| Allowed Value | Details | 
|---|---|
| CCD Core | The chemical component is defined in the core CCD maintained by the wwPDB | 
| CCD MA | The chemical component is defined in the ModelArchive extension of the CCD | 
| CCD local | The chemical component is defined locally within the mmCIF file instance | 
| Allowed Value | Details | 
|---|---|
| CCD Core | The chemical component is defined in the core CCD maintained by the wwPDB | 
| CCD MA | The chemical component is defined in the ModelArchive extension of the CCD | 
| CCD local | The chemical component is defined locally within the mmCIF file instance |