Structure of PDB 3igc Chain A

Receptor sequence

>3igcA (length=313) Species: 10255 (Variola virus)

MRALFYKDGKLFTDNNFLNPVSDNNPAYEVLQHVKIPTHLTDVVVYGQTW
EEALTRLIFVGSDSKGRRQYFYGKMHVQNRNAKRDRIFVRVYNVMKRINS
FINKNIKKSSTDSNYQLAVFMLMETMFFIRFGKMKYLKENETVGLLTLKN
KHIEISPDKIVIKFVGKDKVSHEFVVHKSNRLYKPLLKLTDDSSPEEFLF
NKLSERKVYESIKQFGIRIKDLRTYGVNYTFLYNFWTNVKSISPLPSPKK
LIALTIKQTAEVVGHTPSISKRAYMATTILEMVKDKNFLDVVSKTTFDEF
LSIVVDHVKSSTD

3D structure

• PDB: 3igc Insights from the Structure of a Smallpox Virus Topoisomerase-DNA Transition State Mimic.
• Chain: A
• Resolution: 2.1 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): R130 K167 R223 H265 Y274
• Catalytic site (residue number reindexed from 1): R130 K167 R223 H265 Y274
• Enzyme Commision number: 5.6.2.1: DNA topoisomerase.

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	dna	A	Y70 Y72 H76 R80 K138 K167 R206 K220 A273 Y274	Y70 Y72 H76 R80 K138 K167 R206 K220 A273 Y274
BS02	dna	A	R130 K167 D168 T266 I269 R272	R130 K167 D168 T266 I269 R272
BS03	dna	A	H39 K65 R67 Q69 R130 F131 G132 K133 Y136 N140 T142 K167 D168 R218 K220 K271	H39 K65 R67 Q69 R130 F131 G132 K133 Y136 N140 T142 K167 D168 R218 K220 K271
BS04	VO4	A	R130 R223 Y274	R130 R223 Y274

Gene Ontology

Molecular Function

• GO:0003677 DNA binding
• GO:0003916 DNA topoisomerase activity
• GO:0003917 DNA topoisomerase type I (single strand cut, ATP-independent) activity

Biological Process

• GO:0006265 DNA topological change

Cellular Component

• GO:0044423 virion component

External links

• PDB: RCSB:3igc, PDBe:3igc, PDBj:3igc
• PDBsum: 3igc
• PubMed: 20152159
• UniProt: P32989|TOP1_VAR67 DNA topoisomerase 1 (Gene Name=OPG111)