This study aims to investigate the mechanism of Qingrun Decoction in alleviating hepatic insulin resistance in type 2 diabetes mellitus(T2DM) rats through the reprogramming of amino acid metabolism. A T2DM rat model was established by inducing insulin resistance through a high-fat diet combined with intraperitoneal injection of streptozotocin. The model rats were randomly divided into five groups: model group, high-, medium-, and low-dose Qingrun Decoction groups, and metformin group. A normal control group was also established. The rats in the normal and model groups received 10 mL·kg~(-1) distilled water daily by gavage. The metformin group received 150 mg·kg~(-1) metformin suspension by gavage, and the Qingrun Decoction groups received 11.2, 5.6, and 2.8 g·kg~(-1) Qingrun Decoction by gavage for 8 weeks. Blood lipid levels were measured in different groups of rats. Pathological damage in rat liver tissue was assessed by hematoxylin-eosin(HE) staining and oil red O staining. Transcriptome sequencing and untargeted metabolomics were performed on rat liver and serum samples, integrated with bioinformatics analyses. Key metabolites(branched-chain amino acids, BCAAs), amino acid transporters, amino acid metabolites, critical enzymes for amino acid metabolism, resistin, adiponectin(ADPN), and mammalian target of rapamycin(mTOR) pathway-related molecules were quantified using quantitative real-time polymerase chain reaction(qRT-PCR), Western blot, and enzyme-linked immunosorbent assay(ELISA). The results showed that compared with the normal group, the model group had significantly increased serum levels of total cholesterol(TC), triglycerides(TG), low-density lipoprotein cholesterol(LDL-C), and resistin and significantly decreased ADPN levels. Hepatocytes in the model group exhibited loose arrangement, significant lipid accumulation, fatty degeneration, and pronounced inflammatory cell infiltration. In liver tissue, the mRNA transcriptional levels of solute carrier family 7 member 2(Slc7a2), solute carrier family 38 member 2(Slc38a2), solute carrier family 38 member 4(Slc38a4), and arginase(ARG) were significantly downregulated, while the mRNA transcriptional levels of solute carrier family 1 member 4(Slc1a4), solute carrier family 16 member 1(Slc16a1), and methionine adenosyltransferase(MAT) were upregulated. Furthermore, the mRNA transcription and protein expression levels of branched-chain α-keto acid dehydrogenase E1α(BCKDHA) and DEP domain-containing mTOR-interacting protein(DEPTOR) were downregulated, while mRNA transcription and protein expression levels of mTOR, as well as ribosomal protein S6 kinase 1(S6K1), were upregulated. The levels of BCAAs and S-adenosyl-L-methionine(SAM) were elevated. The serum level of 6-hydroxymelatonin was significantly reduced, while imidazole-4-one-5-propionic acid and N-(5-phospho-D-ribosyl)anthranilic acid levels were significantly increased. Compared with the model group, Qingrun Decoction significantly reduced blood lipid and resistin levels while increasing ADPN levels. Hepatocytes had improved morphology with reduced inflammatory cells, and fatty degeneration and lipid deposition were alleviated. Differentially expressed genes and differential metabolites were mainly enriched in amino acid metabolic pathways. The expression levels of Slc7a2, Slc38a2, Slc38a4, and ARG in the liver tissue were significantly upregulated, while Slc1a4, Slc16a1, and MAT expression levels were significantly downregulated. BCKDHA and DEPTOR expression levels were upregulated, while mTOR and S6K1 expression levels were downregulated. Additionally, the levels of BCAAs and SAM were significantly decreased. The serum level of 6-hydroxymelatonin was increased, while those of imidazole-4-one-5-propionic acid and N-(5-phospho-D-ribosyl)anthranilic acid were decreased. In summary, Qingrun Decoction may improve amino acid metabolism reprogramming, inhibit mTOR pathway activation, alleviate insulin resistance in the liver, and mitigate pathological damage of liver tissue in T2DM rats by downregulating hepatic BCAAs and SAM and regulating key enzymes involved in amino acid metabolism, such as BCKDHA, ARG, and MAT, as well as amino acid metabolites and transporters.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Rats ; Insulin Resistance ; Diabetes Mellitus, Type 2/genetics* ; Male ; Liver/drug effects* ; Amino Acids/metabolism* ; Rats, Sprague-Dawley ; Humans ; Metabolic Reprogramming

