BIOORGANIC CHEMISTRY
·
2023
·
IF 5.1
Yangyang Sun,Zhuzhu Tang,Yanjun Li,Yongkang Song,Hualei Wang,Dongzhi Wei,Shengli Yang
Hydration, a secondary activity mediated by nitrilase, is a promising new pathway for amide production. However, low hydration activity of nitrilase or trade-off between hydration and catalytic activity hinders its application in the production of amides. Here, natural C-terminal-truncated wild-type nitrilase, mined from a public database, obtained a high-hydration activity nitrilase as a novel evolutionary starting point for further protein engineering. The nitrilase Nit-74 from Spirosoma linguale DSM 74 was successfully obtained and exhibited the highest hydration activity level, performing 50.7 % nicotinamide formation and 87.6 % conversion to 2 mM substrate 3-cyanopyridine. Steric hindrance of the catalytic activity center and the N -terminus of the catalytic cysteine residue helped us identify three key residues: I166, W168, and T191. Saturation mutations resulted in three single mutants that further improved the hydration activity of N -heterocyclic nitriles. Among them, the mutant T191S performed 72.7 % nicotinamide formation, which was much higher than the previously reported highest level of 18.7 %. Additionally, mutants I166N and W168Y exhibited a 97.5 % 2-picolinamide ratio and 97.7 % isonicotinamide ratio without any loss of catalytic activity, which did not indicate a trade-off effect. Our results expand the screening and evolution library of promiscuous nitrilases with high hydration activity for amide formation.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2023
·
IF 4.6
Yangyang Sun,Zhuzhu Tang,Tingze Pan,Ke Zhang,Liuzhu Wang,Xingye Zhai,Yiran Jia,Tianqi Yuan,Yujia Qian,Hualei Wang,Dongzhi Wei,Shengli Yang
Catalytic promiscuity makes nitrilase-mediated unnatural reactivity a promising pathway in the production of primary amides . However, during the functional switch of nitrilase, a trade-off between the newly developed hydration activity and relative activity hinders the application of nitrilase in the production of amides. Our previous study showed that the mutant F193N (Mut0) of nitrilase NIT6803 from Synechocystis sp. PCC6803 improved the hydration activity as the amide ratio increased to 73.4%, whereas the relative activity was only 50.1% of that of the wild-type (WT). In this study, we succeeded in alleviating the trade-off of Mut0 through an evolutionary combination of the key identified sites 101, 192, and 201. Inside the active pocket, the co-evolution of residue Q192 was identified by hotspot prediction to correlate with N193, and Q192H exhibited an improved amide ratio of 76.9% with a relative activity of up to 72%. Outside the active pocket, the flexible loop surface residue G101 and homodimer “A” interface residue I201 were identified using sequence alignment-based mutations. Further evolutionary combination of the three key sites yielded the best triple mutant G101K/Q192H/I201M, which had the highest amide ratio of 98.5% and considerably recovered relative activity of 82.6% while retaining only 1.5% of the carboxylic acid ratio. The transition-state analogue sheds light on the basis of the almost identical switch of the reaction pathways, and our results expand the toolbox of nitrilase-catalysed promiscuity for amide formation.
