JOURNAL OF MEDICINAL CHEMISTRY
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2024
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IF 6.8
Xin Xiang,Chuning Dong,Lianbo Zhou,Jun Liu,Zachary M. Rabinowitz,Yuzhao Zhang,Honghui Guo,Feng He,Xingdou Chen,Yunhua Wang,Lina Cui,Xiaowei Ma
Real-time detection of cellular senescence remains a clinical challenge. Here, we aimed to develop a positron emission tomography (PET) imaging probe targeting senescence-associated β-galactosidase (SA-β-Gal), the most widely used biomarker of cellular senescence, and investigate its performance for real-time in vivo quantitative detection of cellular senescence. A stable PET imaging agent [68Ga]Ga-BGal was obtained with a high labeling yield (90.0 ± 4.3%) and a radiochemical purity (>95%). [68Ga]Ga-BGal displayed high sensitivity and specificity for β-Gal both in vitro and in vivo. The reaction and uptake of the probe correlated with the β-Gal concentration and reaction time. In PET imaging, high β-Gal-expressing CT26.CL25 tumors and doxorubicin-treated HeLa tumors showed high signals from [68Ga]Ga-BGal, while a low signal was observed in CT26.WT and untreated HeLa tumors. In summary, we showcased successful PET imaging of senescence in preclinical models using probe [68Ga]Ga-BGal. This finding holds the potential for translating senescence imaging into clinical applications.
研究领域:
医学影像学
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分子生物学
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肿瘤学
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放射学
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药学
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产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2025
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IF 9
Jingwen Zhang,Binge Zhang,Feiyu Duan,Zehui Xuan,Tong Sun,Lili Lu
β-Galactosidases are important enzymatic tools for glycosylation, but their properties vary greatly with the source. Here, ten putative β-galactosidase genes, designated as bga 1 to bga 10, encoding proteins Bga1 to Bga10, were mined from an environmental metagenomic dataset comprising 119,152 sequences. Five of the encoded enzyme proteins exhibited less than 80% sequence similarity to known enzymes, but displayed conserved catalytic sites in their predicted three-dimensional models. After heterologous expression and characterization, two recombinant enzymes showed specific hydrolysis activity toward o -nitrophenyl-β- d -galactopyranoside. One of them, Bga4R, exhibited remarkable activity at pH 7.4 and 50℃, with excellent alkaline stability. Notably, Bga4R tolerated a wide range of acceptors for transglycosylation. It catalyzed galactosyl transfer to various monosaccharides and sugar alcohols, and enabling the synthesis of diverse glycosylated derivatives. This study identifies a novel GH 1 β-galactosidase as a powerful tool for glycosylation engineering, with promising potential for synthesizing galactosides valuable to food and pharmaceutical industries.
研究领域:
生物化学
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微生物学
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合成生物学
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产品关联
DOI
PubMed
高影响因子
Food & Function
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2015
·Vol. 6
·期 10
·3291-3295
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IF 2.791
Hui-da Wan,Yong-mei Xia
Enzymatic hydrolysis and transgalactosylation of stevioside (St) were investigated using a β-galactosidase from Sulfolobus sp. The hydrolysis yielded steviol as the main final product. Under the optimal transgalactosylation conditions, the highest conversion of stevioside was 87.3% with lactose as a donor, several galactosylated products (St-Gals) were obtained. Metal ions such as Na+, K2+, Ca2+, Ba2+, Mn2+ and Mg2+ (2 mM) did not affect the transgalactosylation activity, while Fe2+, Fe3+ and Cu2+ reduced the transgalactosylation activity of β-galactosidase to 64%, 33% and 18%, respectively.
研究领域:
生物化学
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食品科学
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DOI
高影响因子
FOOD CHEMISTRY
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2013
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IF 3.334
Wei Wei,Danping Qi,Hai-zhen Zhao,Zhao-xin Lu,Fengxia Lv,Xiaomei Bie
A study of an enzymatic method for the production of galactosylglycerol is described. The effects of enzyme sources, enzyme amount, reaction temperature, reaction time, substrate ratio of glycerol to galactose, buffer content and pH on galactosylglycerol yield (mg/ml) were investigated. Under the optimum reaction conditions of β-galactosidases from Kluyveromyces lactis 240 U/ml, temperature 40 °C, time 24 h, buffer amount 60% (percent volume of buffer to that of substrates, pH 6.5), and the substrate molar ratio of 10 (glycerol16 mmol:galactose 1.6 mmol), the yield of galactosylglycerol was up to 116.47 mg/ml (galactose conversion 55.88%). The product was purified by activated charcoal and Sephadex G-15 column chromatography, up to 96%. The purified galactosylglycerol was fully characterised by MS and NMR, and identified as a mixture of (2R)- and (2S)- 3-O-β-D-galactopyranosyl-glycerol.
