INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2022
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IF 8.025
Zi-Fu Ni,Na Li,Pei Xu,Ze-Wang Guo,Min-Hua Zong,Wen-Yong Lou
Ammonia lyases have great application potential in food and pharmaceuticals owing to their unique ammonia addition reaction and atom economy. A novel methylaspartate ammonia-lyase, Ec MAL, from E. coli O157:H7 showed high catalytic activity. To further strengthen its thermostability and activity, disulfide bond and backbone cyclization (cyclase) variants were constructed by rational design, respectively. Among them, variant M3, with a disulfide bond introduced, exhibited a 2.3-fold increase in half-life at 50 °C, while cyclase variant M8 showed better performance, with 25.9-fold increases. The synergistic promotion effect of this combinational strategy on activity and stability was also investigated, and the combined mutant M9 exhibited a 1.1-fold improvement in catalytic efficiency while maintaining good thermostability. Circular dichroism analysis and molecular dynamics simulation confirmed that the main sources of improved thermostability were reduced atomic fluctuation and a more stable secondary structure. To our knowledge, this is the first example of combining the introduction of disulfide bonds with cyclase construction to improve enzyme stability, which was characterized by modification away from the enzyme active center, and provided a new method for adjusting enzyme thermostability.
研究领域:
生物化学
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蛋白质工程
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2017
·
IF 3.671
Jiandong Cui,Yamin Zhao,Zhilei Tan,Cheng Zhong,Peipei Han,Shiru Jia
Cross-linked enzyme aggregates (CLEAs) have recently emerged as a promising method for enzyme immobilization due to its simplicity and low cost. However, a lack of good size and morphological control over the as-prepared CLEAs has limited their practical applications in some cases. Here, monodisperse spherical CLEAs of phenylalanine ammonia lyase (PAL microspheres) were prepared based on CaCO 3 microtemplates. The preparation procedure involves filling porous CaCO 3 microtemplates with the protein by salt precipitation, glutaraldehyde crosslinking, and dissolution of the microtemplates. The formulation of CaCO 3 templates with controlled size was studied in detail. Characterization of the prepared PAL microspheres was investigated. The results showed that the PAL microspheres with high immobilization efficiency (79%) exhibited excellent stability, including increased tolerance to proteolysis , low pH, and denaturants, and excellent mechanical properties. For example, free PAL almost lost all activity after they were incubated in the presence of trypsin for 2 min, whereas PAL microspheres still retained 95% of their initial activity. Moreover, scanning electron microscope , transmission electron microscope, and N 2 adsorption-desorption isotherms revealed that the resultant PAL microspheres possessed good monodispersity and mesoporous structure instead of the amorphous clusters of conventional CLEAs with few pores. Compared with conventional CLEAs, the monodisperse PAL microspheres with mesoporous make them more potentially useful for biomedical and biotechnological applications.
研究领域:
生物技术
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酶工程
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材料科学
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DOI
高影响因子
BMC Chemistry
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2020
·Vol. 14
·期 1
·1-7
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IF 0
Ye Changwen,He Chen,Zhang Bowen,Wang Lixuan,Wang Lufeng
Zizania latifolia is easily lignified after harvesting, leading to the degradation of food quality and commercial value. Thus, this study evaluated the effect of radio frequency (RF) treatments on lignification inhibition of Zizania latifolia . The results showed that the lignin content of Zizania latifolia treated with RF decreased significantly compared with the control group. At the 7th day of storage, the phenylalanine ammonia lyase activity of the 90 W RF treatment group decreased by 52.9% compared with the initial value. The activities of peroxidase and polyphenol oxidase in the stems of Zizania latifolia were significantly ( p < 0.05) decreased after RF treatments. Besides, a decrease in conversion rate of O 2 − and H 2 O 2 to downstream products was observed, indicating that the related invertases were inhibited by RF treatment. All of these showed that RF treatments contribute to inhibit or delay the lignification of Zizania latifolia , providing a better taste and quality for products.
