLINE | ID: mdl-34745150

ABSTRACT

A mixed Chinese herbal formula, Xiao-Qing-Long-Decoction (XQLD), may contribute to sustained remission in allergic rhinitis (AR), but it is unknown which factors determine such long-term effect. Here, we aimed to identify bacterial signatures associated with sustained remission. To this end, samples from AR patients at four different times were analyzed to compare the dynamic bacterial community and structure shifts. Diversity indices Chao1 showed significant difference across different time (p<0.05), and the Kruskal-Wallis test identified that Dialister (OTU_31), Roseburia (OTU_36), Bacteroides (OTU_22), Bacteroides (OTU_2040), and Prevotella_9 (OTU_5) were the significant differential bacterial taxa (p<0.05). These distinctive genera were significantly associated with the change of AR clinical indices and the predicted functional pathways such as PPAR signaling pathway, peroxisome, and citrate cycle (TCA cycle) (p<0.05), indicating that they may be important bacterial signatures involving in the sustained remission in AR (p<0.05). Besides, lower Firmicutes/Bacteroidetes (F/B) ratio at 6 months follow-up may also contribute to the long-term remission of AR. No seriously adverse events and safety concerns were observed in this study. In conclusion, XQLD is a meaningful, long-term efficient and safe medication for AR treatment. The underlying mechanisms of sustained remission in AR after XQLD treatment may be associated with the dynamic alteration of featured gut bacteria taxa.


Subject(s)
Drugs, Chinese Herbal/adverse effects , Dysbiosis/diagnosis , Dysbiosis/etiology , Rhinitis, Allergic/complications , Adolescent , Adult , Biomarkers , Disease Management , Disease Susceptibility , Drugs, Chinese Herbal/therapeutic use , Female , Follow-Up Studies , Gastrointestinal Microbiome/drug effects , Humans , Male , Metagenome , Metagenomics/methods , Middle Aged , RNA, Ribosomal, 16S , Rhinitis, Allergic/drug therapy , Young Adult
11.
Front Immunol ; 12: 722206, 2021.
Article in English | MEDLINE | ID: mdl-34484230

ABSTRACT

Type 2 diabetes mellitus (T2DM) is a complex disorder comprehensively influenced by genetic and environmental risk, and research increasingly has indicated the role of microbial dysbiosis in T2DM pathogenesis. However, studies comparing the microbiome characteristics between T2DM and healthy controls have reported inconsistent results. To further identify and describe the characteristics of the intestinal flora of T2DM patients, we performed a systematic review and meta-analysis of stool microbial profiles to discern and describe microbial dysbiosis in T2DM and to explore heterogeneity among 7 studies (600 T2DM cases, 543 controls, 1143 samples in total). Using a random effects model and a fixed effects model, we observed significant differences in beta diversity, but not alpha diversity, between individuals with T2DM and controls. We identified various operational taxonomic unit (OTUs) and bacterial genera with significant odds ratios for T2DM. The T2DM signatures derived from a single study by stepwise feature selection could be applied in other studies. By training on multiple studies, we improved the detection accuracy and disease specificity for T2DM. We also discuss the relationship between T2DM-enriched or T2DM-depleted genera and probiotics and provide new ideas for diabetes prevention and improvement.


Subject(s)
Diabetes Mellitus, Type 2/complications , Dysbiosis/etiology , Gastrointestinal Microbiome , Case-Control Studies , Diabetes Mellitus, Type 2/metabolism , Feces/microbiology , Humans , Metagenome , Metagenomics/methods , Probiotics , RNA, Ribosomal, 16S , ROC Curve
12.
NPJ Biofilms Microbiomes ; 7(1): 60, 2021 07 15.
Article in English | MEDLINE | ID: mdl-34267209

ABSTRACT

Polycystic ovary syndrome (PCOS) is a common endocrine disease in females that is characterized by hyperandrogenemia, chronic anovulation, and polycystic ovaries. However, the exact etiology and pathogenesis of PCOS are still unknown. The aim of this study was to clarify the bacterial, stress status, and metabolic differences in the gut microbiomes of healthy individuals and patients with high body mass index (BMI) PCOS (PCOS-HB) and normal BMI PCOS (PCOS-LB), respectively. Here, we compared the gut microbiota characteristics of PCOS-HB, PCOS-LB, and healthy controls by 16S rRNA gene sequencing, FK506-binding protein 5 (FKBP5) DNA methylation and plasma metabolite determination. Clinical parameter comparisons indicated that PCOS patients had higher concentrations of total testosterone, androstenedione, dehydroepiandrosterone sulfate, luteinizing hormone, and HOMA-IR while lower FKBP5 DNA methylation. Significant differences in bacterial diversity and community were observed between the PCOS and healthy groups but not between the PCOS-HB and PCOS-LB groups. Bacterial species number was negatively correlated with insulin concentrations (both under fasting status and 120 min after glucose load) and HOMA-IR but positively related to FKBP5 DNA methylation. Compared to the healthy group, both PCOS groups had significant changes in bacterial genera, including Prevotella_9, Dorea, Maihella, and Slackia, and plasma metabolites, including estrone sulfate, lysophosphatidyl choline 18:2, and phosphatidylcholine (22:6e/19:1). The correlation network revealed the complicated interaction of the clinical index, bacterial genus, stress indices, and metabolites. Our work links the stress responses and gut microbiota characteristics of PCOS disease, which might afford perspectives to understand the progression of PCOS.


