3CI7

Crystal structure of a simplified BPTI containing 20 alanines

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	bovine pancreatic trypsin inhibitor	polymer	58	5958.8	4			BPTI
2	A, B, D	SULFATE ION	non-polymer		96.1	4	Chemie (SO4)
3		water	water		18.0	277	Chemie (HOH)

Contents of the asymmetric unit

Polymers	Number of chains	4
	Total formula weight	23835.1
Non-Polymers*	Number of molecules	4
	Total formula weight	384.3
All*	Total formula weight	24219.3

*Water molecules are not included.