MACROMOLECULES
·
2025
·
IF 5.2
Shangzhong Zhang,Yixuan Xu,Panpan Li,Minghui Fan,Dejia Chen,Chengming Wang,Lifeng Yan
Polymerization of CO2 into polyurea under mild pressure and temperature is still a challenge, especially when using diamine from natural feedstocks. Herein, l-lysine is directly used as a diamine without derivatization and protection for capture and copolymerization of CO2 under mild temperatures and pressures (0.1–0.5 MPa, 60–90 °C) with the assistance of superbase 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Water-soluble lysine-polyurea (L-PU) has been synthesized. The weight-average molecular weight of L-PU reaches 3 × 104 g/mol, indicating the efficient reaction of lysine and CO2. In addition, NMR studies confirmed that the unprotected carboxyl acid group (−COOH) in L-PU remains more than 80%, and the polymer may be a candidate to replace nonbiodegradable polyacrylate acid (PAA). The free carboxyl acid group also provides a change to further derivatives of the L-PU. Interestingly, the water-soluble L-PU showed efficient fluorescence performance with quantum yield (QY) up to 20%, which may be attributed to the nonconventional intrinsic fluorescence of nonconjugated aliphatic polyureas containing heteroatoms. It allows the L-PU to be used for cell bioimaging, and in vitro studies reveal that the L-PU is biocompatible and can be efficiently endocytosed by cells with bioimaging ability, indicating that it may be a potential drug delivery system for imaging-guided treatment for cancer tissue.
✓ 已验证
产品关联
DOI
高影响因子
Communications Biology
·
2026
·
IF 5.8
Wang Yan,Zhu Yanping,Liu Ning-Hua,Zhao Fang,Cao Hai-Yan,Chen Yin,Zhang Yu-Zhong,Chen Xiu-Lan,Zhang Yu-Qiang,Gao Chao
Free trans -4-hydroxy-L-proline (T4LHyp), primarily released during the natural degradation of collagen, is absorbed and catabolised by heterotrophic bacteria, contributing to the global recycling of carbon and nitrogen. While bacterial T4LHyp catabolism is well documented, our understanding on how bacteria recognize and import T4LHyp remains limited. Here we show that HatA, the substrate binding protein (SBP) of an ATP-binding cassette transporter within the T4LHyp gene cluster of Vibrio alginolyticus 1A11092, recognizes T4LHyp during its uptake by the strain. HatA possessed significant binding affinity towards T4LHyp and L-proline and a binding signature (W 33 F 37 D 86 V 135 F 240 R 243 Y 265 N 267 Y 303 ), acting as the structural determinant for the specific ligand recognition, was defined. This signature is strictly conserved among HatA and its homologs, representing a subgroup of cluster D-II of SBPs. Genes encoding HatA-like SBPs are often located adjacent to collagenase and T4LHyp catabolic enzyme genes, and are nearly exclusively found in the genomes of Vibrio spp. in hosts and marine environments, which helps them exert pathogenicity when encountering host or environmental collagen. This study reveals a T4LHyp SBP in cosmopolitan Vibrio spp., offering better insights into the global T4LHyp catabolism and recycling driven by bacteria.
