Structure of PDB 1klk Chain A

Receptor sequence

>1klkA (length=203) Species: 4754 (Pneumocystis carinii)

QKSLTLIVALTTSYGIGRSNSLPWKLKKEISYFKRVTSFVPTFDSFESMN
VVLMGRKTWESIPLQFRPLKGRINVVITRNESLDLGNGIHSAKSLDHALE
LLYRTYGSESSVQINRIFVIGGAQLYKAAMDHPKLDRIMATIIYKDIHCD
VFFPLKFRDKEWSSVWKKEKHSDLESWVGTKVPHGKINEDGFDYEFEMWT
RDL

3D structure

• PDB: 1klk Structure-based enzyme inhibitor design: modeling studies and crystal structure analysis of Pneumocystis carinii dihydrofolate reductase ternary complex with PT653 and NADPH.
• Chain: A
• Resolution: 2.3 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): L25 E32
• Catalytic site (residue number reindexed from 1): L22 E29
• Enzyme Commision number: 1.5.1.3: dihydrofolate reductase.

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	PMD	A	I10 V11 S24 L25 E32 I33 F36 S64 F69 I123	I7 V8 S21 L22 E29 I30 F33 S61 F66 I120	MOAD: ic50=0.21uM BindingDB: IC50=210nM
BS02	NDP	A	V11 A12 I19 N23 G58 R59 K60 T61 I80 T81 R82 I123 G124 G125 A126 Q127 L128	V8 A9 I16 N20 G55 R56 K57 T58 I77 T78 R79 I120 G121 G122 A123 Q124 L125

Gene Ontology

Molecular Function

• GO:0004146 dihydrofolate reductase activity
• GO:0016491 oxidoreductase activity
• GO:0050661 NADP binding

Biological Process

• GO:0006730 one-carbon metabolic process
• GO:0046452 dihydrofolate metabolic process
• GO:0046654 tetrahydrofolate biosynthetic process
• GO:0046655 folic acid metabolic process

Cellular Component

• GO:0005739 mitochondrion

External links

• PDB: RCSB:1klk, PDBe:1klk, PDBj:1klk
• PDBsum: 1klk
• PubMed: 12037296
• UniProt: P16184|DYR_PNECA Dihydrofolate reductase