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@@ -1728,6 +1728,7 @@ API | Description | Auth | HTTPS | CORS |
 | [OpenAlex](https://docs.openalex.org/) | Open catalog of scholarly works, authors, institutions, sources, and concepts | No | Yes | Yes |
 | [OrbitalWiki](https://orbitalwiki.com/developers) | Catalog of 16,000+ satellites merging CelesTrak, GCAT, Wikidata; free tier included | `apiKey` | Yes | Yes |
 | [Purple Air](https://www2.purpleair.com/) | Real Time Air Quality Monitoring | No | Yes | Unknown |
+| [RCSB PDB](https://data.rcsb.org/) | 3D structures of proteins and nucleic acids | No | Yes | Yes |
 | [Remote Calc](https://github.com/elizabethadegbaju/remotecalc) | Decodes base64 encoding and parses it to return a solution to the calculation in JSON | No | Yes | Yes |
 | [Semantic Scholar](https://api.semanticscholar.org/) | Academic search engine for papers, authors, and citations | No | Yes | Unknown |
 | [SHARE](https://share.osf.io/api/v2/) | A free, open, dataset about research and scholarly activities | No | Yes | No |