Structure of PDB 1hex Chain A

Receptor sequence

>1hexA (length=345) Species: 274 (Thermus thermophilus)

MKVAVLPGDGIGPEVTEAALKVLRALDEAEGLGLAYEVFPFGGAAIDAFG
EPFPEPTRKGVEEAEAVLLGSVGGPKWDGLPRKIRPETGLLSLRKSQDLF
ANLRPAKVFPGLERLSPLKEEIARGVDVLIVRELTGGIYFGEPRGMSEAE
AWNTERYSKPEVERVARVAFEAARKRRKHVVSVDKANVLEVGEFWRKTVE
EVGRGYPDVALEHQYVDAMAMHLVRSPARFDVVVTGNIFGDILSDLASVL
PGSLGLLPSASLGRGTPVFEPVHGSAPDIAGKGIANPTAAILSAAMMLEH
AFGLVELARKVEDAVAKALLETPPPDLGGSAGTEAFTATVLRHLA

3D structure

• PDB: 1hex Structure of 3-isopropylmalate dehydrogenase in complex with NAD+: ligand-induced loop closing and mechanism for cofactor specificity.
• Chain: A
• Resolution: 2.5 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): Y139 K185 D217 D241 D245
• Catalytic site (residue number reindexed from 1): Y139 K185 D217 D241 D245
• Enzyme Commision number: 1.1.1.85: 3-isopropylmalate dehydrogenase.

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	NAD	A	I11 G73 G74 D78 E87 L254 H273 G274 S275 A276 D278 I279 N286	I11 G73 G74 D78 E87 L254 H273 G274 S275 A276 D278 I279 N286	MOAD: Ki=614.6uM

Gene Ontology

Molecular Function

• GO:0000287 magnesium ion binding
• GO:0003862 3-isopropylmalate dehydrogenase activity
• GO:0016491 oxidoreductase activity
• GO:0016616 oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP as acceptor
• GO:0042802 identical protein binding
• GO:0046872 metal ion binding
• GO:0051287 NAD binding

Biological Process

• GO:0009098 L-leucine biosynthetic process

Cellular Component

• GO:0005737 cytoplasm
• GO:0005829 cytosol

External links

• PDB: RCSB:1hex, PDBe:1hex, PDBj:1hex
• PDBsum: 1hex
• PubMed: 7881901
• UniProt: Q5SIY4|LEU3_THET8 3-isopropylmalate dehydrogenase (Gene Name=leuB)