6Y1X

X-ray structure of the radical SAM protein NifB, a key nitrogenase maturating enzyme

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)	Radical SAM domain protein	polymer	309	35294.9	2	UniProt (A0B690) Pfam (PF04055)	Methanothrix thermoacetophila (strain DSM 6194 / JCM 14653 / NBRC 101360 / PT)
2	C, D, K, L (A, B)	IRON/SULFUR CLUSTER	non-polymer		351.6	4	Chemie (SF4)
3	E, F, H, I, J (A, B)	SULFATE ION	non-polymer		96.1	5	Chemie (SO4)
4	G, M (A, B)	CHLORIDE ION	non-polymer		35.5	2	Chemie (CL)
5	N, O (A, B)	water	water		18.0	397	Chemie (HOH)

Sequence modifications

A, B: 2 - 299 (UniProt: A0B690)

PDB	External Database	Details
Met -9	-	initiating methionine
Gly -8	-	expression tag
Ser -7	-	expression tag
His -6	-	expression tag
His -5	-	expression tag
His -4	-	expression tag
His -3	-	expression tag
His -2	-	expression tag
His -1	-	expression tag
Ala 0	-	expression tag
Ser 1	-	expression tag

Contents of the asymmetric unit

Polymers	Number of chains	2
	Total formula weight	70589.8
Non-Polymers*	Number of molecules	11
	Total formula weight	1957.8
All*	Total formula weight	72547.5

*Water molecules are not included.