The Proteins REST API provides access to key biological data from UniProt and data from Large Scale Studies (LSS) mapped to UniProt. The services provide sequence feature annotations from UniProtKB, variation data from UniProtKB and mapped from LSS (1000 Genomes, ExAC and COSMIC), proteomics data mapped from MS-proteomics repositories (PeptideAtlas, MaxQB and EPD), antigen sequences mapped from Human Protein Atlas (HPA), proteomes and taxonomy search and retrieval, and reference genome coordinate mappings.
How to cite us: The proteins API: accessing key integrated protein and genome information (doi:10.1093/nar/gkx237)
We don't limit user requests at the moment. If you plan to retrieve large amount of data, please see example 3 to use pagination to get your data: examples.