9RU4

Crystal structure of a sialic acid binding protein, Q216A mutant, from Streptococcus pneumoniae bound to Neu5Ac

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)	Sugar ABC transporter, sugar-binding protein	polymer	439	48254.9	2	UniProt (A0A0H2URD1) Pfam (PF01547)	Streptococcus pneumoniae TIGR4
2	C, E (A, B)	N-acetyl-alpha-neuraminic acid	non-polymer		309.3	2	Chemie (SIA) PubChem (444885)
3	D, F (A, B)	SULFATE ION	non-polymer		96.1	2	Chemie (SO4)
4	G, H (A, B)	water	water		18.0	1130	Chemie (HOH)

Sequence modifications

A, B: 23 - 442 (UniProt: A0A0H2URD1)

PDB	External Database	Details
Met 4	-	initiating methionine
Ala 5	-	expression tag
His 6	-	expression tag
His 7	-	expression tag
His 8	-	expression tag
His 9	-	expression tag
His 10	-	expression tag
His 11	-	expression tag
Ser 12	-	expression tag
Ser 13	-	expression tag
Gly 14	-	expression tag
Leu 15	-	expression tag
Glu 16	-	expression tag
Val 17	-	expression tag
Leu 18	-	expression tag
Phe 19	-	expression tag
Gln 20	-	expression tag
Gly 21	-	expression tag
Pro 22	-	expression tag
Ala 216	Gln 216	engineered mutation

Contents of the asymmetric unit

Polymers	Number of chains	2
	Total formula weight	96509.8
Non-Polymers*	Number of molecules	4
	Total formula weight	810.7
All*	Total formula weight	97320.5

*Water molecules are not included.