There are a large number of publicly available molecular interaction databases. These can be classified into three main types, according to their data-acquisition policies 14.
Primary databases are those that collect experimental molecular interaction data exclusively from peer-reviewed scientific publications. IntAct 11, MINT 10 and MatrixDB 16 are examples of this type of database. They can be further classified by the level of detail that they use to represent the information and the depth of their curation policies.
Now, let's have a look at the different types of curation that primary databases use to register molecular interaction data.