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Phylogenetic Relationships of 11 Bumblebee Species (Hymenoptera:Apidae) Based on Mitochondrial Cytochrome b Gene Sequences 被引量:7
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作者 邵志勇 茅红新 +1 位作者 符文俊 张亚平 《Zoological Research》 CAS CSCD 北大核心 2002年第5期361-366,共6页
Phylogenetic relationships of 11 bumblebee species,including 5 subgenera:Bombus (5 species),Thoracobombus (3 species),Mendacibombus (1 species),Fervidobombus (1 species) and Pyrobombus (1 species),were analyzed based ... Phylogenetic relationships of 11 bumblebee species,including 5 subgenera:Bombus (5 species),Thoracobombus (3 species),Mendacibombus (1 species),Fervidobombus (1 species) and Pyrobombus (1 species),were analyzed based on the 357?bp mitochondrial cytochrome b gene sequences.There are 65 singleton polymorphic sites and 71 parsimony informative polymorphic sites in this DNA segment,and 45 polymorphic sites within the total 119 translated amino acids segment.Both NJ tree and MP tree show that Mendacibombus (B.avinovielllus) is basal to others,followed by Fervidobombus (B.pensylvanicus);Pyrobombus (B.impatiens) and Bombus are sister subgenera;the subgenus of Bombus is monophyletic,in which B.ignitus diverged first. 展开更多
关键词 BOMBUS Cytochrome b gene DNA sequence Amino acid sequence Molecular phylogeny
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Rice bicoid-related cDNA sequence and its expression during early embryogenesis 被引量:3
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作者 YangZX AnGY 《Cell Research》 SCIE CAS CSCD 2001年第1期74-80,共7页
Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accessio... Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accession number: AJ2771380), was isolated by screening of rice unmature seed cDNA library. Sequence analysis indicates that Rb24 contains a putative amino acid sequence, which is homologous to unique 8 amino acids sequence within Drosophila bicoid homeodomain (50% identity, 75% similarity) and involves a lys-9 in putative helix 3. Northern blot analysis of rice RNA has shown that this sequence is expressed in a tissue-specific manner. The transcript was detected strongly in young panicles, but less in young leaves and roots. This results are further confirmed with paraffin section in situ hybridization. The signal is intensive in rice globular embryo and located at the apical tip of the embryo, then, along with the development of embryo, the signal is getting reduced and transfers into both sides of embryo. The existence of bicoid-related sequence in rice embryo and the similarity of polar distribution of bicoid and Rb24 mRNA in early embryo development may implicates a conserved maternal regulation mechanism of body axis presents in Drosophila and in rice. 展开更多
关键词 Base sequence Body Patterning Cloning Molecular DNA Complementary Gene Expression Regulation Plant Genes Plant Homeodomain Proteins Molecular sequence Data Oryza sativa Protein Structure Tertiary Research Support Non-U.S. Gov't Seeds sequence Homology Nucleic Acid TRANS-ACTIVATORS
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Analysis of the N Protein Sequence Variability in 13 Isolated PRRSV Strains from China
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作者 Yang Xia Baodan Huang +4 位作者 Bin Wu Yi Zhang Maole Yan Yan Li Jida Li 《Journal of Biosciences and Medicines》 2021年第2期63-75,共13页
<strong>Object</strong>: To analyze porcine reproductive and respiratory syndrome virus (PRRSV) strains from 13 infection cases via the N protein gene and its encoded amino acid sequence and to provide a t... <strong>Object</strong>: To analyze porcine reproductive and respiratory syndrome virus (PRRSV) strains from 13 infection cases via the N protein gene and its encoded amino acid sequence and to provide a theoretical basis for the epidemiological study, prevention and control of porcine reproductive and respiratory syndrome (PRRS). <strong>Methods</strong>: In clinically suspected PRRSV infections, viruses were isolated by extracting viral nucleic acid and amplifying the N protein gene by RT-PCR. Then, the product was purified and sequenced to acquire the whole gene sequence of the N protein and its encoded amino acid sequence. DNASTAR software was used to analyze the homology, the genetic evolution and the derivation of the variability of amino acids of the N protein gene from 13 PRRSV strains and classical domestic and foreign strains. <strong>Results</strong>: Among the thirteen strains of PRRSV isolated from this study, ten strains had the greatest homology with the JXA1 strain (98.9% - 100%), and they belonged to the sublineage 8.7. The remaining three strains had the greatest homology with the NADC30 strain (95.4% - 97.1%), and they belonged to lineage one. The analysis of the variability of N protein amino acids showed that there were high frequency mutations in the five loci of 13 isolated strains of PRRSV as follows: 15th amino acid (10/13), 46<sup>th</sup> amino acid (11/13), 91st amino acid (10/13), 109th amino acid (10/13), and 117th amino acid (10/13). <strong>Conclusion</strong>: In recent years, sublineage 8.7 was the dominant pedigree in field PRRSV epidemic strains in China with lineage one occupying a certain proportion of the field. Four high frequency mutations existed in N protein antigen epitopes of isolated strains from the region. The nuclear localization signal (NLS) structure, specifically the 46<sup>th</sup> amino acid residue of the N protein, was mutated and genetically stable. 展开更多
