ExPASy: The proteomics server for in-depth protein knowledge and analysis

The ExPASy (the Expert Protein Analysis System) World Wide Web server (http://www.expasy.org), is provided as a service to the life science community by a multidisciplinary team at the Swiss Institute of Bioinformatics (SIB). It provides access to a variety of databases and analytical tools dedicated to proteins and proteomics. ExPASy databases include SWISS-PROT and TrEMBL, SWISS-2DPAGE, PROSITE, ENZYME and the SWISS-MODEL repository. Analysis tools are available for specific tasks relevant to proteomics, similarity searches, pattern and profile searches, post-translational modification prediction, topology prediction, primary, secondary and tertiary structure analysis and sequence alignment. These databases and tools are tightly interlinked: a special emphasis is placed on integration of database entries with related resources developed at the SIB and elsewhere, and the proteomics tools have been designed to read the annotations in SWISS-PROT in order to enhance their predictions. ExPASy started to operate in 1993, as the first WWW server in the field of life sciences. In addition to the main site in Switzerland, seven mirror sites in different continents currently serve the user community.     

The 1999 SWISS-2DPAGE database update

SWISS-2DPAGE (http://www.expasy.ch/ch2d/ ) is an annotated two-dimensional polyacrylamide gel electro-phoresis (2-DE) database established in 1993. The current release contains 24 reference maps from human and mouse biological samples, as well as from Saccharomyces cerevisiae, Escherichia coli and Dictyostelium discoideum origin. These reference maps have now 2824 identified spots, corresponding to 614 separate protein entries in the database, in addition to virtual entries for each SWISS-PROT sequence or any user-entered amino acids sequence. Last year improvements in the SWISS-2DPAGE database are as follows: three new maps have been created and several others have been updated; cross-references to newly built federated 2-DE databases have been added; new functions to access the data have been provided through the ExPASy proteomics server.     

The SWISS-2DPAGE database: what has changed during the last year.

SWISS-2DPAGE (http://www.expasy.ch/ch2d/) is an annotated two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) database established in 1993. The current release contains 21 reference maps from human and mouse biological samples, as well as from Saccharomyces cerevisiae, Escherichia coli and Dictyostelium discoideum origin. These reference maps now have 2480 identified spots, corresponding to 528 separate protein entries in the database, in addition to virtual entries for each SWISS-PROT sequence. During the last year, the SWISS-2DPAGE has undergone major changes. Six new maps have been added, and new functions to access the data have been provided through the ExPASy server. Finally, an important change concerns the database funding source.     

SWISS-2DPAGE, ten years later

The SWISS-2DPAGE database was established in 1993 and is maintained collaboratively by the Swiss Institute of Bioinformatics (SIB) and the Biomedical Proteomics Research Group (BPRG) of the Geneva University Hospital. During these years, SWISS-2DPAGE underwent constant modification and improvement. Current content includes about 4000 identified spots corresponding to 1200 different protein entries in 36 reference maps from human, mouse, Arabidopsis thaliana, Dictyostelium discoideum, Escherichia coli, Saccharomyces cerevisiae and Staphylococcus aureus origins. With a high level of annotation and integration with other relevant databases, SWISS-2DPAGE is a reference source in the proteomics world. Queries to SWISS-2DPAGE database currently reach 1000 hits per day.     

Web resources for the carbohydrate chemist

Bioinformatics has played a pivotal role in advancing genetics and protein sciences. The large amount of information generated by genomics, and now proteomics, has been a driving force. By comparison, glycobiology still generates small amounts of data. The need to organize our knowledge about carbohydrates is however growing constantly and has given rise to an increasing number of public databases and freely available tools. This review gives an overview of the carbohydrate-oriented resources currently available on the Internet. Many of the resources are seldom referred to in the literature and difficult to find, in part because of the constant flux of the net itself, but also because many efforts have been lead by a single individual. As the World Wide Web has matured the number of 'permanent' resources, maintained by organizations rather than individuals, has increased. In this paper, we present some of the more useful and accessible public tools and databases. There are also a few commercial initiatives but these have not been reviewed.     

