2G9H

Crystal Structure of Staphylococcal Enterotoxin I (SEI) in Complex with a Human MHC class II Molecule

Entity

Entity ID	Chain ID	Description	Type	Chain length	Formula weight	Number of molecules	DB Name (Accession)	Biological source	Descriptive keywords
1	A	HLA class II histocompatibility antigen, DR alpha chain	polymer	182	21155.9	1	UniProt (P01903) Pfam (PF00993) Pfam (PF07654) In PDB	Homo sapiens (human)	MHC class II antigen DRA
2	B	HLA class II histocompatibility antigen, DRB1-1 beta chain	polymer	190	22080.7	1	UniProt (P04229) Pfam (PF00969) Pfam (PF07654) UniProt (by SIFTS) (P01911) In PDB	Homo sapiens (human)	MHC class I antigen DRB1*1, DR-1, DR1
3	C	Hemagglutinin	polymer	13	1506.8	1	UniProt (P04664) In PDB
4	D	extracellular enterotoxin type I	polymer	218	24962.0	1	UniProt (O85383) Pfam (PF01123) Pfam (PF02876) UniProt (by SIFTS) (Q52T95) In PDB	Staphylococcus aureus
5	A, C, D	SULFATE ION	non-polymer		96.1	4	Chemie (SO4)
6	A	4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID	non-polymer		238.3	1	Chemie (EPE)
7	A	1,4-DIETHYLENE DIOXIDE	non-polymer		88.1	2	Chemie (DIO)
8	D	ZINC ION	non-polymer		65.4	1	Chemie (ZN)
9		water	water		18.0	460	Chemie (HOH)

Sequence modifications

D: 1 - 218 (UniProt: O85383)

PDB	External Database	Details
Leu 24	Val 48	SEE REMARK 999
Ile 25	Thr 49	SEE REMARK 999
Ser 31	Ile 55	SEE REMARK 999
Ile 41	Thr 65	SEE REMARK 999
Ser 114	Ala 138	SEE REMARK 999
Ser 144	Asn 168	SEE REMARK 999
Lys 163	Asn 187	SEE REMARK 999
Asp 172	Asn 196	SEE REMARK 999
Val 187	Leu 211	SEE REMARK 999

Contents of the asymmetric unit

Polymers	Number of chains	4
	Total formula weight	69705.4
Non-Polymers*	Number of molecules	8
	Total formula weight	864.2
All*	Total formula weight	70569.6

*Water molecules are not included.