Hydroxyectoine, a vital compatible solute, is widely utilized in cosmetics, food, pharmaceutical industries, and biologics. However, the current microbial fermentation methods for hydroxyectoine production face challenges including insufficient precursor supply and low yields. Therefore, developing engineering microbial strains capable of efficiently synthesizing hydroxyectoine is of great significance. In this study, we first constructed a high-yield ectoine-producing strain ECT04 by multi-copy integration of the ectoine synthesis genes ectABC into the pseudogene loci of Escherichia coli MG1655(DE3), achieving an ectoine titer of 6.03 g/L. Subsequently, we employed plasmids with varying copy numbers to express ectD from Chromohalobacter salexigens to enable the conversion for hydroxyectoine production. We further investigated the effects of promoter, co-substrate ɑ-ketoglutarate, Fe²⁺ concentration, and dissolved oxygen on hydroxyectoine synthesis. Through fed-batch fermentation in a 7-L bioreactor, we significantly enhanced the hydroxyectoine production efficiency, attaining a final titer of 8.58 g/L and a productivity of 0.24 g/(L·h). This work successfully achieved the de novo synthesis of hydroxyectoine in E. coli, laying a foundation for the efficient bioproduction of this compound.
Escherichia coli/genetics* ; Fermentation ; Amino Acids, Diamino/biosynthesis* ; Bioreactors/microbiology* ; Metabolic Engineering/methods* ; Chromohalobacter/genetics* ; Plasmids/genetics*

WRKYs is a unique family of transcription factors (TFs) in plants, and belongs to the typical multifunctional regulator. It is involved in the regulation of multiple signaling pathways. This type of transcription factor is characterized to contain about 60 highly conservative amino acids as the WRKY domain, and usually also has the Cys2His2 or Cys2His-Cys zinc finger structure. WRKYs can directly bind to the W-box sequence ((T)(T) TGAC (C/T)) in the promoter region of the downstream target gene, and activate or inhibit the transcription of the target genes by interacting with the target protein. They may up-regulate the expression of stress-related genes through integrating signal pathways mediated by abscisic acid (ABA) and reactive oxygen species (ROS), thus playing a vital role in regulating plant response to abiotic stresses. This review summarizes the advances in research on the structure and classification, regulatory approach of WRKYs, and the molecular mechanisms of WRKYs involved in response to drought and salt stresses, and prospects future research directions, with the aim to provide a theoretical support for the genetic improvement of crop in response to abiotic stresses.
Transcription Factors/genetics* ; Abscisic Acid ; Amino Acids ; Droughts ; Stress, Physiological/genetics*

Objective: To investigate the relationship between amino acid variations of respiratory syncytial virus (RSV) nonstructural protein (NS) 1 and the clinical characteristics. Method: A retrospective case review was conducted. From December 2018 to January 2020, a total of 81 cases of hospitalized children who were tested only positive for RSV by RT-PCR or PCR at the Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University were included in the study. The NS1 genes of RSV subtype A and subtype B were amplified by PCR and sequenced. The amino acid sequences were analyzed. The Chi-square test and Mann-Whitney rank sum test were used to compare the clinical characteristics and type Ⅰ interferon levels of children with or without NS1 variation in the variation and non-variation groups. Results: Among 81 cases, there were 58 males and 23 females. There were 11 cases in the variation group, the age of onset was 2.0 (1.0, 11.0) months, included 4 cases of subtype A (variant sites were: 2 cases for Lys33Gln, one case for Gly2Asp, Pro67Ser, Leu137Phe, respectively) and 7 cases of subtype B (variant sites were: two cases for Val121Ile, one case for Tyr30Cys, Val65Met, Asn85Ser, Ser118Asn, Asp124Asn, respectively). These variant sites all appeared at a very low frequency 0.08 (0.04, 0.29) % in the NCBI PROTEIN database. There were 70 cases in non-variation group, the onset age was 3.5 (1.0, 7.0) months. The proportion of dyspnea in the variation group was higher than that in the non-variation group (10/11 vs. 47% (33/70), χ²=7.31, P<0.01). Conclusions: There are some variant sites in nonstructural protein NS1 of RSV. Children may be prone to have dyspnea with NS1 variations.
Child ; Male ; Female ; Humans ; Infant ; Respiratory Syncytial Virus Infections ; Amino Acids ; Retrospective Studies ; Respiratory Syncytial Virus, Human/genetics* ; Polymerase Chain Reaction

