细胞色素P450酶代谢物的先导物研发

细胞色素P450(CYP)酶在药物代谢方面发挥着重要作用,它可以催化一些有机反应,生成一些具有新型药理活性的化学实体。本文主要从CYP参与大量天然产物的生物合成途径,及一些已知药物通过CYP参与的代谢后生成药理活性物质两个方面,介绍细胞色素P450酶代谢物的研发现状。

复方丹参滴丸对药物代谢酶CYP1A2活性的影响

目的:观察复方丹参滴丸对药物代谢酶CYP1A2活性的影响。方法:收集2016年6月到2018年2月42名受试者的尿液,利用(AFMU+1X+1U)/17 U比率法评价复方丹参滴丸对药物代谢酶CYP1A2活性的影响。结果:患者用药前的CYP1A2活性为(4.18±1.52),服药两周后的CYP1A2活性为(4.24±1.95),服药1个月后的CYP1A2活性为(4.33±1.24)。与用药前相比,受试者服药两周、1个月后的药物代谢酶CYP1A2活性没有显著变化。结论:复方丹参滴丸不会对物代谢酶CYP1A2活性产生明显影响。

化痰活血方对高脂血症大鼠肝脏过氧化物酶体增殖物激活受体α及其目标基因表达的影响

目的:观察化痰活血方对高脂血症大鼠肝脏过氧化物酶体增殖物激活受体α(PPARα)、乙酰辅酶A氧化酶(ACO)表达的影响。方法:建立高脂血症大鼠模型后分别给予化痰活血方大、中、小剂量及力平脂治疗,检测其相关指标。结果:化痰活血方能显著降低高脂血症大鼠血清总胆固醇(TC)、甘油三酯(TG)的水平,增强肝脏PPARα、ACO mRNA的表达。结论:化痰活血方增强PPARα、ACO mRNA的表达可能是其治疗高脂血症的分子机制之一。

药物代谢酶在药物合用中的重要性分析

目的探讨药物代谢酶在药物合用中的重要性。方法选择2016年6月~2018年2月42例受试患者,对其服用复方丹参滴丸联合人肝脏药物,利用(AFMU+1X+1U)/17U比率法评价复方丹参滴丸对药物代谢酶CYP1A2活性的影响;同时使用反相高效液相色谱法检测患者服药前后尿液内咖啡因4种主要代谢产物的含量。结果患者用药前的CYP1A2活性为(4.18±1.52),服药两周后的CYP1A2活性为(4.24±1.95),服药1个月后的CYP1A2活性为(4.33±1.24)。结论复方丹参滴丸不会对物代谢酶CYP1A2活性产生影响作用。

Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Seeds under Different Temperatures

[Objective] To study the germination characteristics and secondary metabolism of Scutellaria baicalensis Georgi seeds under different temperatures.[Method]The activities of superoxide dismutase（SOD）and peroxidase（POD）were determined with lactoflavine-NBT method and guaiacol-colorimetry assay,respectively.The catalase（CAT）,ascorbate peroxidase（APX）,phenylalanine ammonia-lyase（PAL）and cinnamic acid 4-Hydroxylase（C4H）were determined with ultraviolet spectrophotometry.The secondary metabolites were detected by High Performance Liquid Chromatography（HPLC）.[Result]The germination percentage,germination potentiality and germination index were seriously affected by low or high temperature.The proper germination temperature was 20-25 ℃.The activities of SOD,POD and CAT were significantly decreased as comparison to suitable temperature.The activities of PAL and C4H were also significantly decreased as comparision to suitable temperature which was accordance to the secondary metabolites.There was a positive correlation between the flavonoids content and the PAL and C4H activity（r=0.956,r=0.951,P0.05）.[Conclusion]The quality of the skullcaps could be improved by improving the activity of PAL and C4H.The proper temperature for the seed germination and the formation of secondary metabolites was 20 ℃.

Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi Seeds under Different Light Intensities

[Objective] This study aimed to investigate the primary and secondary metabolisms during the germination of Scutellaria baicalensis Georgi seeds under different light intensities. [Method] The activities of CHL, soluble sugar, PAL, C4H and CHS were determined with ultraviolet spectrophotometry. The secondary metabolites were detected by High Performance Liquid Chromatography （HPLC）. [Result] The results indicate that the germination of Scutellaria baicalensis Georgi seeds is not sensitive to light and the seedlings were very sensitive to light. The CHL, soluble sugar, PAL, C4H and CHS continuously increased with light intensity. The content of secondary metabolites also increased. [Conclusion] Light increased the formation of leaf photosynthetic pigment, thereby affecting the primary metabolites. The activities of PAL, C4H and CHS significantly increased with the development of light intensity. Finally the secondary metabolites of medicinal plants increased sharply. Therefore, the quality of Scutellaria baicalensis Georgi materials can be improved by increasing the light intensity moderately.

