[Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper (Capsicum) hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Re...[Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper (Capsicum) hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Result] According to the polymorphism and heterozygosity, Hpms1-214, Es395 and Hpmsl-5 were determined as three preferred core primers for purity identification of pepper hybrids. By using these three preferred core primers, 97 pepper hybrids (accounting for 97%) had heterozygous band pattern with at least one primer. Es330, Es363, Epms923, Es120 and Es64 were determined as candidate core primers for purity identification of pepper hybrids. Specific primers of 14 varieties were obtained, which could be used to further screen parent-complementary primers of each pepper hybrid. [Con- clusion] This study laid the foundation for constructing standard DNA fingerprints for purity identification of pepper hybrids.展开更多
[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus (AIV) ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 su...[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus (AIV) ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 subtypes of AIV accessed in GenBank, and design primers( by Primer Premier 5.0) on high homologous region of these sequences, and then amplified by RT-PCR. [Result] The multiplex RT-PCR amplification, agarose gel electrophoresis and sequencing results showed that the self-designed primers are successful for detecting AIV. [Conclusion] It is feasible to rapidly diagnose AIV through this method.展开更多
Among many reports investigating microbial diversity from environmental samples with denaturing gradient gel electrophoresis (DGGE), limited attention has been given to the effects of universal primers and DNA extract...Among many reports investigating microbial diversity from environmental samples with denaturing gradient gel electrophoresis (DGGE), limited attention has been given to the effects of universal primers and DNA extraction on the outcome of DGGE analysis. In this study, these effects were tested with 16S rRNA gene-based DGGE on a bacterial community from farming water samples. The results indicate that the number of discernable bands in the DGGE fingerprint differed with the primer pairs used; the bands produced by 63f/518r, 341f/926r and 933f/1387r primer pairs were obviously fewer than those by 968f/1401r. Also, we found that each DNA extraction method resulted in different community profiles, reflected by the number and intensity of bands in the DGGE fingerprint. Furthermore, the main bands (theoretically representing dominant bacteria) differed with the extraction methods applied. It is therefore believed that the effects of universal primers and DNA extraction should be given more attention and carefully chosen before performing an investigation into a new environment with DGGE.展开更多
Tylenchulus semipenetrans is the most economically important and widespread nematode pest of citrus in China.rDNA-ITS of 14 populations of T.semipenetrans which were collected from different citrus groves or Chinese ...Tylenchulus semipenetrans is the most economically important and widespread nematode pest of citrus in China.rDNA-ITS of 14 populations of T.semipenetrans which were collected from different citrus groves or Chinese fir(Cunninghamia lanceolata) plantations in China were amplified and sequenced.The species-specific primers were designed for the first time to diagnosis T.semipenetrans based on the sequences of rDNA-ITS regions of geographic population above.The primers were sensitive to amplify the expected band size(297 bp) from DNA template of a single second-stage juvenile(J2) or different life stages of T.semipenetrans.No specific band was amplified from 15 non-target nematode species which were commonly found in citrus groves.Specificity and reliability of the primers were validated by further PCR amplification of 16 extra populations of T.semipenetrans collected from 4 provinces of China.The primers successfully detected a single J2 of T.semipenetrans within a whole nematode community comprising a large numbers of non-target nematode.The developed diagnostic technique can be used for accurate identification of T.semipenetrans and also as a decision tool for nematode management for citrus or Chinese fir in China.展开更多