关键词 PRRSV Nucleocapsid Protein Nuclear Location Signal EPIDEMIOLOGICAL Amino Acid sequence
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Comprehensive molecular analysis to predict the efficacy ofchemotherapy containing bevacizumab in patients with metastaticcolorectal cancer 被引量:1
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作者 SUNG HEE LIM HEE JIN CHO +6 位作者 KYOUNG-MEE KIM HO YEONG LIM WON KI KANG JEEYUN LEE YOUNG SUK PARK HEE CHEOL KIM SEUNG TAE KIM 《Oncology Research》 SCIE 2023年第6期855-866,共12页
Background:Although bevacizumab is an important treatment for metastatic colorectal cancer(CRC),not allpatients with CRC benefit from it;in unselected patient populations,only modest survival benefits have been report... Background:Although bevacizumab is an important treatment for metastatic colorectal cancer(CRC),not allpatients with CRC benefit from it;in unselected patient populations,only modest survival benefits have been reported.Methods:We evaluated clinical outcomes in 110 patients using comprehensive molecular characterization to identifybiomarkers for a response to bevacizumab-containing treatment.The molecular analysis comprised whole-exomesequencing,ribonucleic acid sequencing,and a methylation array on patient tissues.Results:Genomic and molecularcharacterization was successfully conducted in 103 patients.Six of 103 CRC samples were hypermutated,and none ofthe non-hypermutant tumors were microsatellite unstable.Among those 103 patients,89 had adenocarcinoma(ADC),15 were diagnosed with mucinous ADC,and six had signet-ring cell carcinoma(SRCC).Consensus molecular subtype(CMS)2 was unique to ADC.Of the four SRCCs,two were CMS1,one was CMS4,and the other was CMS3.APCmutation status was a significantly enriched factor in responders to bevacizumab treatment.Fibroblast growth factorreceptor(FGFR)1/2 signaling was upregulated in non-responders,whereas cell cycle,transfer ribonucleic acidprocessing,nucleotide excision repair,and oxidative phosphorylation pathways were enriched in responders.Inaddition,IGF1 was differentially expressed in non-responders(log2 fold change=−1.43,p=4.11×10^(−5),falsediscovery rate=0.098),and FLT1 was highly methylated in non-responders(p=7.55×10^(−3)).When the molecularpathways were reanalyzed separately according to the backbone chemotherapy(FOLFOX vs.FOLFIRI),thesignificance of the molecular pathways varied according to the backbone chemotherapy.Conclusions:This studysought a subset of CRC patients with a distinct clinical response to chemotherapy containing bevacizumab.Ourresults need to be validated in a large group of homogenous patient cohort and examined according to the differentchemotherapy backbones to create personalized therapeutic opportunities in CRC. 展开更多
关键词 BEVACIZUMAB Whole-exome sequencing Ribonucleic acid sequencing Methylation array Colorectal cancer
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Micro-heterogeneity of Storage Glutelin in Rice Seed 被引量:4
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作者 曲乐庆 魏晓丽 +3 位作者 佐藤光 小川雅广 熊丸敏博 贾旭 《Acta Botanica Sinica》 CSCD 2001年第8期815-820,共6页
The storage glutelin in rice ( Oryza sativa L.) seeds could be separated at least into more than 13 acidic and 19 basic polypeptides by two dimensional electrophoresis. Rice glutelin might be mainly controlled by abou... The storage glutelin in rice ( Oryza sativa L.) seeds could be separated at least into more than 13 acidic and 19 basic polypeptides by two dimensional electrophoresis. Rice glutelin might be mainly controlled by about six major genes according to the expression of glutelin polypeptides. The acidic polypeptide of glutelin could be clearly separated into two groups by peptide mapping and N-terminal amino acid sequence analysis. These two groups were just in accord with the GluA and GluB subfamilies exactly. 展开更多
关键词 rice glutelin two-dimensional electrophoresis N-terminal amino acid sequence
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Detection of anti-preS1 antibodies for recovery of hepatitis B patients by immunoassay 被引量:15
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作者 Jun Wei Guang-Di Li Yuan Wang Zu-Chuan Zhang,Institute of Biochemsitry and Cell Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China Yu-Qin Wang Zhi-Meng Lu,Department of Clinical virology,Rui-Jin Hospital,Shanghai Second Medical University 200025,Shanghai,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期276-281,共6页
