2NTI

Crystal structure of PCNA123 heterotrimer.

Entity

Entity ID	Chain ID	Description	Type	Chain length	Formula weight	Number of molecules	DB Name (Accession)	Biological source	Descriptive keywords
1	D, A, G	DNA polymerase sliding clamp B	polymer	249	27521.7	3	UniProt (P57766) Pfam (PF00705) In PDB	Sulfolobus solfataricus	Proliferating cell nuclear antigen homolog B, PCNA B
2	E, B, H	DNA polymerase sliding clamp C	polymer	246	27592.3	3	UniProt (Q97Z84) Pfam (PF00705) Pfam (PF02747) In PDB	Sulfolobus solfataricus	Proliferating cell nuclear antigen homolog C, PCNA C
3	F, C, I	DNA polymerase sliding clamp A	polymer	244	27489.1	3	UniProt (P57765) Pfam (PF00705) Pfam (PF02747) In PDB	Sulfolobus solfataricus	Proliferating cell nuclear antigen homolog A, PCNA A
4	F, H, A, I, D...	BROMIDE ION	non-polymer		79.9	54	Chemie (BR)
5	H	POTASSIUM ION	non-polymer		39.1	1	Chemie (K)
6	H	2,5,8,11,14,17,20,23-OCTAOXAPENTACOSAN-25-OL	non-polymer		384.5	1	Chemie (7PG)
7		water	water		18.0	1046	Chemie (HOH)

Sequence modifications

D, A, G: 1 - 249 (UniProt: P57766)

PDB	External Database	Details
Val 2	Phe 2	engineered mutation

E, B, H: 2 - 246 (UniProt: Q97Z84)

PDB	External Database	Details
Met 1	-	initiating methionine

Contents of the asymmetric unit

Polymers	Number of chains	9
	Total formula weight	247809.3
Non-Polymers*	Number of molecules	56
	Total formula weight	4738.4
All*	Total formula weight	252547.7

*Water molecules are not included.