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1.
Nucleic Acids Res ; 52(13): 7556-7571, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38783136

RESUMEN

Non-genetic variations derived from expression noise at transcript or protein levels can result in cell-to-cell heterogeneity within an isogenic population. Although cells have developed strategies to reduce noise in some cellular functions, this heterogeneity can also facilitate varying levels of regulation and provide evolutionary benefits in specific environments. Despite several general characteristics of cellular noise having been revealed, the detailed molecular pathways underlying noise regulation remain elusive. Here, we established a dual-fluorescent reporter system in Saccharomyces cerevisiae and performed experimental evolution to search for mutations that increase expression noise. By analyzing evolved cells using bulk segregant analysis coupled with whole-genome sequencing, we identified the histone deacetylase Hos2 as a negative noise regulator. A hos2 mutant down-regulated multiple ribosomal protein genes and exhibited partially compromised protein translation, indicating that Hos2 may regulate protein expression noise by modulating the translation machinery. Treating cells with translation inhibitors or introducing mutations into several Hos2-regulated ribosomal protein genes-RPS9A, RPS28B and RPL42A-enhanced protein expression noise. Our study provides an effective strategy for identifying noise regulators and also sheds light on how cells regulate non-genetic variation through protein translation.


Asunto(s)
Regulación Fúngica de la Expresión Génica , Histona Desacetilasas , Biosíntesis de Proteínas , Proteínas Ribosómicas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Histona Desacetilasas/metabolismo , Histona Desacetilasas/genética , Mutación , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
2.
Glycoconj J ; 40(3): 295-303, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37052731

RESUMEN

Sialylation is an important terminal modification of glycoconjugates that mediate diverse functions in physiology and disease. In this review we focus on how altered cell surface sialylation status is sensed by cytosolic galectins when the integrity of intracellular vesicles or organelles is compromised to expose luminal glycans to the cytosolic milieu, and how this impacts galectin-mediated cellular responses. In addition, we discuss the roles of mammalian sialidases on the cell surface, in the organelle lumen and cytosol, and raise the possibility that intracellular glycan processing may be critical in controlling various galectin-mediated responses when cells encounter stress.


Asunto(s)
Galectinas , Polisacáridos , Animales , Galectinas/metabolismo , Citosol/metabolismo , Polisacáridos/metabolismo , Glicoconjugados/metabolismo , Orgánulos , Mamíferos/metabolismo
3.
J Environ Manage ; 346: 118978, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37742566

RESUMEN

Owing to the strong C-F bond in nature and the rigidity of the poly-fluoroalkyl chain, perfluorooctanoic acid (PFOA) is difficult to be eliminated by reactive species and microbes in environments, thus posing a serious threat to ecosystems. Vitamin B12 as a cofactor for enzymes, and biochar as the electron providers and conductors, were integrated to enhance PFOA biodegradation. The raw material of biochar was the sludge after dewatering by adding 50 mg/g DS of Fe(III). After pyrolysis under high temperature (800 °C), biochar (SC800) detected high content of Fe(II) (197.64 mg/g) and abundant oxygen-containing functional groups, thus boosting PFOA biodegradation via donating electrons. 99.9% of PFOA could be removed within 60 d as 0.1 g/L SC800 was presented in the microbial systems containing vitamin B12. Moreover, vitamin B12 facilitated the evolution of Sporomusa which behaved the deflorination. Via providing reactive sites and mediating direct inter-species electron transfer (DIET), SC800 boosted PFOA biodegradation. Corresponding novel results in the present study could guide the development of bioremediation technologies for PFOA-polluted sites.


Asunto(s)
Hierro , Aguas del Alcantarillado , Biodegradación Ambiental , Electrones , Vitamina B 12 , Ecosistema , Carbón Orgánico/química , Vitaminas
4.
J Environ Manage ; 347: 119058, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37757689