Subject(s)
DNA Methylation , Dysbiosis , Gastrointestinal Microbiome , Polycystic Ovary Syndrome/etiology , Polycystic Ovary Syndrome/metabolism , Stress, Physiological , Tacrolimus Binding Proteins/genetics , Adult , Biodiversity , Biomarkers , Case-Control Studies , Computational Biology , Disease Susceptibility , Female , Humans , Metabolome , Metabolomics/methods , Middle Aged , Obesity , Polycystic Ovary Syndrome/diagnosis , Young Adult
13.
J Gastroenterol Hepatol ; 36(4): 832-840, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33880762

ABSTRACT

For a long time, gut bacteria have been recognized for their important roles in the occurrence and progression of gastrointestinal diseases like colorectal cancer, and the ever-increasing amounts of microbiome data combined with other high-quality clinical and imaging datasets are leading the study of gastrointestinal diseases into an era of biomedical big data. The "omics" technologies used for microbiome analysis continuously evolve, and the machine learning or artificial intelligence technologies are key to extract the relevant information from microbiome data. This review intends to provide a focused summary of recent research and applications of microbiome big data and to discuss the use of artificial intelligence to combat gastrointestinal diseases.


Subject(s)
Artificial Intelligence/trends , Big Data , Gastrointestinal Diseases/etiology , Gastrointestinal Diseases/microbiology , Gastrointestinal Microbiome , Information Storage and Retrieval/methods , Datasets as Topic
14.
Microb Cell Fact ; 19(1): 192, 2020 Oct 08.
Article in English | MEDLINE | ID: mdl-33032584

ABSTRACT

An amendment to this paper has been published and can be accessed via the original article.

15.
Microb Cell Fact ; 19(1): 171, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32873292

ABSTRACT

BACKGROUND: Although recent studies have indicated that intestinal microbiota dweller are involved in the pathogenesis of allergy rhinitis (AR), the influence of gut microbiota on AR adult has not been fully elucidated yet. Hence, we carried out this study to uncover the distinctive bacterial taxa that differentiate allergy rhinitis patients from healthy individuals. Feces samples from thirty three AR patients and thirty one healthy individuals were analyzed by 16S rRNA gene sequencing. RESULTS: Results showed that the bacterial diversity in AR group was significantly higher than that of the non-AR group. Bacterial communities between AR and non-AR group were significantly differentiated as revealed by Principal coordinates analysis (PCoA) and the variation within non-AR were higher than that of the counterpart. Firmicutes, Fusobacteria, Actinobacteria, Cyanobacteria and Chloroflexi were the significantly differed phyla taxa and the top significantly distinguished bacterial genus included Prevotella_9, Phascolarctobacterium, Roseburia, Megamonas, Alistipes, Lachnoclostridium and Fusobacterium. The higher network complexity in AR group were dominated by taxa belonging to Firmicutes. The predicted function, alpha linolenic acid metabolism and bacterial invasion of epithelial cells pathway were higher in non-AR group while gonadotropin-releasing hormone (GnRH) signaling pathway, Fc γ-R mediated phagocytosis and endocytosis were higher in AR patients. Although the bacterial diversity between moderate and severe AR patients showed no significant difference, the significant correlation between featured genus and total nasal symptom score or rhinoconjunctivitis quality of life questionnaire, such as Butyricicoccus and Eisenbergiella, revealed the potential to intervene the AR status by means of gut microbiota. CONCLUSIONS: In conclusion, patients with allergy rhinitis had distinguished gut microbiota characteritics in comparison with healthy controls. The results suggest that gut microbiota might play crucial roles in influencing the course and different symptoms of AR. Trial registration ChiCTR, ChiCTR1900028613. Registered 29 December 2019, https://www.chictr.org.cn/showproj.aspx?proj=47650 .


