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A J Bleasby

Publications and source records attributed to A J Bleasby.

14 recordsLinked to original sources

The Bioinformatics Template Library--generic components for biocomputing.

MOTIVATION: The efficiency of bioinformatics programmers can be greatly increased through the provision of ready-made software components that can be rapidly combined, with additional bespoke components where necessary, to create finished programs. The new standard for C++ includes an efficient and easy to use library of generic algorithms and data-structures, designed to facilitate low-level component programming. The extension of this library to include functionality that is specifically useful in compute-intensive tasks in bioinformatics and molecular modelling could provide an effective standard for the design of reusable software components within the biocomputing community. RESULTS: A novel application of generic programming techniques in the form of a library of C++ components called the Bioinformatics Template Library (BTL) is presented. This library will facilitate the rapid development of efficient programs by providing efficient code for many algorithms and data-structures that are commonly used in biocomputing, in a generic form that allows them to be flexibly combined with application specific object-oriented class libraries. AVAILABILITY: The BTL is available free of charge from our web site http://www.cryst.bbk.ac.uk/~classlib/ and the EMBL file server http://www.embl-ebi.ac.uk/FTP/index.html

Algorithms↗

Key residues approach to the definition of protein families and analysis of sparse family signatures.

We extend the concept of the motif as a tool for characterizing protein families and explore the feasibility of a sparse "motif" that is the length of the protein sequence itself. The type of motif discussed is a sparse family signature consisting of a set of N key residue positions (A1, A2...AN) preceded by gaps (G) thus G1A1G2A2. ...GNAN. Both a residue and gap can be variable. A signature is matched to a protein sequence and scored using a dynamic programming algorithm which permits variability in gap distance and residue type. Generating a signature involves identifying residues associated with points of contact in interactions between secondary structure elements. A raw signature consists of a set of positions with potential key structural roles sampled from a sequence alignment constructed with reference to this contact data. Raw signatures are refined by sampling different gap-residue pairs until the specificity of a signature for the family cannot be further improved. We summarize signatures for nine families of protein of diverse fold and function and present results of scans against the OWL protein sequence database. The implications of such signatures are discussed.

Algorithms↗

Information resources for the bioinformatician.

The collaborative computing project in biosequence and structure analysis (CCPII) was established to foster bioinformatics in the broad community and the UK research community in particular. A World-Wide Web site called 'The Bioinformatics Resource' has been created containing a comprehensive set of information resources of use to the bioinformatician. The activities of CCPII are complementary to other providers of molecular biology information such as the BIOSCI electronic communication forum, which was established to facilitate communication between professionals in the biological sciences.

Computational Biology↗

Novel developments with the PRINTS protein fingerprint database.

The PRINTS database of protein family 'fingerprints' is a diagnostic resource that complements the PROSITE dictionary of sites and patterns. Unlike regular expressions, fingerprints exploit groups of conserved motifs within sequence alignments to build characteristic signatures of family membership. Thus fingerprints inherently offer improved diagnostic reliability by virtue of the mutual context provided by motif neighbours. To date, 600 fingerprints have been constructed and stored in PRINTS, representing a 50% increase in the size of the database in the last year. The current version, 13.0, encodes approximately 3000 motifs, covering a range of globular and membrane proteins, modular polypeptides, and so on. The database is accessible via UCL's Bioinformatics World Wide Web (WWW) server at http://www.biochem.ucl.ac.uk/bsm/dbbrowser / . We describe here progress with the database, its Web interface, and a recent exciting development: the integration of a novel colour alignment editor (http://www.biochem.ucl.ac.uk/bsm/dbbrowser++ +/CINEMA ), which allows visualisation and interactive manipulation of PRINTS alignments over the Internet.

Amino Acid Sequence↗

Progress with the PRINTS protein fingerprint database.

PRINTS is a compendium of protein motif 'fingerprints' derived from the OWL composite sequence database. Fingerprints are groups of motifs within sequence alignments whose conserved nature allows them to be used as signatures of family membership. To date, 400 fingerprints have been constructed and stored in Prints, the size of which has doubled in the last year. The current version, 9.0, encodes approximately 2000 motifs, covering a range of globular and membrane proteins, modular polypeptides, and so on. Fingerprints inherently offer improved diagnostic reliability over single motif methods by virtue of the mutual context provided by motif neighbours. PRINTS thus provides a useful adjunct to the widely used PROSITE dictionary of patterns. The database is now accessible via the Database Browser on the UCL Bioinformatics server at http://www.biochem.ucl.ac.uk/bsm/dbbrowser .

Amino Acid Sequence↗

Singular over-representation of an octameric palindrome, HIP1, in DNA from many cyanobacteria.

An octameric palindrome (5'-GCGATCGC-3') is abundant in cyanobacterial sequences within databases (GenBank/EMBL) and was designated HIP1 (highly iterated palindrome). The frequency of occurrence of all 256 octameric palindromes has now been determined in sub-databases revealing large and unique over-representation of HIP1 in cyanobacterial entries. DNA sequences from other bacteria were searched for any over-represented octameric palindromes analogous to HIP1. Only two sequences were identified, in the genomes of a thermophile and halophilic archaebacteria, although these were less abundant than HIP1 in cyanobacteria and relate to codon usage. To test the proposed widespread distribution of HIP1 in DNA from the cyanobacterium Synechococcus PCC 6301, randomly selected genomic clones were partly sequenced. HIP1 constituted 2.5% of the novel sequences, equivalent to a site on average once every 320 nucleotides. An oligonucleotide including HIP1 was also tested in PCR. Multiple products were obtained using template DNA from cyanobacterial strains in which HIP1 is abundant in known sequences, and some strains generated characteristic HIP-PCR banding patterns. However, analysis of DNA from one strain (not previously represented in databases) by random sequencing, HIP-PCR and Pvul digestion, confirms that not all cyanobacterial genomes are rich in HIP1.

