Comprehensive Characterization of Anti-CTLA4 Monoclonal Antibody by Liquid Chromatography High Resolution Mass Spectrometry / 中国药学杂志

OBJECTIVE: To establish a mass spectrometry method for the qualitative analysis of anti-CTLA4 monoclonal antibody and its N-linked glycosylation. METHODS The anti-CTLA4 monoclonal antibody was characterized by liquid-mass technique from the aspects of intact molecular weight, subunit molecular weight, amino acid sequence coverage, disulfide bond, N-linked glycosylation site and glycoform. RESULTS: The molecular weight of anti-CTLA4 mAb (A2G0F/A2G0F) is 147 992; the deglycosylation molecular weight of anti-CTLA4 mAb is 145 103; the molecular weight of light chain is 23 450; the molecular weight of heavy chain (A2G0F) is 50 548; the heavy chain Fd segment has a molecular weight of 25 355 and the heavy chain sFc segment (A2G0F,1xK_Loss) has a molecular weight of 25 189. Peptide mapping was performed with Trypsin & Chymotrypsin, and the coverage of the amino acid sequence was 100%. The peptide containing the N-linked glycosylations site is EEQYNSTYR, and the N-glycosylation site is located at Asn298 of the heavy chains. Thirteen glycoform were characterized including A2G0F(59.8%), A2G1Fa(18.66%), A2G1Fb(7.28%), A2G2F(3.2%), M5(1.66%), A2S1G0F(1.17%), A1G0F (1.16%), A3G1F(0.95%), A2G0(0.94%), A2S2F(0.78%), A2S1G1F(0.67%), A3G0F(0.53%)and A1G1F(0.51%). CONCLUSION: A method for qualitative and quantitative analysis of monoclonal antibody is established.

Prediction of Metal Ion Binding Sites in Proteins from Amino Acid Sequences by Using Simplified Amino Acid Alphabets and Random Forest Model

Metal binding proteins or metallo-proteins are important for the stability of the protein and also serve as co-factors in various functions like controlling metabolism, regulating signal transport, and metal homeostasis. In structural genomics, prediction of metal binding proteins help in the selection of suitable growth medium for overexpression’s studies and also help in obtaining the functional protein. Computational prediction using machine learning approach has been widely used in various fields of bioinformatics based on the fact all the information contains in amino acid sequence. In this study, random forest machine learning prediction systems were deployed with simplified amino acid for prediction of individual major metal ion binding sites like copper, calcium, cobalt, iron, magnesium, manganese, nickel, and zinc.

Sequence similarity between thyroid self-protein and hepatitis c virus polyprotein: possible triggering mechanism of autoimmune thyroiditis / Similaridade de sequências entre auto-proteínas da tireoide e poliproteínas do vírus da hepatite C: possível mecanismo de desencadeamento da tireoidite auto-imune

ABSTRACT Background - Exposure to viral antigens that share amino acid sequence similar with self- antigens might trigger autoimmune diseases in genetically predisposed individuals, and the molecular mimicry theory suggests that epitope mimicry between the virus and human proteins can activate autoimmune disease. Objective - The purpose of this study is to explore the possible sequence similarity between the amino acid sequences of thyroid self-protein and hepatitis C virus proteins, using databanks of proteins and immunogenic peptides, to explain autoimmune thyroid disease. Methods - Were performed the comparisons between the amino acid sequence of the hepatitis C virus polyprotein and thyroid self-protein human, available in the database of National Center for Biotechnology Information on Basic Local Alignment Search Tool. Results - The sequence similarity was related each hepatitis C virus genotype to each thyroid antigen. The similarities between the thyroid and the viral peptides ranged from 21.0 % (31 identical residues out of 147 amino acid in the sequence) to 71.0% (5 identical residues out of 7 amino acid in the sequence). Conclusion - Bioinformatics data, suggest a possible pathogenic link between hepatitis C virus and autoimmune thyroid disease. Through of molecular mimicry is observed that sequences similarities between viral polyproteins and self-proteins thyroid could be a mechanism of induction of crossover immune response to self-antigens, with a breakdown of self-tolerance, resulting in autoimmune thyroid disease.

