obsolete cofactor transmembrane transporter activity true vitamin or cofactor transporter activity GO:0051184 1. Making inferences in GO about compounds based on the cofactor role curated by ChEBI creates relationships that are not always true which violates ontological principles for GO; therefore we will cease making these inferences. 2. It is not meaningful to group transport processes that are not all chemically related by the fact that they may be used as a cofactor. OBSOLETE. Enables the transfer of a cofactor from one side of a membrane to the other. A cofactor is a substance that is required for the activity of an enzyme or other protein. cofactor transporter activity molecular_function