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 22
·2911
·
IF 5.3
Siyu Zhang,Bing Zhao,Xuejiao Zhang,Fengchang Wu,Qing Zhao
Due to activities like mining and smelting, lead (Pb) enters the atmosphere in various forms in coarse and fine particles. It enters plants mainly through leaves, and goes up the food chain. In this study, PbXn(nano-PbS, mic-PbO and PbCl2) was applied to eggplant (Solanum melongenaL.) leaves, and 379 differential metabolites were identified and analyzed in eggplant leaves using liquid chromatography–mass spectrometry. Multivariate statistical analysis revealed that all three Pb treatments significantly altered the metabolite profile. Compared with nano-PbS, mic-PbO and PbCl2induced more identical metabolite changes. However, the alterations in metabolites related to the TCA cycle and pyrimidine metabolism, such as succinic acid, citric acid and cytidine, were specific to PbCl2. The number of differential metabolites induced by mic-PbO and PbCl2was three times that of nano-PbS, even though the amount of nano-PbS absorbed by leaves was ten times that of PbO and seven times that of PbCl2. This suggests that the metabolic response of eggplant leaves to Pb is influenced by both concentration and form. This study enhances the current understanding of plants’ metabolic response to Pb, and demonstrates that the metabolomics map provides a more comprehensive view of a plant’s response to specific metals.Keywords:metabolite;absorption;metabolic pathway;amino acid;antioxidation
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2021
·
IF 9.147
Wei Tang,Dan Liu,Yu Li,Ming-Yue Zou,Yu-Chen Shao,Jun-Yi Yin,Shao-Ping Nie
The water-extracted polysaccharide from Portulaca oleracea L. mainly consisted of two pectic polysaccharides designated as POWP-H and POWP-L. The POWP-L was rich in linear homogalacturonan with GalA content of 77.6%, while POWP-H might be a rhamnogalacturonan I (RG-I) pectin composed of Rha (15.7%), Ara (31.7%), Gal (42.5%) and GalA (10.1%). The structure of POWP-H was elucidated by partial degradation, methylation analysis combined with GC-MS method and NMR spectroscopy. It had a weight-average molecular weight of 1.2 × 10 6 g/mol and high degree of branch of 0.57. The presence of abundant arabinogalactan-II and certain galactan side chains in POWP-H was verified by the T-Ara f (17.4%), 1,3,6-Gal p (11.8%), 1,3-Gal p (8.1%), T-Gal p (13.4%) and 1,4-Gal p (14.3%). The evidence for the RG-I backbone of POWP-H was demonstrated by the structure analysis of its degraded product POWP-H-H, which had the backbone of →4)-α-Gal p A-(1 → 2)-α-Rha p -(1 → 4)-α-Gal p A-(1 → 2,4)-α-Rha p -(1→ substituted by short side chain of β-Gal p -(1 → 4)-β-Gal p -(1→ at O -4 position of →2,4)-α-Rha p -(1 → . Moreover, the POWP-H-H was mainly O -acetylated at O -3 position of α-Rha p with 24.8% acetylation degree. In conclusion, POWP-H was mainly the highly branched and acetylated RG-I pectin with relative short RG-I backbone and abundant arabinogalactan II and certain galactan side chains. Besides, it adopted a flexible chain conformation in 0.1 M NaNO 3 solution.
✓ 已验证
产品关联
DOI
高影响因子
PHYTOCHEMISTRY
·
2021
·
IF 4.072
Lanlan Nie,Rui Li,Jie Huang,Lingling Wang,Mengjie Ma,Chunyue Huang,Tong Wu,Renjie Yan,Xiao Hu
Five undescribed abietane diterpenoids , dracocephalumoids A–E, together with six known analogues were isolated from the aqueous EtOH extract of aerial parts of Dracocephalum moldavica L.. The structures were elucidated through extensive analysis of spectroscopic data , and their absolute configurations were established by Mosher's method and time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculation. Cell-based anti-inflammatory assays displayed that dracocephalumoid A, uncinatone, trichotomone F and caryopterisoid C showed potent suppressive effects against TNF- α , IL-1 β or NO production in LPS-induced RAW 264.7 cells, with IC 50 values ranging from 1.12 to 5.84 μM. The structure-activity relationship of these compounds was also discussed.