Changes of Primary and Secondary Metabolism during the Seed Germination of Scutellaria baicalensis Georgi

[Objective] To investigate the primary and secondary metabolism during the seed germination of Scutellaria baicalensis Georgi. [Method] The activities of SOD and POD were determined with lactoflavine-NBT method and guaiacol-colorimetry as- say, respectively. The activities of CAT, APX,PAL and C4H were determined with ultraviolet spectrophotometry. The contents of secondary metabolites were detected by High-performance Liquid Chromatography （HPLC）. [Result] The results indicate that the soluble sugar content decreased during the first 5 days and then increased when the cotyledons formed. The contents of PAL, C4H and CHS continuously in- creased at different stages during the seed germination process. The secondary metabolites also showed the consistent variation trend. In addition, the contents of secondary metabolites had significant positive correlation with the key enzyme activi- ty. [Conclusion] The formation of secondary metabolites is significantly positively cor- related with the key enzyme during the seed germination process. Therefore, the key enzyme activity can be enhanced by adopting appropriate measures to improve the secondary metabolites, thereby obtaining high-quality medicinal materials.

Expression of Recombinant Tryptophan Decarboxylase in Different Subcellular Compartments in Tobacco Plant

The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.

Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi under Different Illumination Time

This study aimed to investigate the primary and secondary metabolism of Scutel aria baicalensis Georgi during seed germination process under different il umination time. [Method] Chlorophyl （CHL） content, soluble sugar content, phenylalanine ammonia lyase （PAL） activity and cinnamate-4-hydroxylase （C4H） ac-tivity were determined with ultraviolet spectrophotometry. The secondary metabolites were detected by high performance liquid chromatography （HPLC）. [Result] The re-sults indicated that the germination of S. baicalensis seeds was not sensitive to light and the seedlings were very sensitive to light. CHL content, soluble sugar content, PAL activity and C4H activity increased continuously with the il umination time. The secondary metabolites showed a similar trend. [Conclusion] Il umination time promoted the formation of leaf photosynthetic pigments, thereby affecting the synthesis of primary and secondary metabolites and the activities of PAL and C4H. Therefore, the quality of S. baicalensis can be improved by regulating the il umina-tion time appropriately.

Advancements in biocatalysis:From computational to metabolic engineering

Through several waves of technological research and un‐matched innovation strategies,bio‐catalysis has been widely used at the industrial level.Because of the value of enzymes,methods for producing value‐added compounds and industrially‐relevant fine chemicals through biological methods have been developed.A broad spectrum of numerous biochemical pathways is catalyzed by enzymes,including enzymes that have not been identified.However,low catalytic efficacy,low stability,inhibition by non‐cognate substrates,and intolerance to the harsh reaction conditions required for some chemical processes are considered as major limitations in applied bio‐catalysis.Thus,the development of green catalysts with multi‐catalytic features along with higher efficacy and induced stability are important for bio‐catalysis.Implementation of computational science with metabolic engineering,synthetic biology,and machine learning routes offers novel alternatives for engineering novel catalysts.Here,we describe the role of synthetic biology and metabolic engineering in catalysis.Machine learning algorithms for catalysis and the choice of an algorithm for predicting protein‐ligand interactions are discussed.The importance of molecular docking in predicting binding and catalytic functions is reviewed.Finally,we describe future challenges and perspectives.

Fatty Acid Synthase Inhibitors from Plants and Their Potential Application in the Prevention of Metabolic Syndrome

Fatty acid synthase （FAS） attracts more and more attention recently as a potential target for metabolic syndrome,such as cancer, obesity, diabetes and cerebrovascular disease. FAS inhibitors are widely existed in plants, consisting of diversiform compounds. These inhibitors exist not only in herbs also in many plant foods, such as teas, allium vegetables and some fruits. These effective components include gallated catechins, theaflavins,flavonoids, condensed and hydrolysable tannins, thioethers,pentacyclic triterpenes, stilbene derivatives, etc, and they target at the different domains of FAS, showing different inhibitory mechanisms. Interestingly, these FAS inhibitor-contained herbs and plant foods and their effective components are commonly related to the prevention of metabolic syndromes including fatreducing and depression of cancer. From biochemical angle,FAS can control the balance between energy provision and fat production. Some studies have shown that the effects of those effective components in plants on metabolic syndromes are mediated by inhibiting FAS. This suggests that FAS plays a critical role in the regulation of energy metabolism, and the FAS inhibitors from plants have significant potential application value in the treatment and prevention of metabolic syndromes.