研究领域:
生物化学
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酶工程
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产品关联
DOI
PubMed
高影响因子
GLYCOCONJUGATE JOURNAL
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2018
·Vol. 35
·期 3
·255-263
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IF 2.548
Guo Bi-Shan,Zheng Feng,Crouch Lucy,Cai Zhi-Peng,Wang Meng,Bolam David N.,Liu Li,Voglmeir Josef
A putative GH35 β-galactosidase gene from the mucin-degrading bacterium Akkermansia muciniphila was successfully cloned and further investigated. The recombinant enzyme with the molecular mass of 74 kDa was purified to homogeneity and biochemically characterised. The optimum temperature of the enzyme was 42 °C, and the optimum pH was determined to be pH 3.5. The addition of sodium dodecyl sulphate (SDS) reduced the enzyme’s activity significantly. The addition of Mg 2+ -ions decreased the activity of the β-galactosidase, whereas other metal ions or EDTA showed no inhibitory effect. The enzyme catalysed the hydrolysis of β1,3- and β1,6- linked galactose residues from various substrates, whereas only negligible amounts of β1,4-galactose were hydrolysed. The present study describes the first functional characterisation of a β-galactosidase from this human gut symbiont.
研究领域:
微生物学
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生物化学
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DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
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2020
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IF 2.952
Jiaying Zhu,Jiaqi Sun,YaJie Tang,Jingli Xie,Dongzhi Wei
A heterodimeric β-galactosidase was discovered in the novel strain Lactobacillus curieae M2011381. The gene encoding the enzyme was expressed in Escherichia coli BL21 (DE3). The specific enzyme activities of the recombinant holoenzyme (LacLM) and large subunit (LacL) measured 11.4 U/mg and 3.8 U/mg, respectively. The k cat /K m values of LacLM and LacL were 740 mM −1 s −1 and 1.40 mM −1 s −1 , respectively. LacLM showed maximum activity at pH 8.0 and 55 °C, and it could maintain its activity at a neutral pH and below 45 °C. LacLM displayed both hydrolysis and transgalactosylation activity on 200 g/L lactose. When LacLM was added to milk, the lactose was hydrolyzed after 6 h without galactooligosaccharide generation. The sequence alignment and homology modeling of the structures of the holoenzyme and subunits revealed that LacL has a catalytic domain with a catalytic dyad, Glu470 and Glu538, and small subunit LacM is a β-sheet domain with a conserved Trp294. The molecular docking of LacLM helped to illustrate the roles of both subunits in the reaction with lactose.
研究领域:
微生物学
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酶学
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生物化学
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产品关联
DOI
高影响因子
BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS
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2016
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IF 5.083
Lang-Hong Wang,Man-Sheng Wang,Xin-An Zeng,De-Ming Gong,Yan-Bo Huang
Background Some antibacterial agents exert their antimicrobial action by targeting the cytoplasmic macromolecules , such as proteins or nucleic acids , to disturb the properties of macromolecules that may deeply influence their biological activities and functions. Cinnamaldehyde (CIN) is a natural antibacterial ingredient found in the bark and leaves of cinnamon trees . Methods The inhibitory mechanism of a typical enzyme , β-galactosidase by CIN was investigated by UV–visible, fluorescence, 3-D spectroscopy, circular dichroism , atomic force microscopy and molecular modeling studies. Results CIN decreased the activity of β-galactosidase by competitive inhibition through a multiphase kinetic process. 3-D spectroscopy and circular dichroism showed that the binding of CIN to β-galactosidase resulted in changes in micro-environment of tryptophan and tyrosine residues, and conformation of β-galactosidase. The molecular recognition was also analyzed through modeling which indicated that CIN was inserted into the active site pocket of β-galactosidase and interacted with amino acid residues, such as Met502, Trp568, Phe601 and Trp999. Atomic force microscopy showed that a serious destabilization of the native conformation of β-galactosidase occurred after binding with CIN, e.g., morphological changes and increased dimensions of the β-galactosidase molecule. Moreover, it was found that the combinations of CIN, carvacrol and thymol exposure displayed synergistic effects on the inhibition of β-galactosidase. General significance This study exhibits a comprehensively understanding about the action mechanism of CIN that affects the conformation and activity of β-galactosidase in biochemical processes and provides some new insights into the possible intracellular targeting behaviors of CIN at a molecular level.
研究领域:
生物化学
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分子生物学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
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IF 2.5
Sisi Zhang,Weiping Liu,Sikai Wang,Lei Wang,Lin Lv,Yan Zhao
β-Galactosidase (β-Gal), alternatively referred to as lactase, is intricately associated with cellular aging and the progression of ovarian and breast cancers due to its aberrant activity. Therefore, the accurate detection of this enzyme holds substantial importance for early disease diagnosis. In this work, a sensitive ratiometric fluorescent sensing system utilizing silver nanoclusters (AgNCs) was developed for the first time to measure β-Gal activity. Specifically, β-Gal catalyzed the hydrolysis of its substrate 3-indoxyl-β-D-galactopyranoside, leading to the production of hydrogen peroxide (H2O2) and an indoxyl oxidation product that emitted blue fluorescence at 478 nm. The generated H2O2 effectively quenched the fluorescence of AgNCs at 627 nm. Thus, the fluorescence intensity ratio F478/F627 can be used for the detection of β-Gal activity. The results demonstrated that the ratio of F478/F627 exhibited excellent linear correlations with β-Gal activity within the ranges of 0.2-10.0 U/L and 10.0-50.0 U/L, achieving a detection limit of 0.031 U/L. Furthermore, the ratiometric fluorescent method was effectively utilized to measure β-Gal levels in human serum samples, highlighting its substantial potential for clinical diagnostics.