Objective To provide a feasible and cost-effective next-generation sequencing (NGS) method for accurate identification of viral pathogens in clinical specimens, because enormous limitations impede the clinical use o...Objective To provide a feasible and cost-effective next-generation sequencing (NGS) method for accurate identification of viral pathogens in clinical specimens, because enormous limitations impede the clinical use of common NGS, such as high cost, complicated procedures, tremendous data analysis, and high background noise in clinical samples. Methods Viruses from cell culture materials or clinical specimens were identified following an improved NGS procedure: reduction of background noise by sample preprocessing, viral enrichment by barcoded oligonucleotide (random hexamer or non-ribosomal hexanucleotide) primer-based amplification, fragmentation-free library construction and sequencing of one-tube mixtures, as well as rapid data analysis using an in-house pipeline. Results NGS data demonstrated that both barcoded primer sets were useful to simultaneously capture multiple viral pathogens in cell culture materials or clinical specimens and verified that hexanucleotide primers captured as many viral sequences as hexamers did. Moreover, direct testing of clinical specimens using this improved hexanucleotide primer-based NGS approach provided further detailed genotypes of enteroviruses causing hand, foot, and mouth disease (HFMD) and identified other potential viruses or differentiated misdiagnosis events. Conclusion The improved barcoded oligonucleotide primer-based NGS approach is simplified, time saving, cost effective, and appropriate for direct identification of viral pathogens in clinical practice.展开更多
The globally invasive cassava mealybug Phenacoccus manihoti Matile-Ferrero is a pernicious pest of cassava,and its recent introduction into Asia has raised considerable alarm.To slow or prevent further invasion,an acc...The globally invasive cassava mealybug Phenacoccus manihoti Matile-Ferrero is a pernicious pest of cassava,and its recent introduction into Asia has raised considerable alarm.To slow or prevent further invasion,an accurate,simple,and developmental-stage-independent detection method for P.manihoti is required.In the present study,a PCR method based on a species-specific mitochondrial DNA cytochrome oxidase I(SS-COI)marker was developed for rapid identification of P.manihoti.One pair of SS-COI primers(PMSSZW-1F and PMSSZW-1R)was designed based on sequence variations in the COI gene among P.manihoti and related mealybug species.Specificity of the primer pair was validated on 21 closely related species.Sensitivity tests were performed on four immature developmental stages and female adults.Efficacy tests demonstrated that at the relatively low concentration of(135.2±14.7)pgresuspended DNA,the specific fragment was detected in all replicates.Furthermore,the SS-COI primer pair was assayed on three populations of P.manihoti from major exporting countries of cassava.The PCR assay was proved to be a rapid,simple,and reliable molecular measure for the identification of P.manihoti.This tool will be useful for quarantine,monitoring,and management of this invasive pest.展开更多
Peritrich ciliates are highly diverse and can be important bacterial grazers in aquatic ecosystems. Morphological identifi cations of peritrich species and assemblages in the environment are time-consuming and experti...Peritrich ciliates are highly diverse and can be important bacterial grazers in aquatic ecosystems. Morphological identifi cations of peritrich species and assemblages in the environment are time-consuming and expertise-demanding. In this study, two peritrich-specifi c PCR primers were newly designed to amplify a fragment including the internal transcribed spacer(ITS) region of ribosomal rDNA from environmental samples. The primers showed high specifi city in silico, and in tests with peritrich isolates and environmental DNA. Application of these primers in clone library construction and sequencing yielded exclusively sequences of peritrichs for water and sediment samples. We also found the ITS1, ITS2, ITS, D1 region of 28 S rDNA, and ITS+D1 region co-varied with, and generally more variable than, the V9 region of 18 S rDNA in peritrichs. The newly designed specifi c primers thus provide additional tools to study the molecular diversity, community composition, and phylogeography of these ecologically important protists in dif ferent systems.展开更多
In this paper, we took the lead in studying on specificity of the microsatellite DNA loci and applicability of mi crosatellite DNA primers in protozoa. In order to study characters of microsatellites in free living pr...In this paper, we took the lead in studying on specificity of the microsatellite DNA loci and applicability of mi crosatellite DNA primers in protozoa. In order to study characters of microsatellites in free living protozoa, eight microsatellite loci primers developed from Trypanosoma cruzi (MCLE01, SCLE10, MCLE08, SCLE11, MCLF10, MCLG10, MCL03, MCL05) were employed to amplify microsatellite in four free living protozoa, including Bodo designis, Euglena gracilis FACHB848, Paramecium bruzise and Tetrahymena thermophila BF1. In the amplification systems of P. bruzise, four loci (SCLE10, SCLE11, MCLF10, MCL03) were