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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay laboratory State Key laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences research Unit of Chemical Biology of Natural Anti-virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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A serologic investigation of epizootic hemorrhagic disease virus in China between 2014 and 2019

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Virologica Sinica 2022年第4期37卷 513-520页

作者： Yingliang Duan Zhenxing Yang Pei Zhu Lei Xiao Zhanhong Li Zhuoran Li Le Li Jianbo Zhu Yunnan Tropical and Subtropical Animal virus Diseases laboratory Yunnan Animal Science and Veterinary InstituteKunming650000China

Epizootic hemorrhagic disease virus(EHDV)is a member of the genus Orbivirus,family *** was firstly recognized in 1955 to cause a highly fatal disease of wild white-tailed deer in *** far,EHDV was detected and isolated in many wild or domestic ruminants,and widely distributed all over the *** the domestic cattle and sheep infected by EHDV were usually asymptomatic or subclinical,several outbreaks of epizootic hemorrhagic disease(EHD)in deer and cattle had been *** EHDV strains were isolated and sequenced in last two decades in China,which promoted a general serologic investigation of EHDV in *** this study,18,122 sera were collected from asymptomatic or subclinical domestic ruminants(cattle,cow,yaks,sheep,goats,and deer)in 116 regions belonging to 15 provinces in *** the sera were tested by EHDV CELISA,and the results were obtained by big data *** infections were detected in the 14 of 15provinces,and only Tibet(average altitude≥4000 m)which was the highest province in China was free of *** numbers of seropositive collections in both bovine and goat/sheep were in an inverse proportion to the ***,the seropositive rates in bovine were ranged from 0%to 100%,while the seropositive rates in goat/sheep were no more than 50%.The results suggested that bovine was obviously more susceptive for EHDV infection than goat and sheep,therefore might be a major reservoir of EHDV in *** prevalence of EHDV was consistent with the distribution of Culicoides which were known as the sole insect vectors of *** particular,the seropositive rates of EHDV were very high in the southern provinces,which required the enhanced surveillance in the future.

关键词： Epizootic hemorrhagic disease virus(EHDV) Prevalence Ruminant China

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CLINICAL OBSERVATION ON VERTICAL TRANSMISSION OF HUMAN PAPILLOMA virus

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Chinese Medical Sciences Journal 1998年第1期13卷 29-31页

作者：徐倏燊刘兰青吕绳敏任舒月 virus laboratory Second Hospital of China Medical University Shenyang 110003

Objective. To observe the possibility of maternal-fetal vertical transmission of human papillomavirus (HPV)via amniotic fluid. Subjects and methods. Specimens of cervical secretions from 30 pregnant women were obtained during the third trimester before rupture of membrane, and specimens of pharyngeal secretions of their neonates were obtained 12-48 h after birth. Amniotic fluids were collected in 13 pregnant women during cesarean section. The presence of HPV types 6, 11, 16, 18, 31, 33, 35, 38 deoxyribonucleic acid were detected by consensus polymerase chain reaction. Results. HPV deoxyribonucleic acid was found in 16 cervical secretions, 14 pharyngeal secretions and in 3 amniotic fluids, the positive rate was 53. 3%, 46. 7%, 23. 1 % respectively. The pharyngeal secretion was also HPV positive in one of the three neonates from the amniotic fluid positive mothers. Conclusion. The results indicate that HPV can be transmitted in utero through amniotic fluid and cesarean section can not protect the neonates against vertical transmission completely.

关键词： papillomavirus polymerase chain reaction pregnancy

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Quantitative analysis of the interaction of heterologous viruses with Plum pox virus in C5 HoneySweet transgenic plums

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Journal of Integrative Agriculture 2019年第10期18卷 2302-2310页

作者： Khushwant Singh Tereza Neubauerová Jiban Kumar Kundu Plant virus and Vector Interactions Group Division of Crop Protection and Plant Health Crop Research Institute

