6J6J

Biotin-bound streptavidin

Entity

Entity ID	Chain ID	Description	Type	Chain length	Formula weight	Number of molecules	DB Name (Accession)	Biological source	Descriptive keywords
1	A, B, C, D	Streptavidin	polymer	119	12596.6	4	UniProt (P22629) Pfam (PF01382) In PDB	Streptomyces avidinii
2	A, B, C, D	BIOTIN	non-polymer		244.3	4	Chemie (BTN)
3		water	water		18.0	12	Chemie (HOH)

Contents of the asymmetric unit

Polymers	Number of chains	4
	Total formula weight	50386.6
Non-Polymers*	Number of molecules	4
	Total formula weight	977.2
All*	Total formula weight	51363.8

*Water molecules are not included.