RESUMEN

Soil and groundwater contamination caused by petroleum hydrocarbons is a severe environmental problem. In this study, a novel electrolyzed catalytic system (ECS) was developed to produce nanobubble-contained electrolyzed catalytic (NEC) water for the remediation of petroleum-hydrocarbon-contaminated soils and groundwater. The developed ECS applied high voltage (220 V) with direct current, and titanium electrodes coated with iridium dioxide were used in the system. The developed ECS prototype contained 21 electrode pairs (with a current density of 20 mA/cm2), which were connected in series to significantly enhance the hydroxyl radical production rate. Iron-copper hybrid oxide catalysts were laid between each electrode pair to improve the radical generation efficiency. The electron paramagnetic resonance (EPR) and Rhodamine B (RhB) methods were applied for the generated radical species and concentration determination. During the operation of the ECS, high concentrations of nanobubbles (nanobubble density = 3.7 × 109 particles/mL) were produced due to the occurrence of the cavitation mechanism. Because of the negative zeta potential and nano-scale characteristics of nanobubbles (mean diameter = 28 nm), the repelling force would prevent the occurrence of bubble aggregations and extend their lifetime in NEC water. The radicals produced after the bursting of the nanobubbles would be beneficial for the increase of the radical concentration and subsequent petroleum hydrocarbon oxidation. The highly oxidized NEC water (oxidation-reduction potential = 887 mV) could be produced with a radical concentration of 9.5 × 10-9 M. In the pilot-scale study, the prototype system was applied to clean up petroleum-hydrocarbon polluted soils at a diesel-oil spill site via an on-site slurry-phase soil washing process. The total petroleum hydrocarbon (TPH)-contaminated soils were excavated and treated with the NEC water in a slurry-phase reactor. Results show that up to 74.4% of TPH (initial concentration = 2846 mg/kg) could be removed from soils after four rounds of NEC water treatment (soil and NEC water ratio for each batch = 10 kg: 40 L and reaction time = 10 min). Within the petroleum-hydrocarbon plume, one remediation well (RW) and two monitor wells (located 1 m and 3 m downgradient of the RW) were installed along the groundwater flow direction. The produced NEC water was injected into the RW and the TPH concentrations in groundwater (initial concentrations = 12.3-15.2 mg/L) were assessed in these three wells. Compared to the control well, TPH concentrations in RW and MW1 dropped to below 0.4 and 2.1 mg/L after 6 m3 of NEC water injection in RW, respectively. Results from the pilot-scale study indicate that the NEC water could effectively remediate TPH-contaminated soils and groundwater without secondary pollution production. The main treatment mechanisms included (1) in situ chemical oxidation via produced radicals, (2) desorption of petroleum hydrocarbons from soil particles due to the dispersion of nanobubbles into soil pores, and (3) enhanced TPH oxidation due to produced radicals and energy after nanobubble bursting.


Asunto(s)
Agua Subterránea , Petróleo , Contaminantes del Suelo , Contaminación Ambiental , Hidrocarburos , Suelo , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Microbiología del Suelo
5.
J Environ Manage ; 339: 117947, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37075632

RESUMEN

Cr(VI) bioreduction has become a remedial alternative for Cr(VI)-polluted site cleanup. However, lack of appropriate Cr(VI)-bioreducing bacteria limit the field application of the in situ bioremediation process. In this study, two different immobilized Cr(VI)-bioreducing bacterial consortia using novel immobilization agents have been developed for Cr(VI)-polluted groundwater remediation: (1) granular activated carbon (GAC) + silica gel + Cr(VI)-bioreducing bacterial consortia (GSIB), and (2) GAC + sodium alginate (SA) + polyvinyl alcohol (PVA) + Cr(VI)-bioreducing bacterial consortia (GSPB). Moreover, two unique substrates [carbon-based agent (CBA) and emulsified polycolloid substrate (EPS)] were developed and used as the carbon sources for Cr(VI) bioreduction enhancement. The microbial diversity, dominant Cr-bioreducing bacteria, and changes of Cr(VI)-reducing genes (nsfA, yieF, and chrR) were analyzed to assess the effectiveness of Cr(VI) bioreduction. Approximately 99% of Cr(VI) could be bioreduced in microcosms with GSIB and CBA addition after 70 days of operation, which caused increased populations of total bacteria, nsfA, yieF, and chrR from 2.9 × 108 to 2.1 × 1012, 4.2 × 104 to 6.3 × 1011, 4.8 × 104 to 2 × 1011, and 6.9 × 104 to 3.7 × 107 gene copies/L. In microcosms with CBA and suspended bacteria addition (without bacterial immobilization), the Cr(VI) reduction efficiency dropped to 60.3%, indicating that immobilized Cr-bioreducing bacteria supplement could enhance Cr(VI) bioreduction. Supplement of GSPB led to a declined bacterial growth due to the cracking of the materials. The addition of GSIB and CBA could establish a reduced condition, which favored the growth of Cr(VI)-reducing bacteria. The Cr(VI) bioreduction efficiency could be significantly improved through adsorption and bioreduction mechanisms, and production of Cr(OH)3 precipitates confirmed the occurrence of Cr(VI) reduction. The main Cr-bioreducing bacteria included Trichococcus, Escherichia-Shigella, and Lactobacillus. Results suggest that the developed GSIB bioremedial system could be applied to cleanup Cr(VI)-polluted groundwater effectively.


