Flavonoids possess diverse bioactivity and potential medicinal values. Glycosylation of flavonoids, coupling flavonoid aglycones and glycosyl groups in conjugated form, can change the biological ...activity of flavonoids, increase water solubility, reduce toxic and side effects, and improve specific targeting. Therefore, it is desirable to synthesize various flavonoid glycosides for further investigation on their medicinal values. Compared with chemical glycosylations, biotransformations catalyzed by uridine diphospho-glycosyltransferases provide an environmentally friendly way to construct glycosidic bonds without repetitive chemical synthetic steps of protection, activation, coupling, and deprotection. In this review, we will summarize the existing knowledge on the biotechnological glycosylation reactions either in vitro or in vivo for the synthesis of flavonoid O- and C-glycosides and other rare analogs.
Key points
• Flavonoid glycosides usually show improved properties compared with their flavonoid aglycones.
• Chemical glycosylation requires repetitive synthetic steps and purifications.
• Biotechnological glycosylation reactions either in vitro or in vivo were discussed.
• Provides representative synthetic examples in detail.
•A synthetic biomimetic SERS sensor for highly specific and sensitive detection of ACP is realized.•Boronate affinity-based surface imprinting approach is applied for specific extraction of trace ...targets.•The approach shows great versatility by imprinting different glycoproteins.
In this paper, we introduce a synthetic biomimetic receptors-based surface enhanced Raman scattering (SERS) sensor for highly specific recognition and detection of acid phosphatase in complex biological samples. It depends on the establishment of molecular imprinted polymers (MIPs) which capture the target glycoprotein via biomimetic recognition, and SERS probes which bind to glycoproteins by boronate affinity. The MIPs layer was synthesized through self-polymerization of dopamine on the surface of glycoprotein-immobilized polymeric skeletons, which was prepared by choosing 4-vinylphenylboronic acid (VPBA) as functional monomers, pentaerythritol triacrylate (PETA) as crosslinker, ethyleneglycol (EG) and cyclohexanol as porogens. The accessible and stable recognition sites allowed the rebinding of the template and offered good reproducibility. The proposed biomimetic recognition-based SERS sensor showed superb performances for acid phosphatase detection with high sensitivity (LOD of 0.1 ng mL−1) and excellent selectivity.
Antibiotics are a category of chemical compounds used to treat bacterial infections and are widely applied in cultivation, animal husbandry, aquaculture, and pharmacy. Currently, residual antibiotics ...and their metabolites pose a potential risk of allergic reactions, bacterial resistance, and increased cancer incidence. Residual antibiotics and the resulting bacterial antibiotic resistance have been recognized as a global challenge that has attracted increasing attention. Therefore, monitoring antibiotics is a critical way to limit the ecological risks from antibiotic pollution. Accordingly, it is desirable to devise new analytical platforms to achieve efficient antibiotic detection with excellent sensitivity and specificity. Quantum dots (QDs) are regarded as an ideal material for use in the development of antibiotic detection biosensors. In this review, we characterize different types of QDs, such as silicon, chalcogenide, carbon, and other doped QDs, and summarize the trends in QD-based antibiotic detection. QD-based sensing applications are classified according to their recognition strategies, including molecularly imprinted polymers (MIPs), aptamers, and immunosensors. We discuss the advantages of QD-derived antibiotic sensors, including low cost, good sensitivity, excellent stability, and fast response, and illustrate the current challenges in this field.
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•The strategies of applying quantum dots (QDs) in antibiotic detection are described.•The QD-based sensors of antibiotics are first summarized.•Sensors are classified according to antibiotic-recognition strategy.•QD antibiotic detection abilities and advantages are described.
Transcription factors (TFs) regulate gene expression by binding to regulatory regions, and their dysregulation is involved in numerous diseases. Thus, they are therapeutic targets and potential ...diagnostic markers. However, widely used methods for TFs detection are either cumbersome or costly. Herein, we first applied DNA-Ag nanoclusters molecular beacons (AgMBs) in TFs analysis and designed an assay based on the switchable fluorescence of AgMBs. In the absence of TFs, a single-stranded DNA functioned as a reporter is released from a double-stranded DNA probe (referred as dsTFs probe) under exonuclease III (Exo III) digestion. Then, the reporter triggers downstream Exo III-assisted signal amplification by continuously consuming the guanine-rich enhancer sequences in AgMBs, resulting in significant fluorescent decrease eventually. Conversely, the presence of TFs protects the dsTFs probe from digestion and blocks the downstream reaction to keep a highly fluorescent state. To testify this rationale, we utilized nuclear factor-kappa B p50 (NF-κB p50) as a model TFs. Owing to the amplification strategy, this method exhibited high sensitivity toward NF-κB p50 with a limit of detection of 10 pM, and a broad linear range from 30 pM to 1.5 nM. Furthermore, this method could detect multiple TFs in human colon cancer DLD-1 cells and reflect the variation in their cellular levels after stimulation. Finally, by conducting an inhibition assay we revealed the potential of this method for screening TFs-targeted drugs and calculating the IC50 of corresponding inhibitors.
