4ZK4

Crystal structure of a chimeric acetylcholine binding protein from Aplysia californica (Ac-AChBP) containing loop C from the human alpha 3 nicotinic acetylcholine receptor in complex with 7-(5-isopropoxy-pyridin-3-yl)-1-methyl-1,7-diaza-spiro[4.4]nonane

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, E (A, B, C, D, E)	soluble acetylcholine receptor, neuronal acetylcholine receptor subunit alpha-3 chimera	polymer	229	26200.2	5	UniProt (Q8WSF8) UniProt (P32297) Pfam (PF02931)	Aplysia californica (California sea hare)
2	F, O (A, E)	MAGNESIUM ION	non-polymer		24.3	2	Chemie (MG)
3	G, H, J, L, M (A, B, C, D)	SULFATE ION	non-polymer		96.1	5	Chemie (SO4)
4	I (A)	TETRAETHYLENE GLYCOL	non-polymer		194.2	1	Chemie (PG4)
5	K, N (C, E)	(5R)-1-methyl-7-[5-(propan-2-yloxy)pyridin-3-yl]-1,7-diazaspiro[4.4]nonane	non-polymer		275.4	2	Chemie (TII)
6	P, Q, R, S, T (A, B, C, D, E)	water	water		18.0	439	Chemie (HOH)

Sequence modifications

A, B, C, D, E: 1 - 181 (UniProt: Q8WSF8)

PDB	External Database	Details
Tyr -7	-	expression tag
Lys -6	-	expression tag
Asp -5	-	expression tag
Asp -4	-	expression tag
Asp -3	-	expression tag
Asp -2	-	expression tag
Lys -1	-	expression tag
Leu 0	-	expression tag
Trp 55	Tyr 72	engineered mutation

A, B, C, D, E: 182 - 197 (UniProt: P32297)
A, B, C, D, E: 198 - 219 (UniProt: Q8WSF8)

PDB	External Database	Details
Val 199	Asn 216	engineered mutation
Ser 220	-	expression tag
Arg 221	-	expression tag

Contents of the asymmetric unit

Polymers	Number of chains	5
	Total formula weight	131001.0
Non-Polymers*	Number of molecules	10
	Total formula weight	1273.9
All*	Total formula weight	132274.9

*Water molecules are not included.