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 10
·4164
·
IF 4.6
Jassim Mohamed Hamed Al-Kurdhani,Huajun Wang
A series of supported CuO-based nanoparticle catalysts were prepared by the impregnation method and used for the synthesis of glycerol carbonate from glycerol and CO2in the presence of 2-cyanopyridine as a dehydrant and DMF as a solvent. The effects of supports (activated alumina, silicon dioxide, graphene oxide, graphene, and activated carbon), CuO loading amount, calcination temperature, and reaction parameters on the catalytic activity of the catalyst were investigated in detail. XRD, FTIR, SEM, BET, and CO2-TPD were used for the characterization of the prepared catalysts. It is found that CuO/Al2O3shows a higher catalytic activity, which depends on the CuO loading amount and calcination temperature. The surface area and number of basic sites of the catalyst exhibit a crucial effect on the catalytic activity of CuO/Al2O3. Furthermore, there is a synergistic effect between the catalyst and 2-cyanopyridine where the former has a higher activation ability for glycerol and the latter acts not only as a dehydrant, but also as a promoter for CO2activation. Recycling experiments reveal that this catalyst can be reused for at least five cycles without any inactivation. Based on the experiment results and FTIR characterization, a possible reaction mechanism for the carbonylation of glycerol and CO2is proposed.Keywords:glycerol;glycerol carbonate;carbon dioxide;2-cyanopyridine;CuO/Al2O3
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Qinglong Li,Yong Hou,Yunjing Xing,Yumeng Wang,Zhonghao Sun,Zhaocui Sun,Xudong Xu,Longfei Yang,Xiaowei Huo,Guoxu Ma
The rotting of fresh fruits is a great challenge in the food industry for the whole world, which also easily result in more severe social problem such as food shortages, environmental pollution and health hazards. Microbial contamination is the main cause of fruits rotting, but cannot be solved by conventional methods like waxing, refrigeration, or vacuum packaging currently. Leveraging the multiple bioactivities and unique assembly function of natural small molecules, we have firstly achieved the directed co-assembly of binary natural small molecules (resveratrol and piceid) into a carrier-free gel by a simple heat-cooling method for perishable fruits preservation. It was proven that hydrogen bonding and π-π stacking interactions were the main driving forces for the co-assembly of binary molecules. And Res-Pic gel had been demonstrated to possess synergistic antioxidant, antibacterial, and biofilm removal properties compared to corresponding monomer . After sprayed on the surface of fruits, it was found to significantly inhibit microbial reproduction, prevent browning, reduce water and nutrient loss. Especially it had realized to ultimately decrease the corruption rate by 36.81% of cherries comparing with the untreated group during storage at room temperature. Furthermore, experimental study in vivo showed its excellent biocompatibility , thus avoiding the health risk from mis-eating. Such a directed co-assembly strategy based on binary NSMs have provided a simple, low-cost, biosafe gel products with enhanced biological activity , and further showed great prospects for perishable food preservation.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
·
2025
·
IF 5.2
Chenyu Wu,Zijian Wang,Xu Han,Xinyi Yu,Changquan Calvin Sun,Zhengzheng Zhou
Diclofenac (DIC) is a nonsteroidal anti-inflammatory drug with poor tabletability and water solubility. In the present study, a new diclofenac-picolinamide cocrystal (DIC-PIC) was prepared to simultaneously improve its tabletability and solubility. The cocrystal was characterized using multiple techniques, such as X-ray diffraction, thermal methods and spectral analyses. The tabletability of DIC-PIC was significantly improved over DIC, which is attributed to the larger bonding area between crystals due to the higher plasticity of DIC-PIC, demonstrated by the lower in-die mean yield pressure, P y,i , of DIC-PIC (59.5 ± 0.6 MPa) than DIC (86.6 ± 1.4 MPa). The higher plasticity of DIC-PIC is consistent with the existence of a slip plane (001) in its crystal structure. The thermodynamic solubility of DIC-PIC is significantly higher than that of DIC (112 times higher in water and 22 times higher in pH = 6.8 buffer solution). Hence, the simultaneous improvement in tabletability and solubility of DIC-PIC overcomes two main barriers in developing DIC tablets, which makes it a promising candidate for developing a DIC tablet with improved performance.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2025
·
IF 5.9
Ruilu Sun,Wei Li,Minjie Liao,Yiran Yu,Yao Mou,Junfu Ji,Fang Chen,Xiaosong Hu,Lingjun Ma
Resveratrol (RES) and its catechol analog piceatannol (PIC), natural polyphenols, exhibit benefits in relieving glucose metabolism disorders. This study compared their effects on glucose metabolism regulation through in vivo and in vitro studies combined with quantitative analysis. Results showed that PIC significantly ameliorated insulin resistance and inhibited gluconeogenesis in obese mice, exhibiting superior efficacy to RES. Specifically, the area under the curve (AUC) of the intraperitoneal glucose tolerance test (IPGTT) was 2007.38 mmol・L −1 ・h for PIC, lower than 2450.88 mmol・L −1 ・h for RES; the phosphoenolpyruvate carboxykinase (PEPCK) concentration was 172.80 ng・L −1 in the PIC group, lower than 182.12 ng・L −1 in the RES group. At equimolar phenolic hydroxyl concentrations, PIC promoted greater glucose uptake and glycogen accumulation in human hepatocellular carcinoma (HepG2) cells compared to RES. Additionally, PIC accelerated tricarboxylic acid (TCA) cycle flux toward glucose utilization. These findings indicate that PIC is more effective than RES in regulating glucose metabolism, highlighting the critical role of the catechol moiety. This study provides guidance for screening natural bioactive polyphenols.
