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Shoaie, S.

Publications and source records attributed to Shoaie, S..

16 recordsLinked to original sources

Metacontam: A Negative Control-Free Decontamination Method for Metagenomic Analysis

Shotgun metagenomic sequencing enables high-resolution profiling of host-associated microbial communities. However, contaminant DNA can substantially distort biological interpretations, especially in low-biomass samples. Here, we introduce Metacontam, a control-free method for species-level decontamination of shotgun metagenomic data. Metacontam integrates blacklist-guided community detection within a species correlation network with average nucleotide identity (ANI) to identify contaminants arising from shared sources. Across diverse low-biomass and mixed-biomass datasets, Metacontam outperformed existing approaches, improving the detection of low-abundance and low-prevalence contaminants while retaining biologically plausible taxa. It also reduces kit-specific biases in skin metagenomes and improves downstream analyses of tissue microbiome data. Together, these results demonstrate that Metacontam enables accurate identification of contaminant taxa across diverse metagenomic datasets, even in the absence of negative controls.

bioinformatics↗

Microbial oral-gut translocation in advanced chronic liver disease is linked to exacerbation of intestinal barrier dysfunction and hepatic fibrosis

While microbiome perturbations are associated with advanced chronic liver disease (ACLD), microbial disease mechanisms are poorly understood. Using multi-omics analyses of paired saliva and faecal samples from an ACLD cohort, we identified next-to-identical oral and gut bacterial strains (including Veillonella and Streptococcus spp.) which increased in absolute abundance in the gut of ACLD patients. These translocators uniquely encoded a collagenase-like proteinase (prtC) with the potential for gut barrier disruption and prtC faecal abundance was a robust ACLD biomarker (auPR=0.91). CCl4-treated mice inoculated with Veillonella and Streptococcus prtC-encoding patient isolates showed exacerbation of gut barrier impairment and hepatic fibrosis. Furthermore, faecal collagenase activity was increased in ACLD patients and experimentally confirmed for the prtC gene from translocating Veillonella parvula. Overall, our study establishes mechanistic links between oral-gut translocation and ACLD pathobiology, and identifies the oral microbiome as an important contributing factor with potential for microbial diagnostics and therapeutics.

microbiology↗

Enhanced Computational and Experimental Approaches for Comparative Analysis of the Human Mycobiome

The mycobiome is now recognized as a critical part of the human microbial ecosystem, playing a significant role in both health and disease. Mycobiome research is currently in its infancy and relies on fungal-specific primers with challenges in bioinformatics to accurately determine the structure of the mycobiota community. In addition, the majority of computational and experimental methods currently in use have been optimized for bacteria rather than for fungi. Here, we provide a comparative analysis of extraction methodologies for metagenome sequencing and subsequent bioinformatic analysis that will enhance fungal species identification. We utilized cultured mock fungal communities, including both yeast and mold species, to evaluate the efficiency of extraction protocols. We further enhanced computational analysis of the mycobiome, using mock and human metagenome data together with our curated catalogue consisting of 984 fungal genomes specific to the human mycobiome. Application of this optimised workflow for oral and gut samples of healthy individuals detected of novel species from Puccinia and Lentinus genera among the established presence of Malassezia, Rhizophagus, Candida and Saccharomyces genera. In addition, Enterocytozoon, was identified specifically in the gut mycobiome. Our pipeline enabled the comprehensive sampling of all fungal genes in a microbial community within a human sample minimising bias, reducing errors and artefacts from amplification, and providing accurate diversity and abundance data for the human mycobiome.

genomics↗

Microbiome signatures of virulence in the oral-gut-brain axis influence Parkinson's disease and cognitive decline pathophysiology