Effect of superoxide dismutase and malondialdehyde metabolic changes on carcinogenesis of gastric carcinoma

AIM： To investigate the relationship between the superoxide dismutase （SOD）, malondialdehyde （MDA） metabolic changes and the gastric carcinogenesis.METHODS： The SOD activity and MDA content were measured in the gastric tissues from the focus center, peripheral and far-end areas of gastric carcinoma （n = 52） arid gastric ulcer （n = 10）. All the tissues were subjected to routine histological examinations and classifications.RESULTS： The SOD activity was greatly reduced but the MDA content was markedly increased in the center areas of the non-mucous gastric carcinoma （non-MGC）; and the poorly differentiated gastric carcinoma varied. The SOD activity was gradually decreased and the MDA content was gradually increased in the tissues from the focus far-end, peripheral to center areas of non-MGC. Both of the SOD activity and the MDA content were significantly declined and were respectively at same low level in the tissues from the focus center, peripheral, and far-end area with the mucous gastric carcinoma （MGC）. In contrast to the gastric ulcer and grade I or II of non-MGC, the same level of the SOD activity and the MDA content were found in the focus center areas. Between non-MGC （groups A-D） and gastric ulcer （group F）, the differences of SOD activity and MDA content were very noticeable in the gastric tissues from the focus peripheral and far-end areas, in which the SOD activity showed noticeable increase and the MDA content showed noticeable decreasein the gastric ulcer.CONCLUSION： The active free radical reaction in the gastric tissues can induce the carcinogenesis of non-MGC. The utmost low ability of antioxidation in the gastric tissues can induce the carcinogenesis of MGC. The metabolic change of the free radicals centralized mostly in the center of ulcerated lesions only, which suggested the ability of antioxidation was declined only in these lesions. However, the metabolism of free radicals varied significantly and the ability of antioxidation declined not only in the local focus area but also in the abroad gastric tissues with gastric carcinoma.

Phytogenic Feed Additive for Sows： Effects on Sow Feed Intake, Serum Metabolite Concentrations, IgG Level, Lysozyme Activity and Milk Quality

The objective of this study was to investigate the influence ofa phytogenic feed additive （PFA） to late-gestation （d 90） and lactation sows on their reproduction performance. Sixty Large White × Landrace primiparous sows were divided into four groups （fifteen sows per group）. The control group was fed with basal diet, the others were fed with basal diet supplemented with 0.02%, 0.04% and 0.06% PFA, respectively. Compared with the control, the sows in 0.04% PFA group had higher feed intake during lactation and higher litter weaning weight （P 〈 0.05）. At farrowing, glucose level in 0.04% PFA sows was higher than the control and sows in 0.02% PFA had the highest IgG content among the treatments （P 〈 0.05）. On day 7 of lactation, serum urea nitrogen contents were lower in response to PFA supplementation compared to the control （P 〈 0.05）. At the same time, sows fed the 0.06% PFA diet increased the lysozyme activity （P 〈 0.05）. The levels of milk lactose and IgG were increased in 0.02% and 0.04% PFA groups （P 〈 0.05）. In conclusion, feeding PFA improved sows and litter performance, serum metabolite concentrations, lgG level and lysozyme activity at postpartum and milk quality.

Research Progress in Plant Invertase

Invertase is a key enzyme in sucrose catabolism and crucial for plant assimilate distribution. With the development of molecularbiology, a lot of invertsae genes were cloned recently, and significant progress have been made in regulators on the expression of invertase genes.Thus, this article summarized theresearch progress of invertase in biological characteristics, molecular characteristics and expression regulation.