amplified successfully, and four amplification fragments were in proper size. In genome of E. gracilis FACHB848, five of eight primers brought five clear amplification bands. In B. designis, three (No.4, 5 and 7) of eight loci produced clear and sharp products without stutter bands, whereas no bands appeared in T. thermophila BF1. Further, eight 300-500 bp amplification fragments were cloned and sequenced. Nevertheless, all sequenced products did not contain corresponding microsatellite sequence, although Bodo is in the same order and has the nearest phylogenetic relation with Trypanosoma among these four species. Thus, the microsatellite DNA primers can not be applied among order or more far taxa, and the specificity of microsatellite DNA is very high in protozoa. The results of this study will contribute to our understanding of microsatellite DNA in protozoa.展开更多
The possibility of identifying gunshot residue (GSR) particles produced by non-toxic primers containing only titanium and zinc is a very difficult task using SEM/EDX analysis employed in the analysis of GSR originatin...The possibility of identifying gunshot residue (GSR) particles produced by non-toxic primers containing only titanium and zinc is a very difficult task using SEM/EDX analysis employed in the analysis of GSR originating from primers containing lead, barium and antimony. However, Bauer et al. demonstrated that non-toxic (TieZn) primers form a TiZn2O4 spinel crystalline structure using SEM/EDX with EBSD (Electron Back Scatter Diffraction) and TKD (Transmission Kikuchi Diffraction), whereas GSR originating from gadolinium-doped TieZn primers form a non-crystalline glass phase. Here, a possible explanation of these different phenomena is hypothesized.展开更多
Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biologica...Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biological samples.Methods:Strains were isolated,DNA extracted,and classified by using three Polymerase Chain Reactions(PCR).Subsequently this DNA was used along with other isolates of various biological samples,for a new PCR using primers designed.Finally,the amplified fragments were sequenced.Results:It was observed the predominance of DTU i in Colombia,as well as the specificity of our primers for detection of T.cruzi,while no band was obtained when other species were used.Conclusions:This work reveals the genetic variability of 21 new isolates of T.cruzi in Colombia.Our primers confirmed their specificity for detecting the presence of T.cruzi.展开更多
[ Objective ] The paper was to compare different extraction methods for genomie DNA of fall webworm [ Hyphantria cunea (Drury) ] and study the am- plification effect of different primers on sequences of CO I and CO ...[ Objective ] The paper was to compare different extraction methods for genomie DNA of fall webworm [ Hyphantria cunea (Drury) ] and study the am- plification effect of different primers on sequences of CO I and CO II and Cytb. [Method] With winter pupae of fall webworm as the test materials, genomic DNA of fall webworm were extracted by five different methods including CTAB method, SDS method, improved SDS method, kit method and different processing time. Six groups of different primers were used to amplify sequences of CO I and CO II and Cytb. [ Result~ Full DNA could be extracted by CTAB method, SDS method and improved SDS method, and the effort of low concentration SDS method was the best. Six groups of primers could amplify the corresponding fragment, and two groups of primers had the best effort for amplification of CO I . [ Conclusion] The study provides better methods for DNA extraction.展开更多
In the present study, one unique low-molecular-weight glutenin subunit (LMW-GS) gene. LMWXY22-2 (GenBank no. FJ028810), was isolated from wheat cultivar Xiaoyan 22 (Triticum aestivum L.) by a pair of genomic spe...In the present study, one unique low-molecular-weight glutenin subunit (LMW-GS) gene. LMWXY22-2 (GenBank no. FJ028810), was isolated from wheat cultivar Xiaoyan 22 (Triticum aestivum L.) by a pair of genomic specific PCR primers for 1B chromosome. Sequence analysis revealed that LMWXY22-2 was composed of 1 364 bp nucleotides, including a 317 bp promotion region and a 1 047 bp coding region which could be translated into a mature protein of 349 amino acids. In spite of a few minor mutations, the sequence of 5' untranslated region (UTR), the coding region, the deduced N- and Cterminus comparisons indicated that LMWXY22-2 belonged to the reported subunits of LMW-m type and type lII group 5, respectively. Inner gene markers for 1D chromosome together with the phylogenetic analysis revealed that this gene was classified into Glu-D3, which was not in agreement with the I B locus-specific primers for LMW genes completely.展开更多
