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The discovery and application of genome editing introduced a new era of plant breeding by giving researchers efficient tools for the precise engineering of crop genomes1. Here we demonstrate the power of genome editing for engineering broad-spectrum disease resistance in rice (Oryza sativa). We first isolated a lesion mimic mutant (LMM) from a mutagenized rice population. We then demonstrated that a 29-base-pair deletion in a gene we named RESISTANCE TO BLAST1 (RBL1) caused broad-spectrum disease resistance and showed that this mutation caused an approximately 20-fold reduction in yield. RBL1 encodes a cytidine diphosphate diacylglycerol synthase that is required for phospholipid biosynthesis2. Mutation of RBL1 results in reduced levels of phosphatidylinositol and its derivative phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). In rice, PtdIns(4,5)P2 is enriched in cellular structures that are specifically associated with effector secretion and fungal infection, suggesting that it has a role as a disease-susceptibility factor3. By using targeted genome editing, we obtained an allele of RBL1, named RBL1Δ12, which confers broad-spectrum disease resistance but does not decrease yield in a model rice variety, as assessed in small-scale field trials. Our study has demonstrated the benefits of editing an LMM gene, a strategy relevant to diverse LMM genes and crops.
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Diacilglicerol Colinofosfotransferase , Resistência à Doença , Edição de Genes , Oryza , Melhoramento Vegetal , Doenças das Plantas , Resistência à Doença/genética , Edição de Genes/métodos , Genoma de Planta/genética , Oryza/enzimologia , Oryza/genética , Oryza/microbiologia , Fosfatidilinositóis/metabolismo , Melhoramento Vegetal/métodos , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Alelos , Fosfatidilinositol 4,5-Difosfato/metabolismo , Diacilglicerol Colinofosfotransferase/genética , Diacilglicerol Colinofosfotransferase/metabolismoRESUMO
We determined the genetic association between specific human leucocyte antigen (HLA) loci and autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy. Our results showed that autoimmune GFAP astrocytopathy was associated with HLA-A*3303 (odds ratio [OR] = 2.02, 95% confidence interval [CI] = 1.32-3.06, p = 0.00072, padj. = 0.046) and HLA-DBP1*0501 (OR = 0.51, 95% CI = 0.36-0.71, p = 0.000048, padj. = 0.0062). Moreover, HLA-A*3303 carriers with the disease had a longer hospital stay (p = 0.0005) than non-carriers. This study for the first time provides evidence for a role of genetic factor in the development of autoimmune GFAP astrocytopathy. ANN NEUROL 2024;95:901-906.
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Astrócitos , Proteína Glial Fibrilar Ácida , Antígenos HLA-A , Cadeias beta de HLA-DP , Humanos , Proteína Glial Fibrilar Ácida/genética , Masculino , Feminino , Pessoa de Meia-Idade , Cadeias beta de HLA-DP/genética , Adulto , Antígenos HLA-A/genética , Astrócitos/metabolismo , Astrócitos/patologia , IdosoRESUMO
The indica rice variety Huizhan shows elite traits of disease resistance and heat tolerance. However, the underlying genetic basis of these traits is not fully understood due to limited genomic resources. Here, we used Nanopore long-read and next-generation sequencing technologies to generate a chromosome-scale genome assembly of Huizhan. Comparative genomics analysis uncovered a large chromosomal inversion and expanded gene families that are associated with plant growth, development and stress responses. Functional rice blast resistance genes, including Pi2, Pib and Ptr, and bacterial blight resistance gene Xa27, contribute to disease resistance of Huizhan. Furthermore, integrated genomics and transcriptomics analyses showed that OsHIRP1, OsbZIP60, the SOD gene family, and various transcription factors are involved in heat tolerance of Huizhan. The high-quality genome assembly and comparative genomics results presented in this study facilitate the use of Huizhan as an elite parental line in developing rice varieties adapted to disease pressure and climate challenges.
