Token	Definition	Example
_chem_comp.id	The alphanumeric code for the chemical component.	HYP
_chem_comp.name	The name of the chemical component.	4-HYDROXYPROLINE
_chem_comp.type	The type of monomer.	L-peptide linking
_chem_comp.pdbx_type	A preliminary internal classification used by PDB.	ATOMP
_chem_comp.formula	The chemical formula of the chemical component.	C5 H9 N1 O3'
_chem_comp.mon_nstd_parent_comp_id	The identifier for the parent component of the nonstandard component. May be a comma-separated list if this component is derived from multiple components.	PRO
_chem_comp.pdbx_synonyms	Synonym list for the non-standard residue.	HYDROXYPROLINE
_chem_comp.pdbx_formal_charge	The formal charge on the chemical component.	+1
_chem_comp.pdbx_initial_date	Date the chemical component was added to the database.	yyyy-mm-dd
_chem_comp.pdbx_modified_date	Date that the component was last modified.	yyyy-mm-dd
_chem_comp.pdbx_ambiguous_flag	For ligands with unconventional bonding (i.e. ligands with transition metal complexes).	code
_chem_comp.pdbx_release status	Status of ligand (released, hold, obsoleted).	yyyy-mm-dd
_chem_comp.pdbx_replaced_by	Identifies the _chem_comp.id of the new component that has replaced this component.	3-letter identifier
_chem_comp.pdbx_replaces	Identifies the _chem_comp.id of the component this entry replaces. Converse of _replaced_by.	3-letter identifier
_chem_comp.formula_weight	Formula mass of the chemical component in Daltons.	131.131
_chem_comp.one_letter_code	Reports the one-letter code of the component, if applicable.	one-letter identifier
_chem_comp.three_letter_code	Reports the three-letter code of the component, if applicable.	ATP
_chem_comp.pdbx_model_coordinates_details	Provides additional details about the model coordinates in the component definition.	text
_chem_comp.pdbx_model_coordinates_missing_flag	This data item identifies if model coordinates are missing in this definition	Y or N
_chem_comp.pdbx_ideal_coordinates_details	Identifies the source of the ideal coordinates in the component definition.	text
_chem_comp.pdbx_ideal_coordinates_missing_flag	Identifies if ideal coordinates are missing in this definition.	Y or N
_chem_comp.pdbx_model_coordinates_db_code	Identifies the PDB database code from which the heavy atom model coordinates were obtained.	PDB entry id
_chem_comp.pdbx_processing_site	Identifies the deposition site that processed this chemical component defintion.	RCSB PDB, PDBj, PDBe