---
title: "Predict translation initiation rate (OSTIR)"
method: POST
path: "/rbs_predict"
tags: ["Analysis"]
---

# Predict translation initiation rate (OSTIR)

`POST /rbs_predict`

## Request

- Base URL: `https://seqbench.com/api/v1`
- URL: `https://seqbench.com/api/v1/rbs_predict`
- Auth: none required

Predict the translation initiation rate at each start codon in a bacterial mRNA using OSTIR, the open-source continuation of the Salis lab RBS Calculator, with ViennaRNA free energies. Returns the predicted rate plus the full thermodynamic breakdown (16S rRNA:mRNA hybridization, mRNA unfolding, spacing, standby site, start-codon binding) for every start codon found. Rates are on an arbitrary scale — compare them as ratios, not as absolute expression levels. Runs ViennaRNA on a shared service and is therefore rate limited (see 429/503).

## Request body

- object
  - `sequence` string, required: mRNA sequence, raw or FASTA — the 5' UTR plus at least the start of the CDS. DNA (T) and RNA (U) are both accepted and scored identically. A, C, G, T/U only. Max 10,000 nt.
  - `start` number: Optional 1-based position; only consider start codons beginning at or after it.
  - `end` number: Optional 1-based position; only consider start codons beginning at or before it.
  - `antiShineDalgarno` string: Optional anti-Shine-Dalgarno sequence (the 16S rRNA 3' end) to model a non-E. coli host. Omit to use OSTIR's own E. coli default.

## Response `200`

Tool ran successfully.

- SuccessResponse: Standard success envelope returned by every single-tool call.
  - `ok` unknown, required
  - `tool` string, required: The tool slug that ran.
  - `result` object, required: Tool-specific output object. Its shape depends on the tool — call `GET /{tool}` or see the docs for each tool's fields.
  - `gate` GateResult
    - `pass` boolean, required: True if and only if every hard check passed.
    - `checks` GateCheck[], required
      - `id` string, required
      - `label` string, required
      - `severity` 'hard' | 'soft', required
      - `pass` boolean, required
      - `message` string, required
      - `value` number
      - `threshold` string
    - `notChecked` string[], required: Honest list of what this gate does NOT verify.
  - `provenance` Provenance, required
    - `apiVersion` string, required
    - `tool` union, required: Tool slug, or an array of slugs (one per step) for a workflow.
      - string
      - string[]
    - `generatedAt` string, date-time, required: ISO 8601 timestamp of when the result was generated.

## Other responses

- `400`: Invalid argument or the tool could not run.
- `404`: Unknown tool.
- `429`: Rate limited (metered tools only). Body carries code `rate_limited` and retryable `true`; honor the Retry-After header.
- `503`: A metered tool is momentarily at capacity. The identical request should succeed after Retry-After; body carries code `upstream_unavailable`.

---

[API](https://skmtc.dev/seqbench/apis/seqbench-api.md) · [All operations](https://skmtc.dev/seqbench/apis/seqbench-api/llms.txt) · [OpenAPI document](https://skmtc.dev/seqbench/apis/seqbench-api/revisions/132575216865?raw)