Different results of seed purity identification for Gangyou 158, Ⅱ You 808, Wuyou 308 and Tianfengyou 316 were obtained using different SSR primers in our early work. To find out the reasons, the four hybrid combinat...Different results of seed purity identification for Gangyou 158, Ⅱ You 808, Wuyou 308 and Tianfengyou 316 were obtained using different SSR primers in our early work. To find out the reasons, the four hybrid combinations were grown in field to identify their purity according to their phenotypic traits. Then, the results of field identification were compared with that of laboratory tests using different SSR primers. The comparison revealed that only sterile lines (female parent) were distin- guished from true hybrids using the primers RM208, RM264, RM242 and RM164 for the purity identification of Gangyou 158, II You 808, Wuyou 308 and Tianfengyou 316, so the results were higher than that of field identification. In contrast, the primers RM341, RM297, RM21 and RM110 were able to distinguish not only the sterile plants but also the cross-pollinated ones from the true hybrids of Gangyou 158,Ⅱ You 808, Wuyou 308 and Tianfengyou 316, and the results of purity identifi- cation using them were close that of field identification, in summary, several pairs of primers should be used for the purity identification of rice hybrids to distinguish all the off-type plants and thus improve the accuracy.展开更多
[Objective]The paper was to establish a rapid identification method of Bactrocera cilifera(Hendel)with species-specific primers(SS-COI).[Method]Using B.cilifera(Hendel)as the positive control,and 19 species of fruit f...[Objective]The paper was to establish a rapid identification method of Bactrocera cilifera(Hendel)with species-specific primers(SS-COI).[Method]Using B.cilifera(Hendel)as the positive control,and 19 species of fruit flies such as B.diaphora(Coquillett)and B.dorsalis(Hendel)as the negative controls,a pair of species-specific primers,YF290 and YR511,were designed and screened for accurate identification of B.cilifera,based on mitochondrial DNA COI sequence.[Result]The PCR products were amplified and detected by electrophoresis.Only a clear and single band was observed at about 222 bp in the positive control,while no bands were found in the other negative controls.[Conclusion]The established rapid identification method with species-specific primers(SS-COI)is of great practical significance for rapid identification of fruit flies intercepted from import and export fruits and vegetables at ports,and for rapid clearance and early warning of import fruits and vegetables at ports.展开更多
The availability of the plastid genome sequences is one of the bases for comparative,functional,and structural genomic studies of plastid-containing living organisms,in addition to the application
In an effort to simplify the procedure and to reduce the cost of fluorescence SSR analysis, the conditions of the multiplex PCR and the multiplex gel electrophoresis were optimized in the genetic analysis of sunflower...In an effort to simplify the procedure and to reduce the cost of fluorescence SSR analysis, the conditions of the multiplex PCR and the multiplex gel electrophoresis were optimized in the genetic analysis of sunflower (Helianthus annuus L.) inbred lines. Results indicated that factors for a successful multiplex PCR assay were related to the cycling touchdown annealing temperature, the balance of primer concentration at the various loci, the concentration of PCR buffer and the Taq DNA polymerase. Based on the optimization, a tailed primer strategy was outlined, and the effective ways were proposed to overcome the troubleshootings commonly encountered in the multiplex PCR and the multiplex gel electrophoresis.展开更多
AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using ...AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.展开更多
基金Supported by Excellent Team Training Program of Yunnan Academy of Agriculture Sciences(YAAS2014YY002)~~
文摘[Objective] This study aimed to screen a set of SSR core primers suitable for purity identification of pepper (Capsicum) hybrids. [Method] DNA fingerprint of 100 pepper hybrids was analyzed using 17 SSR primers. [Result] According to the polymorphism and heterozygosity, Hpms1-214, Es395 and Hpmsl-5 were determined as three preferred core primers for purity identification of pepper hybrids. By using these three preferred core primers, 97 pepper hybrids (accounting for 97%) had heterozygous band pattern with at least one primer. Es330, Es363, Epms923, Es120 and Es64 were determined as candidate core primers for purity identification of pepper hybrids. Specific primers of 14 varieties were obtained, which could be used to further screen parent-complementary primers of each pepper hybrid. [Con- clusion] This study laid the foundation for constructing standard DNA fingerprints for purity identification of pepper hybrids.
