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1.
Plant J ; 117(2): 498-515, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37856574

RESUMO

Salt glands are the unique epidermal structures present in recretohalophytes, plants that actively excrete excess Na+ by salt secretory structures to avoid salt damage. Here, we describe a transmembrane protein that localizes to the plasma membrane of the recretohalophyte Limonium bicolor. As virus-induced gene silencing of the corresponding gene LbRSG in L. bicolor decreased the number of salt glands, we named the gene Reduced Salt Gland. We detected LbRSG transcripts in salt glands by in situ hybridization and transient transformation. Overexpression and silencing of LbRSG in L. bicolor pointed to a positive role in salt gland development and salt secretion by interacting with Lb3G16832. Heterologous LbRSG expression in Arabidopsis enhanced salt tolerance during germination and the seedling stage by alleviating NaCl-induced ion stress and osmotic stress after replacing or deleting the (highly) negatively charged region of extramembranous loop. After screened by immunoprecipitation-mass spectrometry and verified using yeast two-hybrid, PGK1 and BGLU18 were proposed to interact with LbRSG to strengthen salt tolerance. Therefore, we identified (highly) negatively charged regions in the extramembrane loop that may play an essential role in salt tolerance, offering hints about LbRSG function and its potential to confer salt resistance.


Assuntos
Plumbaginaceae , Tolerância ao Sal , Animais , Tolerância ao Sal/genética , Plumbaginaceae/genética , Plumbaginaceae/metabolismo , Glândula de Sal , Plântula/genética , Germinação , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas
2.
Int J Cardiol ; 395: 131400, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37769969

RESUMO

BACKGROUND: Heart failure (HF) is a disease closely associated with inflammation, and the systemic immune-inflammation index (SII) is a novel inflammatory marker. Therefore, this study aims to explore the relationship between SII and HF. METHODS: We used National Health and Nutrition Examination Survey data from 1998 to 2018 to include adults who reported a diagnosis of HF and complete information on the calculation of SII. SII was calculated as platelet count × neutrophil count/lymphocyte count. We used multiple logistic regression models to examine the association between SII and HF and explored possible influencing factors by subgroup analysis. In addition, we performed smoothed curve fitting and threshold effect analysis to describe the nonlinear relationship. RESULTS: The population-based study involved a total of 48,155 adults ages 20-85. Multivariate logistic regression showed that participants with the highest SII had a statistically significant 32% increased risk of HF prevalence compared to those with the lowest SII (OR = 1.32; 95% CI, 1.06-1.65, P = 0.0144) in a fully adjusted model. Subgroup analysis revealed no significant interactions between SII and specific subgroups (p > 0.05 for all interactions). Furthermore, the association between SII and HF was non-linear; the inflection point was 1104.78 (1000 cells/µl). CONCLUSIONS: Based on our findings, elevated SII levels were found to be strongly associated with the risk of HF, and SII was nonlinearly associated with HF. To validate these findings, a larger prospective investigation is needed to support the results of this study and investigate potential problems.


Assuntos
Insuficiência Cardíaca , Adulto , Humanos , Inquéritos Nutricionais , Estudos Prospectivos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Inflamação/diagnóstico , Inflamação/epidemiologia , Contagem de Leucócitos
3.
Environ Sci Pollut Res Int ; 30(52): 112943-112958, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37845597