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Resistência à Doença , Oryza , Termotolerância , Oryza/genética , Resistência à Doença/genética , Termotolerância/genética , Transcriptoma , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Genoma de Planta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , GenômicaRESUMO
BACKGROUND: Rice ECQ (eating and cooking quality) is an important determinant of rice consumption and market expansion. Therefore, improvement of ECQ is one of the primary goals in rice breeding. However, ECQ-related quantitative trait loci (QTL) have not yet been fully revealed. The present study aimed to identify a major effect QTL for rice taste, an important component of ECQ via genotyping-by-sequencing, to reveal the associated molecular mechanisms, and to predict key candidate genes. RESULTS: A population of F9 recombinant inbred lines resulting from a cross between R668 (national standard of high-quality third class) and R838 (common edible rice) was used to construct a high-density genetic map (2,295.062 cM). The map comprises 639,504 markers distributed on 12 linkage elements with an average genetic distance of 0.004 cM. We detected a major taste-related QTL, qECQ8, which explained 41.4% of phenotypic variance and had LOD values of 4.42-7.73. Using a five-generation NIL population from the backcross of "Ganxiangzhan No. 1" carrying qECQ8 with the recurrent parent R838 (without qECQ8), we narrowed qECQ8 to a 187.5 kb interval between markers M33 and M37 on Chr8. Comparative transcriptomic analysis revealed that photosynthesis, glyoxylate and dicarboxylate metabolism, carbon fixation in photosynthetic organisms, and alpha-linolenic acid metabolism were induced in developing seeds of lines containing qECQ8. Furthermore, we identified two candidate genes in the qECQ8 region, including LOC_Os08g30550 (zinc knuckle family protein), a major candidate for genetic-assisted breeding of high-quality rice. CONCLUSION: Our findings provide important genetic resources for targeted improvement of rice taste quality and may facilitate the genetic breeding of rice ECQ.
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Mapeamento Cromossômico , Oryza , Locos de Características Quantitativas , Paladar , Oryza/genética , Locos de Características Quantitativas/genética , Paladar/genética , Fenótipo , Cromossomos de Plantas/genéticaRESUMO
Fibrillated cellulose-based nanocomposites can improve energy efficiency of building envelopes, especially windows, but efficiently engineering them with a flexible ability of lighting and thermal management remains highly challenging. Herein, a scalable interfacial engineering strategy is developed to fabricate haze-tunable thermal barrier films tailored with phosphorylated cellulose nanofibrils (PCNFs). Clear films with an extremely low haze of 1.6% (glass-scale) are obtained by heat-assisted surface void packing without hydrophobization of nanocellulose. PCNF gel cakes serve here as templates for surface roughening, thereby resulting in a high haze (73.8%), and the roughened films can block heat transfer by increasing solar reflection in addition to a reduced thermal conduction. Additionally, obtained films can tune distribution of light from visible to near-infrared spectral range, enabling uniform colored lighting and inhibiting localized heating. Furthermore, an integrated simulation of lighting and cooling energy consumption in the case of office buildings shows that the film can reduce the total energy use by 19.2-38.1% under reduced lighting levels. Such a scalable and versatile engineering strategy provides an opportunity to endow nanocellulose-reinforced materials with tunable optical and thermal functionalities, moving their practical applications in green buildings forward.
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Antigen presentation by HLA class II molecules to CD4+ T cells is an essential step for generating antibodies to hepatitis B antigens. In this study, we investigated the association between the HLA-DRB1 gene and the status of antibodies to hepatitis B surface and e antigens. Our results revealed a significant association between the status of anti-HBsAg and HLA-DRB1*04:03 (OR = 4.11, 95% CI = 1.50-10.84, p = 0.005, Padj. = 0.05) as well as HLA-DRB1*15:01 (OR = 1.74, 95% CI = 1.20-2.50, p = 0.002, Padj. = 0.045). MHC II binding predictions and in silico docking demonstrated strong binding affinity of HBsAg peptides to these two HLA-DRB1 molecules. Conversely, the status of anti-HBeAg was inversely associated with HLA-DRB1*14:54 (OR = 0.34, 95% CI = 0.18-0.64, p = 0.001, Padj. = 0.011), and in silico analysis revealed weak binding affinity of HBeAg peptides to HLA-DRB1*14:54. In conclusion, these findings support the involvement of HLA-DRB1 in humoral immunity against HBV infection.