基金Supported by Important Project of Jinlin Provincial Science and Technology Department(20065020)~~
文摘[Objective] The research aimed to design primers that are suitable for detecting H5 and H7 subtypes of avian influenza virus (AIV) ; [Method] DNAStar was used to analyze the homology of the sequences of H5 and H7 subtypes of AIV accessed in GenBank, and design primers( by Primer Premier 5.0) on high homologous region of these sequences, and then amplified by RT-PCR. [Result] The multiplex RT-PCR amplification, agarose gel electrophoresis and sequencing results showed that the self-designed primers are successful for detecting AIV. [Conclusion] It is feasible to rapidly diagnose AIV through this method.
基金This work was funded by the Special Scientific Foundation of Guangdong Province (No. A305030301)was partly supported by a grant from KLFEE, Ministry of Agriculture (2003-04).
文摘Among many reports investigating microbial diversity from environmental samples with denaturing gradient gel electrophoresis (DGGE), limited attention has been given to the effects of universal primers and DNA extraction on the outcome of DGGE analysis. In this study, these effects were tested with 16S rRNA gene-based DGGE on a bacterial community from farming water samples. The results indicate that the number of discernable bands in the DGGE fingerprint differed with the primer pairs used; the bands produced by 63f/518r, 341f/926r and 933f/1387r primer pairs were obviously fewer than those by 968f/1401r. Also, we found that each DNA extraction method resulted in different community profiles, reflected by the number and intensity of bands in the DGGE fingerprint. Furthermore, the main bands (theoretically representing dominant bacteria) differed with the extraction methods applied. It is therefore believed that the effects of universal primers and DNA extraction should be given more attention and carefully chosen before performing an investigation into a new environment with DGGE.
基金supported by the National Natural Science Foundation of China (30700526)the Postdoctoral Science Foundation of China (55920)the Science Foundation of the Fujian Province,China (2009N0013)
文摘Tylenchulus semipenetrans is the most economically important and widespread nematode pest of citrus in China.rDNA-ITS of 14 populations of T.semipenetrans which were collected from different citrus groves or Chinese fir(Cunninghamia lanceolata) plantations in China were amplified and sequenced.The species-specific primers were designed for the first time to diagnosis T.semipenetrans based on the sequences of rDNA-ITS regions of geographic population above.The primers were sensitive to amplify the expected band size(297 bp) from DNA template of a single second-stage juvenile(J2) or different life stages of T.semipenetrans.No specific band was amplified from 15 non-target nematode species which were commonly found in citrus groves.Specificity and reliability of the primers were validated by further PCR amplification of 16 extra populations of T.semipenetrans collected from 4 provinces of China.The primers successfully detected a single J2 of T.semipenetrans within a whole nematode community comprising a large numbers of non-target nematode.The developed diagnostic technique can be used for accurate identification of T.semipenetrans and also as a decision tool for nematode management for citrus or Chinese fir in China.
基金supported by the China Mega-Project for Infectious Disease(2016ZX10004-101,2016ZX10004-215)Beijing Municipal Science&Technology Commission Project(D151100002115003)Guangzhou Municipal Science&Technology Commission Project(2015B2150820)
文摘Objective To provide a feasible and cost-effective next-generation sequencing (NGS) method for accurate identification of viral pathogens in clinical specimens, because enormous limitations impede the clinical use of common NGS, such as high cost, complicated procedures, tremendous data analysis, and high background noise in clinical samples. Methods Viruses from cell culture materials or clinical specimens were identified following an improved NGS procedure: reduction of background noise by sample preprocessing, viral enrichment by barcoded oligonucleotide (random hexamer or non-ribosomal hexanucleotide) primer-based amplification, fragmentation-free library construction and sequencing of one-tube mixtures, as well as rapid data analysis using an in-house pipeline. Results NGS data demonstrated that both barcoded primer sets were useful to simultaneously capture multiple viral pathogens in cell culture materials or clinical specimens and verified that hexanucleotide primers captured as many viral sequences as hexamers did. Moreover, direct testing of clinical specimens using this improved hexanucleotide primer-based NGS approach provided further detailed genotypes of enteroviruses causing hand, foot, and mouth disease (HFMD) and identified other potential viruses or differentiated misdiagnosis events. Conclusion The improved barcoded oligonucleotide primer-based NGS approach is simplified, time saving, cost effective, and appropriate for direct identification of viral pathogens in clinical practice.
