Distributed BLAST in a grid computing context

Abstract

The Basic Local Alignment Search Tool (BLAST) is one of the best known sequence comparison programs available in bioinformatics. It is used to compare query sequences to a set of target sequences, with the intention of finding similar sequences in the target set. Here, we present a distributed BLAST service which operates over a set of heterogeneous Grid resources and is made available through a Globus toolkit v.3 Grid service. This work has been carried out in the context of the BRIDGES project, a UK e-Science project aimed at providing a Grid based environment for biomedical research. Input consisting of multiple query sequences is partitioned into sub-jobs on the basis of the number of idle compute nodes available and then processed on these in batches. To achieve this, we have implemented our own Java-based scheduler which distributes sub-jobs across an array of resources utilizing a variety of local job scheduling systems