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Alelos , Cadeias HLA-DRB1 , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Humanos , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/genética , Masculino , Feminino , Adulto , Anticorpos Anti-Hepatite B/imunologia , Anticorpos Anti-Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Antígenos E da Hepatite B/genética , Pessoa de Meia-Idade , Hepatite B/imunologia , Hepatite B/virologia , Adulto Jovem , Ligação Proteica , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/genética , Simulação de Acoplamento MolecularRESUMO
Meeting the ever-increasing food demands of a growing global population while ensuring resource and environmental sustainability presents significant challenges for agriculture worldwide. Arbuscular mycorrhizal symbiosis (AMS) has emerged as a potential solution by increasing the surface area of a plant's root system and enhancing the absorption of phosphorus, nitrogen nutrients, and water. Consequently, there is a longstanding hypothesis that rice varieties exhibiting more efficient AMS could yield higher outputs at reduced input costs, paving the way for the development of Green Super Rice (GSR). Our prior research study identified a variant, OsCERK1DY, derived from Dongxiang wild-type rice, which notably enhanced AMS efficiency in the rice cultivar "ZZ35." This variant represents a promising gene for enhancing yield and nutrient use efficiency in rice breeding. In this study, we conducted a comparative analysis of biomass, crop growth characteristics, yield attributes, and nutrient absorption at varying soil nitrogen levels in the rice cultivar "ZZ35" and its chromosome single-segment substitution line, "GJDN1." In the field, GJDN1 exhibited a higher AM colonization level in its roots compared with ZZ35. Notably, GJDN1 displayed significantly higher effective panicle numbers and seed-setting rates than ZZ35. Moreover, the yield of GJDN1 with 75% nitrogen was 14.27% greater than the maximum yield achieved using ZZ35. At equivalent nitrogen levels, GJDN1 consistently outperformed ZZ35 in chlorophyll (Chl) content, dry matter accumulation, major nutrient element accumulation, N agronomic efficiency (NAE), N recovery efficiency (NRE), and N partial factor productivity (NPFP). The performance of OsCERK1DY overexpression lines corroborated these findings. These results support a model wherein the heightened level of AMS mediated by OsCERK1DY contributes to increased nitrogen, phosphorus, and potassium accumulation. This enhancement in nutrient utilization promotes higher fertilizer efficiency, dry matter accumulation, and ultimately, rice yield. Consequently, the OsCERK1DY gene emerges as a robust candidate for improving yield, reducing fertilizer usage, and facilitating a transition towards greener, lower-carbon agriculture. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01459-8.
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Antibiotic residues have become a worldwide public safety issue. It is vital to detect multiple antibiotics simultaneously using sensors. A new and efficient method is proposed for the combined detection of two antibiotics (enrofloxacin (Enro) and ciprofloxacin (Cip)) in milk using surface plasmon resonance (SPR) sensors. Based on the principle of immunosuppression, two antibiotic antigens (for Enro and Cip) were immobilized on an optical fiber surface with conjugates of bovine serum albumin using dopamine (DA) polymerization. Each single antigen was bound to its corresponding antibody to derive standard curves for Enro and Cip. The fiber-optic sensor's sensitivity was 2900 nm/RIU. Detection limits were calculated to be 1.20 ng/mL for Enro and 0.81 ng/mL for Cip. The actual system's recovery rate was obtained by testing Enro and Cip in milk samples; enrofloxacin's and ciprofloxacin's mean recoveries from the milk samples were 96.46-120.46% and 96.74-126.9%, respectively. In addition, several different regeneration solutions were tested to analyze the two target analytes' regeneration ability; NaOH and Gly-HCl solutions were found to have the best regeneration ability.
