Structure of PDB 1ktw Chain A

Receptor sequence

>1ktwA (length=457)

VSPKTYKDADFYVAPTQQDVNYDLVDDFGANGNDTSDDSNALQRAINAIS
RKPNGGTLLIPNGTYHFLGIQMKSNVHIRVESDVIIKPTWNGDGKNHRLF
EVGVNNIVRNFSFQGLGNGFLVDFKDSRDKNLAVFKLGDVRNYKISNFTI
DDNKTIFASILVDVTERNGRLHWSRNGIIERIKQNNALFGYGLIQTYGAD
NILFRNLHSEGGIALRMETDNLLMKNYKQGGIRNIFADNIRCSKGLAAVM
FGPHFMKNGDVQVTNVSSVSCGSAVRSDSGFVELFSPTDEVHTRQSWKQA
VESKLGRGCAQTPYAWAARVTQKDACLDKAKLEYGIEPGSFGTVKVFDVT
ARFGYNADLKQDQLDYFSTSNPMCKRVCLPTKEQWSKQGQIYIGPSLAAV
IDTTPETSKYDYDVKTFNVKRINFPVNSHKTIDTNTESSRVCNYYGMSEC
SSSRWER

3D structure

• PDB: 1ktw The Structural Bases of the Processive Degradation of iota-Carrageenan, a Main Cell Wall Polysaccharide of Red Algae.
• Chain: A
• Resolution: 2.0 Å

Enzymatic activity

• Enzyme Commision number: 3.2.1.157: iota-carrageenase.

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	G4S	A	N123 R125	N96 R98
BS02	DGS	A	K122 N123	K95 N96
BS03	G4S	A	R321 Y479	R294 Y445
BS04	DGS	A	Y341 A342 G423 Q424	Y314 A315 G389 Q390
BS05	G4S	A	Y341 R353 K394	Y314 R319 K360
BS06	DGS	A	E245 R303 K394	E218 R276 K360
BS07	CA	A	T438 D445 Y446 D447	T404 D411 Y412 D413
BS08	CA	A	S109 N145 G146	S82 N118 G119
BS09	CA	A	N58 D61 S63 D65	N31 D34 S36 D38
BS10	CA	A	D445 D447	D411 D413

Gene Ontology

Molecular Function

• GO:0016798 hydrolase activity, acting on glycosyl bonds
• GO:0033952 iota-carrageenase activity

Biological Process

• GO:0000272 polysaccharide catabolic process
• GO:0071555 cell wall organization

Cellular Component

• GO:0005576 extracellular region

External links

• PDB: RCSB:1ktw, PDBe:1ktw, PDBj:1ktw
• PDBsum: 1ktw
• PubMed: 14623184
• UniProt: Q9F5I8|CGIA_ALTMA Iota-carrageenase (Gene Name=cgiA)