Subject(s)
Biodiversity , Feces/microbiology , Gastrointestinal Microbiome , Rhinitis, Allergic/microbiology , Adult , China/epidemiology , Female , Genome, Bacterial , Humans , Male , Metagenome , Quality of Life , RNA, Ribosomal, 16S , Severity of Illness Index , Surveys and Questionnaires , Young Adult
16.
Sci Total Environ ; 741: 140423, 2020 Nov 01.
Article in English | MEDLINE | ID: mdl-32615432

ABSTRACT

With the increasing researches on the role of gut microbiota in human health and disease, appropriate storage method of fecal samples at ambient temperature would conveniently guarantee the precise and reliable microbiota results. Nevertheless, less choice of stabilizer that is cost-efficient and feasible to be used in longer preservation period obstructed the large-scale metagenomics studies. Here, we evaluated the efficacy of a guanidine isothiocyanate-based reagent method EffcGut and compared it with the other already used storage method by means of 16S rRNA gene sequencing technology. We found that guanidine isothiocyanate-based reagent method at ambient temperature was not inferior to OMNIgene·GUT OM-200 and it could retain the similar bacterial community as that of -80 °C within 24 weeks. Furthermore, bacterial diversity and community structure difference were compared among different sample fraction (supernatant, suspension and precipitate) preserved in EffcGut and -80 °C. We found that supernatant under the preservation of EffcGut retained the similar community structure and composition as that of the low temperature preservation method.


Subject(s)
Microbiota , Specimen Handling , Cost-Benefit Analysis , Feces , Humans , RNA, Ribosomal, 16S , Temperature
17.
Aging (Albany NY) ; 12(9): 8583-8604, 2020 05 11.
Article in English | MEDLINE | ID: mdl-32392181

ABSTRACT

Reduced bone mineral density (BMD) is associated with an altered microbiota in senile osteoporosis. However, the relationship among gut microbiota, BMD and bone metabolic indexes remains unknown in postmenopausal osteoporosis. In this study, fecal microbiota profiles for 106 postmenopausal individuals with osteopenia (n=33) or osteoporosis (n=42) or with normal BMD (n=31) were determined. An integrated 16S rRNA gene sequencing and LC-MS-based metabolomics approach was applied to explore the association of estrogen-reduced osteoporosis with the gut microbiota and fecal metabolic phenotype. Adjustments were made using several statistical models for potential confounding variables identified from the literature. The results demonstrated decreased bacterial richness and diversity in postmenopausal osteoporosis. Additionally, showed significant differences in abundance levels among phyla and genera in the gut microbial community were found. Moreover, postmenopausal osteopenia-enriched N-acetylmannosamine correlated negatively with BMD, and distinguishing metabolites were closely associated with gut bacterial variation. Both serum procollagen type I N propeptide (P1NP) and C-terminal telopeptide of type I collagen (CTX-1) correlated positively with osteopenia-enriched Allisonella, Klebsiella and Megasphaera. However, we did not find a significant correlation between bacterial diversity and estrogen. These observations will lead to a better understanding of the relationship between bone homeostasis and the microbiota in postmenopausal osteoporosis.


Subject(s)
Bone Density , Bone and Bones/physiology , Gastrointestinal Microbiome , Osteoporosis, Postmenopausal/metabolism , Absorptiometry, Photon , Bone Remodeling , Collagen Type I/metabolism , Feces/microbiology , Female , Humans , Mass Spectrometry , Metabolomics , Middle Aged , Osteoporosis, Postmenopausal/diagnosis , Osteoporosis, Postmenopausal/microbiology , RNA, Ribosomal, 16S/genetics
18.
Front Microbiol ; 11: 383, 2020.
Article in English | MEDLINE | ID: mdl-32265857

ABSTRACT

Dysbiosis of gut microbiota during the progression of HBV-related liver disease is not well understood, as there are very few reports that discuss the featured bacterial taxa in different stages. The aim of this study was to reveal the featured bacterial species whose abundances are directly associated with HBV disease progression, that is, progression from healthy subjects to, chronic HBV infection, chronic hepatitis B to liver cirrhosis. Approximately 400 fecal samples were collected, and 97 samples were subjected to 16S rRNA gene sequencing after age and BMI matching. Compared with the healthy individuals, significant gut microbiota alterations were associated with the progression of liver disease. LEfSe results showed that the HBV infected patients had higher Fusobacteria, Veillonella, and Haemophilus abundance while the healthy individuals had higher levels of Prevotella and Phascolarctobacterium. Indicator analysis revealed that 57 OTUs changed as the disease progressed, and their combination produced an AUC value of 90% (95% CI: 86-94%) between the LC and non-LC groups. In addition, the abundances of OTU51 (Dialister succinatiphilus) and OTU50 (Alistipes onderdonkii) decreased as the disease progressed, and these results were further verified by qPCR. The LC patients had the higher bacterial network complexity, which was accompanied with a lower abundance of potential beneficial bacterial taxa, such as Dialister and Alistipes, while they had a higher abundance of pathogenic species within Actinobacteria. The compositional and network changes in the gut microbiota in varied CHB stages, suggest the potential contributions of gut microbiota in CHB disease progression.