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Antibacterianos , Ressonância de Plasmônio de Superfície , Enrofloxacina , Ciprofloxacina , Tecnologia de Fibra ÓpticaRESUMO
INTRODUCTION: The α-globin fusion gene between the HBA2 and HBAP1 genes becomes clinically important in thalassemia screening because this fusion gene can cause severe hemoglobin (Hb) H disease when combining with α0 -thalassemia (α0 -thal). Due to its uncommon rearrangement in the α gene cluster without dosage changes, this fusion gene is undetectable by common molecular testing approaches used for α-thal diagnosis. METHODS: In this study, we used the single-molecule real-time (SMRT) sequencing technique to detect this fusion gene in 23 carriers identified by next-generation sequencing (NGS) among 16,504 screened individuals. Five primers for α and ß thalassemia were utilized. RESULTS: According to the NGS results, the 23 carriers include 14 pure heterozygotes, eight compound heterozygotes with common α-thal alleles, and one homozygote. By using SMRT, the fusion mutant was successfully detected in all 23 carriers. Furthermore, SMRT corrected the diagnosis in two "pure" heterozygotes: one was compound heterozygote with anti-3.7 triplication, and the other was homozygote. CONCLUSION: Our results indicate that SMRT is a superior method compared to NGS in detecting the α fusion gene, attributing to its efficient, accurate, and one-step properties.
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Talassemia alfa , Talassemia beta , Humanos , alfa-Globinas/genética , Heterozigoto , Homozigoto , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Talassemia alfa/epidemiologia , Talassemia beta/diagnóstico , Talassemia beta/genética , Talassemia beta/epidemiologiaRESUMO
With increasing awareness about the ecological environment, increased attention has been paid to the application of eco-friendly materials in the field of marine antifouling. In this work, a novel coating having good mechanical strength and static marine antifouling characteristics was fabricated using cellulose nanocrystals (CNCs) as the skeleton material, with in situ growth of SiO2 as the basic superhydrophobic material and introducing hexadecyl trimethyl ammonium bromide (CTAB) and 4-bromo2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile (Econea) into the coating. Due to the high strength and rod structure of CNCs, the coating maintained super-hydrophobicity after 50 cycles of abrasion tests. Moreover, the addition of CTAB during the synthesis of SiO2 led to the hydrolysis and polycondensation of tetraethyl orthosilicate at the micellar interface. Econea was fully mixed with SiO2 nanoparticles, thus slowing down the rate of release of Econea. Meanwhile, the adhesion between the coating and the substrate reached 1.9 MPa, which can meet the application requirements for marine environments. The bioassay using bacteria (Escherichia coli) and diatoms (Nitzschia closterium) showed that the rate of inhibition of the coating on bacteria and diatoms could reach 99 and 90%, respectively, after immersion in artificial seawater for 28 days. This research provides a facile and promising fabricating solution of an eco-friendly CNC-based coating having strong antifouling characteristics suitable for marine environments.
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Incrustação Biológica , Diatomáceas , Desinfetantes , Nanopartículas , Celulose/química , Incrustação Biológica/prevenção & controle , Cetrimônio , Dióxido de Silício , Nanopartículas/químicaRESUMO
Cellulose nanocrystals (CNC) are recognized as promising bio-based flocculants for controlling harmful algal blooms (HABs). Due to the charge shielding effect in seawater and the strong mobility of algae cells, CNC can't effectively remove Phaeocystis globosa from seawater. To solve this problem, peroxymonosulfate (PMS) was used to enhance the coagulation of CNC for rapidly removal of P. globosa. The results showed that 91.7% of Chl-a, 95.2% of OD680, and 97.2% of turbidity of P. globosa were reduced within 3 h with the use of 200 mg L-1 of CNC and 20 mg L-1 of PMS. The removal of P. globosa was consisted of inactivation and flocculation. Notably, electron paramagnetic resonance (EPR) spectrums and quenching experiments revealed that the inactivation of P. globosa was dominated by PMS oxidation and 1O2. Subsequently, CNC entrained inactivated algal cells to settle to the bottom to achieve efficient removal of P. globosa. The content of total organic carbon (TOC) and chemical oxygen demand (COD) decreased significantly, indicating that a low emission risk of algal cell effluent was produced in the CNC-PMS system. In view of the excellent performance on P. globosa removal, we believe that the CNC-PMS system has great potential for HABs treatments.