RESUMO Contexto - A exposição a antígenos virais que compartilham sequência de aminoácidos semelhantes a auto-antígenos pode provocar doenças auto-imunes em indivíduos predispostos geneticamente, e a teoria do mimetismo molecular sugere que o mimetismo entre epítopos de vírus e proteínas humanas pode ativar doenças auto-imunes. Objetivo - O objetivo deste estudo foi explorar a possível semelhança entre as sequências de aminoácidos de auto-proteinas da tireóide e proteínas do vírus da hepatite C, utilizando bancos de dados de proteínas e peptídeos imunogênicos, para explicar a doença auto-imune da tireóide. Métodos - Foram realizadas comparações entre as sequências de aminoácidos de poliproteínas do vírus da hepatite C e auto-proteinas da tireóide humana, disponível na base de dados do National Center for Biotechnology Information no Basic Local Alignment Search Tool. Resultados - A semelhança de sequências foi relacionada para cada genótipo de vírus da hepatite C e proteínas da tireóide. As semelhanças entre proteínas da tireóide e os peptídeos virais variaram de 21,0% (31 resíduos idênticos da sequência de 147 aminoácidos) a 71,0% (cinco resíduos idênticos da sequência de 7 aminoácidos). Conclusão - Dados de bioinformática sugerem uma possível ligação entre vírus da hepatite C e doença auto-imune da tireóide. Através de mimetismo molecular observa-se que as semelhanças entre as sequências de poliproteínas virais e auto-proteínas da tireóide pode ser um mecanismo de indução de resposta imune resultando em doença auto-imune da tireóide.

Evaluation of recombinant human interleukin-15 reference standard / 中国药学杂志

OBJECTIVE: To evaluate the reference standard of recombinant human interleukin-15 (IL-15) for the effective quality control of IL-15 products according to the requirements of Chinese Pharmacopeia. METHODS: The biological activity, concentration, purity, and isoelectric point of IL-15 were tested according to Chinese Pharmacopeia (volume III, 2010 edition). The primary structure was confirmed by analyzing the N-terminal amino acid sequence and relative molecular mass and peptide mass mapping. RESULTS: The measured biological activity of IL-15 was 1.03×107 IU·mg-1, the content was (0.879±0.065) mg·mL-1, the purities tested by SDS-PAGE and SEC-HPLC were all 100%, and the isoelectric point was 5.2, which all met the criteria specified in the quality standard. The observed relative molecular mass, 12 900.80, was consistent with theoretical value (12 900.71). Its amino acid sequence was verified with coverage of 100%. The disulfide bonds were identified to to be Cys36-Cys86/Cys43-Cys89, which was in accordance with the published papers. CONCLUSION: This reference standard, which is qualified and has correct amino acid sequence, can be used for the routine quality control of IL-15.

Construction and identification of recombinant human neutrophil gelatinase-associated lipo1calinlinear multi-epitope peptide / 中华检验医学杂志

Objective The feasibility of predicting the B-cell epitopes of human Neutrophil Gelatinase-Associated Lipocalin (NGAL) was discussed by applicating bioinformatics technology.Linear epitope molecules that have diagnostic value were screened and these recombinant linear multi-epitope peptides were constructed,and expressed.The immunogenicity of the recombinant linear multi-epitope peptides were also identified.Methods NGAL amino acid sequence was got from GenBank in the Department of Clinical Laboratory of the Second Affiliated Hospital of Nanjing Medical University in July 2015,the Predicted,ABCpred,BepiPred,BcePred,and Lasergene softwares were used to predict the linear B cell epitope prediction.The predict epitopes were constructed and prokaryotic expressed,and then the single epitope antigens which could reacted with commercially available polyclonal NGAL antibody were screened out by Western blot.Finally,the multi-epitope peptide was constructed,expressed,and identified through immunoreactions.Results Eight possible epitopes were obtained after prediction.pET32a-N1-N8 prokaryotic expression vector were used to express the predict epitopes.After purification and Western blot analysis,three of the epitopes have strong antigenicity,and then a soluble fusion protein was expressed and obtained from the multi-epitope prokaryotic expression vector pET22b-Ngal_MEP1.The fusion protein was successfully purified by Ni2 + affinity column.Western blot analysis showed that the fusion protein had a strong antigenicity.Conclusions The constructed multi-epitope linear NGAL antigen peptides can obtain high soluble expression in prokaryotic expression system,and have a strong immunoreactivity,which can be used in subsequent antibody preparation.