研究领域:
生物化学
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医学诊断
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分析化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Yongmei Lyu,Fengxiang Chen,Wanjie Mao,Zhihan Ge,Yaoyao Zhang,Yue Hu,Wenbin Jin,Jinbin Liu,Jia Chen,Xiaohong Yu,Xiaoyang Zhang
Lactose intolerance has been a significant global health concern, as it is caused by the absence of lactase, leading to the inability of the human body to absorb lactose. This study investigated two genes encoding maltose O -acetyltransferase with β-galactosidase activity from Aeromonas caviae to evaluate their potential application value for lactose degradation in bovine and human milk. The two novel β-galactosidases (AcGal25: 22.0 kDa and AcGal31: 21.3 kDa) were heterologously expressed and biochemically characterized. The optimal pH of both enzymes was 8.0, and the optimal temperature of AcGal25 and AcGal31 were 45 and 42 °C, respectively. Fe 2+ and Mn 2+ significantly promoted the activity of both enzymes. The two enzymes kept over 75 % activity after incubation for 30 days at 45 °C. HPLC results showed that lactose in bovine milk was completely hydrolyzed by AcGal31 when reacted for 6 h, and about 5 % lactose in human milk was left. The docking results showed that AcGal31 has a more vital lactose-binding ability than AcGal25. LYS129 and ARG165 are highly likely catalytic sites of AcGal31. AcGal31 demonstrated excellent commercial value in making lactose-free milk.
研究领域:
生物化学
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食品科学
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工业酶学
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产品关联
DOI
PubMed
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
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2025
·
IF 3.7
Wanwan Wang,Lei Wang,Rensong Sun,Hao Wu,Ziang Liu,Xiao Qian,Jiayu Quan,Engin U. Akkaya
Graphical β-Galactosidase-triggered release of singlet oxygen is shown to target and selectively eliminate senescent cells. In addition, data obtained using tumor models reveal a significant suppression of tumor progression by targeted singlet oxygen release. Targeting senescent cells for cancer treatment is an important recent direction. In this work, we designed and synthesized a galactoside-functionalized pyridone endoperoxide. The endoperoxide in this form, releases singlet oxygen at a relatively slow rate, but when transformed by β-galactosidase activity, the pyridone endoperoxide releases singlet oxygen with a half-life of 30 minutes at 37 °C. We also studied this compound with a variety of cell lines with differential β-galactosidase expression levels. Cytotoxicity of the target compound is enhanced in high galactosidase-expressing SKOV-3 cells. In vivo tests with tumor models also showed significant suppression of tumor progression. Targeting singlet oxygen to senescent cells appears to be promising new approach for treating diseases concurrent with aging, including cancer.
研究领域:
生物化学
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肿瘤学
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药物化学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2019
·Vol. 37
·期 4
·330-336
·
IF 2.376
Min Chen,Lixuan Mu,Xingxing Cao,Guangwei She,Wensheng Shi
Summary of main observation and conclusion β-Galactosidase, a glycoside hydrolase enzyme, has been proved to be an important biomarker of cell senescence and primary ovarian cancer. Effective detection of β-galactosidase has attracted wide attention. Herein, one ratiometric fluorescent probe has been successfully synthesized for detecting the β-galactosidase in living cells. The as-prepared probe exhibits two emission peaks at 490 nm and 530 nm, respectively, and the ratio of fluorescence intensities from the two emission peaks could be utilized to monitor the β-galactosidase. This present ratiometric fluorescent probe is, therefore, very promising for effective, sensitive, and selective detection of the β-galactosidase in living cells.
研究领域:
生物化学
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分子生物学
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医学诊断
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Qiaoli Yang,Yaping Wang
This research developed an electrochemical biosensor based on T4 bacteriophages assembled with beta-galactosidase (β-gal) for Escherichia coli K12 ( E. coli K12) detection. The β-gal Soc fusion proteins were affinity-assembled on the Hoc − Soc − T4 phage capsid, exhibiting superior substrate affinity and enhanced stability compared to the free enzyme. The antibodies were immobilized on the multiwalled carbon nanotube/gold nanoparticle modified electrode, and then the engineered β-gal T4 was bonded the bacterial cells captured by the antibodies, constructing the electrochemical biosensor. The biosensor can detect E. coli K12 as low as 6 CFU/mL within 90 mins utilizing catalytic events of β-gal T4. The biosensor exhibited high specificity, distinguishing live target bacteria from non-target bacteria or dead target bacteria, which is attributed to its dual recognition mechanism involving antibody and β-gal T4. The biosensing platform can be extended to other bacteria by customizing phage-enzyme combinations, enabling bacterial detection in food, environment and other fields.
研究领域:
微生物学
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生物传感技术
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分子生物学
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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）