A 2-D gel reference map of the basic human heart proteome

We have undertaken the identification of basic proteins (pH 6–11) of the human heart using 2‐DE. Tissue from the left ventricle of human heart was lysed and proteins were separated in the first dimension on pH 6–11 IPG strips using paper‐bridge loading followed by separation on 12% SDS polyacrylamide gels in the second dimension. Proteins were then identified by mass spectrometry and analysed using Proline, a proteomic data analysis platform that was developed in‐house. The proteome map contains 176 identified spots with 151 unique proteins and has been made available as part of the UCD‐2DPAGE database at http://proteomics‐portal.ucd.ie:8082 . The associated mass spectrometry data have been submitted to PRIDE (Accession number ?10098). This reference map, and the other heart reference maps available through the UCD‐2DPAGE database, will aid further proteomic studies of heart diseases such as dilated cardiomyopathy and ischaemic heart disease.     

Cancer and the web

The applications of functional genomics, proteomics and informatics to cancer research have yielded a tremendous amount of information, which is growing all the time. Much of this information is available publicly on the Internet and ranges from general information about different cancers from a patient or clinical viewpoint, through to databases suitable for cancer researchers of all backgrounds, to very specific sites dedicated to individual genes or molecules. A simple search for 'cancer' from a typical Web browser search engine yields more than half a million hits; an even more specific search for 'leukaemia' (>40 000 hits) or 'p53' (>5700 hits) yields far too many hits to allow one to identify particular sites of interest. This review aims to provide a brief guide to some of the resources and databases that can be used as springboards to home in rapidly on information relevant to many fields of cancer research. As such, this article will not focus on a single website but hopes to illustrate some of the ways that postgenomic biology is revolutionizing cancer research. It will cover genomics and proteomics approaches that have been applied to studying global expression patterns in cancers, in addition to providing links ranging from general information about cancer to specific cancer gene mutation databases.     

The ENZYME data bank in 1999.

The ENZYME data bank is a repository of information related to the nomenclature of enzymes. In recent years it has become an indispensable resource for the development of metabolic databases. The current version contains information on 3704 enzymes. It is available through the ExPASy WWW server (http://www.expasy.ch/).     

Proteome analysis of the plant-pathogenic bacterium Xanthomonas oryzae pv. oryzae

The plant-pathogenic bacterium Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of bacterial blight, which is one of the most serious diseases of rice. Xoo has been studied for over one century, and much has been learned about it, but proteomic investigation has been neglected. In this study, proteome reference maps of Xoo were constructed by two-dimensional gel electrophoresis, and 628 spots in the gels representing 469 different protein species were identified with MALDI-TOF/TOF MS. The identified spots were assigned to 15 functional categories according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database and the annotations from the National Center for Biotechnology Information (NCBI) database. The data set has been deposited in the World-2DPAGE database (Database ID: 0044). In addition, comparative proteomic analysis revealed that proteins related to the TonB-dependent transportation system and energy metabolism are involved in the phenazine-1-carboxylic acid resistance in Xoo. In conclusion, we have established a proteome database for Xoo and have used this database in a comparative proteomic analysis that identified proteins potentially contributing to phenazine-1-carboxylic acid resistance in Xoo.     

EcoProDB: the Escherichia coli protein database

EcoProDB is a web-based database for comparative proteomics of Escherichia coli. The database contains information on E. coli proteins identified on 2D gels along with other resources collected from various databases and published literature, with a special feature of showing the expression levels of E. coli proteins under different genetic and environmental conditions. It also provides comparative information of subcellular localization, theoretical 2D map, experimental 2D map and integrated protein information via an interactive web interface and application such as the Map Browser. Users can also upload their own 2D gels, extract core information associated with the proteins and 2D gel results from different experiments and consequently generate new knowledge and hypotheses for further studies. Availability: EcoProDB database system is accessible at http://eecoli.kaist.ac.kr.     