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are widespread contaminants, but few studies have explored the relationship between PFAS and levels of metabolic syndrome (MetS) in the population. The available evidence of an association is also conflicting. We selected adults and adolescents with complete PFAS data from the National Health and Nutrition Examination Survey conducted between 2003 and 2018. We analyzed the association between PFAS and MetS using multivariate logistic regression models and evaluated potential nonlinear relationships with restricted cubic spline models. Additionally, we employed weighted quantile sum (WQS) regressions to uncover the multiple exposure effects and relative weights of each PFAS. Finally, we conducted a series of sensitivity analyses to test the robustness of our findings. In this population-based study, we analyzed data from a total of 4,973 adults, aged 20-85 years, and 1,381 adolescents, aged 12-19 years. Using fully adjusted multivariate logistic regression models, we found that serum levels of perfluorodecanoate (PFDA) [0.65 (0.50, 0.85)] and total PFAS [0.92 (0.85, 0.99)] were negatively associated with the prevalence of MetS in adults. Similarly, in adolescents, we observed negative correlations between the prevalence of MetS and levels of PFDA [0.55 (0.38, 0.80)], perfluorooctanoic acid (PFOA) [0.62 (0.39, 1.00)], perfluorooctane sulfonic acid (PFOS) [0.59 (0.36, 0.96)], and total PFAS [0.61 (0.37, 0.99)]. Additionally, our study identified statistically significant negative associations between serum levels of PFAS and certain components of MetS, primarily elevated fasting glucose and lower high-density lipoprotein cholesterol. Our study found that PFAS was associated with a lower prevalence of MetS in both adults and adolescents, offering new insights into the relationship between PFAS and metabolic health. Interestingly, however, we observed conflicting findings across the components of MetS. Specifically, we observed that PFAS had a negative correlation with some metrics and a positive correlation with others. These conflicting results point to a complex interplay between PFAS and various metrics of metabolic health.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Síndrome Metabólica , Adulto , Humanos , Adolescente , Síndrome Metabólica/epidemiologia , Inquéritos Nutricionais , HDL-Colesterol
4.
ISME J ; 17(11): 1907-1919, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37658181

RESUMO

Analyses of gene expression of subsurface bacteria and archaea provide insights into their physiological adaptations to in situ subsurface conditions. We examined patterns of expressed genes in hydrothermally heated subseafloor sediments with distinct geochemical and thermal regimes in Guaymas Basin, Gulf of California, Mexico. RNA recovery and cell counts declined with sediment depth, however, we obtained metatranscriptomes from eight sites at depths spanning between 0.8 and 101.9 m below seafloor. We describe the metabolic potential of sediment microorganisms, and discuss expressed genes involved in tRNA, mRNA, and rRNA modifications that enable physiological flexibility of bacteria and archaea in the hydrothermal subsurface. Microbial taxa in hydrothermally influenced settings like Guaymas Basin may particularly depend on these catalytic RNA functions since they modulate the activity of cells under elevated temperatures and steep geochemical gradients. Expressed genes for DNA repair, protein maintenance and circadian rhythm were also identified. The concerted interaction of many of these genes may be crucial for microorganisms to survive and to thrive in the Guaymas Basin subsurface biosphere.


Assuntos
Archaea , Sedimentos Geológicos , Sedimentos Geológicos/microbiologia , Filogenia , Bactérias , Expressão Gênica , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
5.
Nat Commun ; 14(1): 1513, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934105

RESUMO

Hepatocytes function largely through the secretion of proteins that regulate cell proliferation, metabolism, and intercellular communications. During the progression of hepatocellular carcinoma (HCC), the hepatocyte secretome changes dynamically as both a consequence and a causative factor in tumorigenesis, although the full scope of secreted protein function in this process remains unclear. Here, we show that the secreted pseudo serine protease PRSS35 functions as a tumor suppressor in HCC. Mechanistically, we demonstrate that active PRSS35 is processed via cleavage by proprotein convertases. Active PRSS35 then suppresses protein levels of CXCL2 through targeted cleavage of tandem lysine (KK) recognition motif. Consequently, CXCL2 degradation attenuates neutrophil recruitment to tumors and formation of neutrophil extracellular traps, ultimately suppressing HCC progression. These findings expand our understanding of the hepatocyte secretome's role in cancer development while providing a basis for the clinical translation of PRRS35 as a therapeutic target or diagnostic biomarker.


