List of possible API to use...

Search google with API and EBI (european bioinformatics institute)

List of services
http://www.ebi.ac.uk/Tools/webservices/


Protein Data Bank
http://www.ebi.ac.uk/pdbe/pdbe-rest-api
PDBe’s REST API is a programmatic way to obtain information from the PDB and EMDB
3D biomacromolecular structures

Who else uses the REST API

The popular 3D viewer Jmol/JSmol has already integrated the REST API calls for quality and cross-references. Jalview, Coot and CCP4 developers have expressed interest.

Python example: https://github.com/PDBeurope/PDBe_Programming

Proteins API

https://www.ebi.ac.uk/proteins/api/doc/

https://academic.oup.com/nar/article-lookup/doi/10.1093/nar/gkx237

Ontology API

https://www.ebi.ac.uk/ols/docs/api

Don't forget:

Uniprot Web services R package:

http://bioconductor.org/packages/release/bioc/html/UniProt.ws.html