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2021
·
IF 4.354
Jingjing Sun,Changying Song,Dongying Ma,Shigang Shen,Shuying Huo
In this study, l-methionine selenoxide (MetSeO) was used as an oxidant for the construction of peptide disulfide bonds. Excellent yields for various disulfide-containing peptides were achieved via the MetSeO oxidation method in different solvents and on a resin. Most importantly, the construction of disulfide bonds can be performed in the trifluoroacetic acid cocktail used for the cleavage of peptides from the resin, which obviates the steps of peptide purification and lyophilization. This facilitates and simplifies the synthesis of disulfide-containing peptides. Kinetic and mechanistic studies of the reaction between MetSeO and dithiothreitol (DTT, a model compound of dicysteine-containing peptide) show that the reaction is first order in both [MetSeO] and [DTT], and a reaction mechanism is proposed that can help us gain insights into the reaction of the oxidative synthesis of disulfide bonds via MetSeO oxidation.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2021
·
IF 5.062
Mengzhe Li,Xiaohua Shen,Miaoqing Liu,Jianjun Lu
L-lysine is used as a crystallization regulator, and a two-step synthesis method is adopted in a concentrated gel system, which provides a new route to synthesize of nano-sized TS-1 zeolite. The new synthesis strategy was used to successfully synthesize TS-1 zeolite with a particle size less than 100 nm. The rate of crystal nucleation is faster than the crystal growth at the low temperature in the first step. Introduction of L-lysine can prevent crystal growth to form nano-sized TS-1 zeolite at the high temperature in the second step. Meanwhile, L-lysine decrease the pH value of the gel system, which is favorable for Ti atoms to incorporate the TS-1 framework. TS-1 nanozeolite can effectively reduce the diffusion resistance, and nanozeolite has a large specific surface area and high stability. Therefore, TS-1 nanozeolite exhibits the excellent catalytic performance during the hydroxylation of benzene. The conversion of benzene has been greatly improved and the types of by-products are effectively reduced. The conversion of benzene reached 50.2%, and the yield of phenol was 30.8% without by-product benzoquinone. TS-1 nano-zeolite as a catalyst for benzene hydroxylation shows great potential in industrial application.
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2021
·
IF 5.221
Zhu Wen-Yuan,Niu Kun,Liu Peng,Fan Yu-Hang,Liu Zhi-Qiang,Zheng Yu-Guo
L-methionine is an important natural amino acid with broad application prospects. A novel gene encoding the enzyme with the ability to catalyze O-succinyl-L-homoserine (OSH) to L-methionine was screened and characterized. The recombinant O-succinyl-L-homoserine sulfhydrylase from Thioalkalivibrio sulfidiphilus (tsOSHS) exhibited maximum activity at 35°C and pH 6.5. OSHS displayed an excellent thermostability with a half-life of 21.72 h at 30°C. Furthermore, the activity of OSHS increased 115% after Fe2+ added. L-methionine was obtained with a total yield reaching 42.63 g/L under the concentration of O-succinyl-L-homoserine 400 mM (87.6 g/L). These results indicated that OSHS is a potential candidate for applying in the large-scale bioproduction of L-methionine.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2021
·Vol. 13
·期 8
·1270
·
IF 4.329
Mengyuan Zhang,Zhonghua Chang,Xiaofeng Wang,Qian Li
Biodegradable and bioabsorbable polymers have drawn considerable attention because of their mechanical properties that mimic human soft tissue. Poly(l-lactide-co-ε-caprolactone) (PLCL), the copolymer of L-lactic (LA) and ε-caprolactone (CL), has been applied in many tissue engineering and regenerative medicine fields. However, both the synthesis of PLCL and the structure-activity relationship of the copolymer need to be further investigated to allow tuning of different mechanical properties. The synthesis conditions of PLCL were optimized to increase the yield and improve the copolymer properties. The synthetic process was evaluated by while varying the molar ratio of the monomers and polymerization time. The mechanical properties of the copolymer were investigated from the macroscopic and microscopic perspectives. Changes in the polymerization time and feed ratio resulted in the difference in the LA and CL content, which, in turn, caused the PLCL to exhibit different properties. The PLCL obtained with a feed ratio of 1:1 (LA:CL) and a polymerization time of 30 h has the best toughness and elasticity. The developed PLCL may have applications in dynamic mechanical environment, such as vascular tissue engineering.Keywords:poly(l-lactide-co-ε-caprolactone);synthesis;segment;toughness;elasticity