研究领域:
植物学
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食品科学
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农业科学
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产品关联
DOI
PubMed
BIOCHEMICAL ENGINEERING JOURNAL
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2022
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IF 4.446
Jiaheng Wang,Nuo Zhang,Yawen Huang,Shunyi Li,Guimin Zhang
p -Coumaric acid (para-hydroxycinnamic acid, p -HCA), as a kind of natural active substance from plant cell walls, is widely used in medicine, food, and cosmetics with its antioxidant, anticancer, and other properties. Biological production of p -HCA can be achieved via one-step deamination of the L -tyrosine by tyrosine ammonia-lyase (TAL). Here, a new highly active TAL ( Fc -TAL) from Flavobacterium columnare was identified via gene mining and heterologous expression . The purified Fc -TAL completely converts 22 mM L -tyrosine to p -HCA under alkaline condition (pH 9.5–10.0) at 55 °C. To increase enzymatic recyclability and reduce the bioproduction cost, Fc -TAL was immobilized on a silica nanospheres through silica-binding peptides (SiBP2) at pH 10. In comparison to free enzyme , the immobilized TAL SiBP2 exhibited higher stability, over 50% activity was retained even after 10 consecutive catalytic cycles. Further experiments revealed that an aliquot of immobilized enzyme (about 200 mg TAL) can transform 20 g L -tyrosine into17.8 g p -HCA with 96% yields and 98% purity through 5 consecutive reaction cycles. Our studies not only provided a strategy for enzyme immobilization in alkaline condition, but also developed a green process for p -coumaric acid biosynthesis with the highest conversion rate and yield reported to date.
研究领域:
生物化学
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生物技术
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酶学
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药学
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产品关联
DOI
高影响因子
SCIENTIA HORTICULTURAE
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2024
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IF 3.9
Xinping Wu,Qiuying Li,Yang Yi,Limei Wang,Wenfu Hou,Youwei Ai,Hongxun Wang,Ting Min
The quality of fresh-cut Chinese water chestnuts (CWCs) rapidly deteriorates with prolonged storage time, thus affecting its commercial value. This study aimed to investigate the effect of cinnamaldehyde (CA) treatment on the quality of fresh-cut CWCs and its mechanism of action. CA treatment maintained good appearance and higher total soluble solids content (TSS) of fresh-cut CWCs and also significantly inhibited microbial proliferation, respiration, phenylalanine ammonia-lyase activity (PAL) and enzymatic browning substance content. Moreover, CA treatment increased the antioxidant capacity and defense function-related enzyme activities (PPO and POD) of fresh-cut CWCs, and suppressed ·OH production rate and MDA content. Meanwhile, CA treatment significantly increased the content of antioxidant compounds and enzyme activities of the AsA-GSH cycle system. In conclusion, CA can inhibit surface discoloration of fresh-cut CWCs and extend their shelf life, thus increasing their commercial value.
研究领域:
食品科学
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采后生理学
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植物生物化学
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DOI
高影响因子
Nature Catalysis
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2021
·Vol. 4
·期 5
·364-373
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IF 41.813
Cui Yinglu,Wang Yinghui,Tian Wenya,Bu Yifan,Li Tao,Cui Xuexian,Zhu Tong,Li Ruifeng,Wu Bian
Although C–N bonds are ubiquitous in natural products, pharmaceuticals and agrochemicals, biocatalysts forging these bonds with high atom-efficiency and enantioselectivity have been limited to a few select enzymes. In particular, ammonia lyases have emerged as powerful catalysts to access C–N bond formation via hydroamination. However, the use of ammonia lyases is rather restricted due to their narrow synthetic scope. Herein, we report the computational redesign of aspartase, a highly specific ammonia lyase, to yield C–N lyases with cross-compatibility of non-native nucleophiles and electrophiles. A wide range of non-canonical amino acids (ncAAs) are afforded with excellent conversion (up to 99%), regioselectivity >99% and enantioselectivity >99%. The process is scalable under industrially relevant protocols (exemplified in kilogram-scale synthesis) and can be facilely integrated in cascade reactions (demonstrated in the synthesis of β-lactams with N-1 and C-4 substitutions). This versatile and efficient C–N lyase platform supports the preparation of ncAAs and their derivatives, and will present opportunities in synthetic biology.
