PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Fingerprint identification”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources

Improving protein identification from peptide mass fingerprinting through a parameterized multi-level scoring algorithm and an optimized peak detection.

We have developed a new algorithm to identify proteins by means of peptide mass fingerprinting. Starting from the matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) spectra and environmental data such as species, isoelectric point and molecular weight, as well as chemical modifications or number of missed cleavages of a protein, the program performs a fully automated identification of the protein. The first step is a peak detection algorithm, which allows precise and fast determination of peptide masses, even if the peaks are of low intensity or they overlap. In the second step the masses and environmental data are used by the identification algorithm to search in protein sequence databases (SWISS-PROT and/or TrEMBL) for protein entries that match the input data. Consequently, a list of candidate proteins is selected from the database, and a score calculation provides a ranking according to the quality of the match. To define the most discriminating scoring calculation we analyzed the respective role of each parameter in two directions. The first one is based on filtering and exploratory effects, while the second direction focuses on the levels where the parameters intervene in the identification process. Thus, according to our analysis, all input parameters contribute to the score, however with different weights. Since it is difficult to estimate the weights in advance, they have been computed with a generic algorithm, using a training set of 91 protein spectra with their environmental data. We tested the resulting scoring calculation on a test set of ten proteins and compared the identification results with those of other peptide mass fingerprinting programs.

Algorithms↗

Application of amplified fragment length polymorphism fingerprinting for taxonomy and identification of the soft rot bacteria Erwinia carotovora and Erwinia chrysanthemi.

The soft rot bacteria Erwinia carotovora and Erwinia chrysanthemi are important pathogens of potato and other crops. However, the taxonomy of these pathogens, particularly at subspecies level, is unclear. An investigation using amplified fragment length polymorphism (AFLP) fingerprinting was undertaken to determine the taxonomic relationships within this group based on their genetic relatedness. Following cluster analysis on the similarity matrices derived from the AFLP gels, four clusters (clusters 1 to 4) resulted. Cluster 1 contained Erwinia carotovora subsp. carotovora (subclusters 1a and 1b) and Erwinia carotovora subsp. odorifera (subcluster 1c) strains, while cluster 2 contained Erwinia carotovora subsp. atroseptica (subcluster 2a) and Erwinia carotovora subsp. betavasculorum (subcluster 2b) strains. Clusters 3 and 4 contained Erwinia carotovora subsp. wasabiae and E. chrysanthemi strains, respectively. While E. carotovora subsp. carotovora and E. chrysanthemi showed a high level of molecular diversity (23 to 38% mean similarity), E. carotovora subsp. odorifera, E. carotovora subsp. betavasculorum, E. carotovora subsp. atroseptica, and E. carotovora subsp. wasabiae showed considerably less (56 to 76% mean similarity), which may reflect their limited geographical distributions and/or host ranges. The species- and subspecies-specific banding profiles generated from the AFLPs allowed rapid identification of unknown isolates and the potential for future development of diagnostics. AFLP fingerprinting was also found to be more differentiating than other techniques for typing the soft rot erwinias and was applicable to all strain types, including different serogroups.

Bacterial Typing Techniques↗

Protein analysis by mass spectrometry and sequence database searching: a proteomic approach to identify human lymphoblastoid cell line proteins.

Lymphoblastoid cell lines correspond to in vitro EBV-immortalized lymphocyte B-cells. These cells display a suitable model for experiments dealing with changes in protein expression occurring upon B-cell differentiation, after drug treatment, or after inhibition of some transcription factors. For all these reasons we have undertaken an effort aimed at developing a hematopoietic cell line protein two-dimensional electrophoresis (2-DE) database, containing B-lymphoblastoid 2-DE maps. In this work, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) peptide mass fingerprinting analysis was adopted for protein identification. The peptide mass fingerprinting identification and the sequence coverage obtained on colloidal Coomassie blue (CBB) stained gel was close to that obtained using zinc-imidazole staining. Everything considered, CBB being more comfortable for subsequent spot manipulations, CBB staining was chosen for identification of a larger number of polypeptides. The results suggest that reticulation of the gel can interfere preventing the uptake of the enzyme during the in-gel digestion step. Consequently, low molecular mass proteins appear more difficult to identify by mass fingerprinting. Finally, the information provided in this study allows the construction of a new annoted reference map of human lymphoblastoid cell proteins. Among the identified proteins 60% were not yet positioned on 2-DE maps in three of the most important well-documented databases. The annoted map will be accessible via Internet on the LBPP server at URL:http:// www-smbh.univ-paris13.fr/lbtp/index.htm.