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2020
·
IF 7.182
Hao Wu,Shuqian Hu,Chunling Nie,Jiahui Zhang,Huafeng Tian,Weicheng Hu,Ting Shen,Jianguo Wang
Pathogens in the food and environment pose a great threat to human health. To solve this problem, we described a novel route to synthesize antibacterial epsilon-poly-L-lysine (EPL) anchored dicarboxyl cellulose beads. Cellulose beads were prepared via a sol-gel transition method and oxidized by sodium periodate and sodium chlorite to form carboxyl groups. EPL was anchored on the beads using carbodiimide mediated amidation. The structure and morphology of beads were characterized by FTIR, XPS, XRD, SEM, and TGA. After dissolution and regeneration, the crystalline form of cellulose is transformed from cellulose I to cellulose II. The thermal degradation temperature of the beads is 200∼300 °C.The samples displayed excellent antimicrobial activity against Staphylococcus aureus , Alicyclobacillus acidoterrestris and Escherichia coli within 12 h. The beads could be biodegraded in soil after 20 days. The biodegradable beads exhibited great potential in food and environmental applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Zhicheng Gao,Ying Li,Xunqiu Wang
In this study, the solubility of l -malic acid in three binary solvents (ethyl acetate + tetrahydrofuran , acetonitrile + tetrahydrofuran, butyl acetate + acetonitrile) at atmospheric pressure from T = (278.15 to 323.15) K was measured via a gravimetric method. The results show that in the temperature range studied, the solubility of l -malic acid in the selected solvent gradually increases with the increase of temperature. The solubility of l -malic acid increases with the increase of the mass fraction of tetrahydrofuran at the binary system (ethyl acetate + tetrahydrofuran, acetonitrile + tetrahydrofuran), the solubility of l -malic acid increases with The mass fraction of butyl acetate increases and decreases at the butyl acetate + acetonitrile system. In addition, the dissolution behavior of l -malic acid was explained using Hansen solubility parameter (HSP). Furthermore, the solubility data were correlated with using the modified Apelblat equation, the NRTL model and the newly proposed Apelblat-Sun model, the results have shown that the modified Apelblat equation has the best fitting effect. After research found, the hydrogen bonding force plays a key role in the solubility of l -malic acid. So solubility of l - resulted malic acid from the integrated effect of solute–solvent and solvent–solvent interactions. In addition, the van't Hoff equation was used to calculate and discuss all thermodynamic parameters of dissolution, Including standard Gibbs dissolution (Δ sol G o ), standard dissolution enthalpy (Δ sol H o ) and standard dissolution entropy (Δ sol S o ), Where Δ sol H o ，Δ sol S o ，Δ sol G o were all greater than 0, it have been shown that the dissolution process is driven by heat absorption and entropy. This study can provide basic thermodynamic data for the crystallization and industrial separation of l -malic acid.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2020
·Vol. 27
·期 8
·1-10
·
IF 2.426
Han Shuo,Peng Yanyan,Tao Shengyun,Hu Ying,Lan Tianqi,Hu Chengkang,Cao Jing
In this work, a kind of chiral helical polymer PDTDH of 9,9-dipropynylfluorene skeleton structure were prepared. The structure and chiral properties of the obtained polymer were characterized by Nuclear Magnetic Resonance (NMR) and Circular Dichroism (CD) Spectroscopy. These chiral PDTDH polymers were used to fabricate chiral sensors and to investigate the enantioselective recognition of D−/L- tartaric acid enatiomer. The results indicated that the (S)-PDTDH/GCE sensor showed obvious response toward the tested tartaric acid enantiomer, which was confirmed by two parameters: Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) tests. These findings expand the scope for the application of chiral polymer as electrode modification material in the electrochemical chiral recognition field.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）