The human microbiome is increasingly recognized for its crucial role in the development and progression of neurodegenerative diseases. While the gut-brain axis has been extensively studied, the contribution of the oral microbiome and gut-oral tropism in neurodegeneration has been largely overlooked. Cognitive impairment (CI) is common in neurodegenerative diseases and develops on a spectrum. In Parkinsons Disease (PD) patients, CI is one of the most common non-motor symptoms but its mechanistic development across the spectrum remains unclear, complicating early diagnosis of at-risk individuals. Here, we generated 228 shotgun metagenomics samples of the gut and oral microbiomes across PD patients with either mild cognitive impairment (PD-MCI) or dementia (PDD), and a healthy cohort, to study the role of the gut and oral microbiomes on CI in PD. In addition to revealing compositional and functional signatures, the role of pathobionts, and dysregulated metabolic pathways of the oral and gut microbiome in PD-MCI and PDD, we also revealed the importance of oral-gut translocation in increasing abundance of virulence factors in PD and CI. The oral-gut virulence was further integrated with saliva metaproteomics and demonstrated their potential role in dysfunction of host immunity and brain endothelial cells. Our findings highlight the significance of the oral-gut-brain axis and underscore its potential for discovering novel biomarkers for PD and CI.

microbiology↗

Extensively acquired antimicrobial resistant bacteria restructure the individual microbial community in post-antibiotic conditions

In recent years, the overuse of antibiotics has led to the emergence of antimicrobial resistant (AMR) bacteria. To evaluate the spread of AMR bacteria, the reservoir of AMR genes (resistome) has traditionally been identified from environmental samples, hospital environments, and human populations; however, the functional role of AMR bacteria in the human gut microbiome and their persistency within individuals has not been fully investigated. Here, we performed a strain-resolved in-depth analysis of the resistome changes by reconstructing a large number of metagenome-assembled genomes (MAGs) of antibiotics- treated individuals gut microbiome. Interestingly, we identified two bacterial populations with different resistome profiles, extensively acquired antimicrobial resistant bacteria (EARB) and sporadically acquired antimicrobial resistant bacteria (SARB), and found that EARB showed broader drug resistance and a significant functional role in shaping individual microbiome composition after antibiotic treatment. Furthermore, longitudinal strain analysis revealed that EARB bacteria were inherently carried by individuals and can reemerge through strain switching in the human gut microbiome. Our data on the presence of AMR bacteria in the human gut microbiome provides a new avenue for controlling the spread of AMR bacteria in the human community.

genomics↗

MIGRENE: The toolbox for microbial and individualized GEMs, reactobiome and community network modelling

MotivationUnderstanding microbial metabolism is crucial for evaluating shifts in human host-microbiome interactions during health and disease. However, the primary hurdle in the realm of constraint-based modeling and genome-scale metabolic models (GEMs) pertaining to host-microbiome interactions lies in the efficient utilization of metagenomic data for constructing GEMs that encompass unexplored and uncharacterized genomes. Challenges persist in effectively employing metagenomic data to address individualized microbial metabolism to investigate host-microbiome interactions. ResultTo tackle this issue, we have created a computational framework designed for personalized microbiome metabolism. This framework takes into account factors such as microbiome composition, metagenomic species profiles and microbial gene catalogues. Subsequently, it generates GEMs at microbial level and individualized microbiome metabolism, including reaction richness, reaction abundance, reactobiome, individualized reaction set enrichment (iRSE), and community models. Availability and implementationThe MIGRENE toolbox is freely available at our GitHub repository https://github.com/sysbiomelab/MIGRENE. Comprehensive tutorials on the GitHub were provided for each step of the workflow.

systems biology↗

Impact of Yaq-001, a non-absorbable, engineered carbon bead of controlled porosity in rodent models of cirrhosis and acute on chronic liver failure

