RESUMO
The study is aimed to ensure the quality and safety of medicinal plants by using ITS2 DNA barcode technology to identify Corydalis boweri, Meconopsis horridula and their close related species. The DNA of 13 herb samples including C. boweri and M. horridula from Lhasa of Tibet was extracted, ITS PCR were amplified and sequenced. Both assembled and web downloaded 71 ITS2 sequences were removed of 5. 8S and 28S. Multiple sequence alignment was completed and the intraspecific and interspecific genetic distances were calculated by MEGA 5.0, while the neighbor-joining phylogenetic trees were constructed. We also predicted the ITS2 secondary structure of C. boweri, M. horridula and their close related species. The results showed that ITS2 as DNA barcode was able to identify C. boweri, M. horridula as well as well as their close related species effectively. The established based on ITS2 barcode method provides the regular and safe detection technology for identification of C. boweri, M. horridula and their close related species, adulterants and counterfeits, in order to ensure their quality control, safe medication, reasonable development and utilization.
Assuntos
Sequência de Bases , China , Corydalis , Química , Classificação , Genética , Código de Barras de DNA Taxonômico , Métodos , DNA de Plantas , Química , Genética , DNA Espaçador Ribossômico , Química , Genética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Papaveraceae , Química , Classificação , Genética , Filogenia , Plantas Medicinais , Química , Classificação , GenéticaRESUMO
The discovery of microRNAs (miRNAs) has introduced a new paradigm into gene regulatory systems. Since inception, computational methods have been an invaluable tool complementing experimental approaches, and many discoveries have been obtained through combination of experimental and computational approaches. The knowledge that has been accumulated about the principles of miRNAs and target recognition were reviewed. The currently available computational methodologies and software for prediction of miRNA and their target genes also have been discussed.
RESUMO
The discovery of microRNAs (miRNAs) has introduced a new paradigm into gene regulatory systems. Since inception, computational methods have been an invaluable tool complementing experimental approaches, and many discoveries have been obtained through combination of experimental and computational approaches. The knowledge that has been accumulated about the principles of miRNAs and target recognition were reviewed. The currently available computational methodologies and software for prediction of miRNA and their target genes also have been discussed.
RESUMO
Nature is abundant in protein scaffolds.By selecting suitable protein scaffold,display and screening methods,the rational and constrained random peptide library(RPL)can be constructed.Compared with the non-constrained RPL,it offered more opportunities for obtaining novel protein structures and more higher affinity ligands against the target molecules.At present,the protein scaffold constrained RPLs have been shown great potential in applications such as target selection,basic research,clinical diagnosis,medical therapy and so on.It is systematically introduced the structure bases,classification and construction of constrained RPL based on scaffolds,as well the recent great advances of application in selection against target molecules with S-S constrained scaffolds,antibodies,Zinc finger protein,Z domain,FN3 domain as important examples.
RESUMO
<p><b>OBJECTIVE</b>To establish an improved procedure for isolation and identification of epitopes from a random peptide library displayed on the bacterial surface.</p><p><b>METHODS</b>Epitopes were screened from FliTrx random peptide library by a monoclonal antibody 3B9 against HBV-PreS2 protein. The enrichment was monitored in each round. Higher affinity clones were obtained by increasing the washing strength and randomly selected for sequencing and Western blot analysis.</p><p><b>RESULTS</b>Clones specifically binding to antibody were enriched in each round. Ten sequences were obtained from sixteen sequenced clones, seven of them contained the common motif RXRGXY with high homogeneity to 135-140 amio acids in HBV-PreS protein and have positive results in Western blot analysis. The other three sequences have no typical motif RXRGXY and showed different Western blot results.</p><p><b>CONCLUSIONS</b>It's easy and quick to drive epitopes from a random peptide library displayed on the bacterial surface.</p>
Assuntos
Animais , Sequência de Aminoácidos , Antígenos Virais , Alergia e Imunologia , Proteínas de Bactérias , Alergia e Imunologia , Flagelina , Alergia e Imunologia , Antígenos de Superfície da Hepatite B , Genética , Alergia e Imunologia , Epitopos Imunodominantes , Alergia e Imunologia , Dados de Sequência Molecular , Biblioteca de Peptídeos , Precursores de Proteínas , Genética , Alergia e ImunologiaRESUMO
Selection and affinities of Cd binding peptides were assayed by phage random dodecapeptide library and affinity chromatography. Two Cd binding peptides were obtained, it was found that the affinities of Cu~ 2+ ,Co~ 2+ ,Zn~ 2+ ,Ni~ 2+ for Cd binding peptides were higher than that of Cd~ 2+ and Cr~ 2+ after detection of the amplified Cd binding peptides displayed phages to different heavy metal-charged resins; the detoxification of E.coli to Ni~ 2+ and Cd~ 2+ was enhanced when infected by Cd binding peptide displayed phages as compared with those of the control. The interaction of Cd binding peptide displayed phages with heavy metals charged resins was also observed under microscope. The work would be of great value and consequences for the study of interaction between heavy metals and proteins(peptides), as well as thedetoxification and bioremediation of heavy metals.