基金supported by the National Key R&D Program of China(2017YFC1200600,2016YFC1201200 and 2015BAD08A16)the Science and Technology Innovation Program of CAAS(caascx-2013-2018-IAS)
文摘The globally invasive cassava mealybug Phenacoccus manihoti Matile-Ferrero is a pernicious pest of cassava,and its recent introduction into Asia has raised considerable alarm.To slow or prevent further invasion,an accurate,simple,and developmental-stage-independent detection method for P.manihoti is required.In the present study,a PCR method based on a species-specific mitochondrial DNA cytochrome oxidase I(SS-COI)marker was developed for rapid identification of P.manihoti.One pair of SS-COI primers(PMSSZW-1F and PMSSZW-1R)was designed based on sequence variations in the COI gene among P.manihoti and related mealybug species.Specificity of the primer pair was validated on 21 closely related species.Sensitivity tests were performed on four immature developmental stages and female adults.Efficacy tests demonstrated that at the relatively low concentration of(135.2±14.7)pgresuspended DNA,the specific fragment was detected in all replicates.Furthermore,the SS-COI primer pair was assayed on three populations of P.manihoti from major exporting countries of cassava.The PCR assay was proved to be a rapid,simple,and reliable molecular measure for the identification of P.manihoti.This tool will be useful for quarantine,monitoring,and management of this invasive pest.
基金Supported by the National Natural Science Foundation of China(Nos.31572255,41522604,31301867)the Strategic Priority Research Program of CAS(No.XDA11020702)the Science and Technology Development Program of Yantai(No.2014ZH073)
文摘Peritrich ciliates are highly diverse and can be important bacterial grazers in aquatic ecosystems. Morphological identifi cations of peritrich species and assemblages in the environment are time-consuming and expertise-demanding. In this study, two peritrich-specifi c PCR primers were newly designed to amplify a fragment including the internal transcribed spacer(ITS) region of ribosomal rDNA from environmental samples. The primers showed high specifi city in silico, and in tests with peritrich isolates and environmental DNA. Application of these primers in clone library construction and sequencing yielded exclusively sequences of peritrichs for water and sediment samples. We also found the ITS1, ITS2, ITS, D1 region of 28 S rDNA, and ITS+D1 region co-varied with, and generally more variable than, the V9 region of 18 S rDNA in peritrichs. The newly designed specifi c primers thus provide additional tools to study the molecular diversity, community composition, and phylogeography of these ecologically important protists in dif ferent systems.
基金supported financially by the Frontier Science Projects Programme of the Institute of Hydrobiology,the Chinese Academy of Sciences(No.220207)
文摘In this paper, we took the lead in studying on specificity of the microsatellite DNA loci and applicability of mi crosatellite DNA primers in protozoa. In order to study characters of microsatellites in free living protozoa, eight microsatellite loci primers developed from Trypanosoma cruzi (MCLE01, SCLE10, MCLE08, SCLE11, MCLF10, MCLG10, MCL03, MCL05) were employed to amplify microsatellite in four free living protozoa, including Bodo designis, Euglena gracilis FACHB848, Paramecium bruzise and Tetrahymena thermophila BF1. In the amplification systems of P. bruzise, four loci (SCLE10, SCLE11, MCLF10, MCL03) were amplified successfully, and four amplification fragments were in proper size. In genome of E. gracilis FACHB848, five of eight primers brought five clear amplification bands. In B. designis, three (No.4, 5 and 7) of eight loci produced clear and sharp products without stutter bands, whereas no bands appeared in T. thermophila BF1. Further, eight 300-500 bp amplification fragments were cloned and sequenced. Nevertheless, all sequenced products did not contain corresponding microsatellite sequence, although Bodo is in the same order and has the nearest phylogenetic relation with Trypanosoma among these four species. Thus, the microsatellite DNA primers can not be applied among order or more far taxa, and the specificity of microsatellite DNA is very high in protozoa. The results of this study will contribute to our understanding of microsatellite DNA in protozoa.
文摘The possibility of identifying gunshot residue (GSR) particles produced by non-toxic primers containing only titanium and zinc is a very difficult task using SEM/EDX analysis employed in the analysis of GSR originating from primers containing lead, barium and antimony. However, Bauer et al. demonstrated that non-toxic (TieZn) primers form a TiZn2O4 spinel crystalline structure using SEM/EDX with EBSD (Electron Back Scatter Diffraction) and TKD (Transmission Kikuchi Diffraction), whereas GSR originating from gadolinium-doped TieZn primers form a non-crystalline glass phase. Here, a possible explanation of these different phenomena is hypothesized.
