INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2024
·Vol. 25
·期 3
·1533
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IF 4.9
Hongxuan Du,Yaoyao Liang,Jianing Li,Xinyao Yuan,Fenglin Tao,Chengjie Dong,Zekai Shen,Guangchao Sui,Pengchao Wang
Biosensors based on allosteric transcription factors have been widely used in synthetic biology. In this study, we utilized theAcinetobacterADP1 transcription factor PobR to develop a biosensor activating the PpobApromoter when bound to its natural ligand, 4-hydroxybenzoic acid (4HB). To screen for PobR mutants responsive to 4-hydroxyphenylpyruvate(HPP), we developed a dual selection system inE. coli. The positive selection of this system was used to enrich PobR mutants that identified the required ligands. The following negative selection eliminated or weakened PobR mutants that still responded to 4HB. Directed evolution of the PobR library resulted in a variant where PobRW177Rwas 5.1 times more reactive to 4-hydroxyphenylpyruvate than PobRWT. Overall, we developed an efficient dual selection system for directed evolution of biosensors.
研究领域:
合成生物学
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微生物学
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分子生物学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2025
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IF 6.2
Yihan Chen,Wanqing Wei,Jianhao Xu,Wei Song,Jian Wen,Guipeng Hu,Xiaomin Li,Cong Gao,Jing Wu
3-Hydroxy-3-methylbutyrate (HMB), an important dietary supplement, can enhance the quality of life for sedentary and elderly people. However, the catalytic efficiency of the pathway enzymes limited the biosynthesis of HMB. Here, we identified an efficient 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) from Bacteroides barnesiae (BbHPPD) that converted l-Leucine (l-Leu) to HMB together with an efficient L-amino acid deaminase (L-AAD) in lab-preserved Proteus mirabilis (PmL-AADQ92A). The regioselective hydroxylation mechanism of the decarboxylated intermediate of 4-methyl-2-oxopentanoic acid (α-KIC) catalyzed by BbHPPD was elucidated for the first time. Structure-guided semirational design of BbHPPD generated a mutant M4. Compared to the wild type, the titer of mutant M4 increased by 254% when using α-KIC as a substrate. Finally, the engineered Escherichia coli 06 strain achieved the HMB titer of 11.6 g/L, a molar conversion of 65%, and a space-time yield of 0.64 g/(L·h) (the highest to date) in 18 h. This study lays the foundation for industrial-scale biosynthesis of HMB.
研究领域:
生物化学
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合成生物学
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代谢工程
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PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2021
·
IF 5.279
Hao-Min Song,Li-Xia Zhao,Shuai-Qi Zhang,Tong Ye,Ying Fu,Fei Ye
Cinnamic acid, isolated from cinnamon bark, is a natural product with excellent bioactivity, and it effectively binds with cyclohexanedione to form novel 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors. According to the active sub-structure combination principle, a series of novel 3-hydroxy-2-cinnamoyl-2-en-1-one derivatives were designed and synthesized. The title compounds were characterized by infrared, 1H NMR, 13C NMR, and HRMS. The in vitro inhibitory activity of AtHPPD verified that compound II-13 showed the most activity with a half-maximal inhibitory concentration (IC50) value of 0.180 μM, which was superior to that of mesotrione (0.206 μM) in vitro. The preliminary herbicidal activity tests demonstrated that some compounds had good herbicidal activity especially compound II-13 at a concentration of 150 g ai/ha. The binding mode of AtHPPD through molecular docking indicated that two oxygens of compounds II-13 formed bidentate interactions with metal ions, and the benzene ring formed π-π accumulation effects with Phe-381 and Phe-424. The results of molecular dynamics simulations showed that compound II-13 exhibited a more stable binding ability with AtHPPD than mesotrione. This study provided insights into the development of natural and efficient herbicides in the future.
研究领域:
化学
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药理学
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农业科学
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分子生物学
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植物科学
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PubMed
高影响因子
Drug Metabolism and Pharmacokinetics
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2019
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IF 1.874
Yang Zhang,Chen Su,Jinxiu Lei,Lu Chen,Haihong Hu,Su Zeng,Lushan Yu
Mandelic acid (MA) is generally used as a biomarker of the exposure of styrene , which is classified as a class of hazardous environmental pollutants, and also used as an important chiral intermediate in pharmaceutical industry. The previous studies have found the excretion of phenylglyoxylic acid (PGA) in human and rat, a metabolite of MA, was mainly from S- MA rather than R -MA. The metabolic mechanism, however, is not clear. In order to explore the possible metabolic mechanism, the enzyme types involved in the stereoselectivity metabolism of MA were firstly studied, and then human and rat long-chain 2-hydroxy-acid oxidase 2 (HAO2) were recombinantly expressed to study the metabolic profiles of S- MA and its analogues. The results indicated that HAO2 might catalyze the stereoselectivity metabolism of S- MA in rats. Human HAO2 ( h HAO2) and rat HAO2 ( r HAO2) isozymes β 1 and β 2 were successfully cloned and expressed with high purity and good enzyme activities. The enzyme kinetic profiles of these enzymes were different for S- MA and analogues. The order of catalytic efficiency for h HAO2 and r HAO2, however, was reverse. It might be relevance to the difference in active amino acid residues and loop 4 in human and rat L-2-hydroxy acid oxidase isozyme B crystal structures.