Lactic acid, a metabolic by-product of host and intestinal microbiota, has been recovered as an active signal molecule in the immune system. In this study, a lactic acid biosynthesis pathway that ...directly produces lactic acid from glucose rather than ethanol with high production was reconstructed in
. The engineered
showed anti-inflammatory activity in dextran sulfate sodium (DSS)-induced mice with improved histological damage, increased mucosal barrier, and decreased intestinal immune response. Lactic acid regulated the macrophage polarization state and inhibited the expression of pro-inflammatory cytokines
and
. Increasing the macrophage monocarboxylic acid transporter-mediated active lactic acid uptake suppressed the excessive activation of the NLRP3 inflammasome and the downstream caspase-1 pathway in macrophages. Moreover, lactic acid promoted histone H3K9 acetylation and histone H3K18 lactylation. Meanwhile, the engineered
altered the diversity and composition of the intestinal microbiota and changed the abundance of metabolic products in mice with colitis. In conclusion, this study shows that the application of engineered
attenuated DSS-induced colitis in mice
suppressing macrophage pyroptosis and modulating the intestinal microbiota, which is an effective and safe treatment strategy for ulcerative colitis.
Polyethylene terephthalate (PET) biodegradation is regarded as an environmentally friendly degradation method. In this study, an artificial microbial consortium composed of
,
and two metabolically ...engineered
was constructed to degrade PET. First, a two-species microbial consortium was constructed with two engineered
that could secrete PET hydrolase (PETase) and monohydroxyethyl terephthalate hydrolase (MHETase), respectively; it could degrade 13.6% (weight loss) of the PET film within 7 days. A three-species microbial consortium was further obtained by adding
to reduce the inhibition caused by terephthalic acid (TPA), a breakdown product of PET. The weight of PET film was reduced by 31.2% within 3 days, achieving about 17.6% improvement compared with the two-species microbial consortium. Finally,
was introduced to reduce the inhibition caused by ethylene glycol (EG), another breakdown product of PET, obtaining a four-species microbial consortium. With the four-species consortium, the weight loss of PET film reached 23.2% under ambient temperature. This study constructed and evaluated the artificial microbial consortia in PET degradation, which demonstrated the great potential of artificial microbial consortia in the utilization of complex substrates, providing new insights for biodegradation of complex polymers.
1,1,1-Trichloroethane (TCA), labeled as a priority pollutant by the Environmental Protection Agency (EPA) of China, can be removed from groundwater by sonochemical oxidation. The sonochemical ...oxidation of TCA in the presence of persulfate (PS) showed a significant synergistic effect. The operational parameters, ultrasonic frequency, PS/TCA molar ratio, radical scavenger, inorganic anions (Cl−, CO32-, HCO3- and NO3-) and humic acid (HA), were evaluated during the investigation of the sonochemical reaction. The results showed that the degradation of TCA followed pseudo-first-order kinetics, and the rate constant was found to increase with increasing ultrasonic frequency but to decrease with both an increasing PS/TCA molar ratio and an increasing concentration of inorganic anions. With a concentration of 4.46mg/L of HA in solution, an enhanced effect was observed. Further addition of HA retarded the degradation rate of TCA. TCA could be eliminated almost completely by sono-activated persulfate oxidation, with sulfate and hydroxyl radicals serving as the principal oxidants as confirmed by the addition of radical scavengers. Eleven chlorinated degradation intermediates were detected and quantified by purge and trap gas chromatography coupled with mass spectrometry (P&T-GC–MS) in the absence of pH buffer. Three TCA degradation pathways were therefore proposed. In conclusion, the sono-activated persulfate oxidation process appears to be a highly promising technique for the remediation of TCA-contaminated groundwater.
Poly(ethylene terephthalate) hydrolase (PETase) from Ideonella sakaiensis exhibits a strong ability to degrade poly(ethylene terephthalate) (PET) at room temperature, and is thus regarded as a ...potential tool to solve the issue of polyester plastic pollution. Therefore, we explored the interaction between PETase and the substrate (a dimer of the PET monomer ethylene terephthalate, 2PET), using a model of PETase and its substrate. In this study, we focused on six key residues around the substrate-binding groove in order to create novel high-efficiency PETase mutants through protein engineering. These PETase mutants were designed and tested. The enzymatic activities of the R61A, L88F, and I179F mutants, which were obtained with a rapid cell-free screening system, exhibited 1.4 fold, 2.1 fold, and 2.5 fold increases, respectively, in comparison with wild-type PETase. The I179F mutant showed the highest activity, with the degradation rate of a PET film reaching 22.5 mg per μmol·L−1 PETase per day. Thus, this study has created enhanced artificial PETase enzymes through the rational protein engineering of key hydrophobic sites, and has further illustrated the potential of biodegradable plastics.