Assuntos
Carcinoma Hepatocelular , Armadilhas Extracelulares , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Armadilhas Extracelulares/metabolismo , Peptídeo Hidrolases/metabolismo , Hepatócitos/metabolismo , Linhagem Celular Tumoral , Quimiocina CXCL2/metabolismo
6.
Front Microbiol ; 14: 1078171, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846759

RESUMO

Sponges are widely distributed in the global ocean and harbor diverse symbiotic microbes with mutualistic relationships. However, sponge symbionts in the deep sea remain poorly studied at the genome level. Here, we report a new glass sponge species of the genus Bathydorus and provide a genome-centric view of its microbiome. We obtained 14 high-quality prokaryotic metagenome-assembled genomes (MAGs) affiliated with the phyla Nitrososphaerota, Pseudomonadota, Nitrospirota, Bdellovibrionota, SAR324, Bacteroidota, and Patescibacteria. In total, 13 of these MAGs probably represent new species, suggesting the high novelty of the deep-sea glass sponge microbiome. An ammonia-oxidizing Nitrososphaerota MAG B01, which accounted for up to 70% of the metagenome reads, dominated the sponge microbiomes. The B01 genome had a highly complex CRISPR array, which likely represents an advantageous evolution toward a symbiotic lifestyle and forceful ability to defend against phages. A sulfur-oxidizing Gammaproteobacteria species was the second most dominant symbiont, and a nitrite-oxidizing Nitrospirota species could also be detected, but with lower relative abundance. Bdellovibrio species represented by two MAGs, B11 and B12, were first reported as potential predatory symbionts in deep-sea glass sponges and have undergone dramatic genome reduction. Comprehensive functional analysis indicated that most of the sponge symbionts encoded CRISPR-Cas systems and eukaryotic-like proteins for symbiotic interactions with the host. Metabolic reconstruction further illustrated their essential roles in carbon, nitrogen, and sulfur cycles. In addition, diverse putative phages were identified from the sponge metagenomes. Our study expands the knowledge of microbial diversity, evolutionary adaption, and metabolic complementarity in deep-sea glass sponges.

7.
Microbiol Spectr ; 11(1): e0333822, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36511717

RESUMO

Deep-sea cold seeps are one of the most productive ecosystems that sustained by hydrocarbons carried by the fluid. Once the seep fluid ceases, the thriving autotrophic communities die out, terming as the extinct seep. But heterotrophic fauna can still survive even for thousands of years. The critical role of prokaryotes in active seeps are well defined, but their functions in extinct seeps are poorly understood to date. Here, we clarified the diversity, taxonomic specificity, interspecies correlation, and metabolic profiles of sediment prokaryotes at an extinct seep site of Haima cold seep, South China Sea. Alpha diversity of archaea significantly increased, while that of bacteria remained unchanged in extinct seep compared to active seep. However, archaea composition did not differ significantly at extinct seep from active or nonseep sites based on weighted-unifrac dissimilarity, while bacteria composition exhibited significant difference. Distribution of archaea and bacteria showed clear specificity to extinct seeps, indicating the unique life strategies here. Prokaryotes might live chemolithoautotrophically on cycling of inorganic carbon, sulfur, and nitrogen, or chemoorganotrophically on recycling of hydrocarbons. Notably, many of the extinct seep specific species and networked keystone lineages are classified as Proteobacteria. Regarding the functional diversity and metabolic flexibility of this clade, Proteobacteria is supposed to integrate the geochemical cycles and play a critical role in energy and resource supplement for microbiome in extinct seep. Collectively, our findings shed lights on the microbial ecology and functional diversity in extinct seeps, providing new understanding of biogeochemical cycling after fluid cessation. IMPORTANCE This research paper uncovered the potential mechanisms for microbiota mediated geochemical cycling in extinct cold seep, advancing our understanding in deep sea microbiology ecology.


