Structure of PDB 1k21 Chain H

Receptor sequence

>1k21H (length=249) Species: 9606 (Homo sapiens)

IVEGSDAEIGMSPWQVMLFRKSPQELLCGASLISDRWVLTAAHCLLYPPW
DKNFTENDLLVRIGKHSRTRYERNIEKISMLEKIYIHPRYNWRENLDRDI
ALMKLKKPVAFSDYIHPVCLPDRETAASLLQAGYKGRVTGWGNLKETGQP
SVLQVVNLPIVERPVCKDSTRIRITDNMFCAGYKPDEGKRGDACEGDSGG
PFVMKSPFNNRWYQMGIVSWGEGCDRDGKYGFYTHVFRLKKWIQKVIDQ

3D structure

• PDB: 1k21 Factorising ligand affinity: a combined thermodynamic and crystallographic study of trypsin and thrombin inhibition.
• Chain: H
• Resolution: 1.86 Å

Enzymatic activity

• Enzyme Commision number: 3.4.21.5: thrombin.

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	peptide	H	E23 G25 M26 P28 W29 D116 H119 P120 C122 Y134 K135 R137 N159 M201 K202 N205 R206 W207	E8 G10 M11 P13 W14 D113 H116 P117 C119 Y134 K135 R137 N157 M204 K205 N210 R211 W212
BS02	peptide	H	F34 Q38 L40 L65 R73 T74 Y76 K81 I82 M84	F19 Q24 L26 L60 R68 T69 Y71 K77 I78 M80
BS03	NA	H	D221 R221A D222 K224	D225 R226 D227 K229
BS04	NA	H	K169 D170 T172	K167 D168 T170
BS05	IGN	H	H57 Y60A W60D D189 A190 C191 S195 S214 W215 G216 E217 G219	H43 Y47 W50 D192 A193 C194 S198 S219 W220 G221 E222 G223	MOAD: Ki=4.2nM PDBbind-CN: -logKd/Ki=8.38,Ki=4.2nM BindingDB: Ki=15nM,IC50=1300nM

Gene Ontology

Molecular Function

• GO:0004252 serine-type endopeptidase activity
• GO:0005509 calcium ion binding

Biological Process

• GO:0006508 proteolysis
• GO:0007596 blood coagulation

External links

• PDB: RCSB:1k21, PDBe:1k21, PDBj:1k21
• PDBsum: 1k21
• PubMed: 11676542
• UniProt: P00734|THRB_HUMAN Prothrombin (Gene Name=F2)