研究领域:
环境科学
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生物化学
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毒理学
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药物化学
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PubMed
高影响因子
ANALYTICAL CHEMISTRY
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2024
·
IF 6.7
Zheng Li,Xiaohui Lu,Zhiyang Zhang,Shuoyang Yan,Yunli Yang
Phenylketonuria (PKU) is one of the most common genetic metabolic diseases, especially among newborns. Traditional clinical examination of newborn blood samples for PKU is invasive, laborious, and limited to hospitals and healthcare facilities. We reported herein a SERS-based sensor array with three thiophenolic nanoreceptors built on a patterned nanorod vertical array for rapid and inexpensive detection of characteristic volatile biomarkers indicative of PKU in the urine and accurate classification of newborn baby patients all performed on a hand-held SERS spectrophotometer. The well-ordered array was generated from the volatility-driven assembly of gold nanorods (AuNRs) into an upright and closely packed hexagonal configuration. The uniformly distributed nanowells between AuNRs offered an intense and aspect-ratio-dependent plasmonic field for the molecular enhancement of SERS outputs. The SERS-based detector was integrated into a test chip for regular monitoring of volatile phenylketone bodies in the spiked solution or patients’ urine within 5 min, allowing the quantification of a wide variety of normal or abnormal metabolites at their physiologically relevant concentration range. The detection limits for common biomarkers of PKU, including phenylpyruvic acid, 4-hydroxyphenylacetic acid, and phenylacetic acid, were at a few μM and well below the diagnostic thresholds. Moreover, the volatile headspace mixtures from a given urine sample could be fingerprinted by the sensor array and discriminated using machine-learning algorithms. Ultimately, the discrimination of baby patients among 26 cases of mild and classic PKU phenotypes and 17 cases of healthy volunteers could be realized with an overall accuracy of 97%. This hand-held SERS platform plays a pivotal role in advancing healthcare applications in quick screening of neonatal PKU through a facile urinary vapor test.
研究领域:
医学诊断
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分析化学
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纳米技术
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2023
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IF 6.1
Huidong Xu,Qianqian Cheng,Yangyu Qiu,Jingjing Mao,Qinyi Ji,Mulan Zhu,Lili Zhang,Zhouping Wang,Aitao Li,Yu Xia
l-Phenyllactic acid (l-PLA) is a small molecular organic acid that exhibits a powerful capacity for inhibition against foodborne pathogens. In this work, we developed a new cost-effective and environmentally friendly process for the biosynthesis of l-PLA. This strategy designed a novel whole-cell biotransformation system employing two heterologous enzymes, namely, phenylalanine dehydrogenase (PheDH) and l-hydroxyisocaproate dehydrogenase (l-HicDH). The novelty of this strategy lies in the first-time utilization of these two enzymes, which not only enables cascade catalysis for the production of l-PLA but also facilitates the regeneration of the coenzymes (NAD+/NADH) using only two enzymes rather than introducing more heterologous enzymes to the system. Consequently, this strategy can effectively simplify the biosynthesis process of l-PLA and minimize production costs. The initial l-PLA yield using this process achieved 2.53 ± 0.07 g/L. Furthermore, through meticulous optimization of the parameters for inducible enzyme expression and l-PLA biosynthesis, the l-PLA yield was successfully increased to 4.68 ± 0.04 g/L with a yield rate of 64.54 ± 0.29%. Moreover, this novel strategy is versatile in the biosynthesis of other organic acids, which can be achieved by easily modulating the combinations of substrates and enzymes.
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高影响因子
RSC Advances
·
2015
·Vol. 5
·期 60
·48885-48892
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IF 3.84
Hongkai Xie,Wenhua Ji,Dahui Liu,Wei Liu,Daijie Wang,Ruimin Lv,Xiao Wang
In this work, surface molecularly imprinted polymers with dummy templates were developed as the selective sorbents for preparation of dencichine from the extract of Panax notoginseng for the first time. The polymers were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The performances of molecularly imprinted and non-imprinted polymers were evaluated, which included selective recognition, adsorption isotherms and adsorption kinetics. Optimization of various parameters affecting molecularly imprinted solid phase extraction, such as sample loading pH and flow rate, the composition and volume of the eluting solvent and the composition and volume of the washing solvent were investigated. Compared with NISPE, MISPE displayed improved specific adsorption performance. Dencichine with a purity of 98.7% was obtained from the aqueous extract of Panax notoginseng with the average recovery of 83.7% (n = 3).
研究领域:
药物化学
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分析化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）