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Biomedical subjects

D Westhead

Publications and source records attributed to D Westhead.

3 recordsLinked to original sources

A computer system to perform structure comparison using TOPS representations of protein structure.

We describe the design and implementation of a fast topology-based method for protein structure comparison. The approach uses the TOPS topological representation of protein structure, aligning two structures using a common discovered pattern and generating measure of distance derived from an insert score. Heavy use is made of a constraint-based pattern-matching algorithm for TOPS diagrams that we have designed and described elsewhere (Bioinformatics 15(4) (1999) 317). The comparison system is maintained at the European Bioinformatics Institute and is available over the Web at tops.ebi.ac.uk/tops. Users submit a structure description in Protein Data Bank (PDB) format and can compare it with structures in the entire PDB or a representative subset of protein domains, receiving the results by email.

Algorithms↗

Motif-based searching in TOPS protein topology databases.

MOTIVATION: TOPS cartoons are a schematic ion of protein three-dimensional structures in two dimensions, and are used for understanding and manual comparison of protein folds. Recently, an algorithm that produces the cartoons automatically from protein structures has been devised and cartoons have been generated to represent all the structures in the structural databank. There is now a need to be able to define target topological patterns and to search the database for matching domains. RESULTS: We have devised a formal language for describing TOPS diagrams and patterns, and have designed an efficient algorithm to match a pattern to a set of diagrams. A pattern-matching system has been implemented, and tested on a database derived from all the current entries in the Protein Data Bank (15,000 domains). Users can search on patterns selected from a library of motifs or, alternatively, they can define their own search patterns. AVAILABILITY: The system is accessible over the Web at http://tops.ebi.ac.uk/tops

Algorithms↗

Determination of plasma tranexamic acid using cation-exchange high-performance liquid chromatography with fluorescence detection.

A procedure is described for the determination of plasma tranexamic acid concentrations using cation exchange high-performance liquid chromatography with fluorescence detection following post-column derivatisation with omicron-phthalaldehyde. The chromatographic conditions were optimised with respect to detector performance and the method applied to measuring the plasma tranexamic acid levels of patients in a double-blind trial.

Chromatography, High Pressure Liquid↗