ObjectiveTranslocation of gut bacterial lipopolysaccharide (LPS) is associated with complications of cirrhosis. Current strategies to target bacterial translocation are limited to antibiotics with risk of resistance. This study aims to explore therapeutic potential of a non-absorbable, engineered carbon bead, Yaq-001 in cirrhosis and acute-on-chronic liver failure (ACLF) models. DesignThe performance of Yaq-001 was evaluated in in vitro studies. Two-rodent models of cirrhosis (4-week, bile duct ligation (BDL): Sham (n=36); Sham-Yaq-001 (n=30); BDL (n=37); BDL-Yaq-001 (n=44)) and ACLF (BDL-LPS: Sham-LPS (n=9); Sham-LPS-Yaq-001 (n=10); BDL-LPS (n=16); BDL-LPS-Yaq-001(n=12)). The treated-groups received Yaq-001 for 2-weeks. Samples were collected for assessment of organ and immune function, transcriptomics, microbiome composition and metabolomics. ResultsIn vitro, Yaq-001 exhibited rapid adsorption kinetics for endotoxin and bile acids without exerting an antibiotic effect. In vivo, Yaq-001 produced significant improvement in ALT, ammonia, liver cell death, portal pressure, markers of systemic inflammation and renal function in BDL animals. Yaq-001-treated ACLF animals had significantly better survival, ALT, portal pressure, brain water and creatinine. Ex-vivo LPS-induced reactive oxygen species production in portal venous monocytes and Kupffer cell populations was diminished with Yaq-001 treatment. Transcriptome analysis demonstrated a significant modulation of inflammation, cell death and senescence pathways in the liver, kidneys, brain and colon of Yaq-001-treated BDL rats. Yaq-001 impacted positively on the microbiome composition with significant modulation of Family Porphyromonadaceae and Genus Barnesiella. Urinary 1HNMR analysis suggested a shift in metabolomic signature in Yaq-001-treated BDL rats. ConclusionsThis study provides strong pre-clinical rationale for developing Yaq-001 for treatment of patients with cirrhosis. Significance of this studyO_ST_ABSWhat is already known on this topic?C_ST_ABSCurrent strategies to target bacterial translocation in cirrhosis are limited to antibiotics with risk of resistance. Yaq-001 is an insoluble, non-absorbable, non-antibiotic, engineered carbon bead of tailored porosities, which works as an adsorbent in the gut and is completely excreted after oral administration. What this study adds?O_LIYaq-001 rapidly adsorbs endotoxin, ammonia and bile acids without influencing bacterial growth kinetics in vitro. C_LIO_LIYaq-001 reduces mortality of ACLF animals and impacts positively on markers of gut permeability, liver injury, portal pressure, brain and kidneys in rodent models of cirrhosis and ACLF. C_LIO_LIYaq-001 administration was associated with positive impact on the composition of the gut microbiota, reduction in severity of endotoxemia and ammonia, which significantly reduced the severity of inflammation, cell death, signaling pathways and LPS sensitivity. C_LI How this study might affect research, practice or policy?The data provide the pre-clinical rationale to proceed to clinical trials in patients with cirrhosis aiming to prevent the occurrence of complications.

animal behavior and cognition↗

Pathogenic entero- and salivatypes harbour changes in microbiome virulence and antimicrobial resistance genes with increasing chronic liver disease severity

Background & AimsLife-threatening complications of cirrhosis are triggered by bacterial infections, with the ever-increasing threat of antimicrobial resistance (AMR). Alterations in the gut microbiome in decompensated cirrhosis (DC) and acute-on-chronic liver failure (ACLF) are recognised to influence clinical outcomes, whilst the role of the oral microbiome is still being explored. Our aims were to simultaneously interrogate the gut and oral micro- and mycobiome in cirrhotic patients, and assess microbial community structure overlap in relation to clinical outcomes, as well as alterations in virulence factors and AMR genes. Methods18 healthy controls (HC), 20 stable cirrhotics (SC), 50 DC, 18 ACLF and 15 with non-liver sepsis (NLS) i.e. severe infection but without cirrhosis, were recruited at a tertiary liver centre. Shotgun metagenomic sequencing was undertaken from saliva (S) and faecal (F) samples (paired where possible). Salivatypes and enterotypes based on clustering of genera were calculated and compared in relation to cirrhosis severity and in relation to specific clinical parameters. Virulence and antimicrobial resistance genes (ARGs) were evaluated in both oral and gut niches, and distinct resistotypes identified. ResultsSpecific saliva- and enterotypes revealed a greater proportion of pathobionts with concomitant reduction in autochthonous genera with increasing cirrhosis severity, and in those with hyperammonemia. Overlap between oral and gut microbiome communities was observed and was significantly higher in DC and ACLF vs SC and HCs, independent of antimicrobial, beta-blocker and acid suppressant use. Two distinct gut microbiome clusters [ENT2/ENT3] harboured genes encoding for the phosphoenolpyruvate:sugar phosphotransferase system (PTS) system and other virulence factors in patients with DC and ACLF. Substantial numbers of ARGs (oral: 1,218 and gut: 672) were detected with 575 ARGs common to both sites. The cirrhosis resistome was significantly different to HCs, with three and four resistotypes identified for the oral and gut microbiome, respectively. DiscussionOral and gut microbiome profiles differ significantly with increasing severity of cirrhosis, with progressive dominance of pathobionts and loss of commensals. DC and ACLF have significantly worse microbial diversity than NLS, despite similar antimicrobial exposure, supporting the additive patho-biological effect of cirrhosis. The degree of microbial community overlap between sites, frequency of virulence factors and presence of ARGs, all increment significantly with hepatic decompensation. These alterations may predispose to higher infection risk, poorer response to antimicrobial therapy and worsening outcomes, and provide the rationale for developing non-antibiotic-dependent microbiome-modulating therapies.

