# UniProt Protein Sequence Lookup

> UniProt Protein Sequence Lookup is a paid API for AI agents from win.oneshotagent.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-29).

Retrieves the reference amino-acid sequence of a protein or isoform by UniProt accession, including sequence length, molecular weight, checksums, and isoform list.

## Facts

- Endpoint: POST https://win.oneshotagent.com/v1/tools/lookup/protein-sequence?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/uniprot-protein-sequence-lookup-d7a16d19
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__WGHGkE8HWI9rpcvMnMo-

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability uniprot-protein-sequence-lookup-d7a16d19 -d '<json body>'
```

Example prompt: Can you look up the reference amino acid sequence, length, and isoforms for the human TP53 protein using its UniProt accession P04637?

## When to prefer this

Choose this endpoint when you need structured protein sequence data — including isoforms, weight, and checksums — directly from UniProt without setting up your own UniProt API integration. Ideal for AI agents that need to programmatically retrieve protein metadata as part of a bioinformatics workflow, drug discovery pipeline, or sequence validation task, especially when pay-per-call pricing is preferable to managing API keys.

## Known failure modes

- Invalid or non-existent UniProt accession returns an error or empty result
- Malformed accession format (e.g. missing dash for isoform) causes a validation error
- Network or service timeout for large proteins
- Payment failure if x402 micropayment is not processed correctly

## How this service works

Get the reference amino-acid sequence of a protein or an isoform by UniProt accession, with its length, weight, checksums and isoforms.

## Output

Returns the full reference amino acid sequence for the requested protein or isoform, along with the sequence length, molecular weight, CRC64 and MD5 checksums, and a list of available isoforms associated with the UniProt accession.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "accession": {
   "type": "string",
   "description": "The UniProt accession, for example P04637, or an isoform accession, for example P04637-2"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "protein": null,
  "inactive": {
   "reason": "demerged",
   "replaced_by": [
    "P99999",
    "P99998"
   ]
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/uniprot-protein-sequence-lookup-d7a16d19/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from win.oneshotagent.com](https://www.zero.xyz/host/win.oneshotagent.com/llms.txt)