Asunto(s)
Cromo , Agua Subterránea , Oxidación-Reducción , Cromo/análisis , Biodegradación Ambiental , Bacterias/genética
6.
Glycobiology ; 32(9): 760-777, 2022 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-35789267

RESUMEN

Galectin-3 (GAL3) is a ß-galactoside-binding lectin expressed in CD4 T cells infected with human immunodeficiency virus-1 (HIV-1). GAL3 promotes HIV-1 budding by associating with ALIX and Gag p6. GAL3 has been shown to localize in membrane lipid rafts in dendritic cells and positively regulate cell migration. HIV-1 spreads between T cells by forming supramolecular structures (virological synapses [VSs]), whose integrity depends on lipid rafts. Here, we addressed the potential role of GAL3 in cell-to-cell transmission of HIV-1 in CD4 T cells. GAL3 expressed in donor cells was more important for facilitating HIV-1 cell-to-cell transfer than GAL3 expressed in target cells. GAL3 was found to be co-transferred with Gag from HIV-1-positive donor to HIV-1-negative target T cells. HIV-1 infection induced translocation of GAL3 together with Gag to the cell-cell interfaces and colocalize with GM1, where GAL3 facilitated VS formation. GAL3 regulated the coordinated transfer of Gag and flotillin-1 into plasma membrane fractions. Finally, depletion of GAL3 reduced the cholesterol levels in membrane lipid rafts in CD4 T cells. These findings provide evidence that endogenous GAL3 stimulates lipid raft components and facilitates intercellular HIV-1 transfer among CD4 T cells, offering another pathway by which GAL3 regulates HIV-1 infection. These findings may inform the treatment of HIV-1 infection based on targeting GAL3 to modulate lipid rafts.


Asunto(s)
Infecciones por VIH , VIH-1 , Proteínas Sanguíneas , Linfocitos T CD4-Positivos/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Galectinas , Humanos , Lípidos de la Membrana/análisis , Lípidos de la Membrana/metabolismo , Microdominios de Membrana/química
7.
Circ Res ; 127(2): 207-224, 2020 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-32228120

RESUMEN

RATIONALE: One goal of cardiac tissue engineering is the generation of a living, human pump in vitro that could replace animal models and eventually serve as an in vivo therapeutic. Models that replicate the geometrically complex structure of the heart, harboring chambers and large vessels with soft biomaterials, can be achieved using 3-dimensional bioprinting. Yet, inclusion of contiguous, living muscle to support pump function has not been achieved. This is largely due to the challenge of attaining high densities of cardiomyocytes-a notoriously nonproliferative cell type. An alternative strategy is to print with human induced pluripotent stem cells, which can proliferate to high densities and fill tissue spaces, and subsequently differentiate them into cardiomyocytes in situ. OBJECTIVE: To develop a bioink capable of promoting human induced pluripotent stem cell proliferation and cardiomyocyte differentiation to 3-dimensionally print electromechanically functional, chambered organoids composed of contiguous cardiac muscle. METHODS AND RESULTS: We optimized a photo-crosslinkable formulation of native ECM (extracellular matrix) proteins and used this bioink to 3-dimensionally print human induced pluripotent stem cell-laden structures with 2 chambers and a vessel inlet and outlet. After human induced pluripotent stem cells proliferated to a sufficient density, we differentiated the cells within the structure and demonstrated function of the resultant human chambered muscle pump. Human chambered muscle pumps demonstrated macroscale beating and continuous action potential propagation with responsiveness to drugs and pacing. The connected chambers allowed for perfusion and enabled replication of pressure/volume relationships fundamental to the study of heart function and remodeling with health and disease. CONCLUSIONS: This advance represents a critical step toward generating macroscale tissues, akin to aggregate-based organoids, but with the critical advantage of harboring geometric structures essential to the pump function of cardiac muscle. Looking forward, human chambered organoids of this type might also serve as a test bed for cardiac medical devices and eventually lead to therapeutic tissue grafting.