Here, we report the successful design, construction, and characterization of a 770-kilobase synthetic yeast chromosome II (synII). Our study incorporates characterization at multiple levels-including ...phenomics, transcriptomics, proteomics, chromosome segregation, and replication analysis-to provide a thorough and comprehensive analysis of a synthetic chromosome. Our Trans-Omics analyses reveal a modest but potentially relevant pervasive up-regulation of translational machinery observed in synII, mainly caused by the deletion of 13 transfer RNAs. By both complementation assays and SCRaMbLE (synthetic chromosome rearrangement and modification by
-mediated evolution), we targeted and debugged the origin of a growth defect at 37°C in glycerol medium, which is related to misregulation of the high-osmolarity glycerol response. Despite the subtle differences, the synII strain shows highly consistent biological processes comparable to the native strain.
The intramuscular fat (or marbling fat) content is an essential economic trait of beef cattle and improves the flavor and palatability of meat. Several studies have highlighted the correlation ...between long non-coding RNAs (lncRNAs) and intramuscular fat development; however, the precise molecular mechanism remains unknown. Previously, through a high-throughput sequencing analysis, we found a lncRNA and named it a long non-coding RNA BNIP3 (lncBNIP3). The 5' RACE and 3' RACE explored 1945 bp total length of lncBNIP3, including 1621 bp of 5'RACE, and 464 bp of 3'RACE. The nucleoplasmic separation and FISH results explored the nuclear localization of lncBNIP3. Moreover, the tissue expression of lncBNIP3 was higher in the longissimus dorsi muscle, followed by intramuscular fat. Furthermore, down-regulation of lncBNIP3 increased the 5-Ethynyl-2'- deoxyuridine (EdU)-EdU-positive cells. The flow cytometry results showed that the number of cells in the S phase was significantly higher in preadipocytes transfected with si-lncBNIP3 than in the control group (si-NC). Similarly, CCK8 results showed that the number of cells after transfection of si-lncBNIP3 was significantly higher than in the control group. In addition, the mRNA expressions of proliferative marker genes CyclinB1 (CCNB1) and Proliferating Cell Nuclear Antigen (PCNA) in the si-lncBNIP3 group were significantly higher than in the control group. The Western Blot (WB) results also showed that the protein expression level of PCNA transfection of si-lncBNIP3 was significantly higher than in the control group. Similarly, the enrichment of lncBNIP3 significantly decreased the EdU-positive cells in the bovine preadipocytes. The results of flow cytometry and CCK8 assay also showed that overexpression of lncBNIP3 inhibited the proliferation of bovine preadipocytes. In addition, the overexpression of lncBNIP3 significantly inhibited the mRNA expressions of CCNB1 and PCNA. The WB results showed that the overexpression of lncBNIP3 significantly inhibited the expression of the CCNB1 protein level. To further explore the mechanism of lncBNIP3 on the proliferation of intramuscular preadipocytes, RNA-seq was performed after interference with si-lncBNIP3, and 660 differentially expressed genes (DEGs) were found, including 417 up-regulated DEGs and 243 down-regulated DEGs. The KEGG pathway analysis showed that the cell cycle was the most significant pathway for the functional enrichment of DEGs, followed by the DNA replication pathway. The RT-qPCR quantified the expression of twenty DEGs in the cell cycle. Therefore, we speculated that lncBNIP3 regulated intramuscular preadipocyte proliferation through the cell cycle and DNA replication pathways. To further confirm this hypothesis, the cell cycle inhibitor Ara-C was used to inhibit DNA replication of the S phase in intramuscular preadipocytes. Herein, Ara-C and si-lncBNIP3 were simultaneously added to the preadipocytes, and the CCK8, flow cytometry, and EdU assays were performed. The results showed that the si-lncBNIP3 could rescue the inhibitory effect of Ara-C in the bovine preadipocyte proliferation. In addition, lncBNIP3 could bind to the promoter of cell division control protein 6 (CDC6), and down-regulation of lncBNIP3 promoted the transcription activity and the expression of CDC6. Therefore, the inhibitory effect of lncBNIP3 on cell proliferation might be understood through the cell cycle pathway and CDC6 expression. This study provided a valuable lncRNA with functional roles in intramuscular fat accumulation and revealed new strategies for improving beef quality.
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