Base Sequence↗

OWL--a non-redundant composite protein sequence database.

A comprehensive, non-redundant composite protein sequence database is described. The database, OWL, is an amalgam of data from six publicly-available primary sources, and is generated using strict redundancy criteria. The database is updated monthly and its size has increased almost eight-fold in the last six years: the current version contains > 76,000 entries. For added flexibility, OWL is distributed with a tailor-made query language, together with a number of programs for database exploration, information retrieval and sequence analysis, which together form an integrated database and software resource for protein sequences.

Amino Acid Sequence↗

PRINTS--a database of protein motif fingerprints.

PRINTS is a compendium of protein motif 'fingerprints'. A fingerprint is defined as a group of motifs excised from conserved regions of a sequence alignment, whose diagnostic power or potency is refined by iterative databasescanning (in this case the OWL composite sequence database). Generally, the motifs do not overlap, but are separated along a sequence, though they may be contiguous in 3D-space. The use of groups of independent, linearly- or spatially-distinct motifs allows protein folds and functionalities to be characterised more flexibly and powerfully than conventional single-component patterns or regular expressions. The current version of the database contains 200 entries (encoding 950 motifs), covering a wide range of globular and membrane proteins, modular polypeptides, and so on. The growth of the databaseis influenced by a number of factors; e.g. the use of multiple motifs; the maximisation of sequence information through iterative database scanning; and the fact that the database searched is a large composite. The information contained within PRINTS is distinct from, but complementary to the consensus expressions stored in the widely-used PROSITE dictionary of patterns.

Amino Acid Sequence↗

CLUSTAL V: improved software for multiple sequence alignment.

The CLUSTAL package of multiple sequence alignment programs has been completely rewritten and many new features added. The new software is a single program called CLUSTAL V, which is written in C and can be used on any machine with a standard C compiler. The main new features are the ability to store and reuse old alignments and the ability to calculate phylogenetic trees after alignment. The program is simple to use, completely menu driven and on-line help is provided.

Phylogeny↗

Construction of validated, non-redundant composite protein sequence databases.

A strategy has been developed for the construction of a validated, comprehensive composite protein sequence database. Entries are amalgamated from primary source data bases by a largely automated set of processes in which redundant and trivially different entries are eliminated. A modular approach has been adopted to allow scientific judgement to be used at each stage of database processing and amalgamation. Source databases are assigned a priority depending on the quality of sequence validation and commenting. Rejection of entries from the lower priority database, in each pairwise comparison of databases, is carried out according to optionally defined redundancy criteria based on sequence segment mismatches. Efficient algorithms for this methodology are embodied in the COMPO software system. COMPO has been applied for over 2 years in construction and regular updating of the OWL composite protein sequence database from the source databases NBRF-PIR, SWISS-PROT, a GenBank translation retrieved from the feature tables, NBRF-NEW, NEWAT86, PSD-KYOTO and the sequences contained in the Brookhaven protein structure databank. OWL is part of the ISIS integrated data resource of protein sequence and structure [Akrigg et al. (1988) Nature, 335, 745-746]. The modular nature of the integration process greatly facilitates the frequent updating of OWL following releases of the source databases. The extent of redundancy in these sources is revealed by the comparison process. The advantages of a robust composite database for sequence similarity searching and information retrieval are discussed.

Amino Acid Sequence↗

Alpha 1-protease inhibitor in serous effusions: differences in lectin crossed immuno-affinoelectrophoresis precipitin profiles between benign and malignant disease.

Differences in the lectin crossed immuno-affinoelectrophoresis (LCIE) precipitin profile of the antiprotease alpha 1-protease inhibitor (alpha 1-PI) have been detected between serous effusions of benign and malignant origin. Extra proteins with antigenicity towards anti-human alpha 1-PI appear in both malignant pleural effusions and malignant ascitic fluid caused by ovarian cancer that are not detected in effusions of benign origin. These compounds may be protease-antiprotease complexes caused by tumour excretion of proteases into the serous effusions.

Ascitic Fluid↗

The PRINTS database of protein fingerprints: a novel information resource for computational molecular biology.

PRINTS is a compendium of protein motif fingerprints derived from the OWL composite sequence database. Fingerprints are groups of motifs within sequence alignments whose conserved nature allows them to be used as signatures of family membership. Fingerprints inherently offer improved diagnostic reliability over single motif methods by virtue of the mutual context provided by motif neighbors. To date, 650 fingerprints have been constructed and stored in PRINTS, the size of which has doubled in the last 2 years. The current version, 14.0, encodes 3500 motifs, covering a range of globular and membrane proteins, modular polypeptides, and so on. The database is now accessible via the UCL Bioinformatics Server on http:@ www.biochem.ucl.ac.uk/bsm/dbbrowser/. We describe here progress with the database, its compilation and interrogation software, and its Web interface.

Amino Acid Sequence↗