The researches in molecular biology have been producing a large amount of data and they need to be well organized, structured and persisted. Mostly biological data are stored on files in text format. For large volumes of data, the natural way would be to use DBMS to manage them. However, these systems do not have adequate structures to represent and manipulate data specific to the domain. For example, biological sequences are typically treated as simple strings (type text/varchar) or BLOB, and thus lost a whole set of compositional, positional and content information. This thesis argues that the management of data (structure, storage and data access) has become a major problem for researches in bioinformatics. Thus we propose a conceptual model for representing biological information of the central dogma of molecular biology, as well as an Abstract Data Types (ADT) specific for the manipulation of biological sequences and its derivatives.