Structure of PDB 1tx3 Chain A

Receptor sequence

>1tx3A (length=249) Species: 727 (Haemophilus influenzae)

SFIKPIYQDINSILIGQKVKRPAAGEPFEKLVYKFLKENLSDLTFKQYEY
LNDLFMKNPAIIGHEARYKLFNSPTLLFLLSRGKAATENWSIENLFEEKQ
NDTADILLVKDQFYELLDVKTRNISKSAQAPNIISAYKLAQTCAKMIDNK
EFDLFDINYLEVDWELNGEDLVCVSTSFAELFKSEPSELYINWAAAMQIQ
FHVRDLDQGFNGTREEWAKSYLKHFVTQAEQRAISMIDKFVKPFKKYIL

3D structure

• PDB: 1tx3 Ca2+ binding in the active site of HincII: implications for the catalytic mechanism
• Chain: A
• Resolution: 2.5 Å

Enzymatic activity

• Enzyme Commision number: 3.1.21.4: type II site-specific deoxyribonuclease.

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	Y77 S90 K93 Q109 Q138 Y199 N201 A204 K248	Y68 S81 K84 Q100 Q129 Y190 N192 A195 K239
BS02	dna	A	Q109 N110 D114 D127 K129 T130 N132 K135 S136 A137 Q138 P140 N141 S144 K147 A205 M206 Q207	Q100 N101 D105 D118 K120 T121 N123 K126 S127 A128 Q129 P131 N132 S135 K138 A196 M197 Q198
BS03	NA	A	D127 I142 I143	D118 I133 I134

Gene Ontology

Molecular Function

• GO:0003677 DNA binding
• GO:0004519 endonuclease activity
• GO:0009036 type II site-specific deoxyribonuclease activity

Biological Process

• GO:0009307 DNA restriction-modification system

External links

• PDB: RCSB:1tx3, PDBe:1tx3, PDBj:1tx3
• PDBsum: 1tx3
• PubMed: 15491133
• UniProt: P17743|T2C2_HAEIF Type II restriction enzyme HincII (Gene Name=hincIIR)