1PYW

Human class II MHC protein HLA-DR1 bound to a designed peptide related to influenza virus hemagglutinin, FVKQNA(MAA)AL, in complex with staphylococcal enterotoxin C3 variant 3B2 (SEC3-3B2)

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)
2	B	HLA class II histocompatibility antigen, DR-1 beta chain	polymer	190	22080.7	1	UniProt (P13758) Pfam (PF00969) Pfam (PF07654) UniProt (by SIFTS) (P01911) In PDB	Homo sapiens (human)
3	C	9-residue influenza virus hemagglutinin related peptide FVKQNA(MAA)AL	polymer	10	1002.2	1	GenBank (3212739) UniProt (by SIFTS) (P03437) In PDB
4	D	Enterotoxin type C-3	polymer	239	27721.1	1	UniProt (P23313) Pfam (PF01123) Pfam (PF02876) UniProt (by SIFTS) (P0A0L3) In PDB	Staphylococcus aureus subsp. aureus Mu50	SEC3
5		water	water		18.0	414	Chemie (HOH)

Sequence modifications

C: 1 - 9 (GenBank: 3212739)

PDB	External Database	Details
Phe 1	Tyr 308	engineered mutation
Ala 6	Thr 313	engineered mutation
Maa 7	Leu 314	engineered mutation
Ala 8	Lys 315	engineered mutation

D: 1 - 239 (UniProt: P23313)

PDB	External Database	Details
Ser 43	Lys 70	engineered mutation
Phe 45	Leu 72	engineered mutation
Lys 46	Ala 73	engineered mutation
Trp 47	His 74	engineered mutation

Contents of the asymmetric unit

Polymers	Number of chains	4
	Total formula weight	71959.8
All*	Total formula weight	71959.8

*Water molecules are not included.