Acrylic Resins↗

Cimicifuga species identification by high performance liquid chromatography-photodiode array/mass spectrometric/evaporative light scattering detection for quality control of black cohosh products.

Black cohosh has become one of the most important herbal products in the US dietary supplements market. It is manufactured from roots and rhizomes of Cimicifuga racemosa (Ranunculaceae). Botanical identification of the raw starting material is a key step in the quality control of black cohosh preparations. The present report summarizes a fingerprinting approach based on high performance liquid chromatography-photodiode array/mass spectrometric/evaporative light scattering detection (HPLC-PDA/MS/ELSD) that has been developed and validated using a total of 10 Cimicifuga species. These include three North American species, Cimicifuga racemosa, Cimicifuga americana, Cimicifuga rubifolia, and seven Asian species, Cimicifuga acerina, Cimicifuga biternat, Cimicifuga dahurica, Cimicifuga heracleifolia, Cimicifuga japonica, Cimicifuga foetida, and Cimicifuga simplex. The chemotaxonomic distinctiveness of the HPLC fingerprints allows identification of all 10 Cimicifuga species. The triterpene glycoside cimigenol-3-O-arabinoside (3), cimifugin (12), and cimifugin-3-O-glucoside (18) were determined to be suitable species-specific markers for the distinction of C. racemosa from the other Cimicifuga species. In addition to identification, the fingerprint method provided insight into chemical interconversion processes occurring between the diverse triterpene glycosides contained in black cohosh. The reported method has proven its usefulness in the botanical standardization and quality control of black cohosh products.

Chromatography, High Pressure Liquid↗

Paraffin-wax-coated plates as matrix-assisted laser desorption/ionization sample support for high-throughput identification of proteins by peptide mass fingerprinting.

We compared trysin-digested protein samples desalted by ZipTip(C18) reverse-phase microcolumns with on-plate washing of peptides deposited either on paraffin-coated plates (PCP), Teflon-based AnchorChip plates, or stainless steel plates, before analysis by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Trypsinized bovine serum albumin and ovalbumin and 16 protein spots extracted from silver-stained two-dimensional gels of murine C(2)C(12) myoblasts or human leukocytes, prepared by the above two methods, were subjected to MALDI on PCP, AnchorChip plates, or uncoated stainless steel plates. Although most peptide mass peaks were identical regardless of the method of desalting and concentrating of protein samples, samples washed and concentrated by the PCP-based method had peptide peaks that were not seen in the samples prepared using the ZipTip(C18) columns. The mass spectra of peptides desalted and washed on uncoated stainless steel MALDI plates were consistently inferior due to loss of peptides. Some peptides of large molecular masses were apparently lost from samples desalted by ZipTip(C18) microcolumns, thus diminishing the quality of the fingerprint needed for protein identification. We demonstrate that the method of washing of protein samples on paraffin-coated plates provides an easy, reproducible, inexpensive, and high-throughput alternative to ZipTip(C18)-based purification of protein prior to MALDI-TOF-MS analysis.

Animals↗

Arbitrarily primed polymerase chain reaction fingerprinting for the genotypic identification of mutans streptococci from humans.

Determining whether two strains of bacteria are unique, identical or clonally related depends upon comparisons of phenotypic and/or genotypic traits. Individual isolates can then be grouped according to differences or similarities among those traits. One method of genotyping strains of bacteria is commonly referred to as chromosomal DNA fingerprinting. Previously, we generated chromosomal DNA fingerprints of mutans streptococci to study the transmission of this organism within families. Here, we developed and evaluated an arbitrarily primed polymerase chain reaction (AP-PCR) method for the genotypic characterization of mutans streptococci. Results were compared to those derived from the more conventional chromosomal DNA fingerprinting method. First, we showed that randomly selected clinical isolates displayed a unique banding profile by both methods; the mean similarity indices between DNA fragment patterns were 0.69 for chromosomal DNA fingerprinting and 0.74 for AP-PCR. This indicated that AP-PCR demonstrated less diversity than chromosomal DNA fingerprinting. Subsequently, we tested the agreement between chromosomal DNA fingerprinting and AP-PCR in determining genotypic similarities among 21 mutans streptococci strains obtained from 10 mother-child pairs, and 5 mutans streptococci strains from 5 fathers. The Kappa value for agreement was 0.88. We conclude that AP-PCR, which generates patterns of 8 to 12 amplicons, is capable of distinguishing strains of mutans streptococci among non-related individuals. Moreover, AP-PCR can discern both homogeneity and heterogeneity of mutans streptococci genotypes among mother and child pairs. Overall, we found that AP-PCR gave results comparable to those of chromosomal DNA fingerprinting.

