Structure of PDB 1i8j Chain B

Receptor sequence

>1i8jB (length=323) Species: 562 (Escherichia coli)

TDLIQRPRRLRKSPALRAMFEETTLSLNDLVLPIFVEEEIDDYKAVEAMP
GVMRIPEKHLAREIERIANAGIRSVMTFGISHHTDETGSDAWREDGLVAR
MSRICKQTVPEMIVMSDTCFCEYTSHGHCGVLCEHGVDNDATLENLGKQA
VVAAAAGADFIAPSAAMDGQVQAIRQALDAAGFKDTAIMSYSTKFASSFY
GPFREAAGSALKGDRKSYQMNPMNRREAIRESLLDEAQGADCLMVKPAGA
YLDIVRELRERTELPIGAYQVSGEYAMIKFAALAGAIDEEKVVLESLGSI
KRAGADLIFSYFALDLAEKKILR

3D structure

• PDB: 1i8j Mechanistic basis for suicide inactivation of porphobilinogen synthase by 4,7-dioxosebacic acid, an inhibitor that shows dramatic species selectivity.
• Chain: B
• Resolution: 1.9 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): K194 K246
• Catalytic site (residue number reindexed from 1): K194 K246
• Enzyme Commision number: 4.2.1.24: porphobilinogen synthase.

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	ZN	B	C119 C121 C129	C119 C121 C129
BS02	DSB	B	S164 Y191 K194 Y200 F203 R204 R215 Q219 K246 Y269 V271 S272 Y311	S164 Y191 K194 Y200 F203 R204 R215 Q219 K246 Y269 V271 S272 Y311

Gene Ontology

Molecular Function

• GO:0000287 magnesium ion binding
• GO:0004655 porphobilinogen synthase activity
• GO:0008270 zinc ion binding
• GO:0016829 lyase activity
• GO:0046872 metal ion binding

Biological Process

• GO:0006782 protoporphyrinogen IX biosynthetic process
• GO:0006783 heme biosynthetic process
• GO:0033014 tetrapyrrole biosynthetic process

Cellular Component

• GO:0005829 cytosol

External links

• PDB: RCSB:1i8j, PDBe:1i8j, PDBj:1i8j
• PDBsum: 1i8j
• PubMed: 11444968
• UniProt: P0ACB2|HEM2_ECOLI Delta-aminolevulinic acid dehydratase (Gene Name=hemB)