基金funded by a FPU a grant from the Ministry of Education of Spain
文摘Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biological samples.Methods:Strains were isolated,DNA extracted,and classified by using three Polymerase Chain Reactions(PCR).Subsequently this DNA was used along with other isolates of various biological samples,for a new PCR using primers designed.Finally,the amplified fragments were sequenced.Results:It was observed the predominance of DTU i in Colombia,as well as the specificity of our primers for detection of T.cruzi,while no band was obtained when other species were used.Conclusions:This work reveals the genetic variability of 21 new isolates of T.cruzi in Colombia.Our primers confirmed their specificity for detecting the presence of T.cruzi.
基金Supported by Suzhou Science and Technology Plan Projects"Monitoring and Early Warning and Prevention Technology for Alien Harmful Organism of Fall Webworm"(SYN201114)
文摘[ Objective ] The paper was to compare different extraction methods for genomie DNA of fall webworm [ Hyphantria cunea (Drury) ] and study the am- plification effect of different primers on sequences of CO I and CO II and Cytb. [Method] With winter pupae of fall webworm as the test materials, genomic DNA of fall webworm were extracted by five different methods including CTAB method, SDS method, improved SDS method, kit method and different processing time. Six groups of different primers were used to amplify sequences of CO I and CO II and Cytb. [ Result~ Full DNA could be extracted by CTAB method, SDS method and improved SDS method, and the effort of low concentration SDS method was the best. Six groups of primers could amplify the corresponding fragment, and two groups of primers had the best effort for amplification of CO I . [ Conclusion] The study provides better methods for DNA extraction.
基金supported by grants from the Significant Special Found of "13115" S&T Innovation Project of Shaanxi Province,China(2007 ZDKG-01)"13115" Technology Innovation Engineering and Engineering Technology Research Center of Shaanxi Province,China(2008 ZDGC-02)the Special Capital for the Construction of Modern Agriculture Technical System of Shaanxi Province,China (NYCYTX-001)
文摘In the present study, one unique low-molecular-weight glutenin subunit (LMW-GS) gene. LMWXY22-2 (GenBank no. FJ028810), was isolated from wheat cultivar Xiaoyan 22 (Triticum aestivum L.) by a pair of genomic specific PCR primers for 1B chromosome. Sequence analysis revealed that LMWXY22-2 was composed of 1 364 bp nucleotides, including a 317 bp promotion region and a 1 047 bp coding region which could be translated into a mature protein of 349 amino acids. In spite of a few minor mutations, the sequence of 5' untranslated region (UTR), the coding region, the deduced N- and Cterminus comparisons indicated that LMWXY22-2 belonged to the reported subunits of LMW-m type and type lII group 5, respectively. Inner gene markers for 1D chromosome together with the phylogenetic analysis revealed that this gene was classified into Glu-D3, which was not in agreement with the I B locus-specific primers for LMW genes completely.
基金Supported by Special Fund for the Screening and Breeding of Low-Cd-accumulating Crop Varieties~~
文摘Different results of seed purity identification for Gangyou 158, Ⅱ You 808, Wuyou 308 and Tianfengyou 316 were obtained using different SSR primers in our early work. To find out the reasons, the four hybrid combinations were grown in field to identify their purity according to their phenotypic traits. Then, the results of field identification were compared with that of laboratory tests using different SSR primers. The comparison revealed that only sterile lines (female parent) were distin- guished from true hybrids using the primers RM208, RM264, RM242 and RM164 for the purity identification of Gangyou 158, II You 808, Wuyou 308 and Tianfengyou 316, so the results were higher than that of field identification. In contrast, the primers RM341, RM297, RM21 and RM110 were able to distinguish not only the sterile plants but also the cross-pollinated ones from the true hybrids of Gangyou 158,Ⅱ You 808, Wuyou 308 and Tianfengyou 316, and the results of purity identifi- cation using them were close that of field identification, in summary, several pairs of primers should be used for the purity identification of rice hybrids to distinguish all the off-type plants and thus improve the accuracy.