Analysis of GJA3 mutation associated with a Chinese family with autosomal dominant congenital cataract by whole-exome sequencing / 中华实验眼科杂志

Congenital cataract is one of the important reasons for the blindness of children,and most congenital cataracts are genetic.At present,thirty-nine genes have been identified relating to autosomal dominant congenital cataract (ADCC).Objective This study was to identify and analyze the virulence gene of a Chinese family pedigree with ADCC by whole-exome sequencing.Methods A Chinese ADCC family was recruited in Affiliated First Hospital of Zhengzhou University from August to September in 2014.The family disease history and clinical data were recorded.The peripheral venous blood of 10 ml was collected in 14 patients with congenital cataract and 14 families with normal phenotype,and the peripheral blood samples were obtained from 100 healthy examined people as controls.The genomic DNA was extracted form all subjects using standard phenol chlorum method,and proband DNA was screened by whole-exome sequencing.Then mutation locus of the candidate gene was selected after compared with the information of database in the proband.The mutation locus of the candidate gene from 14 normal families and 100 healthy controls were amplified and sequenced by PCR technique based on the primer sequence of mutation locus of proband to verify the pathogenic gene of this ADCC family.This study protocol was approved by Ethic Committee of Affiliated First Hospital of Zhengzhou University and complied with Helsinki Declaration.Written informed consent was obtained from subjects or custodian before any medical examination.Results The family had a total of 5 generations of 68 members,in which 20 subjects were found with congenital cataract.The inheritance mode consisted with autosomal dominant inheritance.Cortical cataract was found in both eyes in the patients.Whole-exome sequencing showed that the 143rd ribonucleotide A of exon 2 explicit factor of chromosome 13 GJA3 gene mutated into G (c.143A＞G) in the proband,which resulted in the 48th amino acids changed from glutamate into glycine (p.E48G).PCR amplification product sequencing displayed that the same mutation of DNA appeared in all the patients of this family,while not the same mutation was seen in the candidate genes of normal phenotype families and 100 healthy controls.Conclusions GJA3 gene c.143A＞G is a virulence mutation site in this ADCC family,it is a supplement of the mutation spectrum of GJA3 gene.

Primary structure of nuclease-like proteins from Eisenia foetida / 中国组织工程研究

BACKGROUND:A group of nuclease-like proteins were previously purified from Eisenia foetida tissues, exploring primary structures of these proteins wil help to uncover basic structure characteristics of them and provide foundations for the study addressing the relationship of their structures and functions. OBJECTIVE:To explore primary structures of nuclease-like proteins EWD1 and EWD2. METHODS:Edman degradation method was used to sequence the N-terminal amino acids of EWD1 and EWD2, acid hydrolisis method was used to analyze amino acid compositions of EWD1 and EWD2, LC-MS/MS was used to analyze some peptide sequences within the proteins, and MALDI-TOF-MS was used to calculate the number of the disulfide bonds and the contents of polysaccharides. RESULTS AND CONCLUSION:Among the amino acid compositions in EWD1 and EWD2, the sum contents of aspartate and asparagines were the highest (al nearly 10%), the contents of hydrophobic amino acids were also high, and the contents of cysteine was low. The EWD1 and EWD2 had similar amino acid compositions with other nucleases. Edman degradation results showed that, the N-terminal sequences of the large subunit of EWD1 were in turn as fol ows:D, E, W, V, Y, P;the N-terminal sequences of EWD2 were as fol ows:L, L, G, P, Y, K, P, K, C. The results of LC-MS/MS indicated the two proteins were novel proteins;MALDI-TOF-MS results showed that 8 cysteine residues formed 4 disulfide bonds in EWD1, 6 cysteine residues formed 3 disulfide bonds in EWD2. EWD1 and EWD2 were al glycoproteins, the content of polysaccharides was 17.3%in EWD1 and 15.6%in EWD2.

