2CIO

The high resolution x-ray structure of papain complexed with fragments of the Trypanosoma brucei cysteine protease inhibitor ICP.

Functional Information from GO Data

Chain	GOid	namespace	contents
A	0006508	biological_process	proteolysis
A	0008234	molecular_function	cysteine-type peptidase activity
B	0004869	molecular_function	cysteine-type endopeptidase inhibitor activity

Functional Information from PDB Data

site_id	AC1
Number of Residues	6
Details	BINDING SITE FOR RESIDUE ACT A1218

Chain	Residue
A	LYS17
A	ASN18
A	ARG83
A	ARG93
A	TYR94
A	HOH2014

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site_id	AC2
Number of Residues	6
Details	BINDING SITE FOR RESIDUE ACT A1219

Chain	Residue
A	LYS139
A	ASP140
A	HOH2121
A	GLU3
A	ARG59
A	GLY138

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site_id	AC3
Number of Residues	6
Details	BINDING SITE FOR RESIDUE ACT A1220

Chain	Residue
A	CYS56
A	TYR78
A	CYS95
A	ARG98
A	GOL1217
A	HOH2158

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site_id	AC4
Number of Residues	5
Details	BINDING SITE FOR RESIDUE GOL A1216

Chain	Residue
A	VAL13
A	THR14
A	PRO15
A	VAL16
A	TYR186

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site_id	AC5
Number of Residues	12
Details	BINDING SITE FOR RESIDUE GOL A1217

Chain	Residue
A	GLU3
A	TYR4
A	ARG59
A	GLN73
A	LEU74
A	GLN77
A	TYR78
A	ACT1220
A	HOH2004
A	HOH2047
A	HOH2050
A	HOH2064

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Functional Information from PROSITE/UniProt

site_id	PS00139
Number of Residues	12
Details	THIOL_PROTEASE_CYS Eukaryotic thiol (cysteine) proteases cysteine active site. QGsCGSCWAfSA

Chain	Residue	Details
A	GLN19-ALA30

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site_id	PS00639
Number of Residues	11
Details	THIOL_PROTEASE_HIS Eukaryotic thiol (cysteine) proteases histidine active site. VDHAVAAVGYG

Chain	Residue	Details
A	VAL157-GLY167

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site_id	PS00640
Number of Residues	20
Details	THIOL_PROTEASE_ASN Eukaryotic thiol (cysteine) proteases asparagine active site. YILiKNSWgtgWGenGYIrI

Chain	Residue	Details
A	TYR170-ILE189

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Functional Information from SwissProt/UniProt

site_id	SWS_FT_FI1
Number of Residues	1
Details	ACT_SITE: ACT_SITE => ECO:0000255|PROSITE-ProRule:PRU10088, ECO:0000269|PubMed:5681232, ECO:0000269|PubMed:6502713, ECO:0000269|PubMed:952885, ECO:0000305|PubMed:1860874, ECO:0007744|PDB:1PAD, ECO:0007744|PDB:9PAP

Chain	Residue	Details
A	OCS25

---

site_id	SWS_FT_FI2
Number of Residues	1
Details	ACT_SITE: ACT_SITE => ECO:0000255|PROSITE-ProRule:PRU10089, ECO:0000269|PubMed:6502713, ECO:0000269|PubMed:952885, ECO:0007744|PDB:1PAD, ECO:0007744|PDB:9PAP

Chain	Residue	Details
A	HIS159

---

site_id	SWS_FT_FI3
Number of Residues	1
Details	ACT_SITE: ACT_SITE => ECO:0000255|PROSITE-ProRule:PRU10090, ECO:0000269|PubMed:5681232, ECO:0000269|PubMed:6502713, ECO:0000269|PubMed:952885, ECO:0007744|PDB:1PAD, ECO:0007744|PDB:9PAP

Chain	Residue	Details
A	ASN175

---

site_id	SWS_FT_FI4
Number of Residues	1
Details	BINDING: covalent => ECO:0000269|PubMed:8416808, ECO:0007744|PDB:1POP

Chain	Residue	Details
A	OCS25

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Catalytic Information from CSA

site_id	MCSA1
Number of Residues	4
Details	M-CSA 174

Chain	Residue	Details
A	GLN19	electrostatic stabiliser, hydrogen bond donor
A	HIS159	electrostatic stabiliser, hydrogen bond acceptor, hydrogen bond donor, proton acceptor, proton donor
A	ASN175	activator, electrostatic stabiliser, hydrogen bond acceptor
A	OCS25	electrostatic stabiliser

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