2FMX

An open conformation of switch I revealed by Sar1-GDP crystal structure at low Mg(2+)

Entity

Entity ID	Chain ID	Description	Type	Chain length	Formula weight	Number of molecules	DB Name (Accession)	Biological source	Descriptive keywords
1	A, B	GTP-binding protein SAR1b	polymer	195	22061.3	2	UniProt (Q9QVY3) Pfam (PF00025) In PDB	Cricetulus griseus (Chinese hamster)	Sar1, GTBPB
2	A, B	SULFATE ION	non-polymer		96.1	2	Chemie (SO4)
3	A, B	GUANOSINE-5'-DIPHOSPHATE	non-polymer		443.2	2	Chemie (GDP)
4	B	MAGNESIUM ION	non-polymer		24.3	1	Chemie (MG)
5		water	water		18.0	199	Chemie (HOH)

Sequence modifications

A, B: 10 - 198 (UniProt: Q9QVY3)

PDB	External Database	Details
His 4	-	expression tag
His 5	-	expression tag
His 6	-	expression tag
His 7	-	expression tag
His 8	-	expression tag
His 9	-	expression tag

Contents of the asymmetric unit

Polymers	Number of chains	2
	Total formula weight	44122.7
Non-Polymers*	Number of molecules	5
	Total formula weight	1102.8
All*	Total formula weight	45225.5

*Water molecules are not included.