The Effect of Amino Acid Configuration on the Biodistribution of Peptide Nanofiber / 天津医药

Objective To compare the biodistribution difference of peptide nanofibers, which were self-assembled by peptide composed of L-or D-amino acids, respectively, and provide the guidance for the in vivo applications of peptide nanofibers. Methods The Nap-GFFYGRGD (L-peptide) and Nap-GDFDFDYGRGD (D-peptide, F and Y were D-configura-tion) were synthesized with solid phase peptide synthesis (SPPS). The structure of the two peptides was identified by nuclear magnetic resonance spectroscopy (1H NMR) and high-resolution mass spectrometry (HR-MS). The two peptides could self-assemble into nanofibers during the cooling process after being boiled. The morphology of the nanofibers was observed with transmission electron microscope (TEM). The peptides were radiolabeled with iodine-125 and self-assembled into nanofi-bers, which were then administered into BALB/c mice via tail vein. The blood samples were collected and then mice were sacrificed at 1, 3, 6 and 12 hours. The main organs (heart, liver, spleen, lung, kidney, stomach, large intestine, small intes-tine, muscle and brain) were isolated and weighed. The radioactivity of organs was detected with a gamma counter. Results The two peptides could self-assemble into nanofibers with diameter of 10-20 nanometers. There were no significant differ-ences in the diameter and morphology between two naofibers. There was significant difference in the biodistribution between two nanofibers. The blood concentration of D-fiber was (8.17±0.32)%ID/g at one hour after injection and then cleared rapid-ly from the blood. The blood concentration of L-fiber was (5.96±0.30)%ID/g at one hour after injection and maintained at a stable level for six hours. The L-fiber was mainly distributed in stomach while the D-fiber was mainly accumulated in liver. Conclusion The configuration of amino acids (D/L) could affect the biodistribution of peptide nanofibers dramatically, which may provide the guidance for the medical applications of peptide nanofibers.

Modeling and analysis of Schistosoma Argonaute protein molecular spatial conformation

<p><b>OBJECTIVE</b>To analyze the amino acid sequence composition, secondary structure, the spatial conformation of its domain and other characteristics of Argonaute protein.</p><p><b>METHODS</b>Bioinformatics tools and the internet server were used. Firstly, the amino acid sequence composition features of the Argonaute protein were analyzed, and the phylogenetic tree was constructed. Secondly, Argonaute protein's distribution of secondary structure and its physicochemical properties were predicted. Lastly, the protein functional expression form of the domain group was established through the Phyre-based analysis on the spatial conformation of Argonaute protein domains.</p><p><b>RESULTS</b>593 amino acids were encoded by Argonaute protein, the phylogenetic tree was constructed, and Argonaute protein's distribution of secondary structure and its physicochemical properties were obtained through analysis. In addition, the functional expression form which comprised the N-terminal PAZ domain and C-terminal Piwi domain for the Argonaute protein was obtained with Phyre.</p><p><b>CONCLUSIONS</b>The information relationship between the structure and function of the Argonaute protein can be initially established with bioinformatics tools and the internet server, and this provides the theoretical basis for further clarifying the function of Schistosoma Argonaute protein.</p>