physiology↗

PaliDIS: A tool for fast discovery of novel insertion sequences

The diversity of microbial insertion sequences, crucial mobile genetic elements in generating diversity in microbial genomes, needs to be better represented in current microbial databases. Identification of these sequences in microbiome communities presents some significant problems that have led to their underrepresentation. Here, we present a bioinformatics pipeline called Palidis that recognises insertion sequences in metagenomic sequence data rapidly by identifying inverted terminal repeat regions from mixed microbial community genomes. Applying Palidis to 264 human metagenomes identifies 879 unique insertion sequences, with 519 being novel and not previously characterised. Querying this catalogue against a large database of isolate genomes reveals evidence of horizontal gene transfer events across bacterial classes. We will continue to apply this tool more widely, building the Insertion Sequence Catalogue, a valuable resource for researchers wishing to query their microbial genomes for insertion sequences. Data SummaryO_LIPalidis is available here: github.com/blue-moon22/palidis C_LIO_LIThe Insertion Sequence Catalogue is available to download here: https://github.com/blue-moon22/ISC C_LIO_LIThe raw reads from the Human Microbiome Project can be retrieved using the download links provided in Supplementary Data 1 C_LIO_LIThe analysis for this paper is available here: github.com/blue-moon22/palidis_paper_analysis C_LIO_LIThe output of Palidis that was run on these reads is available in Supplementary Data 2 C_LI Impact StatementInsertion sequences are a class of transposable element that play an important role in the dissemination of antimicrobial resistance genes. However, it is challenging to completely characterise the transmission dynamics of insertion sequences and their precise contribution to the spread of antimicrobial resistance. The main reasons for this are that it is impossible to identify all insertion sequences based on limited reference databases and that de novo computational methods are ill-equipped to make fast or accurate predictions based on incomplete genomic assemblies. Palidis generates a larger, more comprehensive catalogue of insertion sequences based on a fast algorithm harnessing genomic diversity in mixed microbial communities. This catalogue will enable genomic epidemiologists and researchers to annotate genomes for insertion sequences more extensively and advance knowledge of how insertion sequences contribute to bacterial evolution in general and antimicrobial resistance spread across microbial lineages in particular. This will be useful for genomic surveillance, and for development of microbiome engineering strategies targeting inactivation or removal of important transposable elements carrying antimicrobial resistance genes.

genomics↗

Metabolic modelling of the human gut microbiome in type 2 diabetes patients in response to metformin treatment

The human gut microbiome has been associated with several metabolic disorders including type 2 diabetes. Understanding metabolic changes in the gut microbiome is important to elucidate the role of gut bacteria in regulating host metabolism. Here, we used available metagenomics data from a metformin study, together with genome-scale metabolic modelling of the key bacteria in individual and community-level to investigate the mechanistic role of the gut microbiome in response to metformin. Individual modelling predicted that species that are increased after metformin treatment have higher growth rates in comparison to species that are decreased after metformin treatment. Gut microbial enrichment analysis showed prior to metformin treatment pathways related to the hypoglycemic effect were enriched. Our observations highlight how the key bacterial species after metformin treatment have commensal and competing behavior, and how their cellular metabolism changes due to different nutritional environment. Integrating different diets showed there were specific microbial alterations between different diets. These results show the importance of the nutritional environment and how the dietary guidelines may improve drug efficiency through the gut microbiota.