Asunto(s)
Bioimpresión/métodos , Diferenciación Celular , Miocitos Cardíacos/fisiología , Organoides/fisiología , Ingeniería de Tejidos/métodos , Potenciales de Acción , Proliferación Celular , Células Cultivadas , Proteínas de la Matriz Extracelular/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/fisiología , Contracción Miocárdica , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Organoides/citología , Organoides/metabolismo
8.
J Org Chem ; 87(22): 15327-15332, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36302512

RESUMEN

Hexamethyldisilazane was reacted with formamides to generate N,N-disubstituent formimidamide, after which a reaction with sulfonamides was induced to form sulfonylformamidines. This protocol can be applied for arylformamidine formation in which anilines are used as substrates under optimized conditions. The advantages of this method are high efficiency, structural diversity in products with good yields, and applicability in large-scale operations.


Asunto(s)
Formamidas , Compuestos de Organosilicio , Formamidas/química , Aminas/química , Sulfonamidas/química , Sulfanilamida
9.
Int J Mol Sci ; 23(22)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36430922

RESUMEN

Bionic-engineered tissues have been proposed for testing the performance of cardiovascular medical devices and predicting clinical outcomes ex vivo. Progress has been made in the development of compliant electronics that are capable of monitoring treatment parameters and being coupled to engineered tissues; however, the scale of most engineered tissues is too small to accommodate the size of clinical-grade medical devices. Here, we show substantial progress toward bionic tissues for evaluating cardiac ablation tools by generating a centimeter-scale human cardiac disk and coupling it to a hydrogel-based soft-pressure sensor. The cardiac tissue with contiguous electromechanical function was made possible by our recently established method to 3D bioprint human pluripotent stem cells in an extracellular matrix-based bioink that allows for in situ cell expansion prior to cardiac differentiation. The pressure sensor described here utilized electrical impedance tomography to enable the real-time spatiotemporal mapping of pressure distribution. A cryoablation tip catheter was applied to the composite bionic tissues with varied pressure. We found a close correlation between the cell response to ablation and the applied pressure. Under some conditions, cardiomyocytes could survive in the ablated region with more rounded morphology compared to the unablated controls, and connectivity was disrupted. This is the first known functional characterization of living human cardiomyocytes following an ablation procedure that suggests several mechanisms by which arrhythmia might redevelop following an ablation. Thus, bionic-engineered testbeds of this type can be indicators of tissue health and function and provide unique insight into human cell responses to ablative interventions.


Asunto(s)
Biónica , Ablación por Catéter , Humanos , Ablación por Catéter/métodos , Miocitos Cardíacos/metabolismo , Ingeniería de Tejidos/métodos , Arritmias Cardíacas/metabolismo
10.
J Environ Manage ; 311: 114836, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35272161

RESUMEN

In this study, the developed innovative immobilized Clostridium butyricum (ICB) (hydrogen-producing bacteria) column scheme was applied to cleanup chlorinated-ethene [mainly cis-1,2-dichloroethene (cis-DCE)] polluted groundwater in situ via the anaerobic reductive dechlorinating processes. The objectives were to assess the effectiveness of the field application of ICB scheme on the cleanup of cis-DCE polluted groundwater, and characterize changes of microbial communities after ICB application. Three remediation wells and two monitor wells were installed within the cis-DCE plume. In the remediation well, a 1.2-m PVC column (radius = 2.5 cm) (filled with ICB beads) and 20 L of slow polycolloid-releasing substrate (SPRS) were supplied for hydrogen production enhancement and primary carbon supply, respectively. Groundwater samples from remediation and monitor wells were analyzed periodically for cis-DCE and its degradation byproducts, microbial diversity, reductive dehalogenase, and geochemical indicators. Results reveal that cis-DCE was significantly decreased within the ICB and SPRS influence zone. In a remediation well with ICB injection, approximately 98.4% of cis-DCE removal (initial concentration = 1.46 mg/L) was observed with the production of ethene (end-product of cis-DCE dechlorination) after 56 days of system operation. Up to 0.72 mg/L of hydrogen was observed in remediation wells after 14 days of ICB and SPRS introduction, which corresponded with the increased population of Dehalococcoides spp. (Dhc) (increased from 3.76 × 103 to 5.08 × 105 gene copies/L). Results of metagenomics analyses show that the SPRS and ICB introduction caused significant impacts on the bacterial communities, and increased Bacteroides, Citrobacter, and Desulfovibrio populations were observed, which had significant contributions to the reductive dechlorination of cis-DCE. Application of ICB could effectively result in increased populations of Dhc and RDase genes, which corresponded with improved dechlorination of cis-DCE and vinyl chloride. Introduction of ICB and SPRS could be applied as a potential in situ remedial option to enhance anaerobic dechlorination efficiencies of chlorinated ethenes.