Analysis of genetic diversity and amino acid sequence of HIV-1 tat from a patient with AIDS dementia complex / 中华微生物学和免疫学杂志

Objective To study the variation and characteristics of HIV-1 tat exon 1 gene from a patient with AIDS dementia complex( ADC), so as to research the pathogenesis of ADC. Methods The tat gene was amplified with nested PCR from genomic DNA which was extracted from lymph node, spleen and different brain tissues( meninges, grey matter from frontal cortex, white matter from frontal cortex, temporal cortex and basal ganglia) of a patient who died of ADC. PCR products were cloned into the pGEM-T vector,after transformation and selection by ampicillin and blue/white spotting. Five of positive clones were sequenced. HIV-1 tat sequences were processed with BioEdit and MEGA4. With the softwares, Neighbor-Joining tree, p-Distances, values of ds/dn, and analysis of amino acid motifs were all done. Results The samples were all identified as HIV-1 B and genetic variation exists in HIV-1 tat isolated from different tissue;Compared with HXB2, sixteen sites of the amino acid seque nce coded by the HIV-1 tat gene which was isolated from the patient changed. In addition, part of the changes were different between periphery and brain,especially, the five Q54R changes from basal ganglia and one Q54R change from temporal cortex are deserve to follow with interest. Conclusion Variations exist in the HIV-1 tat genes extracted from the ADC patient and the variations from peripheral and central nerve tissues were different, whether the variations concerned with the pathogenesis of ADC need more research.

Modeling and analysis of Schistosoma Argonaute protein molecular spatial conformation

Objective: To analyze the amino acid sequence composition, secondary structure, the spatial conformation of its domain and other characteristics of Argonaute protein. Methods:Bioinformatics tools and the internet server were used. Firstly, the amino acid sequence composition features of the Argonaute protein were analyzed, and the phylogenetic tree was constructed. Secondly, Argonaute protein’s distribution of secondary structure and its physicochemical properties were predicted. Lastly, the protein functional expression form of the domain group was established through the Phyre-based analysis on the spatial conformation of Argonaute protein domains. Results: 593 amino acids were encoded by Argonaute protein, the phylogenetic tree was constructed, and Argonaute protein’s distribution of secondary structure and its physicochemical properties were obtained through analysis. In addition, the functional expression form which comprised the N-terminal PAZ domain and C-terminal Piwi domain for the Argonaute protein was obtained with Phyre. Conclusions: The information relationship between the structure and function of the Argonaute protein can be initially established with bioinformatics tools and the internet server, and this provides the theoretical basis for further clarifying the function of Schistosoma Argonaute protein.

Study on glycoprotein gene sequences of nine rabies virus isolates in Henan Province / 中华传染病杂志

Objective To understand the nucleotide and amino acid differences of glycoprotein gene (G gene) between isolated rabies viruses in Henan Province and rabies vaccine strains used for human and animals. Methods G gene sequences of nine rabies viruses isolated from dogs in Xinyang city of Henan Province in December 2006 were amplified by reverse transcriptase (RT)-heminestedpolymerase chain reaction (PCR), and then were cloned and sequenced. The phylogenetic trees were constructed for analyzing the genetic characteristics of these rabies viruses. Results The homology of G gene among the nine isolates from Henan Province was 97.6% - 98.9% at nucleotide level and 99.2%-99.8% at amino acid level. The similarities between these isolates and CTN vaccine strain were 85.6%-93.0% and 91.9%-92.9% at nucleotide and amino acid level, respectively, which were higher than those between these isolates and other vaccine strains (80.4% - 83.3% and 87.7% - 92.5% at nucleotide and amino acid level, respectively). The nine isolates had several amino acid substitutions when compared to other genotype 1 rabies virus strains. Conclusions The nine rabies viruses strains isolated from Henan Province all belong to genotype 1. CTN may be an effective vaccine for preventing rabies in Henan Province.