Tanshinones are one of the main effective components of Salvia miltiorrhiza, which play important roles in the treatment of cardiovascular diseases. Microbial heterogony production of tanshinones can provide a large number of raw materials for the production of traditional Chinese medicine(TCM) preparations containing S. miltiorrhiza, reduce the extraction cost, and relieve the pressure of clinical medication. The biosynthetic pathway of tanshinones contains multiple P450 enzymes, and the catalytic element with high efficiency is the basis of microbial production of tanshinones. In this study, the protein modification of CYP76AK1, a key P450-C20 hydroxylase in tanshinone pathway, was researched. The protein modeling methods SWISS-MODEL, Robetta, and AlphaFold2 were used, and the protein model was analyzed to obtain the reliable protein structure. The semi-rational design of mutant protein was carried out by molecular docking and homologous alignment. The key amino acid sites affecting the oxidation activity of CYP76AK1 were identified by molecular docking. The function of the obtained mutations was studied with yeast expression system, and the CYP76AK1 mutations with continuous oxidation function to 11-hydroxysugiol were obtained. Four key amino acid sites that affected the oxidation acti-vity were analyzed, and the reliability of three protein modeling methods was analyzed according to the mutation results. The effective protein modification sites of CYP76AK1 were reported for the first time in this study, which provides a catalytic element for different oxidation activities at C20 site for the study of the synthetic biology of tanshinones and lays a foundation for the analysis of the conti-nuous oxidation mechanism of P450-C20 modification.
Oxidoreductases ; Biosynthetic Pathways ; Molecular Docking Simulation ; Reproducibility of Results ; Salvia miltiorrhiza/chemistry* ; Amino Acids/metabolism* ; Plant Roots/genetics*

This study aimed to demonstrate the effect of Banxia Baizhu Tianma Decoction(BBTD) on realizing withdrawal of anti-epileptic drugs and explore the relationship between BBTD and the amino acid metabolism by transcriptomic analysis in the rat model of epilepsy induced by lithium chloride-pilocarpine. The rats with epilepsy were divided into a control group(Ctrl), an epilepsy group(Ep), a BBTD & antiepileptic drug integrative group(BADIG), and an antiepileptic drug withdrawal group(ADWG). The Ctrl and Ep were given ultrapure water by gavage for 12 weeks. The BADIG was given BBTD extract and carbamazepine solution by gavage for 12 weeks. The ADWG was given carbamazepine solution and BBTD extract by gavage for the former 6 weeks, and then only given BBTD extract for the latter 6 weeks. The therapeutic effect was evaluated by behavioral observation, electroencephalogram(EEG), and hippocampal neuronal morphological changes. High-throughput sequencing was used to obtain amino acid metabolism-related differen-tial genes in the hippocampus, and the mRNA expression in the hippocampus of each group was verified by real-time quantitative polymerase chain reaction(RT-qPCR). The hub genes were screened out through protein-protein interaction(PPI) network, and Gene Ontology(GO) functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis were performed. Two ceRNA networks, namely circRNA-miRNA-mRNA and lncRNA-miRNA-mRNA, were constructed for ADWG vs BADIG. The experimental results showed that compared with those in Ep, rats in ADWG were significantly improved in the behavioral observation, EEG, and hippocampal neuronal impairment. Thirty-four amino acid metabolism-related differential genes were obtained by transcriptomic analysis, and the sequencing results were confirmed by RT-qPCR. Eight hub genes were obtained through PPI network, involving several biological processes, molecular functions, and signal pathways related to amino acid metabolism. Finally, the circRNA-miRNA-mRNA ternary transcription network of 17 circRNA, 5 miRNA, and 2 mRNA, and a lncRNA-miRNA-mRNA ternary network of 10 lncRNA, 5 miRNA, and 2 mRNA were constructed in ADWG vs BADIG. In conclusion, BBTD can effectively achieve the withdrawal of antiepileptic drugs, which may be related to the transcriptomic regulation of amino acid metabolism.
Rats ; Animals ; RNA, Circular/genetics* ; Transcriptome ; RNA, Long Noncoding/genetics* ; Anticonvulsants ; MicroRNAs/genetics* ; RNA, Messenger ; Carbamazepine ; Amino Acids ; Gene Regulatory Networks

