4XK0

Crystal structure of a tetramolecular RNA G-quadruplex in potassium

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, C)	RNA (5'-(*UP*GP*GP*GP*GP*U)-3')	polymer	6	1948.2	2		synthetic construct
2	C, D, E, F, G... (A, C)	POTASSIUM ION	non-polymer		39.1	9	Chemie (K)
3	H, I, N (A, C)	BARIUM ION	non-polymer		137.3	3	Chemie (BA)
4	O, P (A, C)	water	water		18.0	61	Chemie (HOH)

Contents of the asymmetric unit

Polymers	Number of chains	2
	Total formula weight	3896.4
Non-Polymers*	Number of molecules	12
	Total formula weight	763.9
All*	Total formula weight	4660.3

*Water molecules are not included.