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Thanks to the advantages of low disturbance, good concealment and high mobility, bionic fishes have been developed by many countries as equipment for underwater observation and data collection. However, differentiating between true and bionic fishes has become a challenging task. Commonly used acoustic and optical technologies have difficulty in differentiating bionic fishes from real ones due to their high similarity in shape, size, and camouflage ability. To solve this problem, this paper proposes a novel idea for bionic fish recognition based on blue-green light reflection, which is a powerful observation technique for underwater object detection. Blue-green light has good penetration under water and thus can be used as a signal carrier to recognize bionic fishes of different surface materials. Three types of surface materials representing bionic fishes, namely titanium alloy, carbon fiber, and nylon, are investigated in this paper. We collected 1620 groups of blue-green light reflection data of these three kinds of materials and for two real fishes. Following this, three machine learning algorithms were utilized for recognition among them. The recognition accuracy can reach up to about 92.22%, which demonstrates the satisfactory performance of our method. To the best of our knowledge, this is the first work to investigate bionic fish recognition from the perspective of surface material difference using blue-green light reflection.
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Biônica , Peixes , Animais , Visão OcularRESUMO
In nature, symbiosis with arbuscular mycorrhizal (AM) fungi contributes to sustainable acquisition of phosphorus and other elements in over 80% of plant species; improving interactions with AM symbionts may mitigate some of the environmental problems associated with fertilizer application in grain crops such as rice. Recent developments of high-throughput genome sequencing projects of thousands of rice cultivars and the discovery of the molecular mechanisms underlying AM symbiosis suggest that interactions with AM fungi might have been an overlooked critical trait in rice domestication and breeding. In this review, we discuss genetic variation in the ability of rice to form AM symbioses and how this might have affected rice domestication. Finally, we discuss potential applications of AM symbiosis in rice breeding for more sustainable agriculture.
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Micorrizas , Oryza , Oryza/genética , Oryza/microbiologia , Simbiose/genética , Domesticação , Fertilizantes , Melhoramento Vegetal , Micorrizas/genética , Produtos Agrícolas/genética , Produtos Agrícolas/microbiologia , Fósforo , Raízes de Plantas/microbiologiaRESUMO
Rice domestication has dramatically improved its agronomic traits, albeit with unavoidable significantly reduced genetic diversity. Dongxiang common wild rice, the wild rice species distributed in northernmost China, exhibits excellent resistance against stress and diseases and provides a rich genetic resource for rice breeding. Most of the studies focus on the function of the plant genes, often disregarding the role of the root microbes associated with the plants. In this work, we isolated a Burkholderia strain from the root of Dongxiang wild rice, which we identified as Burkholderia cepacia BRDJ, based on a phylogenetic analysis. This strain promoted the rice growth under greenhouse conditions. The grain yield was higher in a rice line containing a small genomic fragment derived from the Dongxiang wild rice, compared to the indica rice cultivar Zhongzao 35. This new strain also increased the plant biomass under limiting nitrogen conditions. Interestingly, this strain had a differential effect on indica and japonica rice varieties under full nitrogen supply conditions. By genome sequencing and comparison with another two B. cepacia strains, we observed enriched genes related with nitrogen fixation and phytohormone and volatiles biosynthesis that may account for the growth-promoting effects of the BRDJ. BRDJ has the potential to be used as a biofertilizer in promoting nitrogen use efficiency and overall growth in rice.
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Oryza , Nitrogênio , Oryza/genética , Filogenia , Melhoramento Vegetal , Reguladores de Crescimento de PlantasRESUMO
Osteoarthritis is a prevalent degenerative joint disease characterized by progressive articular cartilage loss and destruction. The resultant increase in friction causes severe pain. The collagen I matrix (COL I) has been used clinically for cartilage repair; however, how COL I acts at cartilage surfaces is unclear. Here, we studied adsorption and lubrication of synovial fluid components, albumin, γ-globulin, and the phospholipid DPPC, on COL I under physiological conditions using surface plasmon resonance and an in situ sensing surface force apparatus. Our results revealed COL I had poor lubrication ability, a fairly high coefficient of friction (COF, µ = 0.651 ± 0.013), and surface damage under a 7 mN load. DPPC formed an improved lubricating layer on COL I (µ = 0.072 ± 0.016). In sharp contrast, albumin and γ-globulin exhibited poor lubrication with an order of magnitude higher COF but still provided benefits by protecting COL I from wear. Hence, DPPC on COL I may help optimize COL I implantation design.
