| 
547
 | 
     1 # Built-in Models
 | 
| 
 | 
     2 
 | 
| 
 | 
     3 COBRAxy includes two pre-installed metabolic models for human metabolism analysis.
 | 
| 
 | 
     4 
 | 
| 
 | 
     5 ## ENGRO2 (Recommended)
 | 
| 
 | 
     6 
 | 
| 
550
 | 
     7 **Best for**: Core metabolic analysis
 | 
| 
547
 | 
     8 
 | 
| 
550
 | 
     9 - ~500 reactions, ~400 metabolites, ~500 genes
 | 
| 
 | 
    10 - Core metabolic model
 | 
| 
547
 | 
    11 
 | 
| 
 | 
    12 ## Recon (Comprehensive)
 | 
| 
 | 
    13 
 | 
| 
 | 
    14 **Best for**: Genome-wide studies
 | 
| 
 | 
    15 
 | 
| 
 | 
    16 - ~10,000 reactions, ~5,000 metabolites, ~2,000 genes
 | 
| 
550
 | 
    17 - Most complete human metabolic network, including all metabolic pathways
 | 
| 
547
 | 
    18 
 | 
| 
 | 
    19 ## Usage
 | 
| 
 | 
    20 
 | 
| 
 | 
    21 ```bash
 | 
| 
 | 
    22 # Specify model name in any COBRAxy tool
 | 
| 
 | 
    23 tool_name --model ENGRO2 [options]
 | 
| 
 | 
    24 ```
 | 
| 
 | 
    25 
 | 
| 
 | 
    26 ## Technical Notes
 | 
| 
 | 
    27 
 | 
| 
 | 
    28 **Gene IDs**: All models support HGNC ID (e.g., `HGNC:5`), HGNC Symbol (e.g., `ALDOA`), Ensembl, and Entrez formats.
 | 
| 
 | 
    29 
 | 
| 
 | 
    30 **GPR Rules**: Gene-Protein-Reaction associations use Boolean logic (`and`, `or`).
 | 
| 
 | 
    31 
 | 
| 
 | 
    32 **Custom Models**: Use [Import Metabolic Model](../tools/import-metabolic-model) to extract and [Export Metabolic Model](../tools/export-metabolic-model) to create custom models.
 | 
| 
 | 
    33 
 | 
| 
 | 
    34 ## See Also
 | 
| 
 | 
    35 
 | 
| 
 | 
    36 - [RAS Generator](../tools/ras-generator) - Uses model GPR rules
 | 
| 
 | 
    37 - [RAS to Bounds](../tools/ras-to-bounds) - Applies flux constraints to models
 | 
| 
 | 
    38 - [Flux Simulation](../tools/flux-simulation) - Samples model flux distributions
 | 
| 
 | 
    39 - [Import Metabolic Model](../tools/import-metabolic-model) - Extract model data
 | 
| 
 | 
    40 - [Export Metabolic Model](../tools/export-metabolic-model) - Create custom models
 |