11.
Glycobiology ; 31(9): 1230-1238, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34132764

RESUMEN

Glycosylation is important for biological functions of proteins and greatly affected by diseases. Exploring the glycosylation profile of the protein-specific glycosylation and/or the site-specific glycosylation may help understand disease etiology, differentiate diseases and ultimately develop therapeutics. Patients with multiple sclerosis (MS) and patients with neuromyelitis optica spectrum disorder (NMOSD) are sometimes difficult to differentiate due to the similarity in their clinical symptoms. The disease-related glycosylation profiles of MS and NMOSD have not yet been well studied. Here, we analyzed site-specific glycan profiles of serum proteins of these patients by using a recently developed mass spectrometry technique. A total of 286 glycopeptides from 49 serum glycoproteins were quantified and compared between healthy controls (n = 6), remitting MS (n = 45) and remitting NMOSD (n = 23) patients. Significant differences in the levels of site-specific N-glycans on inflammation-associated components [IgM, IgG1, IgG2, complement components 8b (CO8B) and attractin], central nerve system-damage-related serum proteins [apolipoprotein D (APOD), alpha-1-antitrypsin, plasma kallikrein and ADAMTS-like protein 3] were observed among three study groups. We furthered demonstrated that site-specific N-glycans on APOD on site 98, CO8B on sites 243 and 553 are potential markers to differentiate MS from NMOSD with an area under receiver operating curve value > 0.75. All these observations indicate that remitting MS or NMOSD patients possess a unique disease-associated glyco-signature in their serum proteins. We conclude that monitoring one's serum protein glycan profile using this high-throughput analysis may provide an additional diagnostic criterion for differentiating diseases, monitoring disease status and estimating response-to-treatment effect.


Asunto(s)
Esclerosis Múltiple , Neuromielitis Óptica , Biomarcadores , Humanos , Inmunoglobulina G , Esclerosis Múltiple/diagnóstico , Neuromielitis Óptica/diagnóstico , Proyectos Piloto
12.
J Biomed Sci ; 28(1): 16, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33663512

RESUMEN

Galectins are animal lectins that recognize carbohydrates and play important roles in maintaining cellular homeostasis. Recent studies have indicated that under a variety of challenges, intracellular galectins bind to host glycans displayed on damaged endocytic vesicles and accumulate around these damaged organelles. Accumulated galectins then engage cellular proteins and subsequently control cellular responses, such as autophagy. In this review, we have summarized the stimuli that lead to the accumulation of galectins, the molecular mechanisms of galectin accumulation, and galectin-mediated cellular responses, and elaborate on the differential regulatory effects among galectins.


Asunto(s)
Autofagia , Galectinas/metabolismo , Polisacáridos/metabolismo , Animales , Metabolismo de los Hidratos de Carbono , Humanos
13.
Environ Res ; 187: 109629, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32460090

RESUMEN

Trichloroethylene (TCE) is a frequently found organic contaminant in polluted-groundwater. In this microcosm study, effects of hydrogen-producing bacteria [Clostridium butyricum (Clostridium sp.)] and inhibitor of sulfate-reducing bacteria (SRB) addition on the enhancement of TCE dechlorination were evaluated. Results indicate that Clostridium sp. supplement could effectively enhance TCE reductive dechlorination (97.4% of TCE removal) due to increased hydrogen concentration and Dehalococcoides (DHC) populations (increased to 1 × 104 gene copies/L). However, addition of Clostridium sp. also caused the increase in dsrA (dissimilatory sulfide reductase subunit A) (increased to 2 × 108 gene copies/L), and thus, part of the hydrogen was consumed by SRB, which would limit the effective application of hydrogen by DHC. Control of Clostridium sp. addition is a necessity to minimize the adverse impact of Clostridium sp. on DHC growth. Ferric citrate caused the slight raise of the oxidation-reduction state, which resulted in growth inhibition of SRB. Molybdate addition inhibited the growth of SRB, and thus, the dsrA concentrations (dropped from 4 × 107 to 9 × 105 gene copies/L) and sulfate reduction efficiency were decreased. Increased DHC populations (increased from 8 × 103 to 1 × 105 gene copies/L) were due to increased available hydrogen (increased from 0 to 2 mg/L), which enhanced TCE dechlorination (99.3% TCE removal). Metagenomic analyses show that a significant microbial diversity was detected in microcosms with different treatments. Clostridium sp., ferric citrate, and molybdate addition caused a decreased SRB communities and increased fatty acid production microbial communities (increased from 4.9% to 20.2%), which would be beneficial to the hydrogen production and TCE dechlorination processes.