systems biology↗

GutMicroNet: an interactive platform for gut microbiome interaction exploration

The human gut microbiome data has been proven to be a powerful tool to understand the human body in both health and disease conditions. However, understanding their complex interactions and impact on the human body remains a challenging task. Unravelling the species-level interactions could allow us to study the causality of the microbiome. Moreover, it could lead us to better understand the underlying mechanisms of complex diseases and, subsequently, the discovery of new therapeutic targets. Given these challenges and benefits, it has become evident that a freely accessible and centralized platform for presenting gut microbiome interaction is essential to untangle the complexity and open multiple new paths and opportunities in disease- and drug-related research. Here, we present GutMicroNet, an interactive visualization platform of human gut microbiome interaction networks. We generated 45 gut microbiome co-abundance networks from various geographical origins, gender, and diseases based on the data presented in the Human Gut Microbiome Atlas. This interactive platform includes more than 1900 gut microbiome species and allows users to query multiple species at the same time based on their interests and adjust it based on the statistical properties. Moreover, users can download publication-ready figures or network information for further analysis. The platform can be accessed freely on https://gutmicro.net without any login requirements or limitations, including access to the full networks data.

systems biology↗

Integrative functional analysis uncovers metabolic differences between Candida species

Candida species are a dominant constituent of the human mycobiome and a better understanding of their metabolism from a fungal perspective can provide key insights into their ability to cause pathogenesis. Here, we have developed the BioFung database - a fungal specific tool for functional annotation using the KEGG database that provides an efficient method for annotation of protein-encoding gene. Analysis of carbohydrate-active enzyme (CAZymes) and BioFung, uncovered core and accessory features across Candida species demonstrating plasticity, adaptation to the environment and acquired features. Integerative functional analysis revealed that all Candida species can employ amino acid metabolism. However, metabolomics revealed that only a specific cluster of species (AGAu species - C. albicans, C. glabrata and C. auris) utilised amino acid metabolism. We identified critical metabolic pathways in the AGAu clusters with biomarkers and anti-fungal target potential in the CAZyme profile, polyamine, choline and fatty acid biosynthesis pathways. This study, combining genomic analysis, metabolomics and gene expression validation, highlights the metabolic diversity within AGAu species that underlies their remarkable ability to dominate the mycobiome and cause disease.

systems biology↗

Comparative genomics analysis of Chryseobacterium sp. KMC2 reveals metabolic pathways involved in keratinous utilization and natural product biosynthesis

Several efforts have been made to valorize keratinous materials, an abundant and renewable resource. Despite these attempts to valorize products generated from keratin hydrolysate, either via chemical or microbial conversion, they generally remain with an overall low value. In this study, a promising keratinolytic strain from the genus Chryseobacterium (Chryseobacterium sp. KMC2) was investigated using comparative genomic tools against publicly available reference genomes to reveal the metabolic potential for biosynthesis of valuable secondary metabolites. Genome and metabolic features of four species were compared, shows different gene numbers but similar functional categories. We successfully mined eleven different secondary metabolite gene clusters of interest from the four genomes, including five common ones shared across all genomes. Among the common metabolites, we identified gene clusters involved in biosynthesis of flexirubin-type pigment, microviridin, and siderophore, all showing remarkable conservation across the four genomes. Unique secondary metabolite gene clusters were also discovered, for example, ladderane from Chryseobacterium sp. KMC2. Additionally, this study provides a more comprehensive understanding of the potential metabolic pathways of keratin utilization in Chryseobacterium sp. KMC2, with the involvement of amino acid metabolism, TCA cycle, glycolysis/gluconeogenesis, propanoate metabolism, and sulfate reduction. This work uncovers the biosynthesis of secondary metabolite gene clusters from four keratinolytic Chryseobacterium spp. and shades lights on the keratinolytic potential of Chryseobacterium sp. KMC2 from a genome-mining perspective, providing alternatives to valorize keratinous materials into high-value natural products. ImportanceKeratin is an abundant and renewable resource from slaughterhouses or the poultry industry. Low-value products such as animal feed and fertilizer were generated from these feedstocks based on conventional processing like chemical conversion. In fact, microorganisms possess the potential to synthesize valuable natural products. In this work, we explored the metabolic potential of Chryseobacterium sp. KMC2, which was isolated with efficient keratinolytic capacity from a previous study. Comparative genomics analysis displayed similar functional categories against three publicly available reference genomes of keratin-degrading Chryseobacterium spp.. Eleven different secondary metabolite gene clusters of interest were mined among four genomes, including five common and unique ones. Furthermore, we provide a more comprehensive understanding of metabolic pathways on keratin utilization in Chryseobacterium sp. KMC2, with the involvement of amino acid assimilation and sulfate reduction. These findings contribute to expanding the application of Chryseobacterium sp. KMC2 on the valorization of keratinous materials.