AIM: To establish a convenient immunoassay method based on recombinant antigen preS1(21-119aa) to detect anti-preS1 antibodies and evaluate the clinical significance of antibodies in hepatitis B. METHODS: The expressi... AIM: To establish a convenient immunoassay method based on recombinant antigen preS1(21-119aa) to detect anti-preS1 antibodies and evaluate the clinical significance of antibodies in hepatitis B. METHODS: The expression plasmid pET-28a-preS1 was constructed, and a large quantity of preS1(21-119aa) fragment of the large HBsAg protein was obtained. The preS1 fragment purified by Ni(2+)-IDA affinity chromatography was used as coated antigen to establish the indirect ELISA based on streptavidin-biotin system for detection of the anti-preS1 antibodies in sera from HBV-infected patients. For follow-up study, serial sera were collected during the clinical course of 21 HBV-infected patients and anti-preS1 antibodies, preS1 antigen, HBV-DNA and other serological HBV markers were analyzed. RESULTS: preS1(21-119aa) fragment was highly expressed from the plasmid pET-28a-preS1 in a soluble form in E.Coli (30mg.L(-1)), and easily purified to high purity over 90% by one step of Ni(2+)-IDA-sepharose 6B affinity chromatography. The purity and antigenicity of the purified preS1(21-119aa) protein was determined by 150g.L(-1) SDS-PAGE, Western blot and a direct ELISA. Recombinant preS1(21-119aa) protein was successfully applied in the immunoassay which could sensitively detect the anti-preS1 antibodies in serum specimens of acute or chronic hepatitis B patients. Results showed that more than half of 19 acute hepatitis B patients produced anti-preS1 antibodies during recovery of the disease, however, the response was only found in a few of chronic patients. In the clinical follow-up study of 11 patients with anti-preS1 positive serological profile, HBsAg and HBV-DNA clearance occurred in 6 of 10 acute hepatitis B patients in 5-6 months, and seroconversion of HBeAg and disappearance of HBV-DNA occurred in 1 chronic patients treated with lavumidine, a antiviral agent. CONCLUSION: The high-purity preS1(21-119aa) coated antigen was successfully prepared by gene expression and affinity chromatography. Using this antigen, a conveniently detective system of anti-preS1 antibodies in sera was established. Preliminarily clinical trial the occurrence of anti-preS1 antibodies in acute hepatitis B patients suggests the clearance of HBV from serum in a short-term time, and anti-preS1 positive in chronic patients means health improvement or recovery from the disease. 展开更多
关键词 Amino Acid sequence ANTIBODIES Base sequence Genetic Vectors Hepatitis B Hepatitis B Surface Antigens Humans IMMUNOASSAY Molecular sequence Data Peptide Fragments Protein Precursors Recombinant Fusion Proteins Research Support Non-U.S. Gov't Viral Envelope Proteins
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Expression of liver cancer associated gene HCCA3 被引量:9
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作者 Zheng-Xu Wang~1 Gui-Fang Hu~1 Hong-Yang Wang~2 Meng-Chao Wu~2 1 Department of General Surgery,Chinese PEA General Hospital of Lanzhou Military Command,Lanzhou 730050,Gansu Province,China2 Eastern Hepatobilliary Surgical Hospital,Second Military Medical University,Shanghai 200438,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期821-825,共5页
AIM: To study and clone a novel liver cancer related gene, and to explore the molecular basis of liver cancer genesis. METHODS: Using mRNA differential display polymerase chain reaction (DDPCR), we investigated the di... AIM: To study and clone a novel liver cancer related gene, and to explore the molecular basis of liver cancer genesis. METHODS: Using mRNA differential display polymerase chain reaction (DDPCR), we investigated the difference of mRNA in human hepatocellular carcinoma (HCC) and paired surrounding liver tissues, and got a gene probe. By screening a human placenta cDNA library and genomic homologous extend, we obtained a full-length cDNA named HCCA3. We analyzed the expression of this novel gene in 42 pairs of HCC and the surrounding liver tissues, and distribution in human normal tissues by means of Northern blot assay. RESULTS: A full-length cDNA of liver cancer associated gene HCCA3 has been submitted to the GeneBank nucleotide sequence databases (Accession No. AF276707). The positive expression rate of this gene was 78.6% (33/42) in HCC tissues, and the clinical pathological data showed that the HCCA3 was closely associated with the invasion of tumor capsule (P=0.023) and adjacant small metastasis satellite nodules lesions (P=0.041). The HCCA3 was widely distributed in the human normal tissues, which was intensively expressed in lungs, brain and colon tissues, while lowly expressed in the liver tissues. CONCLUSION: A novel full-length cDNA was cloned and differentiated, which was highly expressed in liver cancer tissues. The high expression was closely related to the tumor invasiveness and metastasis,that may be the late heredited change in HCC genesis. 展开更多
关键词 Gene Expression ADULT Aged Amino Acid sequence Base sequence FEMALE Humans Liver Neoplasms Male Middle Aged Molecular sequence Data PROTEINS Research Support Non-U.S. Gov't
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Identification of the epitopes on HCV core protein recognized by HLA-A2 restricted cytotoxic T lymphocytes 被引量:11