✓ 已验证
产品关联
DOI
高影响因子
Journal of CO2 Utilization
·
2024
·
IF 7.2
Xiaomeng Deng,Wensheng Wei,Zizhen Yan,Zhanguo Zhang,Yuxin Wang,Guangwen Xu,Jianjun Guo,Jinggang Zhao,Lei Shi
A meaningful and practical phenomenon was observed and investigated, about which a synthesized (2-hydroxyethyl) triethylammonium bromide (NEt 3 (HE)Br) was used for catalytic cycloaddition of PO (propylene oxide) and CO 2 (carbon dioxide) in a homogeneous state, and then separated from the reaction system in a heterogeneous state. The target products were first reported as additives to regulate the distribution of reactants and carbon dioxide (CO 2 ) in the gas-liquid phase, as well as to facilitate the dissolution of NEt 3 (HE)Br. Under the optimal conditions of 0.2 mol% NEt 3 (HE)Br dosage, the PC yield (98.71 %) and TOF value (22.54 h −1 ) reached are significantly higher than the case of without PC addition. Besides, NEt 3 (HE)Br exhibited impressive stability after five catalytic cycles. The catalytic performances of different additives (i.e., alcohols, cyclic carbonate, amides, sulfones, petroleum ether, straight-chain carbonate and oxalate) were investigated, and their promotional effects and mechanisms were systematically elucidated. The transition behavior of dissolution-catalysis-precipitation process and intrinsic promoting mechanism of NEt 3 (HE)Br gave an efficient idea for a homogeneous catalytic reaction and heterogeneous separation of the catalyst. Meanwhile, this work provides an important theoretical and practical basis for efficient and facile catalyst synthesis and the corresponding reaction system design.
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2025
·Vol. 15
·期 5
·361
·
IF 4.3
Peiru Li,Siyuan Guo,Yunan Liu,Yanhong Lin,Tengfeng Xie
The periodical distribution of N and C atoms in carbon nitride (CN) not only results in localized electrons in each tri-s-triazine unit, but oxidation and reduction sites are in close contact spatially, resulting in severe carrier recombination. Herein, the hydrothermal method was first employed to synthesize carbon nitride (HCN), and then picolinamide (Pic) molecules were introduced at the edge of the carbon nitride so that the photo-generated electrons of the whole structure of the carbon nitride system were transferred from the center to the edge, which effectively promoted the separation of photo-generated carriers and inhibited the recombination of carriers in the structure. The introduced picolinamide not only changed the π-conjugated structure of the entire system but also acted as an electron-withdrawing group to promote charge transfer. The photocatalytic hydrogen evolution rate (HER) of the optimized HCN-Pic-1:1 sample could reach 918.03 μmolg −1 h −1 , which was 11.8 times higher than that of the HCN, and the performance also improved.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）