microbiology↗

The Reactobiome Unravels a New Paradigm in Human Gut Microbiome Metabolism

Changes in microbial metabolism have been used as the main approach to assess function and elucidate environmental and host-microbiome interactions. This can be hampered by uncharacterised metagenome species and lack of metabolic annotation. To address this, we present a comprehensive computational platform for population stratification based on microbiome composition, the underlying metabolic potential and generation of metagenome species and community level metabolic models. We revisit the concepts of enterotype and microbiome richness introducing the reactobiome as a stratification method to unravel the metabolic features of the human gut microbiome. The reactobiome encapsulates resilience and microbiome dysbiosis at a functional level. We describe five reactotypes in healthy populations from 16 countries, with specific amino acid, carbohydrate and xenobiotic metabolic features. The validity of the approach was tested to unravel host-microbiome and environmental interactions by applying the reactobiome analysis on a one-year Swedish longitudinal cohort, integrating gut metagenomics, plasma metabolomics and clinical data.

systems biology↗

Compositional and functional differences of the mucosal microbiota along the intestine of healthy individuals

Gut mucosal microbes evolved closest to the host, developing specialized local communities. There is, however, insufficient knowledge of these communities as most studies have employed sequencing technologies to investigate faecal microbiota. This work used shotgun metagenomics of mucosal biopsies to explore the microbial communities compositions of terminal ileum and large intestine in 5 healthy individuals. Functional annotations and genome-scale metabolic modelling of selected species were then employed to identify local functional enrichments. While faecal metagenomics provided a good approximation of the average gut microbiome composition, mucosal biopsies allowed detecting the subtle variations of local microbial communities. Given their significant enrichment in the mucosal microbiota, we highlight the roles of Bacteroides species and describe the antimicrobial resistance biogeography along the intestine. We also detail which species, at which locations, are involved with the tryptophan/indole pathway, whose malfunctioning has been linked to pathologies including inflammatory bowel disease. Our study thus provides invaluable resources for investigating mechanisms connecting gut microbiota and host pathophysiology.

systems biology↗

Abundance and diversity of resistomes differ between healthy human oral cavities and gut

The global threat of the \"antimicrobial resistance apocalypse\" that has arisen in recent years has driven the use of high-throughput sequencing techniques to monitor the profile of resistance genes, known as the \"resistome\", in microbial populations. The human oral cavity contains a poorly explored reservoir of these genes, and little is known about their abundance and diversity, or how their profile compares with antimicrobial resistance genes in the gut. Here we analyse the resistome profiles of 788 oral cavities worldwide and compare these profiles with paired stool samples from shotgun metagenomic data. We find country and body site-specific differences in the prevalence of antimicrobial resistance genes, classes and mechanisms in oral and stool samples. However, the abundance of these antimicrobial resistance classes do not correlate with antibiotic prescription rates. A greater similarity was found in interpersonal resistomes between the same body sites than intrapersonal resistomes across different body sites. Between individuals, the oral cavity contains the highest and lowest abundances of specific antimicrobial resistance genes, but a lower diversity of resistance genes compared to the gut, which is likely influenced by differences in microbial composition and exposure to antimicrobial selection pressures. Co-occurrence analysis shows contrasting ARG-species associations between saliva and stool samples. This is the first study to date that characterises the oral cavity resistome worldwide, identifying its distinctive signatures compared to the gut.Maintenance and persistence of antimicrobial resistance is likely to vary across different body sites. Thus, we highlight the importance of characterising the resistome across body sites to uncover the antimicrobial resistance potential in the human body.

microbiology↗