研究领域:
生物催化
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酶工程
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有机化学
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合成生物学
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DOI
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
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2023
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IF 3.9
Shiming Tang,Yukun Chen,Daocheng Liao,Ying Lin,Shuangyan Han,Suiping Zheng
As an essential chemical, p- hydroxystyrene has attracted much attention and is widely used in the field of semiconductors. However, the current production methods have some disadvantages, such as low molar conversion yield, p- hydroxystyrene toxicity, and high substrate cost. To overcome these problems, an five enzymes cell-free cascade, consisting of alditol oxidase from Streptomyces coelicolor A3 (ScALDO), dehydratase from Paralcaligenes ureilyticus (PuDHT), tyrosine phenol lyase from Citrobacter freundii (CfTPL), tyrosine ammonia lyase from Rhodotorula glutinis (RgTAL) and phenylacrylate decarboxylase from Enterobacter sp. (EsPAD ) , was constructed for the de novo biosynthesis of p- hydroxystyrene from glycerol. Through process strategy optimization, a molar conversion yield of more than 84.2% was finally obtained from 10 mM crude glycerol. It is worth mentioning that the reaction system performed an excellent titer using 50 mM crude glycerol, and the p- hydroxystyrene concentration reached 30.32 mM, which exceeded the maximum titer of fermentation. This showed that our system is robust to p- hydroxystyrene and crude glycerol. In addition, a ‘two-step purification process’ was designed to produce pure p- hydroxystyrene. This is the first study focused on the cell-free biosynthesis of p- hydroxystyrene, and the highest conversion yield and titer thus far was obtained for p- hydroxystyrene de novo biosynthesis.
研究领域:
化学工程
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生物技术
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生物化学
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产品关联
DOI
高影响因子
Journal of Future Foods
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2022
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IF 0
Yue Chen,Yong Zhu,Likang Qin
ABSTRACT In order to study the changes and mechanism of phenolic compounds during Tartary buckwheat germination, the dynamic changes of phenolic compounds were analyzed, and the activities of enzymes that regulate phenolic compound biosynthesis and degradation were monitored. Total phenolics and total flavonoids presented an interesting dynamic trend with the extension of the germination time, and rutin, gallic acid, chlorogenic acid as well as 2,3,4-trihydroxybenzoic acid contents showed an increasing trend during germination period, the contents were up to (2 663.4 ± 61.1), (449.12 ± 5.26), (99.953 ± 7.800) and (50.442 ± 1.477) mg/100 g DW, respectively. Phenylalanine ammonia lyase (PAL) and chalcone isomerase (CHI) are dominant enzymes in regulating phenolic compound biosynthesis, which showed an increasing trend. Rutin degrading enzyme (RDEs) is the key enzyme in regulating phenolic compound degradation, which showed a decreasing trend. These results suggested that germination processing increases the phenolic compound contents of Tartary buckwheat, which may be regulated by the activation of PAL, CHI and the inhibition of RDEs.
研究领域:
植物科学
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生物化学
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食品科学
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DOI
Cell Host & Microbe
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2024
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IF 20.6
Dongping Li,Meijuan Wan,Lanfeng Xue,Zhelin Zhang,Yifeng Qiu,Fengyi Mei,Niexing Tang,Chunxiao Yu,Yao Yu,Tianqi Chen,Xing Ding,Qin Yang,Qiuyan Liu,Peng Gu,Wei Jia,Yu Chen,Peng Chen
Cholestatic liver disease (CLD) is a common liver disorder with limited treatment options. Here, we demonstrate that zinc (Zn) supplementation can alter the gut microbiome to mitigate cholestatic liver injury. Oral Zn altered the microbiota of mice and humans (this study was registered at clinicaltrials.gov [NCT05597137]), increasing the abundance of Blautia producta ( B. producta ) and promoting the generation of p-coumaric acid. Additionally, p-coumaric acid concentrations were negatively correlated with liver injury parameters in CLD patients. In mice, the protective effects of Zn were partially mediated by p-coumaric acid, which directly bound to nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) and suppressed the production of reactive oxygen species (ROS) in hepatocytes, thus preventing hepatocyte cell death and liver damage. Additionally, knocking out the histidine ammonia-lyase, which catalyzes the conversion of tyrosine to p-coumaric acid in B. producta , blunted the protective effects of Zn. These findings highlight a host-microbiota interaction that is stimulated by Zn supplementation, providing potential benefits for CLD.
