The present study aimed to investigate the composition of the terpene synthase(TPS) gene family in Gynostemma pentaphyllum and its role in abiotic stresses. The G. pentaphyllum TPS gene family was identified and analyzed at the genome-wide level using bioinformatics analysis, and the expression patterns of these family members were analyzed in different tissues of G. pentaphyllum as well as under various abiotic stresses. The results showed that there were 24 TPS gene family members in G. pentaphyllum with protein lengths ranging from 294 to 842 aa. All of them were localized in the cytoplasm or chloroplasts and unevenly distributed on the 11 chromosomes of G. pentaphyllum. The results of the phylogenetic tree showed that the G. pentaphyllum TPS gene family members could be divided into five subfamilies. As revealed by the analysis of promoter cis-acting elements, TPS gene family members in G. pentaphyllum were predicted to respond to a variety of abiotic stresses such as salt, low temperature, and dark stress. The analysis of gene expression patterns in different tissues of G. pentaphyllum revealed that nine TPS genes were tissue-specific in expression. The qPCR results showed that GpTPS16, GpTPS17, and GpTPS21 responded to a variety of abiotic stresses. This study is expected to provide references in guiding the further exploration of the biological functions of G. pentaphyllum TPS genes under abiotic stresses.
Gynostemma ; Phylogeny ; Alkyl and Aryl Transferases ; Chloroplasts

Cinnamomum camphora is an important economic tree species in China. According to the type and content of main components in the volatile oil of leaf, C. camphora were divided into five chemotypes, including borneol-type, camphor-type, linalool-type, cineole-type, and nerolidol-type. Terpene synthase(TPS) is the key enzyme for the formation of these compounds. Although several key enzyme genes have been identified, the biosynthetic pathway of(+)-borneol, which has the most economic value, has not been reported. In this study, nine terpenoid synthase genes CcTPS1-CcTPS9 were cloned through transcriptome analysis of four chemical-type leaves. After the recombinant protein was induced by Escherichia coli, geranyl pyrophosphate(GPP) and farnesyl pyrophosphate(FPP) were used as substrates for enzymatic reaction, respectively. Both CcTPS1 and CcTPS9 could catalyze GPP to produce bornyl pyrophosphate, which could be hydrolyzed by phosphohydrolase to obtain(+)-borneol, and the product of(+)-borneol accounted for 0.4% and 89.3%, respectively. Both CcTPS3 and CcTPS6 could catalyze GPP to generate a single product linalool, and CcTPS6 could also react with FPP to generate nerolidol. CcTPS8 reacted with GPP to produce 1,8-cineol(30.71%). Nine terpene synthases produced 9 monoterpene and 6 sesquiterpenes. The study has identified the key enzyme genes responsible for borneol biosynthesis in C. camphora for the first time, laying a foundation for further elucidating the molecular mechanism of chemical type formation and cultivating new varieties of borneol with high yield by using bioengineering technology.
Cinnamomum camphora/enzymology* ; Alkyl and Aryl Transferases/chemistry*

L-methionine, also known as L-aminomethane, is one of the eight essential amino acids required by the human body and has important applications in the fields of feed, medicine, and food. In this study, an L-methionine high-yielding strain was constructed using a modular metabolic engineering strategy based on the M2 strain (Escherichia coli W3110 ΔIJAHFEBC/PAM) previously constructed in our laboratory. Firstly, the production of one-carbon module methyl donors was enhanced by overexpression of methylenetetrahydrofolate reductase (methylenetetrahydrofolate reductase, MetF) and screening of hydroxymethyltransferase (GlyA) from different sources, optimizing the one-carbon module. Subsequently, cysteamine lyase (hydroxymethyltransferase, MalY) and cysteine internal transporter gene (fliY) were overexpressed to improve the supply of L-homocysteine and L-cysteine, two precursors of the one-carbon module. The production of L-methionine in shake flask fermentation was increased from 2.8 g/L to 4.05 g/L, and up to 18.26 g/L in a 5 L fermenter. The results indicate that the one carbon module has a significant impact on the biosynthesis of L-methionine, and efficient biosynthesis of L-methionine can be achieved through optimizing the one carbon module. This study may facilitate further improvement of microbial fermentation production of L-methionine.
Humans ; Methionine ; Methylenetetrahydrofolate Reductase (NADPH2) ; Carbon ; Cysteine ; Escherichia coli/genetics* ; Hydroxymethyl and Formyl Transferases ; Carrier Proteins ; Escherichia coli Proteins

Genome mining for the search and discovery of two new globin-like enzymes, TriB fromFusarium poae and TutaA from Schizophyllum commne, are involved in the synthesis of two linear terpenes tricinonoic acid (1) and 2-butenedioic acid (3). Both in vivo heterologous biosynthesis and in vitro biochemical assays showed that these two enzymes catalyzed the C-C double bond cleavage of a cyclic sesquiterpene precursor (-)-germacrene D (7) and a linear diterpene backbone schizostain (2), respectively. Our work presents an unusual formation mechanism of linear terpenes from fungi and expands the functional skills of globin-like enzymes in the synthesis of terpene compounds.
Terpenes/chemistry* ; Alkyl and Aryl Transferases ; Globins ; Diterpenes