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Cartilagem Articular , Colágeno Tipo I , Fricção , Lipídeos , LubrificaçãoRESUMO
Nanoplastics (NPs) are becoming an emerging pollutant of global concern. A potential risk of NPs is that they can serve as carriers and synergistically function with other contaminants to cause diseases. A variety of diseases such as Alzheimer's disease are related to the generation of amyloid fibrils, and insulin is typically used as a model to study the fibrillation process. In this study, we examined the fibrillation of insulin promoted by polystyrene nanoplastics (PSNPs) alone and synergistically with organic contaminants (denoted as X, X = pyrene, bisphenol A, 2,2',4,4'-tetrabromodiphenyl ether, 4,4'-dihydroxydiphenylmethane, or 4-nonylphenol) having different polarities using thioflavin T fluorescence assays, dynamic light scattering, and circular dichroism spectroscopy. The presence of PSNPs and small organic contaminants decreased the lag phase time (tlag) for insulin fibrillation from 54.6 h to 35-51 h and their combination (PS-X) enhanced this process (tlag = 21-30 h). Notably, the lag phase time for insulin fibrillation with PS-nonpolar contaminants, PS-weakly polar contaminants, and PS-polar contaminants is around 20.8, 26.7, and 30.1 h, respectively, indicating the synergistic effect of PS-nonpolar contaminants or PS-weakly polar contaminants was more obvious than that of PS-polar contaminants. Moreover, molecular dynamic simulation reveal the interactions between insulin and PSs or small organic contaminants are primarily driven by van der Waals forces and hydrophobic interactions. Overall, the findings of this study underscore the potentially significant environmental impact of small organic contaminants assisting NPs in promoting insulin fibrillation.
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Poluentes Ambientais/química , Insulina/química , Microplásticos/química , Nanopartículas/química , Poliestirenos/química , Compostos Benzidrílicos/química , Éteres Difenil Halogenados/química , Fenóis/química , Pirenos/químicaRESUMO
The symbiotic interaction between arbuscular mycorrhizal fungi (AMF) and land plants is essential for efficient nutrient acquisition and utilisation. Our understanding of key processes controlling the AMF colonisation in rice is still limited. Dongxiang wild rice (DY) exhibited a stronger colonisation with Rhizophagus irregularis than the rice cultivar Zhongzao 35 (ZZ35). Chromosome segment substitution lines were constructed and the OsCERK1 gene from DY was mapped. Transgenic plants in the japonica rice Zhonghua 11 (ZZ11) were constructed to compare root colonisation by AMF. Chromosome single-segment substitution lines containing OsCERK1DY showed higher phosphorus content and grain yield relative to ZZ35. Four amino acids substitutions were identified among the OsCERK1 haplotypes of DY, ZZ35 and ZH11 and two of these were in the second lysine-motif domain, which is essential for the differences of AMF colonisation level among rice varieties. Heterologous expression of OsCERK1DY in ZH11 significantly enhanced AMF colonisation and increased resistance against the pathogenic fungi Magnaporthe oryzae. Notably, the OsCERK1DY haplotype was absent from 4660 cultivated rice varieties. We conclude that OsCERK1 is a key gene affecting the symbiotic interaction with AMF and OsCERK1DY has the biotechnological potential to increase rice phosphorus acquisition and utilisation efficiency for sustainable agriculture.