Manila clam Venerupis philippinarum as a biomonitor to metal pollution

The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the Bohai Sea; however, little attention has been paid to potential biological differences between these two pedigrees. In this study, we tested the sensitivity of both pedigrees to marine metal (cadmium and zinc) pollution biomonitoring and marine environmental toxicology. Results demonstrate significant biological differences in gills of white and zebra clams based on metabolic profiles and antioxidant enzyme activities. In addition, we found that hypotaurine, malonate and homarine were relatively high in white clam gills, while alanine, arginine, glutamate, succinate, 4-aminobutyrate, taurine and betaine were high in zebra clam gills. Zebra clam gills were also more sensitive to a mixture of Cd and Zn, as shown by antioxidant enzyme activities and metabolic profiles, but white clam gills could accumulate more Zn. Therefore, we suggest that the white pedigree can be used as a biomonitor to marine Zn pollution, whereas the zebra pedigree can be used for toxicology studies on Cd and Zn mixed pollution.

A Population Morphologically Structured Model for Microscopic Growth of Filamentous Microorganism

The growth of filamentous microorganism is contributed by tip extension and branching. The microscopic growth of filamentous microorganism means the growth process from one or a few spores. In order to describe the microscopic process, a population morphologically structured model is proposed, in which three morphological compartment and their interactions were considered, and the heterogeneity of hyphal growth was included. The model was applied to describe the microscopic growth of Streptomyces tendae and Geotrichum candidum with good agreement. From model prediction, it is concluded that if the number of hyphae is large enough (macroscopic growth), the specific growth rate of filamentous microorganism and the ratio of morphological forms in hyphae will become constant.

Construction and Expression of Sugarcane UGPase cDNA Prokaryotic Expression Vector

UGPase （UDP-glucose pyrophosphorylase）, one of the primary enzymes concerned with carbohydrate metabolism, catalyzes the formation of UDPG. By inserting the UGPase cDNA fragment cloned from Saccharum officinarum into PQE-30, the prokaryotic expression vector of PQE-UGP was successfully constructed. Then the vector plasmid of PQE-UGP was transformed into host bacteria M 15 and the expression of target gene was induced by Isopropyl β-D-1-Thiogalactopyranoside （IPTG）. The research laid foundation for study on the prokaryotic expression of UGPase.

Cloning of ACC Oxidase （ACO） Gene from Dendrobium officinale

Many studies suggest that ethylene plays an important role in regulating metabolite synthesis. Dendrobium plants are traditional Chinese medicine and nowadays its medicinal components are known to be secondary metabolites. In present study, a homolog of ACC oxidase （ACO） gene was isolated from flowers of Dendrobium officinale Kimura et Migo by PCR-method. The obtained cDNA of DoACO is 970 bp long and contains an open reading frame （ORP） encoding a protein with 314 amino acid residues. The DoACO shows high identity to its homologues from other plant species, that has 94.8% closest amino acid sequence of related protein with the ACO from Dendrobium hybrid cultivar. The putative ORP of the obtained sequence could encode a proper protein in respect of molecular weight under T -Lac promoter in E. coli.

Recent advance in SNP identifying methods and individualized medication

Polymorphisms associated with genes coding for a variety of drug-metabolizing enzymes （DMEs） and associated transport proteins can influence the drug metabolism rate of individuals, potentially affecting the efficacy of drug and the occurrence of adverse reactions. Single nucleotide polymorphisms （SNPs） are prevalent in all types of genetic variations. Reliable SNP genotyping provides excellent markers for detecting genetic polymolphisms, genetic disorders, and resistance of pathogen to drug, which are needed for the genetic diagnosis of disease and subtle genetic factors. With a large number of SNP genotyping studies being conducted, a lot of novel SNP identifying methods have been developed. Several SNP genotyping methods and techniques have been introduced for clinical test. These include TaqMan drug metabolism genotyping assays, pH-sensing semiconductor system, high-resolution melting curve analysis （HRM） of polymerase chain reaction （PCR） amplicons, novel multiplexed electrochemical biosensor with non-fouling surface, DNA hybridization detection using less than 10-nm gap silicon nanogap structure, tetra-primer ARMS-PCR method, acoustic detection of DNA conformation in genetic assays combined with PCR, microbeads-mass spectrometry （MEMS）-based approach, and liquid chromatography-electrospray ionization mass spectrometry. Personalized medicine has changed the conventional ways of using drugs according to experiences. It focuses on making the individualized pattern for each individual based on their own characteristics. Lots of researchers are using the analysis of clinical samples to explain the relationship between the drug adverse reactions and genetic polymorphisms. But it takes a long time from collecting the blood samples for DNA extraction and genotyping to getting results on the side effect of drug through clinical study. Therefore, it is desirable to develop improved in vitro methods to study the drug metabolizing-enzymes and transport protein genetic polymorphisms.