The gene GeDTC encoding the dicarboxylate-tricarboxylate carrier protein in Gastrodia elata was cloned by specific primers which were designed based on the transcriptome data of G. elata. Bioinformatics analysis on GeDTC gene was carried out by using ExPASY, ClustalW, MEGA, etc. Positive transgenic plants and potato minituber were obtained by virtue of the potato genetic transformation system. Agronomic characters, such as size, weight, organic acid content, and starch content, of potato minituber were tested and analyzed and GeDTC gene function was preliminarily investigated. The results showed that the open reading frame of GeDTC gene was 981 bp in length and 326 amino acid residues were encoded, with a relative molecular weight of 35.01 kDa. It was predicted that the theoretical isoelectric point of GeDTC protein was 9.83, the instability coefficient was 27.88, and the average index of hydrophilicity was 0.104, which was indicative of a stable hydrophilic protein. GeDTC protein had a transmembrane structure and no signal peptide and was located in the inner membrane of mitochondria. The phylogenetic tree showed that GeDTC was highly homologous with DTC proteins of other plant species, among which GeDTC had the highest homology with DcDTC(XP＿020675804.1) in Dendrobium candidum, reaching 85.89%. GeDTC overexpression vector pCambia1300-35Spro-GeDTC was constructed by double digests, and transgenic potato plants were obtained by Agrobacterium-mediated gene transformation. Compared with the wild-type plants, transgenic potato minituber harvested by transplanting had smaller size, lighter weight, lower organic acid content, and no significant difference in starch content. It is preliminarily induced that GeDTC is the efflux channel of tricarboxylate and related to the tuber development, which lays a foundation for further elucidating the molecular mechanism of G. elata tuber development.
Gastrodia/genetics* ; Phylogeny ; Amino Acids ; Cloning, Molecular

OBJECTIVES: Multiple myeloma (MM) is a plasma cell malignancy occurring in middle and old age. MM is still an incurable disease due to its frequent recurrence and drug resistance. However, its pathogenesis is still unclear. Abnormal amino acid metabolism is one of the important characteristics of MM, and the important metabolic pathway of amino acids participates in protein synthesis as basic raw materials. Aminoacyl transfer ribonucleic acid synthetase (ARS) gene is a key regulatory gene in protein synthesis. This study aims to explore the molecular mechanism for ARS, a key factor of amino acid metabolism, in regulating amino acid metabolism in MM and affecting MM growth. METHODS: The corresponding gene number was combined with the gene expression profile GSE5900 dataset and GSE2658 dataset in Gene Expression Omnibus (GEO) database to standardize the gene expression data of ARS. GSEA_4.2.0 software was used to analyze the difference of gene enrichment between healthy donors (HD) and MM patients in GEO database. GraphPad Prism 7 was used to draw heat maps and perform data analysis. Kaplan-Meier and Cox regression model were used to analyze the expression of ARS gene and the prognosis of MM patients, respectively. Bone marrow samples from 7 newly diagnosed MM patients were collected, CD138⁺ and CD138^- cells were obtained by using CD138 antibody magnetic beads, and the expression of ARS in MM clinical samples was analyzed by real-time RT-PCR. Human B lymphocyte GM12878 cells and human MM cell lines ARP1, NCI-H929, OCI-MY5, U266, RPMI 8266, OPM-2, JJN-3, KMS11, MM1.s cells were selected as the study objects. The expression of ARS in MM cell lines was analyzed by real-time RT-PCR and Western blotting. Short hairpin RNA (shRNA) lentiviruses were used to construct gene knock-out plasmids (VARS-sh group). No-load plasmids (scramble group) and gene knock-out plasmids (VARS-sh group) were transfected into HEK 293T cells with for virus packaging, respectively. Stable expression cell lines were established by infecting ARP1 and OCI-MY5 cells, and the effects of knockout valyl-tRNA synthetase (VARS) gene on proliferation and apoptosis of MM cells were detected by cell counting and flow cytometry, respectively. GEO data were divided into a high expression group and a low expression group according to the expression of VARS. Bioinformatics analysis was performed to explore the downstream pathways affected by VARS. Gas chromatography time-of-flight mass spectrometry (GC-TOF/MS) and high performance liquid chromatography (HPLC) were used to detect the valine content in CD138⁺ cells and ARP1, OCI-MY5 cells and supernatant of knockdown VARS gene in bone marrow samples from patients, respectively. RESULTS: Gene enrichment analysis showed that tRNA processing related genes were significantly enriched in MM compared with HD (P<0.0001). Further screening of tRNA processing-pathway related subsets revealed that cytoplasmic aminoacyl tRNA synthetase family genes were significantly enriched in MM (P<0.0001). The results of gene expression heat map showed that the ARS family genes except alanyl-tRNA synthetase (AARS), arginyl-tRNA synthetase (RARS), seryl-tRNA synthetase (SARS) in GEO data were highly expressed in MM (all P<0.01). With the development of monoclonal gammopathy of undetermined significance (MGUS) to MM, the gene expression level was increased gradually. Kaplan-Meier univariate analysis of survival results showed that there were significant differences in the prognosis of MM patients in methionyl-tRNA synthetase (MARS), asparaginyl-tRNA synthetase (NARS) and VARS between the high expression group and the low expression group (all P<0.05). Cox regression model multivariate analysis showed that the high expression of VARS was associated with abnormal overall survival time of MM (HR=1.83, 95% CI 1.10 to 3.06, P=0.021). The high expression of NARS (HR=0.90, 95% CI 0.34 to 2.38) and MARS (HR=1.59, 95% CI 0.73 to 3.50) had no effect on the overall survival time of MM patients (both P>0.05). Real-time RT-PCR and Western blotting showed that VARS, MARS and NARS were highly expressed in CD138⁺ MM cells and MM cell lines of clinical patients (all P<0.05). Cell counting and flow cytometry results showed that the proliferation of MM cells by knockout VARS was significantly inhibited (P<0.01), the proportion of apoptosis was significantly increased (P<0.05). Bioinformatics analysis showed that in addition to several pathways including the cell cycle regulated by VARS, the valine, leucine and isoleucine catabolic pathways were upregulated. Non-targeted metabolomics data showed reduced valine content in CD138⁺ tumor cells in MM patients compared to HD (P<0.05). HPLC results showed that compared with the scramble group, the intracellular and medium supernatant content of ARP1 cells and the medium supernatant of OCI-MY5 in the VARS-shRNA group was increased (all P<0.05). CONCLUSIONS MM patients with abnormal high expression of VARS have a poor prognosis. VARS promotes the malignant growth of MM cells by affecting the regulation of valine metabolism.
Humans ; Valine-tRNA Ligase ; Multiple Myeloma/genetics* ; Metabolomics ; Amino Acids ; RNA, Transfer

