# Enzyme Kinetics Fit (Lineweaver-Burk)

> Enzyme Kinetics Fit (Lineweaver-Burk) is a paid API for AI agents from www.mahastrategies.com, paid per call via x402, $0.169/call, status unknown (last checked 2026-10-17).

Fits substrate/velocity data pairs using reciprocal Lineweaver-Burk ordinary least squares regression to estimate Michaelis-Menten Km and Vmax kinetic parameters, with residuals reported.

## Facts

- Endpoint: POST https://www.mahastrategies.com/api/v1/micro/chemistry-enzyme-kinetics-fit?utm_source=zero.xyz
- Price: $0.169/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/enzyme-kinetics-fit-lineweaver-burk-5931c5e4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SdCJgbc66fJbq_w2w1xC0

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 enzyme-kinetics-fit-lineweaver-burk-5931c5e4 -d '<json body>'
```

Example prompt: I have enzyme kinetics data from my assay — substrate concentrations [0.5, 1.0, 2.0, 5.0, 10.0] and corresponding velocities [0.21, 0.35, 0.52, 0.71, 0.83] — can you fit a Lineweaver-Burk regression on this public dataset and tell me the Km, Vmax, and residuals?

## When to prefer this

Choose this endpoint when you need a quick, reproducible Lineweaver-Burk double-reciprocal OLS fit for enzyme kinetics data and do not require confidence intervals or bootstrap uncertainty estimates. Ideal for rapid parameter extraction from small-to-medium datasets (up to 128 points) in biochemistry workflows, simulation validation, or data preprocessing pipelines. Avoid if you need statistically robust parameter uncertainty quantification or nonlinear regression methods (e.g., direct Michaelis-Menten curve fitting).

## Known failure modes

- Mismatched array lengths for substrate and velocity (validation error)
- Arrays exceeding 128 items or containing fewer than 1 item (schema violation)
- Invalid dataClass value other than 'public' or 'synthetic'
- Poorly conditioned data (e.g., all-zero velocities) causing numerical instability
- Payment failure or insufficient USDC balance causing HTTP 402 rejection

## How this service works

Fit supplied substrate/rate pairs by reciprocal Lineweaver-Burk OLS; report Km, Vmax and residuals. Exposes noise bias; no parameter confidence interval.

## Output

Returns the estimated Michaelis constant (Km) and maximum reaction velocity (Vmax) derived from Lineweaver-Burk OLS regression, along with per-point residuals. Also includes offer metadata such as offerId, version, inputDigest, receiptDigest, amountBaseUnits, and any boundary records. Note: no parameter confidence intervals are reported, and the method exposes noise bias inherent to the double-reciprocal transform.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "dataClass",
      "substrate",
      "velocity"
     ],
     "properties": {
      "velocity": {
       "type": "array",
       "maxItems": 128,
       "minItems": 1
      },
      "dataClass": {
       "enum": [
        "public",
        "synthetic"
       ],
       "type": "string"
      },
      "substrate": {
       "type": "array",
       "maxItems": 128,
       "minItems": 1
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "version",
      "offerId",
      "amountBaseUnits",
      "inputDigest",
      "result",
      "boundaries",
      "receiptDigest"
     ],
     "properties": {
      "result": {
       "type": "object"
      },
      "offerId": {
       "enum": [
        "chemistry-enzyme-kinetics-fit"
       ],
       "type": "string"
      },
      "version": {
       "enum": [
        "maha-microproducts/0.1"
       ],
       "type": "string"
      },
      "boundaries": {
       "type": "array",
       "maxItems": 128,
       "minItems": 0
      },
      "inputDigest": {
       "type": "string",
       "maxLength": 71
      },
      "receiptDigest": {
       "type": "string",
       "maxLength": 71
      },
      "amountBaseUnits": {
       "enum": [
        "169000"
       ],
       "type": "string"
      }
     },
     "additionalProperties": false
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/enzyme-kinetics-fit-lineweaver-burk-5931c5e4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from www.mahastrategies.com](https://www.zero.xyz/host/www.mahastrategies.com/llms.txt)