Structure of PDB 1tx3 Chain C

Receptor sequence

>1tx3C (length=255) Species: 727 (Haemophilus influenzae)

SFIKPIYQDINSILIGQKVKRPKSGTLSGHAAGEPFEKLVYKFLKENLSD
LTFKQYEYLNDLFMKNPAIIGHEARYKLFNSPTLLFLLSRGKAATENWSI
ENLFEEKQNDTADILLVKQFYELLDVKTRNISKSAQAPNIISAYKLAQTC
AKMIDNKEFDLFDINYLEVDWELNGEDLVCVSTSFAELFKSEPSELYINW
AAAMQIQFHVRDLDQGFNGTREEWAKSYLKHFVTQAEQRAISMIDKFVKP
FKKYI

3D structure

• PDB: 1tx3 Ca2+ binding in the active site of HincII: implications for the catalytic mechanism
• Chain: C
• 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	C	Y77 G92 K93 Q109 Q138 Y199 N201 A203 A204 K248	Y76 G91 K92 Q108 Q136 Y197 N199 A201 A202 K246
BS02	dna	C	H31 Q109 N110 T130 R131 N132 K135 S136 A137 Q138 P140 N141 S144 Y146 K147 A205 M206 Q207	H30 Q108 N109 T128 R129 N130 K133 S134 A135 Q136 P138 N139 S142 Y144 K145 A203 M204 Q205
BS03	NA	C	D127 I142 I143	D125 I140 I141

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)