基金Supported by Natural Science Foundation of Fujian Province (2011J01066, 2012JO1061)。
文摘[Objective]The paper was to establish a rapid identification method of Bactrocera cilifera(Hendel)with species-specific primers(SS-COI).[Method]Using B.cilifera(Hendel)as the positive control,and 19 species of fruit flies such as B.diaphora(Coquillett)and B.dorsalis(Hendel)as the negative controls,a pair of species-specific primers,YF290 and YR511,were designed and screened for accurate identification of B.cilifera,based on mitochondrial DNA COI sequence.[Result]The PCR products were amplified and detected by electrophoresis.Only a clear and single band was observed at about 222 bp in the positive control,while no bands were found in the other negative controls.[Conclusion]The established rapid identification method with species-specific primers(SS-COI)is of great practical significance for rapid identification of fruit flies intercepted from import and export fruits and vegetables at ports,and for rapid clearance and early warning of import fruits and vegetables at ports.
文摘The availability of the plastid genome sequences is one of the bases for comparative,functional,and structural genomic studies of plastid-containing living organisms,in addition to the application
文摘In an effort to simplify the procedure and to reduce the cost of fluorescence SSR analysis, the conditions of the multiplex PCR and the multiplex gel electrophoresis were optimized in the genetic analysis of sunflower (Helianthus annuus L.) inbred lines. Results indicated that factors for a successful multiplex PCR assay were related to the cycling touchdown annealing temperature, the balance of primer concentration at the various loci, the concentration of PCR buffer and the Taq DNA polymerase. Based on the optimization, a tailed primer strategy was outlined, and the effective ways were proposed to overcome the troubleshootings commonly encountered in the multiplex PCR and the multiplex gel electrophoresis.
基金Supported by(in part)Grants UH2CA140233 from the Human Microbiome Project of the NIH Roadmap Initiative and National Cancer InstituteR01AI063477 from the National Institute of Allergy and Infectious Diseases+1 种基金DE-11443 from the National Institute of Dental and Craniofacial ResearchU19DE018385 from the National Institute of Dental & Craniofacial Research
文摘AIM:To design and validate broad-range 16S rRNA primers for use in high throughput sequencing to classify bacteria isolated from the human foregut microbiome.METHODS:A foregut microbiome dataset was constructed using 16S rRNA gene sequences obtained from oral,esophageal,and gastric microbiomes produced by Sanger sequencing in previous studies represented by 219 bacterial species.Candidate primers evaluated were from the European rRNA database.To assess the effect of sequence length on accuracy of classification,16S rRNA genes of various lengths were created by trimming the full length sequences.Sequences spanning various hypervariable regions were selected to simulate the amplicons that would be obtained using possible primer pairs.The sequences were compared with full length 16S rRNA genes for accuracy in taxonomic classification using online software at the Ribosomal Database Project (RDP).The universality of the primer set was evaluated using the RDP 16S rRNA database which is comprised of 433 306 16S rRNA genes,represented by 36 phyla.RESULTS:Truncation to 100 nucleotides(nt)downstream from the position corresponding to base 28 in the Escherichia coli 16S rRNA gene caused misclassification of 87(39.7%)of the 219 sequences,compared with misclassification of only 29(13.2%)sequences with truncation to 350 nt.Among 350-nt sequence reads within various regions of the 16S rRNA gene,the reverse read of an amplicon generated using the 343F/798R primers had the least(8.2%)effect on classification.In comparison,truncation to 900 nt mimicking single pass Sanger reads misclassified 5.0%of the 219 sequences.The 343F/798R amplicon accurately assigned 91.8%of the 219 sequences at the species level.Weighted by abundance of the species in the esophageal dataset,the 343F/798R amplicon yielded similar classification accuracy without a significant loss in species coverage(92%).Modification of the 343F/798R primers to 347F/803R increased their universality among foregut species.Assuming that a typicalpolymerase chain reaction can tolerate 2 mismatches between a primer and a template,the modified 347F and 803R primers should be able to anneal 98%and 99.6%of all 16S rRNA genes in the RDP database.CONCLUSION:347F/803R is the most suitable pair of primers for classification of foregut 16S rRNA genes but also possess universality suitable for analyses of other complex microbiomes.