Chromosomes, Bacterial↗

Automating proteome analysis: improvements in throughput, quality and accuracy of protein identification by peptide mass fingerprinting.

The use of robots has major effects on maximizing the proteomic workflow required in an increasing number of high-throughput projects and on increasing the quality of the data. In peptide mass finger printing (PMF), automation of steps downstream of two-dimensional gel electrophoresis is essential. To achieve this goal, the workflow must be fluid. We have developed tools using macros written in Microsoft Excel and Word to complete the automation of our platform. Additionally, because sample preparation is crucial for identification of proteins by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry, we optimized a sandwich method usable by any robot for spotting digests on a MALDI target. This procedure enables further efficient automated washing steps directly on the MALDI target. The success rate of PMF identification was evaluated for the automated sandwich method, and for the dried-droplet method implemented on the robot as recommended by the manufacturer. Of the two methods, the sandwich method achieved the highest identification success rate and sequence coverage of proteins.

Colonic Neoplasms↗

Protein identification by peptide mass fingerprinting.

A mass spectrum of the peptide mixture resulting from the digestion of a protein by an enzyme can provide a fingerprint of great specificity--so specific, in fact, that it is often possible to identify the protein from this information alone, without ambiguity. The general approach is to take a small sample of the protein of interest and digest it with a proteolytic enzyme, such as trypsin. The resulting digest mixture is analyzed by mass spectrometry, the ionization techniques of choice being matrix-assisted laser desorption or electrospray ionization. The experimental mass values are then compared with a database of peptide mass values, calculated by applying the enzyme cleavage rules to the entries in one of the major collections of sequence data, such as SwissProt or PIR. By using an appropriate scoring algorithm, the closest match or matches can be identified. If the "unknown" protein was present in the sequence database, then the goal is to identify that precise entry. If the sequence database does not contain the unknown protein, then a successful search will identify those entries that exhibit the closest sequence homology, often equivalent proteins from related species. An inverted strategy, in which experimental peptide mass fingerprints are accumulated in a database, has significant potential for identifying coding regions within sequence data from genomic DNA and, in doing so, correlating the genes with their expressed proteins. This review aims to provide an overview of the technique, compare the different database matching algorithms which have been described in the literature, and discuss the practical and theoretical factors which influence identification accuracy.

Algorithms↗

[Identification on Herba Hedyotidis by HPLC fingerprint pattern method].

OBJECTIVE: To establish a new identification and analysis method of Herba Hedyotidis. METHOD: HPLC fingerprint pattern method. RESULT: Experiment and analysis were carried out on seven samples, the standard HPLC fingerprint pattern method and characterisitic diffraction peaks of Herba Hedyotidis were obtained. CONCLUSION: This method can be used for the identification of Herba Hedyotidis.

Chromatography, High Pressure Liquid↗

Protein identification by mass profile fingerprinting.

We have developed an algorithm for identifying proteins at the sub-microgram level without sequence determination by chemical degradation. The protein, usually isolated by one- or two-dimensional gel electrophoresis, is digested by enzymatic or chemical means and the masses of the resulting peptides are determined by mass spectrometry. The resulting mass profile, i.e., the list of the molecular masses of peptides produced by the digestion, serves as a fingerprint which uniquely defines a particular protein. This fingerprint may be used to search the database of known sequences to find proteins with a similar profile. If the protein is not yet sequenced the profile can serve as a unique marker. This provides a rapid and sensitive link between genomic sequences and 2D gel electrophoresis mapping of cellular proteins.

Algorithms↗

Identification of Src transformation fingerprint in human colon cancer.