A Bioinformatics Perspective on Proteomics: Data Storage, Analysis, and Integration

The field of proteomics is advancing rapidly as a result of powerful new technologies and proteomics experiments yield a vast and increasing amount of information. Data regarding protein occurrence, abundance, identity, sequence, structure, properties, and interactions need to be stored. Currently, a common standard has not yet been established and open access to results is needed for further development of robust analysis algorithms. Databases for proteomics will evolve from pure storage into knowledge resources, providing a repository for information (meta-data) which is mainly not stored in simple flat files. This review will shed light on recent steps towards the generation of a common standard in proteomics data storage and integration, but is not meant to be a comprehensive overview of all available databases and tools in the proteomics community.     

FisOmics: A portal of fish genomic resources

An online portal, accessible at URL: http://mail.nbfgr.res.in/FisOmics/, was developed that features different genomic databases and tools. The portal, named as FisOmics, acts as a platform for sharing fish genomic sequences and related information in addition to facilitating the access of high-performance computational resources for genome and proteome data analyses. It provides the ability for quarrying, analysing and visualizing genomic sequences and related information. The featured databases in FisOmics are in the World Wide Web domain already. The aim to develop portal was to provide a nodal point to access the featured databases and work conveniently. Presently, FisOmics includes databases on barcode sequences, microsatellite markers, mitogenome sequences, hypoxia-responsive genes and karyology of fishes. Besides, it has a link to other molecular resources and reports on the on-going activities and research achievements.     

Arabidopsis thaliana proteomics: from proteome to genome

Proteomics has become an important approach for investigating cellular processes and network functions. Significant improvements have been made during the last few years in technologies for high-throughput proteomics, both at the level of data analysis software and mass spectrometry hardware. As proteomics technologies advance and become more widely accessible, efforts of cataloguing and quantifying full proteomes are underway to complement other genomics approaches, such as RNA and metabolite profiling. Of particular interest is the application of proteome data to improve genome annotation and to include information on post-translational protein modifications with the annotation of the corresponding gene. This type of analysis requires a paradigm shift because amino acid sequences must be assigned to peptides without relying on existing protein databases. In this review, advances and current limitations of full proteome analysis are briefly highlighted using the model plant Arabidopsis thaliana as an example. Strategies to identify peptides are also discussed on the basis of MS/MS data in a protein database-independent approach.     

Two‐dimensional reference map for the basic proteome of the human dorsolateral prefrontal cortex (dlPFC) of the prefrontal lobe region of the brain

We describe a 2‐DE proteomic reference map containing 227 basic proteins in the dorsolateral prefrontal cortex region of the human brain. Proteins were separated in the first dimension on pH 6–11 IPG strips using paper‐bridge loading and on 12% SDS‐PAGE in the second dimension. Proteins were subsequently identified by MS and spectra were analyzed using an in‐house proteomics data analysis platform, Proline. The 2‐DE reference map is available via the UCD 2‐DE Proteome Database ( http://proteomics‐portal.ucd.ie:8082 ) and can also be accessed via the WORLD‐2DPAGE Portal ( http://www.expasy.ch/world‐2dpage/ ). The associated protein identification data have been submitted to the PRIDE database (accession numbers 10018–10033). Separation of proteins in the basic region resolves more membrane associated proteins relevant to the synaptic pathology central to many neurological disorders. The 2‐DE reference map will aid with further characterisation of neurological disorders such as bipolar and schizophrenia.     

The ENZYME database in 2000

The ENZYME database is a repository of information related to the nomenclature of enzymes. In recent years it has became an indispensable resource for the development of metabolic databases. The current version contains information on 3705 enzymes. It is available through the ExPASy WWW server (http://www.expasy.ch/enzyme/ ).     