Triterpenoids are one of the most diverse compounds in plant metabolites, and they have a wide variety of physiological activities and are of important economic value. Oxidosqualene cyclases catalyze the cyclization of 2, 3-oxidosqualene to generate different types of sterols and plant triterpenoids, which is of great significance to the structural diversity of natural products. However, the mechanism of the diversified cyclization of 2, 3-oxidosqualene catalyzed by oxidosqualene cyclases remains unclear. This review summarized the research progress of oxidosqualene cyclases from the aspects of catalytic function, molecular evolutionary relationship between genes and proteins, protein structure, molecular simulation and molecular calculations, which may provide a reference for protein engineering and metabolic engineering of triterpene cyclase.
Intramolecular Transferases/metabolism* ; Metabolic Engineering ; Plants/genetics* ; Squalene/chemistry* ; Triterpenes

Dipsaci Radix is one of the commonly used Chinese medicinal materials in China, with a long history. It has the medicinal activities of nourishing liver and kidney, recovering from broken sinews, and treating bone fracture. Triterpenoid saponins are the main functional ingredients of Dipsacus asper. β-Amyrin synthases(β-AS) as a superfamily of oxidosqualene cyclases(OSCs) can catalyze the construction of the skeleton structure of oleanane-type triterpenoid saponins. There are only a few studies about the β-AS in D. asper, and the catalytic mechanism of this enzyme remains to be explored. To enrich the information of β-AS, according to the transcriptome sequencing results, we cloned DaWβ-AS gene from D. asper into a specific vector for heterologous expression in Escherichia coli. In the meantime, real-time PCR was performed to analyze the relative expression of DaWβ-AS in four different tissues of D. asper. The results of RT-qPCR showed DaWβ-AS had the highest expression level in leaves. Bioinformatics results indicated that DaWβ-AS had a conserved domain of PLN03012 superfamily, belonging to the cl31551 superfamily. There was no transmembrane domain or signal peptide in DaWβ-AS. This study provides a scientific basis for revealing the biological pathways of triterpenoid saponins in D. asper, which will facilitate the biosynthesis of the associated saponins and afford reference for the cultivation and development of high-quality resources of D. asper.
Cloning, Molecular ; Computational Biology ; Dipsacaceae/chemistry* ; Intramolecular Transferases ; Protein Sorting Signals ; Saponins/chemistry* ; Triterpenes/chemistry*

This study cloned the transcription factor gene PnbHLH which held an open reading frame of 966 bp encoding 321 amino acids. This study constructed the overexpression vector of transcription factor PnbHLH of Panax notoginseng. The combination of PnbHLH overexpression and RNAi of the key enzyme gene PnCAS involved in the phytosterol biosynthesis was achieved in P. notoginseng cells, thus exploring the biosynthetic regulation of P. notoginseng saponins(PNS) by the synergistic effect of PnbHLH overexpression and PnCAS RNAi. The results showed that the PnbHLH transcription factor interacted with the promoters of key enzyme genes PnDS, PnSS and PnSE in the biosynthetic pathway of PNS, and then regulated the expression levels of key enzyme genes and affected the biosynthesis of saponins indirectly. Further study indicated that the synergistic effect of PnbHLH overexpression and PnCAS RNAi was a more effective approach to regulate the biosynthesis of saponins. Compared with the wild type and PnCAS RNAi cells of P. notoginseng, the contents of total saponins and monomeric saponins(Rd, Rb_1, Re, Rg_1 and R_1) were increased to some extent in the cell lines of PnbHLH overexpression and PnCAS RNAi. This indicated that the two ways of forward regulation and reverse regulation of saponin biosynthesis showed superposition effect. This study explored a more rational and efficient regulation strategy of PNS biosynthesis based on the advantages of multi-point regulation of transcription factors as well as the down-regulation of by-product synthesis of saponins.
Intramolecular Transferases ; Panax notoginseng ; RNA Interference ; Saponins ; Transcription Factors/genetics*