研究领域:
胃肠病学
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微生物学
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药理学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Plants-Basel
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2024
·Vol. 13
·期 5
·732
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IF 4
Xuejie Du,Xinqiao Zhan,Xueting Gu,Xinyi Liu,Bizeng Mao
The shoot apical meristem culture has been used widely to produce virus-free plantlets which have the advantages of strong disease resistance, high yield, and prosperous growth potential. However, this virus-free plant will be naturally reinfected in the field. The physiological and metabolic responses in the reinfected plant are still unknown. The flower of chrysanthemum ‘Hangju’ is a traditional medicine which is unique to China. In this study, we found that the virus-free ‘Hangju’ (VFH) was reinfected with chrysanthemum virus B/R in the field. However, the reinfected VFH (RVFH) exhibited an increased yield and medicinal components compared with virus-infected ‘Hangju’ (VIH). Comparative analysis of transcriptomes was performed to explore the molecular response mechanisms of the RVFH to CVB infection. A total of 6223 differentially expressed genes (DEGs) were identified in the RVFH vs. the VIH. KEGG enrichment and physiological analyses indicated that treatment with the virus-free technology significantly mitigated the plants’ lipid and galactose metabolic stress responses in the RVFH. Furthermore, GO enrichment showed that plant viral diseases affected salicylic acid (SA)-related processes in the RVFH. Specifically, we found that phenylalanine ammonia-lyase (PAL) genes played a major role in defense-related SA biosynthesis in ‘Hangju’. These findings provided new insights into the molecular mechanisms underlying plant virus–host interactions and have implications for developing strategies to improve plant resistance against viruses.
研究领域:
植物病理学
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分子生物学
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农学
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药理学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
·
IF 15.1
Changqing Jin,Fanglin Wu,Haibo Tang,Hongfei Pan,Zhida Chen,Rui Wang,Zihan Meng,Junsheng Li,Haolin Tang
The development of catalysts for hydrogen oxidation reaction (HOR) with enhanced resistance to ammonia poisoning is an important factor in the practical application of hydrogen electrochemical purification devices (HEPDs). This paper reports on the creation of a highly active and anti-ammonia HOR catalyst developed by tuning the charge distribution of the support material through nitrogen-doping of carbon. The nitrogen-doped carbon-supported platinum catalyst (Pt-N 2 /KB, 2.03 wt% Pt) achieves a high mass activity and exchange current density of 2788 mA mg pt -1 and 1020 mA mg pt -1 , respectively, which are 5.4 and 4.7 times higher than that of the comm. 20% Pt/C. The Pt-N 2 /KB catalyst also displays a lower percentage of current decay and enhanced electrochemical stability, indicating superior anti-ammonia toxicity in the tests with HEPD. Density functional theory (DFT) calculations reveal that the hydrogen adsorption free energy (ΔG H* ) on the surface of Pt-N 2 /KB is close to zero and has a lower ammonia adsorption energy, thus accounting for its superior HOR activity and anti- ammonia poisoning ability. Consequently, this work facilitates the implementation of HOR catalysts for anti-ammonia poisoning in the HEPDs, thus accelerating the advancement of ammonia cracking for hydrogen production .
研究领域:
催化
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电化学
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材料科学
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能源工程
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化工
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2021
·
IF 5.279
Ou Chen,Lili Deng,Changqing Ruan,Lanhua Yi,Kaifang Zeng
This study aimed to investigate the effect of Pichia galeiformis on disease resistance and elucidate the changes in phenylpropane biosynthesis treated by P. galeiformis in postharvest citrus. The results showed that P. galeiformis reduced the disease incidence and lesion diameters without direct contact with the pathogen Penicillium digitatum. Transcriptome analysis revealed that phenylpropanoid biosynthesis was triggered by P. galeiformis. Genes encoding phenylpropanoid biosynthesis were upregulated, including phenylalanine ammonia-lyase (PAL), 4-coumaroyl-CoA ligase (4CL), cinnamate-4-hydroxylase (C4H), peroxidase (POD), cinnamyl alcohol dehydrogenase (CAD), O-methyltransferase, and hydroxyl cinnamoyl transferase. Moreover, P. galeiformis increased the activity of PAL, 4CL, C4H, POD, polyphenol oxidase, and CAD in citrus pericarp. In addition, P. galeiformis treated citrus displayed higher levels of total phenolic compounds, flavonoid, and lignin and higher amounts of ferulic and sinapic acid. In conclusion, these results suggested that P. galeiformis could induce resistance through modulating the pathway of phenylpropanoid biosynthesis in postharvest citrus.
研究领域:
植物病理学
·
分子生物学
·
采后生理学
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生物化学
✓ 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）