Asunto(s)
Tricloroetileno , Contaminantes Químicos del Agua , Bacterias , Biodegradación Ambiental , Sulfatos , Contaminantes Químicos del Agua/análisis
14.
Environ Res ; 184: 109296, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32146214

RESUMEN

Hexavalent chromium (Cr6+) is a commonly found heavy metal at polluted groundwater sites. In this study, the effectiveness of Cr6+ bioreduction by the chromium-reducing bacteria was evaluated to remediate Cr6+-contaminated groundwater. Microcosms were constructed using indigenous microbial consortia from a Cr6+-contaminated aquifer as the inocula, and slow-releasing emulsified polycolloid-substrate (ES), cane molasses (CM), and nutrient broth (NB) as the primary substrates. The genes responsible for the bioreduction of Cr6+ and variations in bacterial diversity were evaluated using metagenomics assay. Complete Cr6+ reduction via the biological mechanism was observed within 80 days using CM as the carbon source under anaerobic processes with the increased trivalent chromium (Cr3+) concentrations. Cr6+ removal efficiencies were 83% and 59% in microcosms using ES and NB as the substrates, respectively. Increased bacterial communities associated with Cr6+ bioreduction was observed in microcosms treated with CM and ES. Decreased bacterial communities were observed in NB microcosms. Compared to ES, CM was more applicable by indigenous Cr6+ reduction bacteria and resulted in effective Cr6+ bioreduction, which was possibly due to the growth of Cr6+-reduction related bacteria including Sporolactobacillus, Clostridium, and Ensifer. While NB was applied for specific bacterial selection, it might not be appropriate for electron donor application. These results revealed that substrate addition had significant impact on microbial diversities, which affected Cr6+ bioreduction processes. Results are useful for designing a green and sustainable bioreduction system for Cr6+-polluted groundwater remediation.


Asunto(s)
Cromo , Agua Subterránea , Biodegradación Ambiental , Cromo/análisis , Cromo/metabolismo , Oxidación-Reducción
15.
Glycobiology ; 30(1): 49-57, 2019 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-31553041

RESUMEN

Galectins are ß-galactoside-binding animal lectins primarily found in the cytosol, while their carbohydrate ligands are mainly distributed in the extracellular space. Cytosolic galectins are anticipated to accumulate on damaged endocytic vesicles through binding to glycans initially displayed on the cell surface and subsequently located in the lumen of the vesicles, and this can be followed by cellular responses. To facilitate elucidation of the mechanism underlying this process, we adopted a model system involving induction of endocytic vesicle damage with light that targets the endocytosed amphiphilic photosensitizer disulfonated aluminum phthalocyanine. We demonstrate that the levels of galectins around damaged endosomes are dependent on the composition of carbohydrates recognized by the proteins. By super resolution imaging, galectin-3 and galectin-8 aggregates were found to be distributed in distinct microcompartments. Importantly, galectin accumulation is significantly affected when cell surface glycans are altered. Furthermore, accumulated galectins can direct autophagy adaptor proteins toward damaged endocytic vesicles, which are also significantly affected following alteration of cell surface glycans. We conclude that cytosolic galectins control cellular responses reflect dynamic modifications of cell surface glycans.


Asunto(s)
Carbohidratos/química , Galectinas/metabolismo , Células A549 , Animales , Células CHO , Comunicación Celular , Células Cultivadas , Cricetulus , Endosomas/metabolismo , Galectinas/química , Humanos
16.
Glycobiology ; 28(6): 392-405, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29800364