Stone fruits are an important crop in most parts of the world and are heavily challenged by several viruses including Plum pox virus (PPV), Prune dwarf virus (PDV), Prunus necrotic ringspot virus (PNRSV), and Apple chlorotic leaf spot virus (ACLSV). We validated the PPV resistance in C5 plum plants (commercially known as HoneySweet) grown in the Czech Republic for more than 16 years in a field trial experiment under natural environmental conditions. We quantified single (PPV-Rec) and mixed viruses (PPV-Rec+ACLSV, PPV-Rec+PDV and PPV-Rec+ACLSV+PDV) in C5 transgenic plums inoculated for the period 2016 to 2018. The accumulation of PPV-Rec was high (~5.43E+05 copies) compared with that of ACLSV (~8.70E+04 copies) in the inoculated graft of C5 transgenic plants. Leaves close to the inoculum sources showed a differential level of virus titre in single and mixed infections (~10 to ~5×10^2 copies). C5 plants with permanent virus pressure showed 103- to 105-fold fewer copies of viruses than those of the inoculated graft. We observed high accumulation of conserved miRNAs such as miR167, miR69 and miR396 in C5 plants co-infected with PPV, ACLSV and PDV that are associated with its resistance against viruses. Overall, i) C5 transgenic plums showed high resistance to PPV infection, and a low level (~32 copies) of PPV only accumulated in some grafted plants, ii) high accumulation of PPV was found in inoculated grafts in single PPV infection and mixed infections, iii) heterologous virus infection sustained by ACLSV or PDV did not suppress PPV resistance, and iv) high and low conserved microRNAs accumulated in C5 plants.

关键词： PPV PDV ACLSV C5 HoneySweet resistance

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Effect of amino acid mutation at position 127 in 3A of a rabbitattenuated foot-and-mouth disease virus serotype Asia1 on viral replication and infection

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Virologica Sinica 2014年第5期29卷 291-298页

作者： Aiguo Xin Mingwang Zhu Qi Hu Haisheng Miao Zhenqi Peng Yuwen He Lin Gao Huachun Li Yunnan Tropical and Subtropical Animal virus Disease laboratory Yunnan Animal Science and Veterinary Institute Yunnan Provincial research Center for Veterinary Biological Products

An amino acid mutation(R127→I) in the 3A non-structural protein of an FMDV serotype Asia1 rabbit-attenuated ZB strain was previously found after attenuation of the virus. To explore the effects of this mutation on viral replication and infection, the amino acid residue isoleucine(I) was changed to arginine(R) in the infectious cDNA clone of the rabbit-attenuated ZB strain by sitedirected mutagenesis, and the R127-mutated virus was rescued. BHK monolayer cells and suckling mice were inoculated with the R127-mutated virus to test its growth property and pathogenicity, respectively. The effects of the R127 mutation on viral replication and virulence were analyzed. The data showed that there was a slight difference in plaque morphology between the R127-mutated and wild-type viruses. The growth rate of the mutated virus was lower in BHK-21 cells and its virulence in suckling mice was also attenuated. This study indicates that the R127 mutation in 3A may play an important role in FMDV replication in vitro and in pathogenicity in suckling mice.

关键词： foot-and-mouth disease virus(FMDV) 3A protein mutation replication ability virulence

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Micro-droplet Digital Polymerase Chain Reaction and Real-Time Quantitative Polymerase Chain Reaction Technologies Provide Highly Sensitive and Accurate Detection of Zika virus

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Virologica Sinica 2018年第3期33卷 270-277页

作者： Yuan Hui Zhiming Wu Zhiran Qin Li Zhu Junhe Liang Xujuan Li Hanmin Fu Shiyu Feng Jianhai Yu Xiaoen He Weizhi Lu Weiwei Xiao Qinghua Wu Bao Zhang Wei Zhao Guangdong Provincial Key laboratory of Tropical Disease research School of Public Health Southern Medical University Guangzhou 510515 China Jiangmen Center for Disease Control and Prevention Jiangmen 529085 China Guangzhou Key laboratory of Drug research for Emerging virus Prevention and Treatment School of PharmacySouthern Medical University Guangzhou 510515 China