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作者 Hong-Chao Zhou De-Zhong Xu Xue-Ping Wang Jing-Xia Zhang Ying-Huang Yong-Ping Yan Yong Zhu Bo-Quan Jin Department of Epidemiology,the Fourth Military Medical University,Xi’an 710033,Shaanxi Province,ChinaDepartment of Immunology,the Fourth Military Medical University,Xi’an 710033,Shaanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第4期583-586,共4页
AIM: To identify hepatitis C virus(HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL). METHODS: Utilizing the method of computer prediction followed by a 4h(51)Cr release assay con... AIM: To identify hepatitis C virus(HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL). METHODS: Utilizing the method of computer prediction followed by a 4h(51)Cr release assay confirmation. RESULTS: The results showed that peripheral blood mononuclear cells (PBMC) obtained from two HLA-A2 positive donors who were infected with HCV could lyse autologous target cells labeled with peptide &quot;ALAHGVRAL (core 150-158)&quot;. The rates of specific lysis of the cells from the two donors were 37.5% and 15.8%, respectively. Blocking of the CTL response with anti-CD4 mAb caused no significant decrease of the specific lysis. But blocking of CTL response with anti-CD8 mAb could abolish the lysis. CONCLUSION: The peptide (core 150-158) is the candidate epitope recognized by HLAA2 restricted CTL. 展开更多
关键词 Amino Acid sequence Antibodies Viral B-LYMPHOCYTES Cell Line Epitope Mapping HLA-A2 Antigen HEPACIVIRUS Hepatitis C Humans Peptide Fragments Predictive Value of Tests Research Support Non-U.S. Gov't T-Lymphocytes Cytotoxic Viral Core Proteins
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Preparation of protein samples for gel electrophoresis by sequential extraction 被引量:15
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作者 钟伯雄 翁宏飚 《Journal of Zhejiang University Science》 CSCD 2002年第5期606-610,共5页
Since preparation and solubilization of protein samples are crucial factors in proteome research,the authors established a sequential extraction technique to prepare protein samples from the body wall of the 5th insta... Since preparation and solubilization of protein samples are crucial factors in proteome research,the authors established a sequential extraction technique to prepare protein samples from the body wall of the 5th instar larvae of silkworm.Bombyx mori.Two kinds of protein samples were obtained from the body wall using the method.Between the two types of samples only about 15% proteins were identical;the majority were different,indicating that more species of proteins could be obtained with the sequential extraction method;which will be useful for preparation of protein samples for proteome study. 展开更多
关键词 PROTEOME Sequential extraction 2D electrophoresis Protein spot match Amino acid sequence
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Identification and characterization of a novel isoform of hepatopoietin 被引量:8
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作者 Jun Lu Wei-Min Cai,Institute of Infectious Disease,First Affiliated Hospital,Medical SchooI,Zhejiang University,Hangzhou 310003 China Wang-Xiang Xu Yi-Qun Zhan Xiao-Lin Cui Fu-Chu He Xiao-Ming Yang,Institute of Radiation Medicine,Academy of Military Medical Sciences,Beijing 100850,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期353-356,共4页
AIM: To isolate a novel isoform of human HPO (HPO-205) from human fetal liver Marathon-ready cDNA and characterize its primary biological function. METHODS: 5'-RACE (rapid amplification of cDNA 5' ends) was us... AIM: To isolate a novel isoform of human HPO (HPO-205) from human fetal liver Marathon-ready cDNA and characterize its primary biological function. METHODS: 5'-RACE (rapid amplification of cDNA 5' ends) was used to isolate a novel isoform of hHPO in this paper. The constructed pcDNA(HPO-205), pcDNA(HPO) and pcDNA eukaryotic expression vectors were respectively transfected by lipofectamine method and the stimulation of DNA synthesis was observed by (3)H-TdR incorporation assay. Proteins extracted from different cells were analyzed by Western blot. RESULTS: A novel isoform of hHPO (HPO-205) encoding a 205 amino acid ORF corresponding to a translated production of 23 kDa was isolated and distinguished from the previous HPO that lacked the N-terminal 80 amino acids. The dose-dependent stimulation of DNA synthesis of HepG2 hepatoma cells by HPO-205 demonstrated its similar biological activity with HPO in vitro. The level of MAPK (Mitogen-activated protein kinase) phosphorylation by Western blot analysis revealed that HPO-205 might have the stronger activity of stimulating hepatic cell proliferation than that of HPO. CONCLUSION: A novel isoform of hHPO (HPO-205) was isolated from hepatic-derived cells. The comparison of HPO-205 and HPO will lead to a new insight into the structure and function of hHPO, and provide the new way of thinking to deeply elucidate the biological roles of HPO/ALR. 展开更多