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Micorrizas/fisiologia , Oryza/metabolismo , Oryza/microbiologia , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Variação Genética , Humanos , Oryza/genética , Proteínas de Plantas/genética , Raízes de Plantas/microbiologia , SimbioseRESUMO
A superhydrophobic and superoleophilic porous composite was successfully prepared via a polydopamine-assisted surface coating of MIL-53(Fe) and 1-dodecanethiol (DDT) on a melamine formaldehyde (MF) sponge. The as-prepared sponge composite (MIL-DDT@MF) has a high water contact angle (WCA) of 151.8°, which is probably attributed to both the rough surface derived from in situ growth of MIL-53 nanocrystals and the low surface energy due to grafting of hydrophobic 1-dodecanethiol. The MIL-DDT@MF sponge can effectively absorb oil or organic solvent with an absorption capacity of up to 54.1 (for petroleum) to 120.2 (for chloroform) times its own weight. In addition, the MIL-DDT@MF sponge retained a high absorption capacity and maintained approximately 78% of its original value after 50 cycles of reuse. Moreover, the MIL-DDT@MF sponge can selectively absorb the oil/organic solvent from water and achieve continuous oil-water separation. The separation efficiency of n-hexane, dichloromethane, and crude oil from water or seawater can reach above 95%. The superhydrophobic and superoleophilic MIL-DDT@MF sponge has potential as a promising absorbent for treatment of oily wastewater.
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A convenient and efficient approach for the surface modification of antifouling materials is highly desirable in numerous applications like affinity-based biosensors. Herein, we fabricated a hybrid antifouling coating on Au surfaces, with thiolated hyaluronic acid (HA) being chemically adsorbed to Au surfaces by the "graft to" approach, followed by a self-assembly of a smaller zwitterionic peptide named p-EK to obtain HA/p-EK-modified surfaces. The real-time sensorgrams of surface plasmon resonance biosensor manifested the successful modification of HA and p-EK on Au surfaces, indicating that there were some bare Au substrates on the HA-modified surfaces for peptide binding. The obtained HA/p-EK surfaces exhibited high hydrophilicity with a water contact angle of 9°. Quartz crystal microbalance and surface plasmon resonance experiments verified that further grafting the zwitterionic p-EK peptide on HA-modified surfaces could enhance the antifouling performance by one time. The improved protein resistance could be mainly contributed by the modification of the zwitterionic peptide that shields the exposed Au substrates from interacting with protein foulings. This strategy by grafting a smaller zwitterionic peptide might provide a novel way to achieve an enhanced protein-resistant performance of the macromolecular coating obtained by the "graft to" surface modification approach.
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Ácido Hialurônico , Proteínas , Peptídeos , Técnicas de Microbalança de Cristal de Quartzo , Propriedades de SuperfícieRESUMO
Expansin has nonhydrolytic disruptive activity and synergistically acts with cellulases to enhance the hydrolysis of cellulose. The adsorption-desorption of expansin on noncellulosic lignin can greatly affect the action of expansin on lignocellulose. In this study, three lignins with different sources (kraft lignin (KL), sodium lignin sulfonate (SLS), and enzymatic hydrolysis lignin (EHL)) were selected as the substrates. The real-time adsorption-desorption of Bacillus subtilis expansin (BsEXLX1) on lignins was monitored using quartz crystal microgravimetry with dissipation (QCM-D). The effects of temperature and Tween 80 on the adsorption-desorption behaviors were also investigated. The results show that BsEXLX1 exhibited high binding ability on lignin and achieved maximum adsorption of 283.2, 273.8, and 266.9 ng cm-2 at 25 °C on KL, SLS, and EHL, respectively. The maximum adsorption decreased to 148.2-192.8 ng cm-2 when the temperature increased from 25 to 45 °C. Moreover, Tween 80 competitively bound to lignin and significantly prevented expansin adsorption. After irreversible adsorption of Tween 80, the maximum adsorption of BsEXLX1 greatly decreased to 33.3, 37.2, and 10.3 ng cm-2 at 25 °C on KL, SLS, and EHL, respectively. Finally, a kinetic model was developed to analyze the adsorption-desorption process of BsEXLX1. BsEXLX1 has a higher adsorption rate constant (kA) and a lower desorption rate constant (kD) on KL than on SLS and EHL. The findings of this study provide useful insights into the adsorption-desorption of expansin on lignin.