PURPOSE: The incidence of drug-induced liver injury (DILI) has been increasing; however, few algorithms are available to identify DILI in electronic health records (EHRs). We aimed to identify and evaluate DILI with an appropriate screening algorithm.METHODS: We collected data from 3 university hospitals between June 2015 and May 2016 using our newly developed algorithm for identifying DILI. Among patients with alanine transferase (ALT) ≤ 120 IU/L and total bilirubin (TB) ≤ 2.4 mg/dL in blood test results within 48 hours of admission, those who either had 1) ALT > 120 IU/L and TB > 2.4 mg/dL or 2) ALT > 200 IU/L at least once during hospitalization were identified. After excluding patients with liver disease-related diagnosis at discharge, medical records were retrospectively reviewed to evaluate epidemiological characteristics of DILI.RESULTS: The total number of inpatients was 256,598, of whom 1,100 (0.43%) were selected by the algorithm as suspected DILI. Subsequently, 365 cases (0.14% of total inpatients, 95% confidence interval, 0.13–0.16) were identified as DILI, yielding a positive predictive value of 33.1%. Antibiotics (n = 214, 47.2%) were the major class of causative drug followed by chemotherapeutic agents (n = 87, 19.2%). The most common causative drug was piperacillin-tazobactam (n = 38, 8.4%); the incidence of DILI by individual agent was highest for methotrexate (19.4 cases/1,000 patients administered the drug). Common reasons for excluding suspected DILI cases were ischemic hepatitis and postoperative liver dysfunction.CONCLUSIONS: Using our EHR-based algorithm, we identified that approximately 0.14% of patients developed DILI during hospitalization. Further studies are needed to modify criteria for more accurate identification of DILI.
Alanine ; Anti-Bacterial Agents ; Bilirubin ; Diagnosis ; Drug-Induced Liver Injury ; Drug-Related Side Effects and Adverse Reactions ; Electronic Health Records ; Hematologic Tests ; Hepatitis ; Hospitalization ; Hospitals, University ; Humans ; Incidence ; Inpatients ; Liver ; Liver Diseases ; Mass Screening ; Medical Records ; Methotrexate ; Pharmacoepidemiology ; Retrospective Studies ; Transferases

1-deoxy-D-xylulose-5-phosphate synthase2(DXS2) is the first key enzyme of the MEP pathway,which plays an important role in terpene biosynthesis of plants. According to the data of Swertia mussotii transcriptome, DXS2 gene(Gen Bank number MH535905) was cloned and named as Sm DXS2. The bioinformatics results showed that Sm DXS2 has no intron,with a 2 145 bp open reading frame encoding a polypeptide of 714 amino acids. They are belonging to 20 kinds of amino acids,and the most abundant amino acids include Ala,Gly and Trp. The predicted protein molecular weight was 76. 91 k Da and its theoretical isoelectric point(p I) was6. 5,which belonging to a hydrophilic protein. α-Helix and loop were the major motifs of predicted secondary structure of DXS2. The three function domains are TPP＿superfamily,Transket＿pyr＿ superfamily and Transketolase＿C superfamily,respectively. The Sm DXS2 protein shared high identity with other DXS2 proteins of plants. Phylogenetic analysis showed that Sm DXS2 protein is grouped with the gentian DXS2 protein. The recombinant protein of Sm DXS2 gene in Escherichia coli was approximately 92. 00 k Da(containing sumo-His tag protein 13 k Da),which was consistent with the anticipated size.This work will provide a foundation for further functional research of Sm DXS2 protein and increasing the product of iridoid compound by genetic engineering in S. mussotii.
Amino Acid Sequence ; Cloning, Molecular ; DNA, Complementary ; genetics ; Genes, Plant ; Iridoids ; Phylogeny ; Plant Proteins ; genetics ; Swertia ; enzymology ; genetics ; Transcriptome ; Transferases ; genetics

This study investigated advantages and potential risks associated with drinking alcohol in Koreans based on the alcohol flush reaction. Our investigation reviewed published studies and examined moderate-drinking levels for Koreans based on modified National Institute on Alcohol Abuse and Alcoholism guidelines. Fourteen articles out of a total 198 publications were searched using PubMed, EMBASE, KoreaMed, and RISS (Research Information Sharing Service) databases and selected for review. Individuals without alcohol flush reaction (non-flushers) exhibited lower risks associated with insulin resistance, metabolic syndrome, and hyperhomocysteinemia and their 10-year cardiovascular disease risk when alcohol consumption was ≤8 drinks/wk. Conversely, risks associated with insulin resistance, metabolic syndrome, high blood pressure, prediabetes or type-2 diabetes, and high intraocular pressure and increases in carbohydrate-deficient transferrin, gamma glutamyl transferase, and blood glucose levels were present when >8 drinks were consumed. For individuals with flushing reaction (flushers), advantages were reported in relation to risks of hyperhomocysteinemia when alcohol consumption was ≤4 drinks/wk, whereas consumption of >4 drinks/wk increased the risk of insulin resistance, metabolic syndrome, high blood pressure, pre-diabetes or type-2 diabetes, high-risk colorectal adenoma, and high intraocular pressure and increased carbohydrate-deficient transferrin, gamma glutamyl transferase, and blood glucose levels. The moderate drinking level for Koreans is ≤8 drinks/wk for men aged ≤65 years and ≤4 drinks/wk for men aged over 65. For women, these limits should be half of those for men. Furthermore, individuals with flushing reaction should maintain an alcohol consumption level half of that for non-flushers.
Adenoma ; Alcohol Drinking ; Blood Glucose ; Cardiovascular Diseases ; Drinking ; Female ; Flushing ; Humans ; Hyperhomocysteinemia ; Hypertension ; Information Dissemination ; Insulin Resistance ; Intraocular Pressure ; Male ; National Institute on Alcohol Abuse and Alcoholism (U.S.) ; Prediabetic State ; Transferases ; Transferrin