Physicochemical properties and biological activity of a recombinant inducible co-stimulator-Ig fusion protein / 第二军医大学学报

Objective: To investigate the physicochemical properties and biological activity of self-prepared fusion protein inducible co-stimulator-Ig. Methods: Acid hydrolysis, edman degradation and peptide mass finger printing were used to determine the amino acid composition, N-terminal 15 amino acid sequences, and peptide mapping. In vivo mixed lymphocyte reaction assay was used for identification of its biological activity. Results: The result of amino acids composition analysis was consistent with the theoretical value of ICOS-Ig. N-terminal 15 amino acid sequences of the product were EINGSANYEMFIFHN, consistent with the theoretical value of ICOS-Ig. Peptide match assay identified six peptides of the product which could match the theoretic maps of ICOS-Ig. ICOS-Ig and CsA noticeably inhibited the proliferation of allo-reactive T cells in vivo. Conclusion: The prepared ICOS-Ig fusion protein has a correct structure and can inhibit the proliferation of allogeneic T cells in vivo, which lays a foundation for quality control of ICOS-Ig fusion protein.

Purification and characterization of mycoferritin from Aspergillusflavus MTCC 873.

The fungus Aspergillus flavus MTCC 873, a non-toxigenic isolate demonstrated its capability to synthesize mycoferritin (MF) upon induction with iron in yeast extract sucrose (YES) medium. The molecular mass, yield, iron and carbohydrate contents of the MF were 440 kDa, 0.015 mg/g of wet mycelia, 0.8 and 30.4%, respectively. Native gel-electrophoresis revealed a band corresponding to dimeric form of equine spleen ferritin (ESF). Subunit analysis by SDS-PAGE revealed a single protein band with an apparent molecular mass of 24 kDa, suggesting similar sized subunits in the structure of apoferritin shell. Immunological cross-reactivity was observed with the anti-fish liver ferritin. Transmission electron microscopy (TEM) revealed an apparent particle size of 100 Å. N-terminal amino acid sequence of MF revealed a sequence of SLPLQDYA, which showed identities with other eukaryotic ferritin sequences. The spectral characteristics (UV/VIS, fluorescence and circular dichroic spectra) were similar to ESF. The fungus, unlike A. parasiticus 255 (non-toxigenic) was incapable of producing aflatoxins, when grown in YES media.

Identification and Characterization of Peptide Mimics of Blood Group A Antigen / 华中科技大学学报（医学）（英德文版）

In order to investigate peptide mimics of carbohydrate blood group A antigen, a phage display 12-met 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 QIWYERTLPFrF. 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 an- tigen and might be used as anti-A antibody-adsorbing materials when immunoabsorption was applied in ABO incompatible transplantation.

Study of sequencing of VP4, VP7, NSP1, NSP4 genes of human rotavirus strain G4P6 (2001019203)

Background: Rotavirus is the main cause of acute viral gastroenteritis in children under 5 years old. In Viet Nam, about 50-70% hospitalized children with acute diarrhea caused by rotavirus. This indicated the importance of vaccination against diarrhea in Vietnam and researching on creating safe diarrhea vaccine for infants was a imperative. To achieve a good result of the research, it\u2019s necessary to understand the genetic characteristics of rotavirus.Objectives: To determine sequencing of VP4, VP7, NSP1, NSP4 genes of human rotavirus strain G4P6. Subjects and method: The research was performed on rotavirus samples (203pp16TK; 203pp27TK; 203pp30vero; 203pp37vero; 203pp38vero lot11; 203pp38TK lot12) by using ARN separation and RT-PCR methods. Results and Conclusion: We presented the results of sequencing of VP4, VP7, NSP1, NSP4 genes in some passages of human rotavirus strain G4P6 including their deduced amino acid sequence. The nucleotide mutants of VP7, NSP4 genes of passages are 2, 1 respectively. All the mutants result in amino acid changes. There was no mutation on VP4, NSP1 genes. The result confirmed that all passages of human rotavirus strain G4P6 had no contamination. They had similar degree respectively 89-93%, 85-97%, 81-93%, 92-95% with strains in the world.

