4DFR

CRYSTAL STRUCTURES OF ESCHERICHIA COLI AND LACTOBACILLUS CASEI DIHYDROFOLATE REDUCTASE REFINED AT 1.7 ANGSTROMS RESOLUTION. I. GENERAL FEATURES AND BINDING OF METHOTREXATE

Replaces:  2DFR

Entity

Entity ID	Chain ID	Description	Type	Chain length	Formula weight	Number of molecules	DB Name (Accession)	Biological source	Descriptive keywords
1	A, B (A, B)	DIHYDROFOLATE REDUCTASE	polymer	159	18020.4	2	UniProt (P0ABQ4) Pfam (PF00186)	Escherichia coli
2	C, E (A, B)	CHLORIDE ION	non-polymer		35.5	2	Chemie (CL)
3	D, G (A, B)	METHOTREXATE	non-polymer		454.4	2	Chemie (MTX)
4	F (B)	CALCIUM ION	non-polymer		40.1	1	Chemie (CA)
5	H, I (A, B)	water	water		18.0	428	Chemie (HOH)

Sequence modifications

A, B: 1 - 159 (UniProt: P0ABQ4)

PDB	External Database	Details
Asp 37	Asn 37	conflict
Lys 154	Glu 154	conflict

Contents of the asymmetric unit

Polymers	Number of chains	2
	Total formula weight	36040.8
Non-Polymers*	Number of molecules	5
	Total formula weight	1019.9
All*	Total formula weight	37060.6

*Water molecules are not included.