The establishment of highly sensitive diagnostic methods is critical in the early diagnosis and control of Zika virus(ZIKV)and in preventing serious neurological complications of ZIKV infection. In this study, we established micro-droplet digital polymerase chain reaction(ddPCR) and real-time quantitative PCR(RT-qPCR) protocols for the detection of ZIKV based on the amplification of the NS5 gene. For the ZIKV standard plasmid, the RT-qPCR results showed that the cycle threshold(Ct) value was linear from 10~1 to 10~8 copy/l L, with a standard curve R^2 of 0.999 and amplification efficiency of 92.203%;however, a concentration as low as 1 copy/l L could not be detected. In comparison with RT-qPCR, the dd PCR method resulted in a linear range of 10~1–10~4 copy/l L and was able to detect concentrations as low as 1 copy/l L. Thus, for detecting ZIKV from clinical samples, RT-qPCR is a better choice for high-concentration samples(above 10~1 copy/l L),while ddPCR has excellent accuracy and sensitivity for low-concentration samples. These results indicate that the ddPCR method should be of considerable use in the early diagnosis, laboratory study, and monitoring of ZIKV.

关键词： Zika virus Nucleic acid detection - Micro-droplet digital polymerase chain reaction (ddPCR)Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR)

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Role of RNA secondary structure in emergence of compartment specific hepatitis B virus immune escape variants

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World Journal of Virology 2016年第4期5卷 161-169页

作者： Sibnarayan Datta Runu Chakravarty Molecular Virology laboratory Defence Research Laboratory (DRDO) Hepatitis research laboratory ICMR Virus Unit (ICMR)

AIM To investigate the role of subgenotype specific RNA secondary structure in the compartment specific selection of hepatitis B virus(HBV)immune escape *** This study was based on the analysis of the specific observation of HBV subgenotype A1 in the serum/plasma,while subgenotype A2 with G145R mutation in the peripheral blood leukocytes(PBLs).Genetic variability found among the two subgenotypes was used for prediction and comparison of the full length pregenomic RNA(pgRNA)secondary structure and base *** secondary structures were predicted for 37℃using the Vienna RNA fold server,using default *** and detailed analysis was done using RNA shapes *** In this analysis,using similar algorithm and conditions,entirely different pgRNA secondary structures for subgenotype A1 and subgenotype A2 were predicted,suggesting different base pairing patterns within the two subgenotypes of genotype A,specifically,in the HBV genetic region encoding the major hydrophilic *** observed that for subgenotype A1 specific pgRNA,nucleotide 358U base paired with 1738A and nucleotide 587G base paired with *** in sharp contrast,in subgenotype A2 specific pgRNA,nucleotide 358U was opposite to nucleotide 588G,while 587G was opposite to 359U,hence precluding correct base pairing and thereby lesser stability of the stem *** the nucleotides at 358U and 587G were replaced with 358C and 587A respectively(as observed specifically in the PBL associated A2 sequences),these nucleotides base paired correctly with 588G and 359U,*** The results of this study show that compartment specific mutations are associated with HBV subgenotype specific alterations in base pairing of the pgRNA,leading to compartment specific selection and preponderance of specific HBV subgenotype with unique mutational pattern.

关键词： Hepatitis B Compartmentalization Peripheral blood leukocytes pgRNA RNA secondary structure G145R

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Malicious Document Detection Based on GGE Visualization

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Computers, Materials & Continua 2025年第1期82卷 1233-1254页

作者： Youhe Wang Yi Sun Yujie Li Chuanqi Zhou Henan Province Key laboratory of Information Security Information Engineering UniversityZhengzhou450000China

With the development of anti-virus technology,malicious documents have gradually become the main pathway of Advanced Persistent Threat(APT)attacks,therefore,the development of effective malicious document classifiers has become particularly ***,detection methods based on document structure and behavioral features encounter challenges in feature engineering,these methods not only have limited accuracy,but also consume large resources,and usually can only detect documents in specific formats,which lacks versatility and *** address such problems,this paper proposes a novel malicious document detection method-visualizing documents as GGE images(Grayscale,Grayscale matrix,Entropy).The GGE method visualizes the original byte sequence of the malicious document as a grayscale image,the information entropy sequence of the document as an entropy image,and at the same time,the grayscale level co-occurrence matrix and the texture and spatial information stored in it are converted into grayscale matrix image,and fuses the three types of images to get the GGE color *** Convolutional Block Attention Module-EfficientNet-B0(CBAM-EfficientNet-B0)model is then used for classification,combining transfer learning and applying the pre-trained model on the ImageNet dataset to the feature extraction process of GGE *** shown in the experimental results,the GGE method has superior performance compared with other methods,which is suitable for detecting malicious documents in different formats,and achieves an accuracy of 99.44%and 97.39%on Portable Document Format(PDF)and office datasets,respectively,and consumes less time during the detection process,which can be effectively applied to the task of detecting malicious documents in real-time.