The relationship between amino-acid motif of HLA-DR?1*04(?chain) and the susceptibility to rheumatoid arthritis / 中华风湿病学杂志

Objective To investigate the susceptibility to rheumatoid arthritis (RA) with HLA- DR?1*04 subtypes.Methods One hundred and thirty-six RA patients and 79 patients with other rheumatic diseases were recruited in this study.HLA typing was performed using high-resolution PCR-SSP DNA techniques.The clinical features and serologic markers between different motifs were analyzed.Results Compared with other rheumatic diseases,the frequency of HLA-DR?1*04 alleles in RA patients was significantly increased(33.8% vs 12.7%)(OR=3.52,95%CI=1.43~5.43,P

Amino Acid Composition of the α Chain of Hemoglobin and Amino Acid Sequence of it′s Particular Peptide Fragment From 615 Mouse / 生物化学与生物物理进展

The α chain of hemoglobin of 615 mouse was isolated and purified on CM-Celullose-23 colomn chromatography. The N-terminal amino acid of the α chain was valine determined with DABITC/PITC method.The amino acid composition was determined and it was different from the parent(C57BL)in literature on the number of leucine residue,histine residue and valine residue.An undissoluble ‘core’ and dissoluble peptides were found when the α chain of 615 mouse was hydrolysised by trypsin and it was found that the eighth amino acid residue from N-terminal of one particular peptide fragment mutated from valine (C57BL) to leucine.

Mass spectrometry analysis of Schwann cell-derived neurotrophic protein / 中华显微外科杂志

Objective To analyse the molecular structure of Schwann cell derived neurotrophic protein (SDNP) by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI TOF MS) Methods The purity of SDNP was digested byTPCK trypsin and detected by MALDI TOF MS, mass mapping was determined and partial sequences of the protein have neen analyzed by the mass data of fragment ion peaks in the fragmentation analysis and structural TOF MS (FAST) spectra The primary partial structure of SDNP was identified by searching the protein databases Results The integrity SDNP in peak detected by MALDI TOF MS has 66?10 3 MW and higher purity, because no other peaks exists except double charge peak The mass mapping of many peptides was determined and 8 peptides of them have been retrieved in MS Fit database, there is not the same protein in database Hypothetical protein has 5 peptides homology with the sample (62%) FAST spectra of 2305 Da shows the primary partial structure of SDNP after searching the protein MS Tag database Conclusions The molecular weight of SDNP detected by MALDI TOF MS is 66?10 3, The sequence of partial amino acid is EPVKKVTNSRRAKRTKPNGHIAN

Partial Sequence Analysis of Puumala Virus M Segment from Bats in Korea

Hantavirus is a genus of the Bunyaviridae family causing two serious diseases, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). Puumala virus is a member of hantavirus originally found in Europe, and its natural reservoir is Clethrionomys glareolus. It is also associated with the hurnan disease nephropathia epidemica, a milder form of HFRS. To identify the hantaviruses in bats, bats were collected from Jeong-Sun, Won-Joo, Chung-Ju and Hwa-Cheon area in Korea, and nested RT-PCR was performed with serotype specific primer from M segment. Interestingly, Puumala virus was detected in bats (Rhinolophus ferrum-equinum) only from Won-Joo. The 327 bp nested RT-PCR product, was sequenced. The sequence database search indicates that the sequence is homologous to the published sequence of Puumala viruses. The sequence similarities were ranged from 71% to 97%. The highest sequence similarity was 97% with Puumala virus Vranicam strain, and the lowest was 71% with Puumala virus K27 isolate. Puumala virus Vranicam strain was isolated from a bank vole (Clethrionomys glareolus) in Bosnia-Hercegovina. Puumala virus K27 was isolated from human in Russia. This analysis confirms that bats (Rhinolophus ferrum-equinum) in Korea are natural reservoir of Puumala virus.