
KEGG
The gold standard for biological pathway mapping and genomic functional annotation.

The gold-standard database of experimentally validated metabolic pathways and biochemical reactions.

MetaCyc is an extensively curated, non-redundant database of metabolic pathways derived from experimentally validated biochemical literature. As a flagship component of the BioCyc database collection, it provides a comprehensive reference for metabolic engineering, synthetic biology, and systems biology. Unlike purely automated databases, MetaCyc's value lies in its high-fidelity manual curation, encompassing over 3,000 pathways from nearly 3,500 different organisms. Its architecture is built upon the Pathway Tools software, which facilitates advanced computational analysis including metabolic reconstruction and gap-filling. In the 2026 market, MetaCyc positions itself as the essential ground-truth dataset for training Large Language Models (LLMs) and Graph Neural Networks (GNNs) in the pharmaceutical and agricultural sectors. It supports rigorous biochemical modeling through the inclusion of enzyme kinetics, regulatory data, and atom-mapping. For enterprise users, it serves as the backbone for proprietary Pathway-Genome Databases (PGDBs), allowing organizations to integrate their proprietary genomic data with a global reference of biochemical knowledge. Data integrity is maintained through strict evidence-code hierarchies, ensuring researchers can distinguish between computationally predicted and experimentally verified reactions.
MetaCyc is an extensively curated, non-redundant database of metabolic pathways derived from experimentally validated biochemical literature.
Explore all tools that specialize in genome annotation. This domain focus ensures MetaCyc delivers optimized results for this specific requirement.
Tracks the movement of every non-hydrogen atom from reactants to products across all reactions in the database.
Seamless integration with a desktop-grade bioinformatics suite for visualization and PGDB construction.
A structured ontology describing the quality and source of information for every reaction and pathway.
A spreadsheet-like interface within the browser for large-scale data manipulation and cross-database mapping.
Overlays experimental omics data onto metabolic maps to visualize flux changes.
Stores Km, Vmax, and Kcat values directly linked to specific enzyme-reaction pairs.
Tools to compare metabolic capabilities across thousands of species simultaneously.
Create a BioCyc user account to access the MetaCyc database.
Determine if you require the web-based interface or a local installation via Pathway Tools software.
For local installation, verify compatibility with Linux or macOS environments.
Request a license key from SRI International (Commercial or Academic).
Download the MetaCyc flat files or the BioPAX level 3 export for offline analysis.
Configure the Pathway Tools environment variables to point to the local database files.
Initialize the API connection using Python or Perl libraries if performing programmatic queries.
Load your target genome sequence in GenBank or FASTA format for metabolic reconstruction.
Run the Pathologic tool to map genomic data against the MetaCyc reference database.
Validate reconstructed pathways using the MetaCyc evidence codes.
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Verified feedback from other users.
"Highly regarded as the most accurate biochemical database, though some users find the desktop software interface dated."
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The gold standard for biological pathway mapping and genomic functional annotation.
WikiPathways is an open science platform for biological pathways contributed, updated, and used by the research community.

STRING is a database of known and predicted protein-protein interactions.

A fast spliced aligner for RNA-seq data.
Seurat is an R package designed for single-cell RNA-seq data analysis, exploration, and integration of diverse single-cell data types.

Scalable toolkit for analyzing single-cell gene expression data in Python.