RESUMEN

While glycans are generally displayed on the cell surface or confined within the lumen of organelles, they can become exposed to the cytosolic milieu upon disruption of organelle membrane by various stresses or pathogens. Galectins are a family of ß-galactoside-binding animal lectins synthesized and predominantly localized in the cytosol. Recent research indicates that some galectins may act as "danger signal sensors" by detecting unusual exposure of glycans to the cytosol. Galectin-8 was shown to promote antibacterial autophagy by recognizing host glycans on ruptured vacuolar membranes and interacting with the autophagy adaptor protein NDP52. Galectin-3 also accumulates at damaged phagosomes containing bacteria; however, its functional consequence remains obscure. By studying mouse macrophages infected with Listeria monocytogenes (LM), we showed that endogenous galectin-3 protects intracellular LM by suppressing the autophagic response through a host N-glycan-dependent mechanism. Knock out of the galectin-3 gene resulted in enhanced LC3 recruitment to LM and decreased bacterial replication, a phenotype recapitulated when Galectin-8-deficient macrophages were depleted of N-glycans. Moreover, we explored the concept that alterations in cell surface glycosylation by extracellular factors can be deciphered by cytosolic galectins during the process of phagocytosis/endocytosis, followed by rupture of phagosomal/endosomal membrane. Notably, treatment of cells with sialidase, which removes sialic acid from glycans, resulted in increased galectin-3 accumulation and decreased galectin-8 recruitment at damaged phagosomes, and led to a stronger anti-autophagic response. Our findings demonstrate that cytosolic galectins may sense changes in glycosylation at the cell surface and modulate cellular response through differential recognition of glycans on ruptured phagosomal membranes.


Asunto(s)
Autofagia , Galectina 3/metabolismo , Galectinas/metabolismo , Fagosomas/metabolismo , Polisacáridos/metabolismo , Animales , Línea Celular , Células Cultivadas , Citosol/metabolismo , Galectina 3/genética , Galectinas/genética , Listeria monocytogenes/patogenicidad , Macrófagos/metabolismo , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/metabolismo , Unión Proteica
17.
Toxicol Appl Pharmacol ; 279(3): 322-330, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-24998975

RESUMEN

Bladder cancer is highly recurrent following specific transurethral resection and intravesical chemotherapy, which has prompted continuing efforts to develop novel therapeutic agents and early-stage diagnostic tools. Specific changes in protein expression can provide a diagnostic marker. In our present study, we investigated changes in protein expression during urothelial carcinogenesis. The carcinogen BBN was used to induce mouse bladder tumor formation. Mouse bladder mucosa proteins were collected and analyzed by 2D electrophoresis from 6 to 20 weeks after commencing continuous BBN treatment. By histological examination, the connective layer of the submucosa showed gradual thickening and the number of submucosal capillaries gradually increased after BBN treatment. At 12-weeks after the start of BBN treatment, the urothelia became moderately dysplastic and tumors arose after 20-weeks of treatment. These induced bladder lesions included carcinoma in situ and connective tissue invasive cancer. In protein 2D analysis, the sequentially downregulated proteins from 6 to 20 weeks included GSTM1, L-lactate dehydrogenase B chain, keratin 8, keratin 18 and major urinary proteins 2 and 11/8. In contrast, the sequentially upregulated proteins identified were GSTO1, keratin 15 and myosin light polypeptide 6. Western blotting confirmed that GSTM1 and NQO-1 were decreased, while GSTO1 and Sp1 were increased, after BBN treatment. In human bladder cancer cells, 5-aza-2'-deoxycytidine increased the GSTM1 mRNA and protein expression. These data suggest that the downregulation of GSTM1 in the urothelia is a biomarker of bladder carcinogenesis and that this may be mediated by DNA CpG methylation.


Asunto(s)
Butilhidroxibutilnitrosamina/toxicidad , Carcinógenos/toxicidad , Glutatión Transferasa/biosíntesis , Neoplasias de la Vejiga Urinaria/inducido químicamente , Neoplasias de la Vejiga Urinaria/genética , Animales , Antimetabolitos Antineoplásicos/farmacología , Azacitidina/análogos & derivados , Azacitidina/farmacología , Western Blotting , Peso Corporal/efectos de los fármacos , Línea Celular Tumoral , Colorantes , Decitabina , Regulación hacia Abajo/efectos de los fármacos , Electroforesis en Gel Bidimensional , Femenino , Glutatión Transferasa/efectos de los fármacos , Glutatión Transferasa/genética , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Membrana Mucosa/efectos de los fármacos , Membrana Mucosa/ultraestructura , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/biosíntesis , Reacción en Cadena en Tiempo Real de la Polimerasa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/patología
18.
J Hazard Mater ; 480: 135903, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39307012