关键词 Amino Acid sequence Cell Division Cell Fractionation Enzyme Activation Hepatocyte Growth Factor PURIFICATION Humans Liver Mitogen-Activated Protein Kinases Molecular sequence Data Open Reading Frames Protein Isoforms sequence Alignment Tumor Cells Cultured
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A Novel Polypeptide from Cervus elaphus Linnaeus 被引量:8
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作者 LiangWENG QiuLiZHOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第2期147-150,共4页
A novel polypeptide having stimulant effect on some cell proliferation was isolated from the velvet antler (Cervus elaphus Linnaeus). The velvet antler polypeptide consists of a single chain of 32 amino acid residues... A novel polypeptide having stimulant effect on some cell proliferation was isolated from the velvet antler (Cervus elaphus Linnaeus). The velvet antler polypeptide consists of a single chain of 32 amino acid residues. Amino acid sequence of the polypeptide was identified as: VLSAADKSNVKAAWGKVGGNAPAFGAEALLRM. 展开更多
关键词 Velvet antler PEPTIDE amino acid sequence.
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Recombinant scorpion insectotoxin AaIT kills specifically insect cells but not human cells 被引量:5
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作者 SHENG JIAN JI, FENG LIU, ER Qiu LI, Yu XIAN ZHUThe National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China 《Cell Research》 SCIE CAS CSCD 2002年第2期143-150,共8页
The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was ... The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was confirmed by N-terminal peptide sequencing. Two groups of bioassays, artificial diet incorporation assay and contact insecticidal effect assay, were carried out separately to verify the toxicity of this recombinant toxin. At the end of a 24 h experimental period, more than 60% of the testing diamondback moth (Plutella xylostella) larvae were killed in both groups with LC50 value of 18.4 microM and 0.70 microM respectively. Cytotoxicity assay using cultured Sf9 insect cells and MCF-7 human cells demonstrated that the toxin AaIT had specific toxicity against insect cells but not human cells. Only 0.13 microM recombinant toxin was needed to kill 50% of cultured insect cells while as much as 1.3 microM toxin had absolutely no effect on human cells. Insect cells produced obvious intrusions from their plasma membrane before broken up. We infer that toxin AaIT bind to a putative sodium channel in these insect cells and open the channel persistently, which would result in Na+ influx and finally cause destruction of insect cells. 展开更多
关键词 Amino Acid sequence Animals Base sequence Biological Assay Cell Line Cloning Molecular Dose-Response Relationship Drug Electrophoresis Polyacrylamide Gel Escherichia coli Humans Inhibitory Concentration 50 INSECTS Molecular sequence Data Peptides Protein Structure Tertiary Recombinant Proteins Research Support Non-U.S. Gov't Scorpion Venoms sequence Analysis Protein Sodium Time Factors Tumor Cells Cultured
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Family-level diversity of extracellular proteases of sedimentary bacteria from the South China Sea 被引量:3
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作者 Jinyu Yang Yangyang Feng +4 位作者 Xiulan Chen Binbin Xie Yuzhong Zhang Mei Shi Xiying Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第12期73-83,共11页
Protease-producing bacteria and their extracellular proteases are key players in degrading organic nitrogen to drive marine nitrogen cycling and yet knowledge on both of them is still very limited. This study screened... Protease-producing bacteria and their extracellular proteases are key players in degrading organic nitrogen to drive marine nitrogen cycling and yet knowledge on both of them is still very limited. This study screened protease-producing bacteria from the South China Sea sediments and analyzed the diversity of their extracellular proteases at the family level through N-terminal amino acid sequencing. Results of the 16 S rRNA gene sequence analysis showed that all screened protease-producing bacteria belonged to the class Gammaproteobacteria and most of them were affiliated with different genera within the orders Alteromonadales and Vibrionales. The Nterminal amino acid sequence analysis for fourteen extracellular proteases from fourteen screened bacterial strains revealed that all these proteases belonged to the M4 family of metalloproteases or the S8 family of serine proteases. This study presents new details on taxa of marine sedimentary protease-producing bacteria and types of their extracellular proteases, which will help to comprehensively understand the process and mechanism of the microbial enzymatic degradation of marine sedimentary organic nitrogen. 展开更多
关键词 protease-producing bacteria DIVERSITY extracellular proteases protease families N-terminal amino acid sequencing South China Sea
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Identification and Characterization of Peptide Mimics of Blood Group A Antigen 被引量:3
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作者 汤兆明 王琳 +4 位作者 胡丽华 李一荣 崔天盆 熊娟 窦丽芳 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第2期222-226,共5页