Entamoeba histolytica: construction and applications of subgenomic databases

Knowledge about the influence of environmental stress such as the action of chemotherapeutic agents on gene expression in Entamoeba histolytica is limited. We plan to use oligonucleotide microarray hybridization to approach these questions. As the basis for our array, sequence data from the genome project carried out by the Institute for Genomic Research (TIGR) and the Sanger Institute were used to annotate parts of the parasite genome. Three subgenomic databases containing enzymes, cytoskeleton genes, and stress genes were compiled with the help of the ExPASy proteomics website and the BLAST servers at the two genome project sites. The known sequences from reference species, mostly human and Escherichia coli, were searched against TIGR and Sanger E. histolytica sequence contigs and the homologs were copied into a Microsoft Access database. In a similar way, two additional databases of cytoskeletal genes and stress genes were generated. Metabolic pathways could be assembled from our enzyme database, but sometimes they were incomplete as is the case for the sterol biosynthesis pathway. The raw databases contained a significant number of duplicate entries which were merged to obtain curated non-redundant databases. This procedure revealed that some E. histolytica genes may have several putative functions. Representative examples such as the case of the delta-aminolevulinate synthase/serine palmitoyltransferase are discussed.     

Consequences of the discontinuation of the International Protein Index (IPI) database and its substitution by the UniProtKB "complete proteome" sets

The International Protein Index (IPI) database has been one of the most widely used protein databases in MS proteomics approaches. Recently, the closure of IPI in September 2011 was announced. Its recommended replacement is the new UniProt Knowledgebase (UniProtKB) "complete proteome" sets, launched in May 2011. Here, we analyze the consequences of IPI's discontinuation for human and mouse data, and the effect of its substitution with UniProtKB on two levels: (i) data already produced and (ii) newly performed experiments. To estimate the effect on existing data, we investigated how well IPI identifiers map to UniProtKB accessions. We found that 21% of human and 10% of mouse identifiers do not map to UniProtKB and would thus be "lost." To investigate the impact on new experiments, we compared the theoretical search space (i.e. the tryptic peptides) of both resources and found that it is decreased by 14.0% for human and 8.9% for mouse data through IPI's closure. An analysis on the experimental evidence for these "lost" peptides showed that the vast majority has not been identified in experiments available in the major proteomics repositories. It thus seems likely that the search space provided by UniProtKB is of higher quality than the one currently provided by IPI.     

糖类的生物信息学资源

生物信息学在推动遗传学和蛋白质科学的研究领域中,已发挥了举足轻重的作用.相比较而 言,糖科学产生的信息还比较有限,随着人们对糖类分子的关注,糖生物学的发展也出现新 的契机,其信息正在飞速地增长.对已经获得的糖类相关知识进行系统整合就显得越来越有 必要,许多研究型数据库和免费工具已应运而生,并且数目在不断扩大,正成为科学工作者 非常便利的工具.但到目前为止,许多数据库或者网络预测工具在文献中很少提及或难以找 到,给研究者带来了不少的麻烦.部分原因是数据库资源本身数据不断在更新,人机界面也 变得越方便和人性化,另外就是人们对于这些新型的研究工具了解较少.这篇综述介绍了 目前网络上最常用的糖类生物信息学资源,包括糖的一级结构,分析测试数据、构象,酶, 凝集素,糖蛋白等方面的各种数据库.     

A comparative view at comprehensive information resources on three-dimensional structures of biological macro-molecules.

The rapidly increasing amount of information on three-dimensional (3D) structures of biological macro-molecules has still an insufficient impact on genome analysis, functional genomics and proteomics as well as on many other fields in biomedicine including disease-related research. There are, however, attempts to make structural data more easily accessible to the bench biologist. As members of the world-wide Protein Data Bank (wwPDB), the RCSB Protein Data Bank (PDB), the Protein Data Bank Japan and the Macromolecular Structure Database are the primary information resources for 3D structures of proteins, nucleic acids, carbohydrates and complexes thereof. In addition, a number of secondary resources have been set up that also provide information on all currently known structures in a relatively comprehensive manner and not focusing on specific features only. They include PDBsum, the OCA browser-database for protein structure/function, the Molecular Modeling Database and the Jena Library of Biological Macromolecules--JenaLib. Both the primary and secondary resources often merge the information in the PDB files with data from other resources and offer additional analysis tools thereby adding value to the original PDB data. Here, we briefly describe these resources from a user's point of view and from a comparative perspective. It is our aim to guide researchers outside the structure biology field in getting the most out of the 3D structure resources.