The National Center for Biotechnology Information maintains a database of protein sequences. The database is available online here through Entrez. The sequences are provided through a multitude of sources including other databases like UniProt (Universal Protein Resource) and the National Institutes of Health GenBank. Information about proteins from all organisms are available through a simple search tool. Each page includes the size of the protein, its gene locus, its amino acid sequence, the organism it comes from, and a reference to the original sequence. However, the database does NOT provide the nucleotide sequence, this information is available on the NCBI Nucleotide database (Romiti 2010).
The NCBI, a part of American National Library of Medicine, launched the Entrez website in 1994. Entrez provides users with a standard interface for searching a combination of international databases of many biomolecules. Entrez means "Come in!" in French (Wikipedia 2014).
Using the Protein Database Edit
Starting from the homepage, users can enter the name of the protein they are searching for along with a target organism or a specific article title or author. After clicking the search button, the user is taken to a page displaying all the relevant results, which can be further narrowed down using filters on the sides of the page. Clicking on a blue title will take the user to the page with that protein's information and amino acid sequence.
Monica Remeti (2010). Entrez Nucleotide and Entrez Protein FAQs.
Entrez (2014). Wikipedia.
Entrez Protein Database