In order to investigate peptide mimics of carbohydrate blood group A antigen, a phage display 12-mer peptide library was screened with a monoclonal antibody against blood group A antigen, NaM87-1F6. The antibody-bindi... In order to investigate peptide mimics of carbohydrate blood group A antigen, a phage display 12-mer peptide library was screened with a monoclonal antibody against blood group A antigen, NaM87-1F6. The antibody-binding properties of the selected phage peptides were evaluated by phage ELISA and phage capture assay. The peptides were co-expressed as glutathione S-transferase (GST) fusion proteins. RBC agglutination inhibition assay was performed to assess the natural blood group A antigen-mimicking ability of the fusion proteins. The results showed that seven phage clones selected bound to NaM87-1F6 specifically, among which, 6 clones bore the same peptide sequence, EYWYCGMNRTGC and another harbored a different one QIWYERTLPFTF. The two peptides were successfully expressed at the N terminal of GST protein. Both of the fusion proteins inhibited the RBC agglutination mediated by anti-A serum in a concentration-dependent manner. These results suggested that the fusion proteins based on the selected peptides could mimic the blood group A antigen and might be used as anti-A antibody-adsorbing materials when immunoabsorption was applied in ABO incompatible transplantation. 展开更多
关键词 amino acid sequence blood group A antigen hemagglutination test molecular mimicry peptide library
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Relationship between genotype and phenotype of flagellin C in Salmonella 被引量:2
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作者 Wan-Sheng Ji~1 Jia-Lu Hu~1 Jun-Wen Qiu~1 Bo-Rong Pan~1 Dao-Rong Peng~2 Bing-Long Shi~1 Shao-Juan Zhou~1 Kai-Chun Wu~1 Dai-Ming Fan~1 1 Chinese PLA Institute of Digestive Diseases2 Department of Bacteriology,Xijing Hospital,Fourth Military Medical University,Xi’an 710032,Shaanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期864-867,共4页
AIM: To discover the relationship between the genotype and antigen serotype of flagellin C among Salmonella strains. METHODS: Fragment of Salmonella flagellin C in plasmid pLS408 was cloned, sequenced and compared wit... AIM: To discover the relationship between the genotype and antigen serotype of flagellin C among Salmonella strains. METHODS: Fragment of Salmonella flagellin C in plasmid pLS408 was cloned, sequenced and compared with the corresponding sequence in other strains. Salmonella strains including two typhi strains, one paratyphoid strain, one enteritidis and one typhimurium strain were isolated from outpatients. Genome DNA was purified respectively from these clinical isolates, then the corresponding flagellin C fragment was amplified by polymerase chain reaction,and the amplification products were analyzed by agarose gel electrophoresis. RESULTS: The cloned fragment includes 582 nucleotides encoding the variable region and partial conservative region of Salmonella flagellin C in plasmid pLS408. With comparison to the corresponding sequences reported previously, there is only a little difference from other strains with the same flagellar serotype in both nucleotide and amino acid level. Specific PCR products were amplified in Salmonella strains with flagellar serotype H-1-d including S. muenchen, typhi and typhimurium, but not in S. paratyphoid C or S. enteritidis strains. CONCLUSION: In this experiment, the specificity of nucleotide sequence could be found in flagellin C central variable regions as it exists in flagellar serotypes in Salmonella. It may be helpful to developing a rapid, sensitive, accurate and PCR-based method to detect Salmonella strains with serotype H-1-d. 展开更多
关键词 Amino Acid sequence Base sequence FLAGELLIN GENOTYPE Molecular sequence Data PHENOTYPE Protein Isoforms SALMONELLA Species Specificity
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Acute hepatitis C in a chronically HIV-infected patient:Evolution of different viral genomic regions 被引量:2
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作者 Diego Flichman Veronica Kott +1 位作者 Silvia Sookoian Rodolfo Campos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第7期1496-1500,共5页
AIM: To analyze the molecular evolution of different viral genomic regions of HCV in an acute HCV infected patient chronically infected with HIV through a 42-month follow-up.METHODS: Serum samples of a chronically HIV... AIM: To analyze the molecular evolution of different viral genomic regions of HCV in an acute HCV infected patient chronically infected with HIV through a 42-month follow-up.METHODS: Serum samples of a chronically HIV infected patient that seroconverted to anti HCV antibodies were sequenced, from the event of superinfection through a period of 17 months and in a late sample (42nd month). Hypervariable genomic regions of HIV (V3 loop of the gp120) and HCV (HVR-1 on the E2 glycoprotein gene) were studied. In order to analyze genomic regions involved in different biological