Education
ε280 = 5500×Trp + 1490×Tyr + 125×cystine (Pace 1995, ±5%) from a sequence or residue counts, with reduced/oxidized brackets, ProtParam molecular weight, A0.1% = ε/MW, and c = A280/ε concentration conversion. Gill & von Hippel / Pace / ProtParam derived. Educational use only.
Call this tool from your code in three languages.
curl -X POST 'http://127.0.0.1:3003/en/api/tools/protein-extinction-coefficient' \
-H 'Content-Type: application/json' \
-d '{"mode":"sequence","sequence":"GIVEQCCTSICSLYQLENYCN","trpCount":1,"tyrCount":2,"cysCount":4,"cysState":"reduced","molecularWeightKDa":0,"decimalPlaces":2}'Send a POST request with your inputs as JSON. File parameters require a separate upload first.
POST http://127.0.0.1:3003/en/api/tools/protein-extinction-coefficient| Name | Type | Required | Description |
|---|---|---|---|
| mode | select | Yes | Count W/Y/C from a sequence, or enter residue counts directly. |
| sequence | textarea | Yes | One-letter codes, 20 standard residues (FASTA headers, whitespace, and '*' are stripped); sequence mode. |
| trpCount | number | Yes | Number of tryptophans (counts mode); each contributes 5500 M⁻¹cm⁻¹. |
| tyrCount | number | Yes | Number of tyrosines (counts mode); each contributes 1490 M⁻¹cm⁻¹. |
| cysCount | number |
Add this tool to your Model Context Protocol server so AI agents can list and call it.
Add this block to your MCP client configuration:
{
"mcpServers": {
"elysiatools-protein-extinction-coefficient": {
"name": "protein-extinction-coefficient",
"description": "ε280 = 5500×Trp + 1490×Tyr + 125×cystine (Pace 1995, ±5%) from a sequence or residue counts, with reduced/oxidized brackets, ProtParam molecular weight, A0.1% = ε/MW, and c = A280/ε concentration conversion. Gill & von Hippel / Pace / ProtParam derived. Educational use only.",
"baseUrl": "http://127.0.0.1:3003/mcp/sse?toolId=protein-extinction-coefficient",
"command": "",
"args": [],
"env": {},
"isActive": true,
"type": "sse"
}
}
}After connecting to the SSE endpoint, list the exposed tools:
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/list"
}Invoke the tool by its id, passing arguments built from its parameters:
{
"jsonrpc": "2.0",
"id": 2,
"method": "tools/call",
"params": {
"name": "protein-extinction-coefficient",
"arguments": {
"mode": "sequence",
"sequence": "GIVEQCCTSICSLYQLENYCN",
"trpCount": 1,
"tyrCount": 2,
"cysCount": 4,
"cysState": "reduced",
"molecularWeightKDa": 0,
"decimalPlaces": 2
}
}
}| Yes |
| Number of cysteines (counts mode); each disulfide pair contributes 125 M⁻¹cm⁻¹ when oxidized. |
| cysState | select | Yes | Reduced cysteines contribute nothing; oxidized pairs (cystines) add 125 each. |
| molecularWeightKDa | number | No | Protein molecular weight for the A0.1% conversion in counts mode; 0 skips it. |
| decimalPlaces | number | No | — |
JSON result
{
"key": {...},
"metadata": {
"key": "value"
},
"error": "Error message (optional)",
"message": "Notification message (optional)"
}Questions or issues? Contact [email protected]