Structure of PDB 1k1n Chain A

Receptor sequence

>1k1nA (length=223) Species: 9913 (Bos taurus)

IVGGYTCGANTVPYQVSLNSGYHFCGGSLINSQWVVSAAHCYKSGIQVRL
GEDNINVVEGNEQFISASKSIVHPSYNSNTLNNDIMLIKLKSAASLNSRV
ASISLPTSCASAGTQCLISGWGNTKSSGTSYPDVLKCLKAPILSDSSCKS
AYPGQITSNMFCAGYLEGGKDSCQGDSGGPVVCSGKLQGIVSWGSGCAQK
NKPGVYTKVCNYVSWIKQTIASN

3D structure

• PDB: 1k1n Factorising ligand affinity: a combined thermodynamic and crystallographic study of trypsin and thrombin inhibition.
• Chain: A
• Resolution: 2.0 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): H57 D102 Q192 G193 D194 S195 G196
• Catalytic site (residue number reindexed from 1): H40 D84 Q174 G175 D176 S177 G178
• Enzyme Commision number: 3.4.21.4: trypsin.

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	CA	A	E70 N72 V75 E80	E52 N54 V57 E62
BS02	CCR	A	H57 D189 S190 C191 Q192 S214 W215 G216 G219	H40 D171 S172 C173 Q174 S192 W193 G194 G196	MOAD: Kd=153nM PDBbind-CN: -logKd/Ki=6.82,Kd=153nM

Gene Ontology

Molecular Function

• GO:0004175 endopeptidase activity
• GO:0004252 serine-type endopeptidase activity
• GO:0005515 protein binding
• GO:0008236 serine-type peptidase activity
• GO:0046872 metal ion binding
• GO:0097655 serpin family protein binding

Biological Process

• GO:0006508 proteolysis
• GO:0007586 digestion

Cellular Component

• GO:0005576 extracellular region
• GO:0005615 extracellular space
• GO:0097180 serine protease inhibitor complex

External links

• PDB: RCSB:1k1n, PDBe:1k1n, PDBj:1k1n
• PDBsum: 1k1n
• PubMed: 11676542
• UniProt: P00760|TRY1_BOVIN Serine protease 1 (Gene Name=PRSS1)