functions and with the cellular immune response, HCV core and NS5A were also chosen to be sequenced. Amplification of the different regions was done by RT-PCR and directly sequenced. Confirmation of sequences was done on reamplified material. Nucleotide sequences of the different time points were aligned with CLUSTAL W 1.5, and the corresponding amino acid ones were deduced.RESULTS: Hypervariable genomic regions of both viruses (HVR1 and gp120 V3 loop) presented several nonsynonymous changes but, while in the gp120 V3 loop mutations were detected in the sample obtained right after HCV superinfection and maintained throughout, they occurred following a sequential and cumulative pattern in the HVR1. In the NS5A region of HCV, two amino acid changes were detected during the follow-up period, whereas the core region presented several amino acid replacements, once the HCV chronic infection had been established.CONCLUSION: During the HIV-HCV superinfection, each genomic region analyzed shows a different evolutionary pattem.Most of the nucleotide substitutions observed are nonsynonymous and clustered in previously described epitopes,thus suggesting an immune-driven evolutionary process. 展开更多
关键词 Acute Disease Adolescent Amino Acid sequence Female Genome Viral HIV HIV Envelope Protein gp120 HIV Infections HEPACIVIRUS Hepatitis C Humans Molecular sequence Data Research Support Non-U.S. Gov't SUPERINFECTION Viral Nonstructural Proteins Viral Proteins
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The expression and antigenicity identification of recombinant rat TGF-β1 in bacteria 被引量:1
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作者 GaoCF KongXT 《Cell Research》 SCIE CAS CSCD 2001年第2期95-100,共6页
In order to study structure-function details of TGF-beta1, the recombinant mature form of rat TGF-beta1 was expressed in bacteria. Synthesis of the 112 amino-acid carboxyl-terminal part of TGF-beta1 (amino acid 279-39... In order to study structure-function details of TGF-beta1, the recombinant mature form of rat TGF-beta1 was expressed in bacteria. Synthesis of the 112 amino-acid carboxyl-terminal part of TGF-beta1 (amino acid 279-390) was controlled by an inducible gene expression system based on bacteriophage T7 RNA polymerase. This system allowed an active and selective synthesis of recombinant TGF-beta1. The molecular weight of expressed TGF-alpha1 monomer determined on SDS-polyacrylamide gel under reducing conditions was about 13 kD. Serial detergent washes combined with a single gel-filtration purification step were sufficient to purify the expression product to homogeneity. Amino-terminal sequencing revealed that the N-terminal of the recombinant protein was identical to the published data. In Western blot analysis the recombinant polypeptide showed excellent antigenicity against polyclonal TGF-beta1 antibody. The mature recombinant rat TGF-beta1 expressed in this study provides a useful tool for future detailed structural and functional studies. 展开更多
关键词 Amino Acid sequence Animals Base sequence EPITOPES Escherichia coli Gene Expression Regulation Bacterial Genetic Vectors Molecular sequence Data Plasmids Protein Structure Tertiary Rats Recombinant Proteins Research Support Non-U.S. Gov't Transformation Genetic Transforming Growth Factor beta
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The point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province,a non HCC prevalent area in China 被引量:13
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作者 LiuH WangY 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期480-482,共3页
AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of C... AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of China, these factors are not so important in the etiology of HCC. Therefore, the point mutation of p53 exon7 may also be different than that in HCC-prevalent areas of China. The aim of this study is to investigate the status and carcinogenic role of the point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province, a non-HCC-prevalent area in China. METHODS: PCR PCR-SSCP and PCR-RFLP were applied to analyze the homozygous deletion and point mutation of p53 exon7 in HCC samples from Anhui, which were confirmed by DNA sequencing and Genbank comparison. RESULTS: In the 38 samples of hepatocellular carcinoma, no homozygous deletion of p53 exon7 was detected and point mutations of p53 exon7 were found in 4 cases, which were found to be heterozygous mutation of codon 249 with a mutation rate of 10.53%(4/38). The third base mutation(G-T) of p53 codon 249 was found by DNA sequencing and Genbank comparison. CONCLUSION: The incidence of point mutation of p53 codon 249 is lower in hepatocellular carcinoma and the heterozygous mutation of p53 exon7 found in these patients only indicate that they have genetic susceptibility to HCC. p53 codon 249 is a hotspot of p53 exon7 point mutation, suggesting that the point mutation of p53 exon 7 may not play a major role in the carcinogenesis of HCC in Anhui Province, a non-HCC-prevalent area in China. 展开更多
