Advances in analytical techniques have drastically increased the amount of biological data available, which in turn has increased the difficulty and complexity of biological knowledge discovery. It is important to have mechanisms to take full advantage of the data not only for doing simple searches, but also for answering ad hoc and complex questions at the user's will by virtually connecting the heterogeneous data sources. In this paper we propose and formally define new operators that can be used for sequence comparison and alignment. Furthermore, cross-database operators can be developed based on work presented in this paper to dynamically link different types of databases. We believe this will liberate biological researchers from unproductive labor and allow them to focus on pattern seeking and interpretation of results.