Assuntos
Ecossistema , Sedimentos Geológicos , Sedimentos Geológicos/microbiologia , Carbono/metabolismo , Metano/metabolismo , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Hidrocarbonetos/metabolismo , Proteobactérias/metabolismo , Enxofre/metabolismo , Nitrogênio/metabolismo , Filogenia , RNA Ribossômico 16S
8.
J Integr Plant Biol ; 65(4): 950-966, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36453195

RESUMO

Halophytes complete their life cycles in saline environments. The recretohalophyte Limonium bicolor has evolved a specialized salt secretory structure, the salt gland, which excretes Na+ to avoid salt damage. Typical L. bicolor salt glands consist of 16 cells with four fluorescent foci and four secretory pores. Here, we describe a special type of salt gland at the base of the L. bicolor leaf petiole named bracelet salt glands due to their beaded-bracelet-like shape of blue auto-fluorescence. Bracelet salt glands contain more than 16 cells and more than four secretory pores. Leaf disc secretion measurements and non-invasive micro-test techniques indicated that bracelet salt glands secrete more salt than normal salt glands, which helps maintain low Na+ levels at the leaf blade to protect the leaf. Cytokinin treatment induced bracelet salt gland differentiation, and the developed ones showed no further differentiation when traced with a living fluorescence microscopy imager, even though new salt gland development and leaf expansion were observed. Transcriptome revealed a NAC transcription factor gene that participates in bracelet salt gland development, as confirmed by its genome editing and overexpression in L. bicolor. These findings shed light on bracelet salt gland development and may facilitate the engineering of salt-tolerant crops.


Assuntos
Plumbaginaceae , Animais , Plumbaginaceae/genética , Glândula de Sal , Folhas de Planta/genética , Transcriptoma , Sódio
9.
Int J Mol Sci ; 23(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36362412

RESUMO

Transmembrane proteins participate in various physiological activities in plants, including signal transduction, substance transport, and energy conversion. Although more than 20% of gene products are predicted to be transmembrane proteins in the genome era, due to the complexity of transmembrane domains they are difficult to reliably identify in the predicted protein, and they may have different overall three-dimensional structures. Therefore, it is challenging to study their biological function. In this review, we describe the typical structures of transmembrane proteins and their roles in plant growth, development, and stress responses. We propose a model illustrating the roles of transmembrane proteins during plant growth and response to various stresses, which will provide important references for crop breeding.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Melhoramento Vegetal , Desenvolvimento Vegetal
10.
Commun Biol ; 5(1): 1055, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36192584

RESUMO

Despite the environmental challenges and nutrient scarcity, the geographically isolated Challenger Deep in Mariana trench, is considered a dynamic hotspot of microbial activity. Hadal viruses are the least explored microorganisms in Challenger Deep, while their taxonomic and functional diversity and ecological impact on deep-sea biogeochemistry are poorly described. Here, we collect 13 sediment cores from slope and bottom-axis sites across the Challenger Deep (down to ~11 kilometers depth), and identify 1,628 previously undescribed viral operational taxonomic units at species level. Community-wide analyses reveals 1,299 viral genera and distinct viral diversity across the trench, which is significantly higher at the bottom-axis vs. slope sites of the trench. 77% of these viral genera have not been previously identified in soils, deep-sea sediments and other oceanic settings. Key prokaryotes involved in hadal carbon and nitrogen cycling are predicted to be potential hosts infected by these viruses. The detected putative auxiliary metabolic genes suggest that viruses at Challenger Deep could modulate the carbohydrate and sulfur metabolisms of their potential hosts, and stabilize host's cell membranes under extreme hydrostatic pressures. Our results shed light on hadal viral metabolic capabilities, contribute to understanding deep sea ecology and on functional adaptions of hadal viruses for future research.