关键词 Genes p53 Base sequence Carcinoma Hepatocellular China DNA Neoplasm EXONS Humans Liver Neoplasms Molecular sequence Data Point Mutation Polymerase Chain Reaction Polymorphism Restriction Fragment Length Polymorphism Single-Stranded Conformational Research Support Non-U.S. Gov't sequence Homology Nucleic Acid
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Fecal microbiome of growing pigs fed a cereal based diet including chicory(Cichorium intybus L.) or ribwort(Plantago lanceolata L.) forage 被引量:1
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作者 Johan Dicksved Janet K.Jansson Jan Erik Lindberg 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2016年第2期167-175,共9页
Background: The purpose of this study was to investigate how inclusion of chicory forage or ribwort forage in a cereal-based diet influenced the fecal microbial community(microbiome) in newly weaned(35 days of age... Background: The purpose of this study was to investigate how inclusion of chicory forage or ribwort forage in a cereal-based diet influenced the fecal microbial community(microbiome) in newly weaned(35 days of age) piglets.The piglets were fed a cereal-based diet without(B) and with inclusion(80 and 160 g/kg air-dry forage) of vegetative shoots of chicory(C) and leaves of ribwort(R) forage in a 35-day growth trial. Fecal samples were collected at the start(D0), 17(D17) and 35(D35) days after weaning and profiles of the microbial consortia were generated using terminal restriction fragment length polymorphism(T-RFLP). 454-FLX pyrosequencing of 16 S r RNA gene amplicons was used to analyze the microbial composition in a subset of the samples already analyzed with T-RFLP.Results: The microbial clustering pattern was primarily dependent on age of the pigs, but diet effects could also be observed. Lactobacilli and enterobacteria were more abundant at D0, whereas the genera Streptococcus, Treponema,Clostridium, Clostridiaceae1 and Coprococcus were present in higher abundances at D35. Pigs fed ribwort had an increased abundance of sequences classified as Treponema and a reduction in lactobacilli. However, the abundance of Prevotellaceae increased with age in on both the chicory and the ribwort diet. Moreover, there were significant correlations between the abundance of Bacteroides and the digested amount of galactose, uronic acids and total non-starch polysaccharides, and between the abundance of Bacteroidales and the digested amount of xylose.Conclusion: This study demonstrated that both chicory and ribwort inclusion in the diet of newly weaned pigs influenced the composition of the fecal microbiota and that digestion of specific dietary components was correlated with species composition of the microbiota. Moreover, this study showed that the gut will be exposed to a dramatic shift in the microbial community structure several weeks after weaning. 展开更多
关键词 Amplicon sequencing Chicory Microbiome Ribwort Uronic acid Weaning 16S
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Insights into the phylogeny of sporadotrichid ciliates (Protozoa, Ciliophora: Hypotricha) based on genealogical analyses of multiple molecular markers
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作者 胡晓燕 胡晓钟 +2 位作者 Khaled A.S.AL-RASHEID Saleh A.AL-FARRAJ 宋微波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第1期96-102,共7页
The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent... The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent classification is still lacking and several important questions about the phylogenetic relationships within this group remain unsolved. To improve our understanding of these relationships, we constructed phylogenetic trees using the nucleotide sequences of the small-subunit rRNA (SSrRNA) gene and amino acid sequences of actin I and α-tubulin. Analyses of SSrRNA gene sequences indicated that: 1) the Sporadotrichida sensu Lynn (2008) and the Oxytrichidae are polyphyletic; 2) the Uroleptus species, which are classified to urostylids, formed a sister group with the oxytrichids; 3) Halteria grandinella, which is grouped morphologically with oligotrich species, clustered within the oxytrichids. These results are congruent with previous studies based on SSrRNA gene sequences. However, the amino acid sequences of actin I and α-tubulin yielded different topologies. The main results are: 1) in all phylogenetic trees, the genus Oxytricha was paraphyletic; 2) Uroleptus was sister to a subset of Urostyla and Holosticha, albeit with low supporting values; 3) Halteria grandinella was separated distantly from the Oxytrichidae in trees inferred from actin I amino acid sequences but clustered with oligotrichids in the α-tubulin analysis. The inconsistency among the trees inferred from these different molecular markers may be caused by rapidly accumulated genetic characterizations of ciliates. Further studies with additional molecular markers and sampling of more taxa are expected to better address the relationships among sporadotrichids. 展开更多
关键词 sporadotrichid ciliates PHYLOGENY SSRRNA actin I ALPHA-TUBULIN amino acid sequences
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