Mechanism	Retaining a
Clan	GH-H
3D Structure Status	( β / α ) 8 barrel
Catalytic Nucleophile/Base	Asp (experimental)
Catalytic Proton Donor	Glu (experimental)
Note	New: many members have been assigned to subfamilies as described by Stam et al. (2006) Protein Eng Des Sel. 19, 555-562 (PMID: 17085431)
External resources	CAZypedia; EBI Protein of the Month; PDB Molecule of the Month;
Statistics	GenBank accession (77); Uniprot accession (43); PDB accession (17); 3D entries (7); cryst (0)

Archaea
Protein Name	EC#	Organism	GenBank	Uniprot	PDB/3D Carbohydrate Ligands Resolution (Å)	Subf
isoamylase / 4-α-glucanotransferase (TreX;SSO2094;GlgX;ORF-c06_004;c06021)	3.2.1.68 2.4.1.25	Saccharolobus solfataricus P2	AAK42273.1 CAA69504.1 CAC23738.1 NP_343483.1	P95868 Q7LX99	2VNC[A,B] 3.0 2VR5[A,B] α-D-Glcp <non_carb>-(1-4)-α-D-6-deoxy-Glcp4N-(1-4)-β-D-Glcp-(1-4)-ASP 2.8 2VUY[A,B] 3.0 7EAV[A,B] 2.80	11
Bacteria
Protein Name	EC#	Organism	GenBank	Uniprot	PDB/3D Carbohydrate Ligands Resolution (Å)	Subf
isoamylase (EcoGlgX; GlgX; b3431)	3.2.1.68	Escherichia coli str. K-12 substr. MG1655	AAC76456.1 AAA58229.1 AAA98735.1 AIZ89569.1 ALI38889.1 AMC96314.1 AUG18134.1 AVI53590.1 AYG17627.1 CAP11380.1 NP_417889.1	P15067	2WSK[A] 2.25	11
isoamylase (Iam; IsoA; ISO)	3.2.1.68	Pseudomonas sp. amyloderamosa SB-15	AAA25854.1 CAA31754.1	P10342	1BF2[A] 2.00	11
glycogen debranching enzyme (GlgX; AQF52_6078)	3.2.1.68	Streptomyces venezuelae ATCC 15439	ALO11671.1	A0A5P2ALW6	7U39[A,B,C,D,E,F,G,H,I,J, 3.51 7U3A[A,B,C,D] 3.34 7U3B[A,B,C,D,E,F,G,H] <non_carb>-(1-4)-α-D-6-deoxy-Glcp4N-(1-4)-β-D-Glcp-(1-4)-ASP <non_carb>-(1-4)-α-D-6-deoxy-Glcp4N-(1-4)-D-1-deoxy-Glcp 3.60 7U3D[A,B,C,D] <non_carb>-(1-4)-α-D-6-deoxy-Glcp4N-(1-4)-α-D-Glcp-(1-4)-α-D-Glcp 2.40	11
Eukaryota
Protein Name	EC#	Organism	GenBank	Uniprot	PDB/3D Carbohydrate Ligands Resolution (Å)	Subf
isoamylase 1 (Isa1;CrISA1;Sta7)	3.2.1.68	Chlamydomonas reinhardtii CC425	AAP85534.1 AAP88032.1 CAZ78881.1	Q7X8Q2	4J7R[A,B] 2.30 4OKD[A,B] α-D-Glcp α-D-Glcp-(1-4)-α-D-Glcp-(1-4)-α-D-Glcp α-D-Glcp-(1-4)-α-D-Glcp-(1-4)-α-D-Glcp-(1-4)-α-D-Glcp-(1-4)-α-D-Glcp-(1-4)-α-D-Glcp-(1-4)-β-D-Glcp-(1-4)-ASP 2.40	11
isoamylase 1 (Isa1; OsISA1; Su1; Sugary-1; Os08g0520900)	3.2.1.68	Oryza sativa Japonica Group	BAC75533.1 ACY56086.1 AII21927.1 BAA29041.1 BAF24185.1 BAT06299.1	D0TZF0 D0TZF0 O80403 Q84L53	9J60[A,B] 2.70 9J6X[A,B] 2.40 9LFN[A,B]	11
Os05g0393700 (OsISA2)		Oryza sativa Japonica Group	AAT93894.1 BAF17370.1 BAS93869.1		9J6X[C] 2.40 9LFN[C]	11
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