Assuntos
Carbono , Solo , Carboidratos , Nitrogênio , Enxofre
11.
EMBO J ; 41(23): e111550, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36314841

RESUMO

Phosphoglycerate dehydrogenase (PHGDH) is a key serine biosynthesis enzyme whose aberrant expression promotes various types of tumors. Recently, PHGDH has been found to have some non-canonical functions beyond serine biosynthesis, but its specific mechanisms in tumorigenesis remain unclear. Here, we show that PHGDH localizes to the inner mitochondrial membrane and promotes the translation of mitochondrial DNA (mtDNA)-encoded proteins in liver cancer cells. Mechanistically, we demonstrate that mitochondrial PHGDH directly interacts with adenine nucleotide translocase 2 (ANT2) and then recruits mitochondrial elongation factor G2 (mtEFG2) to promote mitochondrial ribosome recycling efficiency, thereby promoting mtDNA-encoded protein expression and subsequent mitochondrial respiration. Moreover, we show that treatment with a mitochondrial translation inhibitor or depletion of mtEFG2 diminishes PHGDH-mediated tumor growth. Collectively, our findings uncover a previously unappreciated function of PHGDH in tumorigenesis acting via promotion of mitochondrial translation and bioenergetics.


Assuntos
Neoplasias Hepáticas , Fosfoglicerato Desidrogenase , Humanos , Fosfoglicerato Desidrogenase/genética , Fosfoglicerato Desidrogenase/metabolismo , Linhagem Celular Tumoral , Serina , Neoplasias Hepáticas/genética , Carcinogênese , DNA Mitocondrial
12.
Front Microbiol ; 13: 861795, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694283

RESUMO

The deep-sea hydrothermal vents (DSHVs) in the Southwest Indian Ridge (SWIR) are formed by specific geological settings. However, the community structure and ecological function of the microbial inhabitants on the sulfide chimneys of active hydrothermal vents remain largely unknown. In this study, our analyses of 16S rRNA gene amplicons and 16S rRNA metagenomic reads showed the dominance of sulfur-oxidizing Ectothiorhodospiraceae, Thiomicrorhabdus, Sulfurimonas, and Sulfurovum on the wall of two active hydrothermal chimneys. Compared with the inactive hydrothermal sediments of SWIR, the active hydrothermal chimneys lacked sulfur-reducing bacteria. The metabolic potentials of the retrieved 82 metagenome-assembled genomes (MAGs) suggest that sulfur oxidation might be conducted by Thiohalomonadales (classified as Ectothiorhodospiraceae based on 16S rRNA gene amplicons), Sulfurovaceae, Hyphomicrobiaceae, Thiotrichaceae, Thiomicrospiraceae, and Rhodobacteraceae. For CO2 fixation, the Calvin-Benson-Bassham and reductive TCA pathways were employed by these bacteria. In Thiohalomonadales MAGs, we revealed putative phytochrome, carotenoid precursor, and squalene synthesis pathways, indicating a possible capacity of Thiohalomonadales in adaptation to dynamics redox conditions and the utilization of red light from the hot hydrothermal chimneys for photolithotrophic growth. This study, therefore, reveals unique microbiomes and their genomic features in the active hydrothermal chimneys of SWIR, which casts light on ecosystem establishment and development in hydrothermal fields and the deep biosphere.

13.
PeerJ ; 10: e13241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433121

RESUMO

Candidate phylum KSB1 is composed of uncultured bacteria and has been reported across various environments. However, the phylogeny and metabolic potential of KSB1 have not been studied comprehensively. In this study, phylogenomic analysis of KSB1 genomes from public databases and eleven metagenome-assembled genomes (MAGs) from marine and hydrothermal sediments revealed that those genomes were clustered into four clades. Isolation source and relative abundance of KSB1 genomes showed that clade I was particularly abundant in bioreactor sludge. Genes related to dissimilatory reduction of nitrate to ammonia (DNRA), the last step of denitrification converting nitrous oxide to nitrogen and assimilatory sulfur reduction were observed in the expanded genomes of clade I, which may due to horizontal gene transfer that frequently occurred in bioreactor. Annotation and metabolic reconstruction of clades II and IV showed flagellum assembly and chemotaxis genes in the genomes, which may indicate that exploration and sensing for nutrients and chemical gradients are critical for the two clades in deep-sea and hydrothermal sediment. Metabolic potentials of fatty acids and short-chain hydrocarbons utilization were predicted in clades I and IV of KSB1. Collectively, phylogenomic and metabolic analyses of KSB1 clades provide insight into their anaerobic heterotrophic lifestyle and differentiation in potential ecological roles.


