Structure of PDB 1dct Chain B

Receptor sequence

>1dctB (length=324) Species: 725 (Haemophilus influenzae biotype aegyptius)

MNLISLFSGAGGLDLGFQKAGFRIICANEYDKSIWKTYESNHSAKLIKGD
ISKISSDEFPKCDGIIGGPPCQSWSEGGSLRGIDDPRGKLFYEYIRILKQ
KKPIFFLAENVKGMMAQRHNKAVQEFIQEFDNAGYDVHIILLNANDYGVA
QDRKRVFYIGFRKELNINYLPPIPHLIKPTFKDVIWDLKDNPIPALDKNK
TNGNKCIYPNHEYFIGSYSTIFMSRNRVRQWNEPAFTVQASGRQCQLHPQ
APVMLKVSKNLNKFVEGKEHLYRRLTVRECARVQGFPDDFIFHYESLNDG
YKMIGNAVPVNLAYEIAKTIKSAL

3D structure

• PDB: 1dct The crystal structure of HaeIII methyltransferase convalently complexed to DNA: an extrahelical cytosine and rearranged base pairing.
• Chain: B
• Resolution: 2.8 Å

Enzymatic activity

• Enzyme Commision number: 2.1.1.37: DNA (cytosine-5-)-methyltransferase.

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	B	F7 Y30 P70 P86 R87 L90	F7 Y30 P70 P86 R87 L90
BS02	dna	B	G68 P69 P70 C71 S75 E76 G77 R81 R87 E109 V111 R155 I221 R225 R227 F236 T237 Q239 Q244 G305 N306	G68 P69 P70 C71 S75 E76 G77 R81 R87 E109 V111 R155 I221 R225 R227 F236 T237 Q239 Q244 G305 N306
BS03	dna	B	K112 A116 K198 S219 T220 I221 R225 R243 N260	K112 A116 K198 S219 T220 I221 R225 R243 N260

Gene Ontology

Molecular Function

• GO:0003677 DNA binding
• GO:0003886 DNA (cytosine-5-)-methyltransferase activity
• GO:0005524 ATP binding
• GO:0008168 methyltransferase activity

Biological Process

• GO:0009307 DNA restriction-modification system
• GO:0032259 methylation

External links

• PDB: RCSB:1dct, PDBe:1dct, PDBj:1dct
• PDBsum: 1dct
• PubMed: 7606780
• UniProt: P20589|MTH3_HAEAE Type II methyltransferase M.HaeIII (Gene Name=haeIIIM)