19.
Front Genet ; 10: 447, 2019.
Article in English | MEDLINE | ID: mdl-31191599

ABSTRACT

Colorectal cancer (CRC) ranks second in cancer-associated mortality and third in the incidence worldwide. Most of CRC follow adenoma-carcinoma sequence, and have more than 90% chance of survival if diagnosed at early stage. But the recommended screening by colonoscopy is invasive, expensive, and poorly adhered to. Recently, several studies reported that the fecal bacteria might provide non-invasive biomarkers for CRC and precancerous tumors. Therefore, we collected and uniformly re-analyzed these published fecal 16S rDNA sequencing datasets to verify the association and identify biomarkers to classify and predict colorectal tumors by random forest method. A total of 1674 samples (330 CRC, 357 advanced adenoma, 141 adenoma, and 846 control) from 7 studies were analyzed in this study. By random effects model and fixed effects model, we observed significant differences in alpha-diversity and beta-diversity between individuals with CRC and the normal colon, but not between adenoma and the normal. We identified various bacterial genera with significant odds ratios for colorectal tumors at different stages. Through building random forest model with 10-fold cross-validation as well as new test datasets, we classified individuals with CRC, advanced adenoma, adenoma and normal colon. All approaches obtained comparable performance at entire OTU level, entire genus level, and the common genus level as measured using AUC. When combined all samples, the AUC of random forest model based on 12 common genera reached 0.846 for CRC, although the predication performed poorly for advance adenoma and adenoma.

20.
Appl Environ Microbiol ; 84(19)2018 10 01.
Article in English | MEDLINE | ID: mdl-30054369

ABSTRACT

Prorocentrum donghaiense blooms occur frequently in the Yangtze River estuary and the adjacent East China Sea. These blooms have damaged marine ecosystems and caused enormous economic losses over the past 2 decades. Thus, highly efficient, low-cost, ecofriendly approaches must be developed to control P. donghaiense blooms. In this study, a bacterial strain (strain Y42) was identified as Paracoccus sp. and was used to lyse P. donghaiense The supernatant of the strain Y42 culture was able to lyse P. donghaiense, and the algicidal activity of this Y42 supernatant was stable with different temperatures and durations of light exposure and over a wide pH range. In addition to P. donghaiense, Y42 showed high algicidal activity against Alexandrium minutum, Scrippsiella trochoidea, and Skeletonema costatum, suggesting that it targets primarily Pyrrophyta. To clarify the algicidal effects of Y42, we assessed algal lysis and determined the chlorophyll a contents, photosynthetic activity, and malondialdehyde contents of P. donghaiense after exposure to the Y42 supernatant. Scanning electron microscopy and transmission electron microscopy analyses showed that the Y42 supernatant disrupted membrane integrity and caused algal cell breakage at the megacytic zone. Photosynthetic pigment loss and significant declines in both photosynthetic efficiency and the electron transport rate indicated that the Y42 supernatant damaged the photosynthetic system of P. donghaiense Malondialdehyde overproduction indicated that the Y42 supernatant caused lipid peroxidation and oxidative damage to membrane systems in the algal cell, ultimately leading to death. The findings of this study reveal the potential of Y42 to remove algal cells from P. donghaiense blooms.IMPORTANCEP. donghaiense is one of the most common dinoflagellate species that form harmful algal blooms, which frequently cause serious ecological pollution and pose health hazards to humans and other animals. Screening for bacteria with high algicidal activity against P. donghaiense and studying their algicidal processes and characteristics will contribute to an understanding of their algicidal effects and provide a theoretical basis for preventing algal blooms and reducing their harm to the environment. This study reports the algicidal activity and characteristics of Paracoccus against P. donghaiense The stability of the algicidal activity of Paracoccus in different environments (including different temperature, pH, and sunlight conditions) indicates its potential for use in the control of P. donghaiense blooms.


Subject(s)
Antibiosis , Dinoflagellida/microbiology , Paracoccus/physiology , Seawater/microbiology , China , Chlorophyll A/metabolism , Dinoflagellida/growth & development , Harmful Algal Bloom , Paracoccus/genetics , Paracoccus/isolation & purification , Photosynthesis
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