Assuntos
Bactérias , Metagenoma , Filogenia , Oxirredução , Bactérias/genética , Metagenoma/genética , Hidrocarbonetos/metabolismo
14.
mSystems ; 7(3): e0007722, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35430893

RESUMO

Thermoplasmatota have been widely reported in a variety of ecosystems, but their distribution and ecological role in marine sediments are still elusive. Here, we obtained four draft genomes affiliated with the former RBG-16-68-12 clade, which is now considered a new order, "Candidatus Yaplasmales," of the Thermoplasmatota phylum in sediments from the South China Sea. The phylogenetic trees based on the 16S rRNA genes and draft genomes showed that "Ca. Yaplasmales" archaea are composed of three clades: A, B, and C. Among them, clades A and B are abundantly distributed (up to 10.86%) in the marine anoxic sediment layers (>10-cm depth) of six of eight cores from 1,200- to 3,400-m depths. Metabolic pathway reconstructions indicated that all clades of "Ca. Yaplasmales" have the capacity for alkane degradation by predicted alkyl-succinate synthase. Clade A of "Ca. Yaplasmales" might be mixotrophic microorganisms for the identification of the complete Wood-Ljungdahl pathway and putative genes involved in the degradation of aromatic and halogenated organic compounds. Clades B and C were likely heterotrophic, especially with the potential capacity of the spermidine/putrescine and aromatic compound degradation, as suggested by a significant negative correlation between the concentrations of aromatic compounds and the relative abundances of clade B. The sulfide-quinone oxidoreductase and pyrophosphate-energized membrane proton pump were encoded by all genomes of "Ca. Yaplasmales," serving as adaptive strategies for energy production. These findings suggest that "Ca. Yaplasmales" might synergistically transform benthic pollutant and detrital organic matter, possibly playing a vital role in the marine and terrestrial sedimentary carbon cycle. IMPORTANCE Deep oceans receive large amounts of complex organic carbon and anthropogenic pollutants. The deep-sea sediments of the continental slopes serve as the biggest carbon sink on Earth. Particulate organic carbons and detrital proteins accumulate in the sediment. The microbially mediated recycling of complex organic carbon is still largely unknown, which is an important question for carbon budget in global oceans and maintenance of the deep-sea ecosystem. In this study, we report the prevalence (up to 10.86% of the microbial community) of archaea from a novel order of Thermoplasmatota, "Ca. Yaplasmales," in six of eight cores from 1,200- to 3,400-m depths in the South China Sea. We provide genomic evidence of "Ca. Yaplasmales" in the anaerobic microbial degradation of alkanes, aliphatic and monoaromatic hydrocarbons, and halogenated organic compounds. Our study identifies the key archaeal players in anoxic marine sediments, which are probably critical in recycling the complex organic carbon in global oceans.


Assuntos
Carbono , Microbiota , Carbono/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Archaea/genética , Genômica , Microbiota/genética , Compostos Orgânicos/metabolismo
15.
Nat Commun ; 13(1): 1515, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35314706