We used a classical rodent model of transformation to understand the transcriptional processes, and hence the molecular and cellular events a given cell undergoes when progressing from a normal to a transformed phenotype. Src activation is evident in 80% of human colon cancer, yet the myriad of cellular processes effected at the level of gene expression has yet to be fully documented. We identified a Src 'transformation fingerprint' within the gene expression profiles of Src-transformed rat 3Y1 fibroblasts demonstrating a progression in transformation characteristics. To evaluate the role of this gene set in human cancer development and progression, we extracted the orthologous genes present on the Affymetrix Hu95A GeneChip (12k named genes) and compared expression profiles between the Src-induced rodent cell line model of transformation and staged colon tumors where Src is known to be activated. A similar gene expression pattern between the cell line model and staged colon tumors for components of the cell cycle, cytoskeletal associated proteins, transcription factors and lysosomal proteins suggests the need for co-regulation of several cellular processes in the progression of cancer. Genes not previously implicated in tumorigenesis were detected, as well as a set of 14 novel, highly conserved genes with here-to-fore unknown function. These studies define a set of transformation associated genes whose up-regulation has implications for understanding Src mediated transformation and strengthens the role of Src in the development and progression of human colon cancer. Supportive Supplemental Data can be viewed at http://pga.tigr.org/PGApubs.shtml.

Animals↗

Protein identification by peptide mass fingerprinting.

Peptide mass fingerprinting is an effective way of identifying, e.g., gel-separated proteins, by matching experimentally obtained peptide mass data against large databases. However, several factors are known to influence the quality of the resulting matches, such as proteins contaminating the sample in question, modifications altering the mass of the peptides, ionization efficiency of the individual peptides, and the degree of missed cleavage sites. Here, these factors are discussed and methods for elimination of contaminants from the dataset and prediction of various modifications are introduced. Useful tips on how to specify various search parameters and how to manually evaluate the search results are also given.

Databases, Protein↗

Novel procedure for the identification of proteins by mass fingerprinting combining two-dimensional electrophoresis with fluorescent SYPRO red staining.

The fluorescent sensitive SYPRO Red dye was successfully employed to stain proteins in two-dimensional gels for protein identification by peptide mass fingerprinting. Proteins which are not chemically modified during the SYPRO Red staining process are well digested enzymatically in the gel and hence the resulting peptides can be efficiently eluted and analysed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A SYPRO Red two-dimensional gel of a complex protein extract from Candida albicans was analysed by MALDI-TOF MS. The validity of SYPRO Red staining was demonstrated by identifying, via peptide mass fingerprinting, 10 different C. albicans proteins from a total of 31 selected protein spots. The peptide mass signal intensity, the number of matched peptides and the percentage of coverage of protein sequences from SYPRO Red-stained proteins were similar to or greater than those obtained in parallel with the modified silver protein gel staining. This work demonstrates that fluorescent SYPRO Red staining is compatible with the identification of proteins separated on polyacrylamide gel and that it can be used as an alternative to silver staining. As far as we know, this is the first report in which C. albicans proteins separated using 2-D gels have been identified by peptide mass fingerprinting. The improved technique described here should be very useful for carrying out proteomic studies.

Amino Acid Sequence↗

[Identification on genuine and pseudo shayuanzi collected from different place by HPLC fingerprint].

OBJECTIVE: To establish the identification method for genuine and pseudo Shayuanzi by HPLC fingerprint. METHOD: The flavone, a kind of active composition in genuine (Astragalus complanatus) and analysed species was analysed by RP-HPLC. RESULT: The fingerprints of genuine Shayuanzi collected from different places showed the similar characteristics, but they were different from those of pseudo species A. adsuragen and A. sinicus. CONCLUSION: The HPLC fingerprint can be an identifing method for Shayuanzi.

Astragalus Plant↗

Separation and identification of rat skeletal muscle proteins using two-dimensional gel electrophoresis and mass spectrometry.

Skeletal muscle plays a major role in whole body protein metabolism, and changes in the rates of synthesis and degradation of proteins are likely to lead to characteristic changes in the amounts of different proteins in muscle under various physiological and pathological conditions. This paper demonstrates the feasibility of a proteomic approach to analyzing the protein composition of skeletal muscle. We report here the initial establishment of two-dimensional gel electrophoresis (2-D PAGE) reference maps for mixed skeletal muscle taken from the abdominal wall of a normal adult rat. We used immobilized pH gradients of 3-10 (non-linear) and 4-7 (linear), and matrix assisted laser desorption/ionization--time of flight mass spectrometry for protein identification by peptide mass fingerprinting. More than 600 protein spots were detected on each gel, of which 100 were excised and characterized. In-gel digestion followed by peptide mass fingerprinting enabled tentative identification of 74 of these, which included a wide range of myofibrillary and sarcoplasmic proteins. This database should provide the nucleus of a valuable resource for investigation of the biochemical basis of skeletal muscle pathologies in general and such specific disorders as alcoholic myopathy and injury.

Animals↗