RESUMEN

Microbial dehalogenation, using obligate and facultative organohalide-respiring bacteria (OHRB), has been widely used to remediate halohydrocarbon-polluted sites. Owing to the scarcity of OHRB, and poor efficiency in H2-mediating interspecies electron transfer, microbial dehalogenation relying on OHRB is easily disturbed by Fe(III), sulfate, and nitrate as electron competitors. In the present study, pyrogenic carbon, featuring electron snorkeling, was introduced into the process of microbial dehalogenation, which facilitated the electron transfer from electro-active microbes to halohydrocarbon, then invigorating dehalogenation. As a consequence, fine dehalogenation of trichloroethene (TCE, as representative halohydrocarbon) was obtained, expressed as the nearly complete diminishment of 150 µmol L-1 TCE and the sequestration of high contents of ethene (72.2-122.3 µmol L-1 within 80 d). Such fine dehalogenation was ascribed to the synergy between pyrogenic carbon and electro-active microbes. Multiple microbes in mixed cultures, including Clostridium sp., Sporanaerobacter, Sedimentibacter, Paraclostridium, and Tissierella, stimulated TCE dehalogenation by providing electrons to pyrogenic carbon. Redox moieties on pyrogenic carbon enabled it to snorkel electrons, which facilitated the electron transfer from electro-active microbes to TCE, consequently invigorating TCE dehalogenation. Such microbial dehalogenation free of OHRB demonstrates the effectiveness of a novel strategy for remediating halohydrocarbon-polluted environments.

19.
J Hazard Mater ; 477: 135279, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39047569

RESUMEN

The weathering process can cause the volatilization of light components in crude oil, leading to the accumulation of total petroleum hydrocarbons (TPH) in weathered oil field soils. These TPH compounds are relatively resistant to biodegradation, posing a significant environmental hazard by contributing to soil degradation. TPH represents a complex mixture of petroleum-based hydrocarbons classified as persistent organic pollutants in soil and groundwater. The release of TPH pollutants into the environment poses serious threats to ecosystems and human health. Currently, various methods are available for TPH-contaminated soil remediation, with bioremediation technology recognized as an environmentally friendly and cost-effective approach. While converting TPH to CO2 is a common remediation method, the complex structures and diverse types of petroleum hydrocarbons (PHs) involved can result in excessive CO2 generation, potentially exacerbating the greenhouse effect. Alternatively, transforming TPH into energy forms like methane through bioremediation, followed by collection and reuse, can reduce greenhouse gas emissions and energy consumption. This process relies on the synergistic interaction between Methanogens archaea and syntrophic bacteria, forming a consortium known as the oil-degrading bacterial consortium. Methanogens produce methane through anaerobic digestion (AD), with hydrogenotrophic methanogens (HTMs) utilizing H2 as an electron donor, playing a crucial role in biomethane production. Candidatus Methanoliparia (Ca. Methanoliparia) was found in the petroleum archaeal community of weathered Oil field in northeast China. Ca. Methanoliparia has demonstrated its independent ability to decompose and produce new energy (biomethane) without symbiosis, contribute to transitioning weathered oil fields towards new energy. Therefore, this review focuses on the principles, mechanisms, and developmental pathways of HTMs during new energy production in the degradation of PHs. It also discusses strategies to enhance TPH degradation and recovery methods.


Asunto(s)
Biodegradación Ambiental , Hidrocarburos , Metano , Petróleo , Contaminantes del Suelo , Petróleo/metabolismo , Hidrocarburos/metabolismo , Contaminantes del Suelo/metabolismo , Metano/metabolismo , Yacimiento de Petróleo y Gas/microbiología , Contaminación por Petróleo , Bacterias/metabolismo
20.
Children (Basel) ; 11(4)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38671703

RESUMEN

This case report sheds light on the management of skeletal deformity in a young child with X-linked hypophosphatemia (XLH), emphasizing the significance of a timely orthotic intervention alongside pharmacological treatment, which is a strategy not frequently highlighted in the XLH literature. The patient, a 2-year-and-7-month-old female, presented with classic XLH symptoms, including short stature, pronounced genu varum, and hypophosphatemia, with deformities observed in both the coronal and sagittal planes of the femur and tibia. Despite initial reliance on pharmacotherapy, which proved insufficient for skeletal realignment, the integration of orthotic treatment at age 3 marked a pivotal turn in the management strategy. By the age of 5 years and 9 months, this combined approach yielded significant improvements: the deformities in the femur and tibia were notably corrected, tibial torsion was addressed, and enhanced limb alignment was achieved, as corroborated by radiographic evidence. This case underscores the effectiveness of orthotic intervention as a critical and underemphasized adjunct to pharmacological therapy in managing XLH in early childhood. It advocates for the early inclusion of orthotic measures to optimize treatment outcomes and expand the range of management strategies for limb deformities.

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