4BX5

cis-divalent streptavidin

Entity

Entity ID	Chain ID	Description	Type	Chain length	Formula weight	Number of molecules	DB Name (Accession)	Biological source	Descriptive keywords
1	A, C (A, C)	STREPTAVIDIN	polymer	138	14343.2	2	UniProt (P22629) Pfam (PF01382)	STREPTOMYCES AVIDINII
2	B, D (B, D)	STREPTAVIDIN	polymer	127	13281.3	2	UniProt (P22629) Pfam (PF01382)	STREPTOMYCES AVIDINII
3	E, F, H, I (A, C)	1,2-ETHANEDIOL	non-polymer		62.1	4	Chemie (EDO)
4	G, J (B, D)	TETRAETHYLENE GLYCOL	non-polymer		194.2	2	Chemie (PG4)
5	K, L, M, N (A, B, C, D)	water	water		18.0	517	Chemie (HOH)

Sequence modifications

A, C: 13 - 139 (UniProt: P22629)

PDB	External Database	Details
Ala 23	Asn 47	engineered mutation
Asp 27	Ser 51	engineered mutation
Ala 45	Ser 69	engineered mutation
-	Asn 73	deletion
Asp 48	-	insertion
Asp 48	-	insertion
Asp 48	-	insertion
Gly 48	-	insertion
Asp 48	-	insertion
Asp 48	-	insertion
Asp 48	-	insertion
Gly 48	-	insertion
Asp 48	-	insertion
Asp 48	-	insertion
Asp 48	-	insertion
Gly 49	-	insertion

Contents of the asymmetric unit

Polymers	Number of chains	4
	Total formula weight	55249.0
Non-Polymers*	Number of molecules	6
	Total formula weight	636.7
All*	Total formula weight	55885.7

*Water molecules are not included.