ω-transaminases are able to catalyze the reversible transfer of amino groups between diverse amino compounds (such as amino acids, alkyl amines, aromatic amines) and carbonyl compounds (such as aldehydes, ketones, ketoacids). ω-transaminases exhibit great application prospects in the field of chiral amine biosynthesis because of their desirable properties, such as wide range of substrates, high stereoselectivity, and mild catalytic conditions. It is therefore important for China to develop efficient, specific, and environment-friendly chiral amine production technologies with independent intellectual property rights, which is of great significance for the development of pharmaceutical, pesticide, and material industries. This review systematically summarizes the Chinese patents regarding ω-transaminase filed by Chinese institutions in the recent decade. The development of ω-transaminase resource, enzymatic property improvement by protein engineering, application in chiral amine synthesis, and development of production technologies are elaborated. This review will shed light on further basic and application studies of ω-transaminase.
Transaminases/genetics* ; Amino Acids ; China ; Aldehydes ; Amines

As a branched chain amino acid, L-valine is widely used in the medicine and feed sectors. In this study, a microbial cell factory for efficient production of L-valine was constructed by combining various metabolic engineering strategies. First, precursor supply for L-valine biosynthesis was enhanced by strengthening the glycolysis pathway and weakening the metabolic pathway of by-products. Subsequently, the key enzyme in the L-valine synthesis pathway, acetylhydroxylate synthase, was engineered by site-directed mutation to relieve the feedback inhibition of the engineered strain. Moreover, promoter engineering was used to optimize the gene expression level of key enzymes in L-valine biosynthetic pathway. Furthermore, cofactor engineering was adopted to change the cofactor preference of acetohydroxyacid isomeroreductase and branched-chain amino acid aminotransferase from NADPH to NADH. The engineered strain C. glutamicum K020 showed a significant increase in L-valine titer, yield and productivity in 5 L fed-batch bioreactor, up to 110 g/L, 0.51 g/g and 2.29 g/(L‧h), respectively.
Valine ; Corynebacterium glutamicum/genetics* ; Metabolic Engineering ; Amino Acids, Branched-Chain ; Bioreactors