Biological databases are libraries of life sciences information, collected from scientific experiments, published literature, high throughput experiment technology, and computational analyses. They contain information from research areas including genomics, proteomics, metabolomics, microarray gene expression, and phylogenetics.  Information contained in biological databases includes gene function, structure, localization (both cellular and chromosomal), clinical effects of mutations as well as similarities of biological sequences and structures.
Relational database concepts of computer science and Information retrieval concepts of digital libraries are important for understanding biological databases. Biological database design, development, and long-term management is a core area of the discipline of Bioinformatics. . Data contents include gene sequences, textual descriptions, attributes and ontology classifications, citations, and tabular data. These are often described as semi-structured data, and can be represented as tables, key delimited records, and XML structures. Cross-references among databases are common, using database accession numbers.
The following link collections hold further links to database resources.
Primary Sequence Databases
Protein Sequence Databases
Protein Structure Databases
Metabolic Pathway Databases
Mathematical Model Databases
PCR / Real Time PCR Primer Databases
Wiki Style Databases
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Brief. Bioinformatics 5 (1): 4–5. PMID 15153301.
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