RESUMO

Hadal trenches are the deepest and most remote regions of the ocean. The 11-kilometer deep Challenger Deep is the least explored due to the technical challenges of sampling hadal depths. It receives organic matter and heavy metals from the overlying water column that accumulate differently across its V-shaped topography. Here, we collected sediments across the slope and bottom-axis of the Challenger Deep that enable insights into its in situ microbial communities. Analyses of 586 metagenome-assembled genomes retrieved from 37 metagenomes show distinct diversity and metabolic capacities between bottom-axis and slope sites. 26% of prokaryotic 16S rDNA reads in metagenomes were novel, with novelty increasing with water and sediment depths. These predominantly heterotrophic microbes can recycle macromolecules and utilize simple and complex hydrocarbons as carbon sources. Metagenome and metatranscriptome data support reduction and biotransformation of arsenate for energy gain in sediments that present a two-fold greater accumulation of arsenic compared to non-hadal sites. Complete pathways for anaerobic ammonia oxidation are predominantly identified in genomes recovered from bottom-axis sediments compared to slope sites. Our results expand knowledge of microbially-mediated elemental cycling in hadal sediments, and reveal differences in distribution of processes involved in nitrogen loss across the trench.


Assuntos
Bactérias , Microbiota , Bactérias/metabolismo , Sedimentos Geológicos , Processos Heterotróficos , Metagenoma/genética , Microbiota/genética , Água/metabolismo
16.
Environ Microbiol Rep ; 14(2): 308-319, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35199456

RESUMO

Reduced substrates produced by the serpentinization reaction under hydration of olivine may have fuelled biological processes on early Earth. To understand the adaptive strategies and carbon metabolism of the microbes in the serpentinizing ecosystems, we reconstructed 18 draft genomes representing dominant species of Omnitrophicaeota, Gammaproteobacteria and Methanobacteria from the Manleluag serpentinizing spring in Zambales, Philippines (hyperalkaline and rich in methane and hydrogen). Phylogenomics revealed that two genomes were affiliated with a candidate phylum NPL-UPA2 and the references of all our genomes were derived from ground waters, hot springs and the deep biosphere. C1 metabolism appears to be widespread as most of the genomes code for methanogenesis, CO oxidation and CO2 fixation. However, likely due to the low CO2 concentration and election acceptors, the biomass in the spring was extremely low (<103 cell/ml). Various Na+ and K+ transporters and Na+ -driving ATPases appear to be encoded by these genomes, suggesting that nutrient acquisition, bioenergetics and normal cytoplasmic pH were dependent on Na+ and K+ pumps. Our results advance our understanding of the metabolic potentials and bioenergetics of serpentinizing springs and provide a framework of the ecology of early Earth.


Assuntos
Euryarchaeota , Nascentes Naturais , Carbono/metabolismo , Ecossistema , Euryarchaeota/metabolismo , Nascentes Naturais/microbiologia , Filipinas
18.
Front Microbiol ; 12: 746111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690993

RESUMO

Gut dysbiosis may precede neonatal sepsis, but the association is still not well-understood. The goal of this study is to investigate the association between gut microbiota and neonatal sepsis, and to seek the evidence of colonization of pathogenic bacteria in the gut before evolving into an invasive infection. A prospective cohort study examined fecal microbiota composition in preterm infants with and without sepsis. Thirty-two very-low-birth-weight (VLBW) preterm infants and 10 healthy term infants as controls were enrolled. The fecal samples collected from the participants at the first, fourth, and seventh weeks of life underwent 16S rRNA amplicon sequencing for measurement of the diversity and composition of the microbiota. The bacterial isolates causing neonatal sepsis were genome sequenced. PCR was performed to confirm the translocation of the bacteria from the gut to the blood. The results showed that VLBW preterm infants with sepsis had lower microbial diversity in the gut at birth compared to preterm infants without sepsis and term infants. The composition of gut microbiome in preterm infants was similar to healthy terms at birth but evolved toward dysbiosis with increasing Proteobacteria and decreasing Firmicutes weeks later. The strain-specific PCR confirmed the presence of causative pathogens in the gut in 4 (40%) out of 10 VLBW preterms with sepsis before or at onset of sepsis, and persistence of the colonization for weeks after antibiotic treatment. The same bacterial strain could horizontally spread to cause infection in other infants. Prolonged antibiotic exposure significantly reduced beneficial Bifidobacterium and Lactobacillus in the gut. In conclusion, preterm infants with gut dysbiosis are at risk for neonatal sepsis, and the causative pathogens may be from the gut and persist to spread horizontally. The association of increased Proteobacteria abundance and decrease in microbiome diversity suggests the need for interventions targeting the gut microbiome to prevent dysbiosis and sepsis in VLBW preterm infants.

