6S5C

Square conformation of KtrA WT ring with bound ATP and calcium

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)	Ktr system potassium uptake protein A	polymer	222	24916.8	2	UniProt (O32080) Pfam (PF02254) Pfam (PF02080)	Bacillus subtilis subsp. subtilis str. 168	K(+)-uptake protein KtrA,Regulatory protein of Ktr cation channel
2	C, E (A, B)	ADENOSINE-5'-TRIPHOSPHATE	non-polymer		507.2	2	Chemie (ATP)
3	D (A)	CALCIUM ION	non-polymer		40.1	1	Chemie (CA)

Contents of the asymmetric unit

Polymers	Number of chains	2
	Total formula weight	49833.5
Non-Polymers*	Number of molecules	3
	Total formula weight	1054.4
All*	Total formula weight	50888.0

*Water molecules are not included.