关键词： Malicious document visualization EfficientNet-B0 convolutional block attention module GGE image

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AGO2a but not AGO2b mediates antiviral defense against infection of wild-type cucumber mosaic virus in tomato

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Horticulture research 2023年第5期10卷 38-48页

作者： Liling Zhao Yingfang Chen Xingming Xiao Haiying Gao Jiamin Cao Zhongkai Zhang Zhongxin Guo Vector-borne virus research Center State Key Laboratory for Ecological Pest Control of Fujian and Taiwan CropsCollege of Plant ProtectionFujian Agriculture and Forestry UniversityFuzhou 350002 China 2Key laboratory of Agricultural Biotechnology of Yunnan Province Biotechnology and Germplasm Resources Research InstituteYunnan Academy of Agricultural SciencesKunming650221 China

Evolutionarily conserved antiviral RNA interference(RNAi)mediates a primary antiviral innate immunity preventing infection of broad-spectrum viruses in ***,the detailed mechanism in plants is still largely unknown,especially in important agricultural crops,including *** of pathogenic viruses evolve to possess viral suppressors of RNA silencing(VSRs)to suppress antiviral RNAi in the *** to the prevalence of VSRs,it is still unknown whether antiviral RNAi truly functions to prevent invasion by natural wild-type viruses in plants and *** this research,for the first time we applied CRISPR-Cas9 to generate ago2a,ago2b,or ago2ab mutants for two differentiated Solanum lycopersicum AGO2s,key effectors in antiviral *** found that AGO2a but not AGO2b was significantly induced to inhibit the propagation of not only VSR-deficient Cucumber mosaic virus(CMV)but also wild-type CMV-Fny in tomato;however,neither AGO2a nor AGO2b regulated disease induction after infection with either *** findings firstly reveal a prominent role of AGO2a in antiviral RNAi innate immunity in tomato and demonstrate that antiviral RNAi evolves to defend against infection of natural wild-type CMV-Fny in ***,AGO2a-mediated antiviral RNAi does not play major roles in promoting tolerance of tomato plants to CMV infection for maintaining health.

关键词： immunity invasion media

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Multiple Roles of HIV-1 Capsid during the virus Replication Cycle

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Virologica Sinica 2019年第2期34卷 119-134页

作者： Mariia Novikova Yulan Zhang Eric O. Freed Ke Peng virus-Cell Interaction Section HIV Dynamics and Replication Program Center for Cancer Research National Cancer Institute Frederick MD 21702 USA State Key laboratory of Virology Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China

Human immunodeficiency virus-1 capsid(HIV-1 CA) is involved in different stages of the viral replication cycle. During virion assembly, CA drives the formation of the hexameric lattice in immature viral particles, while in mature virions CA monomers assemble in cone-shaped cores surrounding the viral RNA genome and associated proteins. In addition to its functions in late stages of the viral replication cycle, CA plays key roles in a number of processes during early phases of HIV-1 infection including trafficking, uncoating, recognition by host cellular proteins and nuclear import of the viral preintegration complex. As a result of efficient cooperation of CA with other viral and cellular proteins, integration of the viral genetic material into the host genome, which is an essential step for productive viral infection, successfully occurs. In this review, we will summarize available data on CA functions in HIV-1 replication, describing in detail its roles in late and early phases of the viral replication cycle.

关键词： Human immunodeficiency virus-1 (HIV-1) Capsid (CA) Assembly Post entry Uncoating and nuclear import Inhibitor

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