19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1436-1449, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627422

RESUMO

OBJECTIVE: LncRNA ITGB2-AS1 has been found to play important roles in the occurrence and development of human solid tumors. However, its role in hematological diseases, especially acute myeloid leukemia (AML), remains unclear. The aim of this study was to identify the expression pattern of ITGB2-AS1 in AML patients and to further explore its clinical significance. METHODS: ITGB2-AS1 expression was analyzed in public datasets (including TCGA and GSE63270) and further validated in a cohort of 109 AML patients by real-time quantitative PCR (RT-qPCR). RESULTS: The level of ITGB2-AS1 was up-regulated among two independent cohorts (TCGA, P<0.05; GSE63270, P<0.05), which was confirmed by the data from 109 AML patients enrolled in this study (P<0.05). Clinically, high ITGB2-AS1 expression was associated with older age (P=0.023) and lower complete remission (CR) rate (P=0.005). Multivariate analysis identified that high ITGB2-AS1 expression was an independent prognostic factor not only for CR rate (P=0.027) but also for overall survival (OS) time (P=0.011), and ITGB2-AS1 was positively correlated with ITGB2 expression in both TCGA (r=0.74, P<0.001) and clinical data detected in this study (r=0.881, P<0.001). High ITGB2 expression was also associated with older age (P=0.02) and lower CR rate (P=0.020). Moreover, high ITGB2 expression predicted worse OS (P=0.028). CONCLUSION: ITGB2-AS1 is overexpressed in AML and predicts poor prognosis in AML patients.


Assuntos
Leucemia Mieloide Aguda , RNA Longo não Codificante , Idoso , Humanos , Leucemia Mieloide Aguda/genética , Prognóstico , RNA Longo não Codificante/genética
20.
Environ Microbiol ; 23(11): 6844-6858, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34622529

RESUMO

Microbial sulfate reduction is largely associated with anaerobic methane oxidation and alkane degradation in sulfate-methane transition zone (SMTZ) of deep-sea cold seeps. How the sulfur cycling is mediated by microbes near SMTZ has not been fully understood. In this study, we detected a shallow SMTZ in three of eight sediment cores sampled from two cold seep areas in the South China Sea. One hundred ten genomes representing sulfur-oxidizing bacteria (SOB) and sulfur-reducing bacteria (SRB) strains were identified from three SMTZ-bearing cores. In the layers above SMTZ, SOB were mostly constituted by Campylobacterota, Gammaproteobacteria and Alphaproteobacteria that probably depended on nitrogen oxides and/or oxygen for oxidation of sulfide and thiosulfate in near-surface sediment layers. In the layers below the SMTZ, the deltaproteobacterial SRB genomes and metatranscriptomes revealed CO2 fixation by Wood-Ljungdahl pathway, sulfate reduction and nitrogen fixation for syntrophic or fermentative lifestyle. A total of 68% of the metagenome assembled genomes were not adjacent to known species in a phylogenomic tree, indicating a high diversity of bacteria involved in sulfur cycling. With the large number of genomes for SOB and SRB, our study uncovers the microbial populations that potentially mediate sulfur metabolism and associated carbon and nitrogen cycles, which sheds light on complex biogeochemical processes in deep-sea environments.


Assuntos
Metano , Sulfatos , Sedimentos Geológicos/microbiologia , Metano/metabolismo , Oxirredução , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Sulfatos/metabolismo , Enxofre/metabolismo
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