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Adebayo, O.

Publications and source records attributed to Adebayo, O..

4 recordsLinked to original sources

Hydrocarbon-degrading microbial populations in permanently cold deep-sea sediments in the NW Atlantic

Permanently cold deep-sea sediments (2500-3500 m water depth) with or without indications of thermogenic hydrocarbon seepage were exposed to naphtha to examine the presence and potential of aerobic hydrocarbon-degrading microbial populations. Monitoring these microcosms for volatile hydrocarbons by GC-MS revealed sediments without in situ hydrocarbons responded more rapidly to naphtha amendment than hydrocarbon seep sediments overall, but seep sediments removed BTEX compounds more readily. Naphtha-driven aerobic respiration was more evident in surface sediment (0-20 cmbsf) than deeper anoxic layers (>130 cmbsf) that responded less rapidly. In all cases, enrichment of Gammaproteobacteria included lineages of Oleispira, Pseudomonas, and Alteromonas known to be associated with marine oil spills. On the other hand, taxa known to be prevalent in situ and diagnostic for thermogenic hydrocarbon seepage in deep sea sediment did not respond to naphtha amendment. This suggests a limited role for seep-associated populations in the context of oil spill biodegradation.

microbiology↗

Bacterial anomalies in seabed sediments associated with deep water hydrocarbon seepage

Deep sea hydrocarbon seep detection relies predominantly on geochemical analyses of seabed marine sediment cores to identify the presence of gas or oil. The presence of seeping hydrocarbons in these locations alters resident microbial community structure, leading to culture-based biodegradation assays as a complement to geochemical tools for seep detection. Biodiversity surveys of microbial communities can offer a similar proxy for seeping hydrocarbons, but this strategy has not been extensively investigated in deep water settings. In this study, 16S rRNA gene sequencing of bacterial communities was performed on sediment cores obtained in >2500 m water depth at 43 different locations in the NW Atlantic Ocean. Core samples from as deep as 10 metres below seafloor (mbsf) were assessed for gas composition, gas isotopes and liquid hydrocarbons. Over 650 bacterial 16S rRNA gene amplicon libraries were constructed from different sediment depths at these locations. Select sites showed strong evidence for the presence of thermogenic or biogenic hydrocarbons such that bacterial population analyses revealed significant differences between hydrocarbon seep and non-seep locations. Specific bacterial indicators were associated with different sediment depth intervals. Caldatribacteriota and Campilobacterota OTUs were observed in high relative sequence abundance in hydrocarbon seep sediments, particularly in the 20-50 cmbsf interval. Furthermore, these groups were differentially abundant between sites with thermogenic and biogenic hydrocarbons. The patterns revealed here suggest that microbial screening has the potential to play a key role in hydrocarbon seep detection and characterisation in remote deep-sea environments.

microbiology↗

Integrative genomic and epigenomic analyses identified IRAK1 as a novel target for chronic inflammation-driven prostate tumorigenesis

The impacts of many inflammatory genes in prostate tumorigenesis remain understudied despite the increasing evidence that associates chronic inflammation with prostate cancer (PCa) initiation, progression, and therapy resistance. The overarching goal of this study was to identify dysregulated inflammatory genes that correlate with PCa progression and decipher their molecular mechanisms as well as clinical significance in PCa using integrative genomics, transcriptomics, and epigenomics approach. Our Weighted Gene Co-expression Analysis (WGCNA) and multivariate analysis identified 10 inflammatory genes: IRAK1, PPIL5/LRR1, HMGB3, HMGB2, TRAIP, IL1F5/IL36RN, ILF2, TRIM59, NFKBIL2/TONSL, and TRAF7 that were significantly associated with PCa progression. We explored the potentials of IRAK1 and other inflammatory genes as diagnostic and/or prognostic biomarkers by performing both KM survival and AUROC curve analyses. Our results indicate the clinical significance of these inflammatory genes in predicting the development and progression of PCa. IRAK1 was found to be overexpressed and hypomethylated in most PCa samples. A significantly high percentage of castration-resistant PCa (CRPC) and neuroendocrine PCa (NEPC) samples display copy number variations, especially amplification of the IRAK1 gene compared to the indolent prostate adenocarcinoma (PRAD) samples. Furthermore, we identified missense and frameshift mutations of IRAK1 in a few PRAD samples with potential functional implications. In conclusion, the results from this study suggest that IRAK1 dysregulation may be an important contributor to chronic prostatitis (inflammation) and PCa progression.

cancer biology↗

Thermogenic hydrocarbons sustain diverse subseafloor microbial communities in deep sea cold seep sediments

At marine cold seeps, gaseous and liquid hydrocarbons migrate from deep subsurface origins to the sediment-water interface. Cold seep sediments are known to host taxonomically diverse microorganisms, but little is known about their metabolic potential and depth distribution in relation to hydrocarbon and electron acceptor availability. In this work, we combined geochemical, metagenomic and metabolomic measurements in distinct sediment redox regimes to profile microbial activities within the uppermost 350 cm of a newly discovered cold seep in the NW Atlantic deep sea (2.3 km water depth). Depth-resolved metagenomic profiling revealed compositional and functional differentiation between near-surface sediments (dominated by Proteobacteria) and deeper subsurface layers (dominated by Atribacteria, Chloroflexi, Euryarchaeota and Lokiarchaeota). Metabolic capabilities of community members were inferred from 376 metagenome-assembled genomes spanning 46 phyla (including five novel candidate phyla). In deeper sulfate-reducing and methanogenic sediments, various community members are capable of anaerobically oxidizing short-chain alkanes (alkyl-CoM reductase pathway), longer-chain alkanes (fumarate addition pathway), and aromatic hydrocarbons (fumarate addition and subsequent benzoyl-CoA pathways). Geochemical profiling demonstrated that hydrocarbon substrates are abundant in this location, thermogenic in origin, and subject to biodegradation. The detection of alkyl-/arylalkylsuccinate metabolites, together with carbon isotopic signatures of ethane, propane and carbon dioxide, support that microorganisms are actively degrading hydrocarbons in these sediments. Hydrocarbon oxidation pathways operate alongside other deep seabed metabolisms such as sulfide oxidation, hydrogen oxidation, carbon fixation, fermentation and reductive dehalogenation. Upward migrated thermogenic hydrocarbons thus sustain diverse microbial communities with activities that affect subseafloor biogeochemical processes across the redox spectrum in deep sea cold seeps.

microbiology↗